LEAP 2013 Uppsala SE

In the talk, I will review briefly theoretical models and concepts associated with the potential violation of fundamental (space-time) symmetries, either discrete, such as T and CPT, or continuous, such as Lorentz Invariance, which may be encountered in quantum gravity. I will give an overview of how to test such symmetries, with particular emphasis on using low-energy antiprotons and cold antihydrogen atoms, of interest to this conference.

The availability of antiprotons has enabled novel experiments to test fundamental symmetries and to determine several fundamental constants which are otherwise unaccessible. Such experiments which are primarily concerned with the simplest and lightest possible antiprotonic atom such as antiprotonic hydrogen or antiprotonic helium which are used to investigate the basic interations and fundamental symmetries in nature. The present status of ongoing projects will be reviewed, novel possibilities will be discussed and their often unique potential to test model building in fundamental physical theory and test precise calculations will be covered.

The CPT invariance of all relativistic quantum field theories involved in the Standard Model defines that particles and their corresponding antiparticles have the same fundamental properties. Masses and lifetimes are identical, as well as charges and magnetic moments, the latter two with opposite sign. BASE is testing the CPT invariance by a high-precision comparison of the proton and antiproton magnetic moments. The determination of the magnetic moment is based on the measurement of the frequency ratio of the spin-precession (also called Larmor) frequency and the cyclotron frequency in a Penning trap. Thereby, the g-factor is obtained, which measures the magnetic moment in units of the nuclear magnetron. The cyclotron frequency is obtained by detection of image currents induced in the Penning trap electrodes by the particle’s motion. The Larmor frequency is determined by the application of the continuous Stern-Gerlach effect. In this elegant scheme for the non-destructive detection of the spin eigenstate a strong magnetic bottle is superimposed to the Penning trap, which couples the magnetic moment of the particle to its axial motion. Thus, the spin-state analysis is reduced to an axial frequency measurement. A magnetic radiofrequency field is used to drive spin-flips of the (anti)proton, and the spin-flip probability as function of the spin-flip drive frequency is recorded to obtain the Larmor frequency. Currently, the proton and antiproton magnetic moments are compared with a relative precision of 4.4 ppm measured in a Penning trap with a strong magnetic bottle. BASE intends to perform a measurement of the antiproton magnetic moment with a three orders of magnitude higher precision by using the so-called double Penning trap technique. In this measurement scheme, the frequency measurements are carried out in a Penning trap with a homogeneous magnetic field, while the spin-state analysis is spatially separated in a second Penning trap with magnetic bottle. Thereby, the line widths of the measured frequencies are significantly reduced. Recently, the double-trap technique has been demonstrated for the first time with a single proton at the BASE companion experiment in Mainz. This paves the way for a high-precision measurement of the antiproton magnetic moment on the ppb level with BASE at the Antiproton Decelerator (AD) at CERN. Currently, the work to integrate BASE into the AD hall is in progress. A new experimental zone as well as a new antiproton transfer beam line are under construction and will be prepared until the end of the long shutdown LS1. The design of the BASE apparatus is complete and currently highly sensitive single particle detection systems are being developed. The experiment will be commissioned in the new area in order to prepare for the first on-line operation in 2014. The current status of BASE is presented.

In March 2012 the ALPHA Collaboration reported data from an experiment in which transitions between hyperfine levels of magnetically-trapped ground state antihydrogen atoms were selectively induced and monitored [1]. Those data comprise the first – albeit crude – direct spectroscopic probe of a pure antimatter atom, and mark the advent of an era in which precision comparisons of hydrogen and antihydrogen are expected to become a reality. I will describe the experiment that was performed by the ALPHA Collaboration, comment on its significance, and discuss prospects for hyperfine microwave spectroscopy in future tests of CPT symmetry with antihydrogen. [1] Amole et al., Nature 483, 439 (2012).

Antihydrogen (¯H) atoms are produced via laser-controlled, two-stage charge exchange in a cryogenic Penning trap. 6x10^6 antiprotons (¯p) and 3x10^8 positrons (e+) are held in a nested well potential structure. Cs* atoms, produced via laser excitation within the cryogenic Penning trap, travel radially across the trap and through the e+ plasma to produce Ps*. The Ps* atoms are produced isotropically, with some atoms moving along the axis of the Penning trap and interacting with the cold ¯p via a second charge exchange to form potentially very cold ¯H. ¯H formation is detected by comparing the ¯p annihilation counts with Cs excited to the Rydberg state to those obtained when the Cs remains in the ground state.

Detailed comparisons of anti-hydrogen with hydrogen promise to be a fruitful test bed of fundamental symmetries such as the CPT Theorem for quantum field theory or　studies of gravitational influence on antimatter. With a string of recent successes, starting　with the first trapped anti-hydrogen and recently resulting in the first measurement of a quantum transition in anti-hydrogen, the ALPHA collaboration is well on its way to perform such precision comparisons. We will discuss the key innovative steps that has made these feats possible and in particular focus on the detailed work on positron and antiproton preparation to achieve anti-hydrogen cold enough to trap as well as the unique features of the ALPHA apparatus that has allowed the first quantum transitions in anti-hydrogen to be measured with only a single trapped anti-hydrogen atom per experiment. We will also look at how ALPHA plans to step from here towards more precise comparisons of matter and antimatter and what we could possibly learn from such comparisons.

Peter von Ballmoos Antimatter in the Universe is best probed through ordinary matter, the resulting annihilation-radiation providing indirect evidence for its presence. The observations of high energy (~100 MeV) gamma-rays sets limits on the fraction of nuclear antimatter contained in our local and Galactic neighbourhood. Redshifted annihilation radiation, measured in the MeV range, constrains matter-antimatter domain boundaries in the dense early Universe. We review recent gamma-ray observations that set stringent upper limits on those emissions, confirming that our Universe contains predominately matter and very little antimatter. Positrons, on the other hand, are the most common and easily produced form of antimatter. A characteristic gamma-line at 511 keV emitted by the annihilation of Galactic positrons has been measured for almost four decades with balloon and satellite experiments. A first all-sky map of electron-positron radiation has now been drawn, and the physical conditions in the sites where annihilation occurs are better understood. However, the very origin of the positrons and their propagation has remained as enigmatic as ever.

The latest results from the Alpha Magnetic Spectrometer (AMS) will be presented.

for the PAMELA collaboration. On the 15th of June 2006, the PAMELA satellite-borne experiment was launched from the Baikonur cosmodrome and it has been collecting data since July 2006. The primary scientific goal is the measurement of the antiproton and positron energy spectra. Antiparticles are a natural component of the cosmic radiation being produced in the interaction between cosmic rays and the interstellar matter. They have been shown to be extremely interesting for understanding the propagation mechanisms of cosmic rays. Furthermore, novel sources of primary cosmic-ray antiparticles of either astrophysical or exotic origin (e.g. annihilation of dark matter particles) can also be probed. In this talk we will review the PAMELA antiparticle results and their significance for the field of astroparticle physics.

Sensitive tests of CPT and Lorentz symmetry performed at presently accessible energy scales provide the opportunity to probe Planck-scale physics. The gravitational Standard-Model Extension (SME) provides a comprehensive theoretical framework for these investigations. Gravitational couplings in the SME yield implications for antimatter-gravity experiments. A general theoretical overview of gravity and antimatter will be provided along with a discussion of SME-based predictions for antimatter-gravity experiments. Predictions for nongravitational tests, such as antihydrogen spectroscopy and trapped-antiparticle experiments will also be summarized.

The AEgIS experiment at CERN's AD aims at performing the first measurement of the gravitational interaction of antimatter. This will allow to expand tests of Einstein's Weak Equivalence Principle to antimatter systems. Such tests have initially been attempted with antiprotons and failed due to uncontrollable stray electric fields. The advances over the past decade in forming cold antihydrogen makes such a measurement feasible nowadays. Nevertheless, such an experiment provides substantial challenges and the interplay of various techniques from atomic, nuclear, and particle physics. We are planning to form a beam of antihydrogen via pulsed formation using 3-body recombination with laser-excited positronium and the subsequent Stark acceleration of the Rydberg antihydrogen using electric gradients. The gravitational deflection of the horizontal beam of antihydrogen will be measured using a classical Moire defelectometer. This talk will present an overview of the experiment and review the current status of the apparatus.

Resonant transitions between gravitational quantum states of antihydrogen near material surface can be induced by weak alternating magnetic field. Such an approach opens an opportunity for precision meausrement of energy spacing between quantum gravitational states and thus determination of antihydrogen gravitational mass. Behavior of antihydrogen atom near material surface in gravitational field of the Earth and alternating inhomogeneous magnetic field is studied. Characteristic field intensities and gradients required for efficient resonant transitions between gravitational states are established. The methods of precision resonant spectroscopy are analyzed.

QCD-motivated models for hadrons predict an assortment of "exotic" hadrons that have structures that are more complex then the quark-antiquark mesons and three-quark baryons of the naive quark-parton model. These include pentaquark baryons, the six-quark H-dibaryon, and tetra-quark and glueball mesons. Despite extensive experimental searches, no unambiguous candidates for any of these exotic configurations have yet to be identified. On the other hand, a number of meson states, most of which contain either charmed-anticharmed quark or bottom-antibottom quark pairs have been recently discovered that neither fit into the quark-antiquark meson picture nor match the expected properties of the QCD-inspired exotics. This talk will review the properties of these newly discovered states --the so-called XYZ mesons-- and compare them with expectations for conventional quark-antiquark and the predicted QCD-exotic meson states. In addition, near-term prospects for new results from the BESIII experiment and long-term prospects for BelleII will be discussed.

PANDA is a universal modular 4pi detector for both charged particles and photons that will study antiproton-proton and antiproton-nucleus collisions using the high-quality internal antiproton beam of the HESR storage ring at the international FAIR facility. With beam momenta between 1.5~GeV/c and 15~GeV/c a wide range of physics topics from the light up to the multi-strange and charmed hadron sector is accessible. With hadron spectroscopy, hadron structure and reaction dynamics, all relevant aspects in hadron physics are covered in the scientific program of PANDA, which this presentation will give an overview of. One of the key goals is certainly the identification of non-qbar q and also non-qqq hadrons, in particular hadrons with 'constituent' gluons which are allowed by QCD, but also to sharpen our understanding of the charmonium states below and above the Dbar D threshold. Further issues are baryon spectroscopy, in particular with strangeness, multi-strangeness and charm, studies of the reaction mechanism, in particular in hyperon-antihyperon production, a better understanding of the proton structure from electromagnetic processes, and the investigation of nuclear medium effects on hadron properties and of hard QCD reactions inside the nuclear environment. A modified detector setup will be used for the spectroscopy of double Lambda hypernuclei.

The study of the antiproton cross section on nuclei at low energies (eV-MeV region) has implications for fundamental cosmology as well as for nuclear physics. On the other hand, the existing data of antinucleon-nucleon (or -nucleus) annihilation cross-sections are confined to energies above approximately 1 MeV. The ASACUSA collaboration at CERN recently measured antiproton annihilation cross section at 5.3 MeV kinetic energy on different kinds of nuclei. Such results showed compatibility with the black-disk model with the Coulomb correction [1]. But till now experimental difficulties prevented the investigation at energies below approximately 1 MeV. We report here about the first experiment performed at much lower kinetic energies, namely approximately 130 keV. [1] A. Bianconi et al., Phys. Lett. B 704, (2011) 461;

ASACUSA (Atomic Spectroscopy And Collisions Using Slow Antiprotons) collaboration at CERN AD pursues multiple goals while sharing the same infrastructure, in particular the radiofrequency quadrupole antiproton decelerator RFQD. We have so far worked on the precision laser and microwave spectroscopy of antiprotonic helium atoms, ionization cross sections for antiproton impact on atoms and molecules, annihilation cross sections of very low energy antiprotons on nuclei, and production of antihydrogen in a "cusp" trap, aiming at the precision spectroscopy of antihydrogen ground-state hyperfine splitting. In this talk, I will give an overview of ASACUSA; details will be presented by other ASACUSA members.

The precision of laser spectroscopy of antiprotonic helium (a helium atom with one of its electrons replaced by an antiproton) has improved by almost 4 orders of magnitude over its 20 years of history. Experimental transition frequencies can be compared to 3-body QED calculations to derive the antiproton-electron mass ratio. In the latest measurements of the Asacusa experiment at CERN, two-photon transitions of antiprotonic helium were excited using two counterpropagating laser beams. This method reduces the Doppler-broadening caused by the thermal motion of the atoms, and allowed us to measure the transition frequencies with a fractional precision of 2.5-5 parts in 10^9. From these frequencies, we derived an antiproton-electron mass ratio of 1836.1526736(23). Our precision approaches that of the experimental value of the proton-electron mass ratio, and agrees with the latter within errors. Assuming CPT symmetry (i.e. $m_p=m_pbar), we further derived the electron's atomic mass as m_e=0.0005485799091(7)u from the more accurately known atomic mass of the proton.

A numerical method to calculate the Bethe logarithm for resonant states is developed. To this end we exploit the Complex Coordinate Rotation (CCR) formalism to describe resonances as time-independent solutions of the Schroedinger equation. To get a proper expression for the Bethe logarithm calculations we apply the generalization of the second order perturbation theory to isolated CCR eigenstates. Using the elaborated method we perform a systematic calculation of the Bethe logarithm for metastable states in the antiprotonic helium atoms with precision of about 7 significant digits. This precision eventually results in a relative uncertanty of ro-vibrational transition frequencies at a level of 10^{-11}.

Antiprotons have been proposed as potential modality for particle beam cancer therapy by Gray and Kalogeropoulos in 1985. This proposal was based on the enhancement of physical dose deposition near the end of range due to the annihilation of antiprotons when captured by a nucleus and the expectation of an enhanced RBE of this additional dose. Starting in 2003 the AD-4 collaboration at CERN has studied biological effects of antiproton beams on V79 Chinese Hamster cells and human FaDu cells. The AD-4 collaboration has developed relative and absolute dosimetry for pulsed antiproton beams and shot-by-shot detection of beam intensity and profile during irradiation experiments. In 2006 data from these measurements were used to benchmark the FLUKA Monte Carlo code, which then has been used for calculations of physical dose inside and outside of the primary antiproton beam. To date we have collected 5 independent data sets on clonogenic survival of V-79 Chinese Hamster cells taken under (near) identical conditions. In initial experiments using 50 MeV antiprotons we have determined biological effective dose ratios (BEDR) for peak to plateau of antiproton and proton beams of identical energies and beam conditions and found an enhancement in the antiproton case of a factor of 4. Using a clinically relevant energy of 126 MeV we generated a 1 cm deep spread-out Bragg peak (SOBP) and measured survival vs. depth along the entire beam path. Together with the the absolute dose deposited at each depth point obtained by FLUKA calculations using beam profilometry and shot-by-shot dosimetry we are now in the position to extract relative biological efficiencies (RBE) vs. depth. We will describe the current status of the experimental program, present preliminary data on RBE vs. depth, and speculate on future developments.

Recently created, very low energy antiprotons are of great interest because of possible formation of ultraslow anti-hydrogen atoms [1,2]. In this work we compute the cross sections and rates of the anti-hydrogen and muonic anti-hydrogen atom three-body formation reactions at low and very low collision energies. The muonic anti-hydrogen is a bound state of an antiproton and a positive muon. In work [3] it was already pointed out that this exotic antimatter atom may also be of significant future interest in the field of matter-antimatter physics [3]. In the current work, a quantum-mechanical few-body method based on the coupled two-component Faddeev-Hahn-type equations is applied [4]. New results for low energy production reactions of anti-hydrogen and muonic anti-hydrogen atoms will be presented and discussed together with test results for the three-body muon transfer reactions from one hydrogen isotope to another heavier hydrogen isotope. 1. G.B. Andresen et al., (ALPHA Collaboration), Phys. Rev. Lett. 105, 013003 (2010). 2. G. Gabrielse et al., (ATRAP Collaboration), Phys. Rev. Lett. 106, 073002 (2011). 3. K. Nagamine, AIP Conf. Proc. 793, 159 (2005). 4. R.A. Sultanov and D. Guster, arXiv:1304.2434v1 [phys.atom-ph].

Antihydrogen is now routinely produced at CERN by overlapping clouds of positrons and antiprotons. The mechanisms responsible for antihydrogen formation (radiative capture and the three-body reaction) are both dependent on the temperature of the positrons (T_e), though with a different weight. Here we present a simple model of the behaviour of the positron temperature based on the main processes involved during antihydrogen synthesis, namely: antiproton-positron collisions, positron heating due to plasma expansion and cooling via the emission of synchrotron radiation. Simulations of the time evolution of T_e have been performed for the relevant working conditions of the CERN-AD experiments (but in particular ATHENA and ASACUSA) by changing the positron densities and the initial antiproton kinetic energies. A preliminary analysis comparing the experimental antihydrogen formation rates to those calculated using the present model results is also presented.

Frozen microspheres of hydrogen, so called pellets, are used as targets in the hadron physics experiment WASA (Forschungszentrum Juelich, Germany) [1] and will also be used in the future PANDA experiment at FAIR (GSI, Darmstadt, Germany) [2]. Pellets have a diameter of 25-30 micrometers. They are generated 2 - 3 meters above the interaction region, to which they travel inside a thin pipe (the space between pellet generation point and the interaction point is occupied by the particle detector system). The distance between the pellets is in the order of a few millimeters and they form a stream of a few millimeters in diameter. The interaction region is given by the overlap of the pellet stream and the accelerator beam and has a size of a few millimeters. One would like to know the interaction point more precisely, to have better possibility to reconstruct the particle tracks coming from the reaction point. One would also like to suppress background events that do not come from a pellet, but e.g. may occur in rest gas, that is present in the beam pipe. A solution is provided by the presented pellet tracking system, for which a prototype [3] has been developed at Uppsala Pellet Test Station (The Svedberg Laboratory, Uppsala, Sweden). The goal of the system is to track single pellets in order to know their position at the time of an interaction. The desired resolution is a few tenths of a millimeter. The tracking will be realized using lasers and fast line-scan (i.e. one dimensional) CCD cameras. The cameras, placed at different levels along the pellet stream, will measure pellets position and time of passage. Then, the information from many cameras will be put together to identify and reconstruct the track of each pellet. Information about the pellet position in the interaction region at the time of an interaction will be used in the analysis of the experimental data. To be useful, the tracking system must be highly efficient and provide tracking information for essentially all pellets that pass the interaction region. The design of such a system, simulation techniques and results will be presented. References: [1] WASA-at-COSY Collaboration: H.-H. Adam et al., arXiv:nucl-ex/0411038 (2004). [2] Physics Performance Report for PANDA: Strong Interaction Studies with Antiprotons, W. Erni et al., PANDA Collaboration, http://arxiv.org/abs/0903.3905v1 (2009). [3] H. Calen et al., Forschungszentrum Juelich IKP Annual Report, (2011).

During the past decades the nuclear and optical experiments to detect parity nonconservation (PNC) and hyperfine (hf) structure have progressed to the point where PNC amplitudes can be measured with accuracy on the level of a few % in certain heavy isotopes and significantly worse in some nuclei [1, 2]. Nowadays the PNC in the finite Fermi-systems has a potential to probe new physics beyond the Standard Model. Speech is about an electroweak interaction and PNC in heavy finite Fermi-systems. Here we systematically apply the formalism of the nuclear-QED many-body perturbation theory [3] to precise studying PNC effect in heavy atoms with account for the relativistic, nuclear and radiation QED corrections. The nuclear block of theory is presented by the relativistic mean field model (Dirac-Woods-Saxon model). Earlier an efficiency of this approach has been demonstrated in the precise calculation of the hyperfine structure constants, E1, M1 transition probabilities for some heavy atoms and heavy ions [3]. Here we present the calculated PNC radiative amplitudes for a set of nuclei (atoms): 133Cs, 173Yb, 205Tl, 223Ra with account of exchange-correlation, Breit, weak е-е interactions, QED and nuclear (magnetic moment distribution, finite size, neutron “skin”) corrections, nuclear-spin dependent corrections due to anapole moment, Z-boson ( (AnVe) current) exchange, HFS-Z exchange ((VnAe) current). The weak charge is found for 133Cs, 205Tl and firstly 173Yb and comparison with Standard Model is done. Using the experimental values E/beta=39mV/cm (Веrkeley, 2009; Tsigutkin et al) and our value 9.707 10(-10)eaB, one finds for 173Yb (Z=70, N=103) the weak charge value QW=-92.31, that is compared with the SM QW=-95.44. The received data are compared with known earlier and recent results by Flambaum etal, Johnson etal, Safronova et al. The nuclear spin- dependent PNC interactions due to nuclear anapole moment (ka contribution), Z- exchange interaction from nucleon axial-vector (AnVe) currents (k2), the combined hf and spin-independent Z exchange interaction from nucleon vector (VnAe) currents (khf) are studied. As example, in table 1 we present our results compared with the data on different contributions to the PNC spin-dependent contributions in the isotope of 133Cs (6s-7s), obtained by different groups Safronova etal, Haxton, Flambaum et al [1]. References: [1]. C Wood et al 1997 Science 275 1759; F Flaumaum, G.Ginges 2005 Phys.Rev. A 72 052115; M Safronova et al 2009 Nucl. Phys. A 827 411; W Haxton et al 2002 Phys. Rev. C 65 045502 [2]. W Johnson, J Sapirstein, S Blundell 1993 Phys. Scr. T46 184; V Dzuba, V Flambaum, M Safronova 2006 Phys. Rev. A 73 022112; V Shabaev et al 2005 Phys. Rev.A 72 062105 [3] O Khetselius 2009 Int. J. Quant. Chem. 109 3330; 2009 Phys.Scr. 135 014023 ; O Khetselius 2013 Advances in Theory of Quantum Systems in Chem. and Phys., Ser. Progress in Theor. Chemistry and Physics, eds. K. Nishikawa, J. Maruani, E. Brandas et al (Springer) 57 217(2012).

Detailed diagnostic of antiproton beams at low energies is required for essentially all experiments at the AD, but will be particularly important for the future ELENA ring and its keV beam lines to the different experiments. Many monitors have been successfully developed and operated at the AD, but in particular beam profile monitoring remains a challenge. A dedicated beam instrumentation and detector test stand has recently been setup at the AEgIS experiment. Located behind the actual experiment, it allows for parasitic use of the antiproton beam at different energies for testing and calibration. With the aim to explore and validate different candidate technologies for future low energy beam lines, as well as the downstream antihydrogen detector in AEgIS, measurements have been carried out using Silicon strip and pixel detectors, a purpose-built secondary emission monitor and emulsions. In this contribution results from these measurements and characterization of the different detector types with regard to their future use at the AD complex are presented. An outlook to future R&D plans is also given.

Hydrogen Lyman-α radiation (121.56 nm) is important because it allows for the excitation and detection of ground-state antihydrogen atoms by a one-photon process. The trapping of antihydrogen, recently reported by the ALPHA collaboration at CERN, has revived interest in Lyman-α lasers. In order to perform high precision tests of matter-antimatter symmetry violations or gravity-antimatter interactions with antihydrogen, laser cooling using the 1s-2p single photon transition is essential. We describe the implementation of a high power vacuum-ultraviolet (VUV) laser at the Lyman-α transition of antihydrogen.

At temperatures and densities relevant to current experiments antihydrogen is mainly formed through the three-body process pbar + e+ + e+ -> Hbar + e+. The state formed initially through this process is a Rydberg state, usually with a binding energy of only a few Kelvin. This state is fragile, and will not survive interaction with external fields or other particles, unless it is first stabilized through further collisions with positrons. Much more often, though, collisions with positrons will destroy the weakly bound antiatom, and only a very small fraction of the initially formed atoms will gain sufficient binding energy to reach a stable state. Simulations have shown that antiatoms are stable against collisional ionization once they have reached a binding energy greater than about 10 times the temperature of the positron plasma – the so called “bottleneck” [1]. In all experiments, the antihydrogen is formed in a static magnetic field with a strength ~1 Tesla. At positron-antiproton separations of a few microns, typical for the Rydberg antihydrogen in their initial states, magnetic forces will dominate. Thus the cyclotron energy of the positron is a conserved quantity, and the antiatom may remain bound even if its total energy (including the cyclotron energy of the positron) lies above the ionization threshold. On rare occasions, the positron passes close to the antiproton, which causes its cyclotron energy to rapidly change. The bound states with positive total energies are therefore metastable, as was pointed out by [2]. Through the inverse process, a metastable state can be formed in a positron-antiproton collision where the positron passes very close to the antiproton. We have simulated antihydrogen formation through classical particle-in-a-box calculations, in order to investigate the importance of formation and decay of these metastable states. We compare to similar calculations using the Guiding Center Approximation (GCA), where the cyclotron energy of the positrons is not allowed to change. We find that, though the formation of the initial antihydrogen state is usually well described by the GCA, the energy transfer is typically much larger in collisions where a metastable state is formed. These states are therefore more likely to survive further collisions. We find that inclusion of this mechanism has a significant impact on the formation rate of antihydrogen with binding energy of the order of the bottleneck energy. References [1] E. M. Bass and D. H. E. Dubin, Phys. Plasmas 16 (2009) 012101; M. E. Glinsky and T. M. O’Neil, Phys. Fluids B 3 (1991) 1279 [2] C. E. Correa, J. R. Correa and C. A. Ordonez, Physical Review E 72 (2005) 04640

A nonadiabatic description of the hydrogen-antihydrogen scattering is presented. The collisions are treated within the Coupled Rearrangement Channels method, which allows us to include different possible arrangement channels of the system under consideration. More over the proper asymptotic form of the continuum wave function is ensured, while the inner part of the wave function can still be described with square-integrable basis functions, as in the bound states calculations. The description of the rearrangement region is done in terms of the solutions to the discretized 4-body problem; hence it does not suffer from the limitations of the Born-Oppenheimer approach. Our method allows us to obtain a proper description of the 4-body system for any arrangement configuration and for any intermonomeric distance.The correct description of the asymptotic behavior of the total wave function is obtained by imposing proper boundary conditions on the functions describing the relative motion of the monomers at large separations. With these conditions the function describing the relative motion of the monomers is obtained by solving integro-differential equation, which automatically ensures a smooth transition between asymptotic and inner part of the total wave function. The scattering matrix is obtained form the shape of the wave function in the asymptotic region and further the scattering length for the elastic hydrogen-antihydrogen collisions can be calculated. The value of the scattering length obtained in the present work is 7.27 bohr, which is significantly different from earlier values obtained within the Born-Oppenheimer approximation.

Advancements in trapping and cooling antihydrogen pave a way to accurate spectral and gravitational measurements. Analysis of experiments require detailed knowledge and understanding of the nonlinear dynamics of antihydrogen atoms in magnetostatic traps in the presence of gravity. Perturbation theory yields insights and detailed simulations used to evaluate various techniques for measuring the ratio of the gravitational mass to the inertial mass of antihydrogen. These techniques are discussed and compared. Theoretical considerations and numerical simulations suggest that stochasticity may play a crucial role in some experimental techniques. Chaotic particle motion is also shown to facilitate laser cooling of trapped antiatoms. Different approaches to inducing orbit stochasticity are discussed.

We investigate the presence of thermodynamic instabilities in a hot and dense nuclear medium where a phase transition from a gas of massive hadrons to a nearly massless baryon, antibaryon plasma can take place. The analysis is performed by requiring the global conservation of baryon number and zero net strangeness in the framework of an effective relativistic mean field theory with the inclusion of the Delta(1232)-isobars, hyperons and the lightest pseudoscalar and vector meson degrees of freedom. Similarly to the low density nuclear liquid-gas phase transition, we show that such a phase transition is characterized by both mechanical instability (fluctuations on the baryon density) that by chemical-diffusive instability (fluctuations on the strangeness concentration). It turns out that, in this situation, phases with different values of antibaryon-baryon ratios and strangeness content may coexist.

for the PANDA collaboration. The creation mechanism of quark-antiquark pairs and their arrangement to hadrons can be studied by measuring the reactions of the type antiproton+proton -> antibaryon+baryon. According to the Okubo-Zweig-Iizuka rule, all processes with disconnected quark lines are suppressed. By comparing several reactions involving different quark flavours the OZI rule, and its possible violation, can be tested for different levels of disconnected quark-line diagrams separately. Furthermore, the parity violating weak decay of most ground state hyperons introduces an asymmetry in the distribution of the decay particles. As a consequence, the direction of flight of the decay products of the hyperon is related to the polarisation of the hyperon. This is quantified by the decay asymmetry parameter and gives access to spin degrees of freedom, e.g. the hyperon polarisation and the spin correlation of the hyperon and the antihyperon . One open question is how these observables related to the underlying degrees of freedom of the production mechanism. All strange hyperons, as well as single charmed hyperons, are energetically accessible in the PANDA experiment at HESR, FAIR. A systematic investigation of these reactions will shed new light on single and multiple strangeness production and its dependence on spin observables. Above 2 GeV/c , PANDA will break new ground since no differential distributions and spin observables have been studied in this region so far. Simulations show that the differential cross sections as well as the spin observables can be well reconstructed with PANDA, both for strange- and single charmed hyperon channels. The results will be presented in this poster.

A relativistic operator approach, based on the unified operator perturbation theory and relativistic energy formalism [1], is applied for studying resonant phenomena in the low-energy heavy-nuclei collisions accompanying the electron-positron pair production (EPPP) process and treating the compound nucleus in an extreme electromagnetic (electric) field. As it is known, a narrow e+ line in the positron spectra obtained from heavy ions collisions near the Coulomb barrier is existed (see, e.g.,[1,2]). In our approach the positron spectrum narrow peaks as a spectrum of the resonance states of compound super heavy nucleus are treated. Resonance phenomena in the nuclear system lead to structurization of the positron spectrum produced. To calculate the EPPP cross-section we used the modified versions of the relativistic energy approach, based on the S-matrix Gell-Mann and Low formalism [1]. The nuclear and electron subsystems are considered as two parts of the complicated system, interacting with each other through the model potential. The nuclear system dynamics is treated within the Dirac equation with an effective potential. All the spontaneous decay or the new particle (particles) production processes are excluded in the 0th order. The calculation results for cross-sections at different collision energies (non-resonant energies and resonant ones), corresponding to energies of resonances of the compound 238U+238U, 232Th+250Cf and 238U+248Cm nuclei are presented. Calculation with the different nuclear potentials is carried out and shows principally the same physical picture, however using the two-pocket nuclear potential in comparison with the one-pocket one [2] leads to an appearance of a few new peaks. At last, we generalize a developed approach to describe relatively low-energy collision of the heavy ion with light projectiles (proton, antiproton). References 1. A.V.Glushkov, Low Energy Antiproton Phys. (AIP). 2005. V.796.P.206; J.Phys.: CS. 2012. V.397. P.012011; Quantum Systems in Chemistry and physics, Progress in Methods and Applications, Eds. K. Nishikawa et al (Speinger). 2013. V. 26. P.231; A.V.Glushkov et al, Nucl.Phys.A. 2004. V.734S, 21; Int. J. Mod. Phys.A. Nucl.Phys. 2009. V. 24. P.611. 2.P. Kienle, Phys.Scripta. 1993. V.T46. P.81; J.Reinhardt, U.Muller, W.Greiner, Z.Phys.A.1981.V.A303.P.173; V.Zagrebaev, W.Greiner, J. Phys. G. 2007.V.34.P.1; 2002. V.31.P.825.

The ASACUSA collaboration aims to measure the ground state hyperfine splitting of anti hydrogen with a Rabi like experiment. In the experimental setup a beam of partially polarized anti hydrogen atoms enter a microwave cavity which induces a spin flip. After that a superconducting sextupole magnet is used to analyze the spins of the particles. Finally our anti hydrogen detector identifies the antimatter atoms. Since the properties of the cavity and the sextupole magnet have to be crosschecked, we want to measure the very well known ground state hyperfine splitting of the hydrogen atom with this equipment. In this work we present an apparatus that we use to produce a spin polarized beam consisting of atomic hydrogen atoms, which we detect with a quadrupole mass spectrometer (QMS). Hydrogen molecules are dissociated by a microwave induced discharge. The particles enter a differentially pumped vacuum system consisting of four chambers. With the help of a skimmer and apertures a beam is formed. This beam is polarized with permanent sextupole magnets. For the detection of the formed hydrogen we use a cross beam QMS with a lock in amplifier. With this apparatus the experiment described before will be performed this summer at CERN. Authors: M. Diermaier, P. Caradonna, M. Wolf, O. Massiczek, B. Wünschek, N. Dilaver, B. Kolbinger, C. Malbrunot, C. Sauerzopf, K. Suzuki, J. Zmeskal, E. Widmann Stefan-Meyer-Institut für subatomare Physik, der Österreichischen Akademie der Wissenschaften, Boltzmanngasse 3, A-1090, Austria

The PANDA (AntiProton ANnihilation at DArmstadt) experiment is one of the key projects at the future Facility for Antiproton and Ion Research, which is currently under construction at GSI, Darmstadt. The PANDA experiment will perform precise studies of antiproton-proton annihilations and reactions of antiprotons with nucleons of heavier nuclear targets. Particles emitted at angles covering the range from 5° to 22°, which are not covered fully by the central tracking detectors (STT and MVD), will be tracked by three planar GEM stations placed down-stream of the target. Each station consists of double planes with two projections per plane. The stations will be equipped with gaseous micro-pattern detectors based on Gas Electron Multiplier (GEM) foils as amplification stages. The chambers have to sustain a high counting rate of particles peaked at the most forward angles due to the relativistic boost of the reaction products as well as due to the small angle proton-antiproton elastic scattering. Creation and propagation of an electron avalanche and its collection by a pad plane in a GEM detector has been simulated with the Garfield program. The influence of the size of the pad strips on the position resolution given by the distribution of charge in space at the readout plane has been investigated. It is determined by two main processes: drift of electrons in the electric field and their diffusion in the gas filling the detector. The time-dependence of the signal at the readout plane has been simulated to study the detector performance in high-rate environment.

The eta meson production process can be studied via measurements of the analyzing power, Ay, which may be understood as a measure of the relative deviation between the differential cross section with and without polarized beam. So far, these observables have been determined only for a few excess energies and with very low statistics. Therefore, the measurement of the (vec)pp->pp eta reaction was performed at WASA-at-COSY detector and the experiment was conducted for beam momenta of 2026 MeV/c and 2188 MeV/c. Protons from the (vec)pp->pp reaction are registered in the forward and the central part of the detector. Gamma quanta from the eta decay are detected in the Electromagnetic Calorimeter. Additionally, in order to monitor the beam polarization, the luminosity and the detector performance, the (vec)pp->pp reaction was measured as well, and in order to control effects caused by potential asymmetries in the detector setup, the spin of the proton beam was flipped from cycle to cycle. The status of the analysis will be presented and discussed.

The central electromagnetic calorimeter (EMC) of the PANDA detector consists of a barrel part with 11 360 PWO crystals of 11 different shapes, a forward end cap with 3864 crystals and a backward end cap with 592 crystals. The complete EMC will sit in a solenoid field, which rules out the use of photomultiplers as light sensors. Avalanche Photo Diodes (APDs) will be used for the barrel part to detect the scintillation light. For the forward end cap a faster readout is probably needed, due the larger rate of photons/particles per crystal. So called Vacuum Photo Triodes (VPTs) or Vacuum Photo Tetroides (VPTTs) are proposed to use here, at least for the more central part. In order to fully reconstruct events in the PANDA detector a high efficiency is essential for detecting individual gamma rays. In the Technical Design Report of the EMC [1] it is specified that an energy threshold not exceeding 3 MeV for individual crystals and an energy resolution of 16.4% at 15 MeV and 8.2 % at 60 MeV should be obtained. In a series of experiments at the tagged photon facility at MAX-Lab, Lund we have studied the response of forward end cap crystals to gamma rays in the low energy part of the spectrum, approximately between 10 and 60 MeV. Here we will present results for the energy resolution using VPTs and APDs as light sensors and compare these to results for photomultipliers.

The principal aim of the ALPHA experiment at CERN is to trap cold atomic antihydrogen, study its properties, and, ultimately, perform precision comparison between hydrogen and antihydrogen atomic spectra. Recently, several important milestones have been achieved, including long confinement times of antihydrogen atoms, the first spectroscopic measurements of the antihydrogen atoms and first application of a new technique to measure the gravitational mass of antihydrogen. The main experimental tool for the antihydrogen detection in the experiment is the ALPHA silicon vertex detector. The detector consists of three concentric barrels of 144 double sided silicon sensors and provides information on the time evolution of antiproton plasmas and individual annihilation events. The characteristics of the detector will be presented along with an application of the precise reconstruction of the annihilation vertex and its importance in the anti-matter gravity search.

The ELENA ring will decelerate the 5.3 MeV antiprotons from the AD (Antiproton Decelerator) to an energy of just 100 keV with the aim to increase by one or two orders of magnitude the number of usable antiprotons for the physics experiments. An additional experimental area will also allow the extension of the low energy antiproton physics program to new experiments. Beam cooling will be applied at an intermediate and extraction energies in order to obtain high density bunches which will be transported to the experiments via a new electrostatic beam transfer line. The expected main performance limitations such as intra-beam scattering and tune shift due to space charge will be addressed and the status of some the most important sub-systems; ring magnets, electron cooling, beam instrumentation and vacuum system, will be reported.

*AD: Antiproton Decelerator **ELENA: Extra Low Energy Antiprotons ELENA will lower the energy of AD antiprotons from 5MeV to 100keV, thus increasing by a factor of up to 100 the number of antiprotons usable by the experiments. The AD infrastructures must be adapted to cope with this new machine, new experiments and another 20 years of brilliant prospects. To fit the ELENA ring in the already crowded AD hall, old delicate kicker generators must be relocated to a new annex building, existing and new services and racks must be re-arranged also at height, preserving access and maintenance capabilities. The ELENA beam will be delivered to existing experiments via new transfer lines without compromising the possibility to maintain a visitors path to this very popular place at CERN. New experimental areas being designed to house the new projects (GBar, BASE), and re-arrangement for future experiments (cleaning rooms relocation in the new annex building, control rooms installation in a separate building with a cafeteria and a conference room) are also detailed.

for the PAX collaboration. A polarized antiproton beam to be used at FAIR would give access to a completely new research field in the study of the strong interaction utilizing polarization technology as a highly selective tool. One of the main objectives is the unique possibility to access model independent and directly the transversity of the proton through Drell-Yan events generated in double polarized proton-antiproton interaction. In order to reach the goal of the production of a useful polarized antiproton beam, the PAX Collaboration has undertaken the task to design and commission a dedicated experimental facility. This process includes the submission of a proposal to measure the antiproton-proton spin-dependent cross section at the AD ring [1]. To meet the technical challenges of installing the developed facility in the AD ring a proton-proton spin-filter experiment has been done at the Cooler Synchrotron COSY. The experiment successfully proved the validity of the spin-filter method to polarize a stored beam in situ and led to a deepened understanding of the inherent machine properties that need optimizing for the process to be effective [2]. An overview of the achieved milestones and the planned PAX experiments will be given. [1] Technical Proposal for the Measurement of the Spin-Dependence of the pbar-p Interaction at the AD-Ring, PSC-2009–012; SPSC-P-337. [2] W. Augustyniak et al., Phys. Lett. B 718 (2012) 64.

We study the pair-production of heavy mesons in proton-antiproton annihilations within a perturbative QCD motivated framework [A.T. Goritschnig, B. Pire and W. Schweiger, Phys.Rev. D87 (2013) 014017]. In particular we investigate pbar p to pbar D^0 D^0 within a double handbag approach, where the hard process ud ubar dbar to cbar c factorizes from soft matrix elements of c q q operators. The soft matrix elements can be parameterized by transition distribution amplitudes, which are off-diagonal in flavor space. The transition distribution amplitudes are modelled by representing them as overlaps of light-cone wave-functions (where we have treated the proton within a quark-diquark picture). We obtain rather robust model results for p pbar -> D^0bar D^0 cross sections, which are also expected to be measured at the future PANDA detector at GSI-FAIR.

Hypernuclear research will be one of the main topics addressed by the PANDA experiment at the planned Facility for Antiproton and Ion Research FAIR at Darmstadt (Germany). Thanks to the use of stored antiprotons beams, copious production of double lambda-hypernuclei is expected at the PANDA experiment, which will enable high precision gamma spectroscopy of such nuclei for the first time, and consequently a unique chance to explore the hyperon-hyperon interaction. In comparison to previous experiments, PANDA will benefit from a novel technique to assign the various observable gamma-transitions in a unique way to specific double hypernuclei by exploring various light targets. Nevertheless, the ability to carry out unique assigments requires a devoted hypernuclear detector setup. This consists of a primary nuclear target for the production of Xi + Xibar pairs, a secondary active target for the hypernuclei formation and the identification of associated decay products and a germanium array detector to perform gamma spectroscopy. Moreover, one of the most challenging issues of this project is the fact that all detector systems need to operate in the presence of a high magnetic field and a large hadronic background. Accordingly, the need of an innovative detector concept will require dramatic improvements to fullfil these conditions and that will likely lead to a new generation of detectors. In the present talk details concerning the current status of the activities related to the detector developments for this challenging programme will be given. Among these improvements is the new concept for a cooling system for the germanium detector based on a electro-mechanical device. Additionally, it will be shown how the use of techniques based on pulse digital shape analysis can be applied to restore the energy resolution and line shape of radiation damaged germanium crystals. Furthermore, since the momentum resolution of low momentum particles is crucial for the unique identification of hypernuclei, an analysis procedure for improving the momentum resolution in few layer silicon based trackers is presented.

At Panda project, they are planning to produce many double Lambda hypernuclei using p-bar beam. Recently, I performed five-body calculation of Be11LL with alpha alpha +n+2Lambda five-body calculation. In the conference, I will report the calculation and mention what is important to study double Lambda hypernuclei. And I also show the four-body calculation of H4LL using Lambda-Lambda -Xi N coupling, which is important to study the H-dibaryon system.

With the study of hadron and meson production in antinucleon-nucleus reactions a broad spectrum of final particle configurations and physics phenomena becomes accessible. The fundamental interactions of the underlying sub-processes are of high interest by itself. The approach is directed towards investigations of non-strange meson production and strangeness channels, ranging from elementary processes in antiproton-proton interactions and antiproton-nucleus collisions to the production of hypernuclei. We are investigating coherent meson production in antiproton-nucleus reactions, intended as exploratory studies for the PANDA experiment and, if realized at a later stage of FAIR, also for the nuclear structure-oriented use of high energy antiprotons aimed for by the AIC proposal. Coherent reactions have the distinct advantage of a full quantum mechanical treatment of all parts of the production process. As a concrete and typical example we treat explicitly the case of two pion production. Two different reaction mechanisms are presented including initial and final state interactions. The underlying fundamental antinucleon-nucleon Nbar N and pion-nucleon pi N interactions enter into the optical potentials, which are obtained with Hartree-Fock-Bogoliubov nuclear densities. Existing approaches to pion nucleus interactions have been extended to higher energies beyond the Delta(1232)-resonance. A phenomenological ansatz for the antinucleon-nucleon interaction, describing the whole energy range up to pLab=15 GeV/c is presented. First results for pion and rho-meson production on nuclei are presented. Cross sections are shown for the elementary processes and future experiments at FAIR. Partially supported by DFG grant Le439/8-2 and HICforFAIR

The ASACUSA CUSP collaboration at the Antiproton Decelerator of CERN is planning to measure the ground-state hyperfine splitting of antihydrogen using an atomic spectroscopy beamline. Antihydrogen is the simplest atom consisting entirely of antimatter. Since its matter counterpart is one of the most precisely measured atoms in physics, a comparison of antihydrogen and hydrogen could provide one of the most sensitive tests of CPT symmetry. The setup consists of a source of partially polarized antihydrogen atoms [1,2] emitted toward a radiofrequency spin-flip cavity with its resonance frequency tuned to the hyperfine transition. A superconducting sextupole magnet serves as spin analyser before the detection of the atoms in an antihydrogen detector [3]. Monte Carlo simulations show that the antihydrogen ground-state hyperfine splitting can be determined in such a beam setup at a relative precision of 0.1ppm which would already provide one of the best test of CPT. My talk will present the latest developments on the spectroscopy apparatus downstream of the antihydrogen polarizing source, the coming years program to achieve the above mentioned precision as well as a short overview of the atomic hydrogen beamline developed to test the performance of the spectroscopy apparatus during the CERN accelerator shutdown LS1. [1] Y. Enomoto et al., Phys. Rev. Lett. 105, 243401 (2010). [2] N. Kuroda et al., Hyperfine Interact 209:3541 (2012). [3] E. Widmann et al., Hyperfine Interactions doi:10.1007/s10751-013-0809-6 (2012). Co-authors: C .Sauerzopf(1), P. Caradonna(1), M. Diermaier(1), N. Dilaver(1), S. Federmann(1,2), B. Kolbinger(1), M. Leali(3), V. Mascagna(3), O. Massiczek(1), K. Michishio(4), T. Mizutani(5), A. Mohri(6), D. Murtagh(6), H. Nagahama(5), Y. Nagashima(4), Y. Nagata(6), M. Ohtsuka(5), B. Radics(6), S. Sakurai(7), K. Suzuki(1), S. Tajima(5), H.A. Torii(4), S. Van Gorp(6), L. Venturelli(3), M. Wolf(1), B. Wunschek(1), ,J. Zmeskal(1), N. Zurlo(3), E. Lodi-Rizzini(3) , H. Higaki(7), Y. Kanai(6), N. Kuroda(5), Y. Matsuda(5), S. Ulmer(6), E. Widmann(1), Y. Yamazaki(6) (1) Stefan-Meyer-Institut fur subatomare Physik, der Osterreichischen Akademie der Wissenschaften, Boltzmanngasse 3, A-1090, Austria (2) CERN, 1211 Geneva, Switzerland (3) Dipartimento di Chimica e Fisica per lIngegneria e per i Materiali ,Universit di Brescia & Istituto Nazionale di Fisica Nucleare, Gruppo Collegato di Brescia, 25133 Brescia, Italy (4) Department of Physics,Tokyo University of Science, Kagurazaka, Shinjuku,Tokyo162-8601, Japan (5) Graduate School of Arts and Sciences, University of Tokyo, Komaba, Meguro, Tokyo 153-8902, Japan (6) RIKEN Advanced Science Institute, 2-1Hirosawa, Wako,Saitama 351-0198, Japan (7) Graduate School of Advanced Sciences of Matter, Hiroshima University, Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8530, Japan

The ASACUSA collaboration has been making a path to realize high precision microwave spectroscopy of ground-state hyperfine splitting of antihydrogen atom in flight for a stringent test of the CPT symmetry. For our physics goal, an efficient extraction of a spin polarized antihydrogen beam is essential. In 2010, we have succeeded in synthesizing our first cold antihydrogen atoms employing a CUSP trap consisting of a superconducting anti-Helmholtz coil and a stack of multiple ring electrodes[1]. This was achieved with our antiproton accumulator, MUSASHI, and a positron accumulator. However the rate of antihydrogen synthesis was limited by a low accumulation efficiency of positrons. In addition, the total number of synthesized antihydrogen was found to be suppressed[1]. To proceed the next step, we made improvements, like for example a modified positron source for rapid experimental cycle and a new mixing scheme to prolong the reaction period. An antihydrogen beam detector has also been developed. It was comprised of an inorganic single-crystal scintillator and surrounding plastic scintillator plates. We report the recent results of antihydrogen synthesis and attempts of an anti-atomic beam production. Ref.[1] Y. Enomoto et al., Phys. Rev. Lett. 105 (2010) 243401.

One may wonder why is physics at the scale of a fermi still interesting, when the LHC microscope is tuned to a world a thousand times smaller? Confinement means the universe of quarks and gluons (or even squarks and gluinos) can only be glimpsed through a colourless haze of hadrons. This we need to understand. How this world of hadrons, their spectrum, their structure and dynamics, is being explored in unprecedented detail at the scale of a few GeV with precision detectors at accelerator facilities and on the lattice with accelerated computing architectures will be reviewed. This is teaching us about how QCD shapes and colours most of the visible universe.

for the PANDA collaboration. The proton electric and magnetic form factors in the time-like region (TL-FF) could offer a much richer set of information if compared to the one that can be accessed via the space-like form factors (SL-FF), for which several controversial data are present. An independent experimental determination of the TL-FF would allow for: - a global description of the hadronic TL- and SL-FF via analytic continuation techniques, and hence the development of realistic models able to describe the nucleon structure in the whole kinematical region; - a selection among the (vastly) different theoretical predictions available in the literature. Due to the high precision needed and the involved energies and transfer momenta, radiative corrections due to real and virtual photon emission from the charged particles (in particular electrons) must be taken carefully into account. The experimental scenario constituted by the PANDA spectrometer on the HESR ring (part of the forthcoming FAIR facility) would allow to access and to perform an independent evaluation of the TL electric and magnetic proton FF, with unprecedented luminosities in annihilation processes and transferred momenta large enough (q^2 up to 25 GeV^2) to probe the asymptotic FF behaviour.

In the year 2010 a subgroup of the PANDA Collaboration started with the first Partial Wave Analysis (PWA) activities. The main objective is to develop a powerful, user-friendly and highly modular PWA software package with the ability to provide amplitudes in different formalisms and to support analyses of all physics cases at PANDA and also of data from other hadron spectroscopy experiments. After a brief overview of the present status of the software package the first PWA results obtained with the existing tools are presented. These analyses are mainly focused on important aspects of antiproton proton annihilation processes within the energy range accessible with the PANDA experiment. For this purpose Crystal Barrel LEAR data are currently under investigation in order to gain a deeper insight to the production mechanisms of vector mesons. In addition analyses for the identification of resonances in radiative J/ψ and ψ(2S) decays from BES III data are summarized.

CRYRING has until recently been operating at the Manne Siegbahn Laboratory (MSL) in Stockholm for in-ring atomic physics experiments. Since its operation was decided to be determined, it has been chosen by the FLAIR collaboration as the central installation of the FLAIR facility, decelerating both highly charged ions and antiprotons for either extraction to experiments or further deceleration in the HITRAP or USR facilities. The necessary modifications of CRYRING for both fast and slow extraction have been implemented by MSL and CRYRING has been transported to GSI last year for installation already at the existing ESR storage ring, where it will be commissioned and start operation with highly charged ions. The modified design of CRYRING allows for both slow and fast extraction in an energy range of 30 MeV to 300 keV and, if connected to an antiproton source to be built at FAIR, would be a unique source of both pulsed and continuous low-energy antiproton beams. The talk will describe the physics potential of such an installation.

for the PANDA collaboration. The PANDA experiment will make use of cooled antiproton beams of unprecedented quality that will be available at the Facility for Antiproton and Ion Research (FAIR) in Darmstadt, featuring up to 10^11 antiprotons and momentum in the 1.5 ÷ 15 GeV/c range at the High Energy Storage Ring (HESR) on whose the PANDA apparatus will occupy one of the straight sectors. The envisaged physics program using hydrogen target includes: spectroscopy of charmonium and of open charm mesons, search for gluonic excitations, spectroscopy of charmed baryons and study of nucleaon structure by measurement of time-like form factors, Drell-Yan and generalized parton distributions. Using nuclear targets it is planned to investigate: modification of the properties of mesons embedded in nuclear medium and properties of double hypernuclei. This rich physics program asks for a general purpose apparatus able to detect charged and neutral particles over a wide emission angle with the challenge request of a triggerless data acquisition. The study of several physics processes requires particle identification including pions, kaons, protons as well as electrons and muons in a large momentum range from about 200 MeV/c up to 10 GeV/c, while the momentum resolution is less than 2%. The reconstruction of charmed mesons can be pursued with a vertex detector with a spatial resolution better than 100 um. Photons from many physics channels ask for low photon threshold, few MeV, and large dynamic range, up to 10 GeV/c, for the electromagnetic calorimeter. The design of such apparatus is an advanced stage and the R&D phase is approaching the end, as resulted by the most of the TDRs already completed or under writing. In addition the production phase is already started for the Electromagnetic Calorimeter. Subsystems of PANDA including magnets and target, tracking detectors, particle identification detectors, calorimeters will be described.

The Ultra-low energy electrostatic Storage Ring (USR) at the future Facility for Low-energy Antiproton and Ion Research (FLAIR) will provide cooled beams of antiprotons in the energy range between 300 keV down to 20 keV. Based on the original design concept developed in 2005, the USR has been completely redesigned over the past few years by the QUASAR Group. The ring structure is now based on a 'split achromat' lattice. This ensures compact ring dimensions of 10 x 10 m, whilst allowing both, in-ring experiments with gas jet targets and studies with extracted beams. In the USR, a wide range of beam parameters shall be provided, ranging from very short pulses in the nanosecond regime to a coasting beam. In addition, a combined fast and slow extraction scheme will be featured that allows for providing external experiments with cooled beams of different time structure. Detailed investigations into the dynamics of low energy beams, including studies into the long term beam dynamics and ion kinetics, beam life time, equilibrium momentum spread and equilibrium lateral spread during collisions with an internal target were carried out. This required the development of new simulation tools to further the understanding of beam storage with electrostatic fields. Furthermore, studies into beam diagnostics methods for the monitoring of ultra-low energy ions at beam intensities less than 106 were carried out. This includes instrumentation for the early commissioning of the machine, as well as for later operation with antiprotons. In this contribution, the technical design of the USR will be presented with an emphasis on the expected beam parameters available to the different experiments at FLAIR.

for the PANDA collaboration. The PANDA experiment at the future FAIR facility investigates antiproton induced collisions on a proton or nuclear target with unprecedented precision and luminosity to study fundamental questions in QCD in the non-perturbative regime with antiproton-beam momenta between 1.5GeV/c and 15GeV/c. The central Straw Tube Tracker (STT) in the 2 Tesla solenoid target spectrometer features a high spatial reconstruction of charged particles in a broad momentum range together with a measurement of their specific energy-loss for a particle identification in the low momentum region below about 1 GeV/c. The high antiproton-proton annihilation rate of about 2x10^7/s and the very rich spectrum of quite different reaction channels and topologies require a continuous data-acquisition with fast and efficient online track and event reconstructions. In this talk the design of the STT, main properties and current status of the construction are discussed.

The PANDA-Experiment at the future FAIR facility in Darmstadt will implement a Micro-Vertex-Detector (MVD) and a large-volume Straw Tube Tracker (STT) around the target interaction region together with a set of GEM disks for the charged particle tracking within a 2 T solenoidal magnetic field. The STT is a gas based detector which is comprised of 4636 cylindrical drift chambers (straw tubes) of 1 cm diameter and 150 cm length, filling an almost cylindrical volume from 16 cm up to a radius of 42 cm around the MVD. At PANDA a continuous readout mode of the detectors is required due to the broad range of different event topologies and the very high interaction rate of 2*10^7 annihilations per second. Due to the similar topology of the interesting physics events and the hadronic background, PANDA will use an online event filter to distinguish signal events from background. In contrast to a traditional trigger system, the online event filter will use high level information such as particle identification, momentum and invariant mass information to identify the physics events. Tracking information is a prerequisite for all of these, therefore we attempt to reconstruct all tracks in a continuous online tracking scheme. The interplay of different tracking algorithms is required for an optimized reconstruction of the multitude of possible event topologies. One method of track finding is based on the identification of hit triplets within a certain time window. It is then particularly simple to analytically calculate the circle parameters of the track helix' projection into the xy-plane. We will present the triplet method in detail as well as studies on its applicability under the PANDA operating conditions. This work was supported by BMBF, HIC4FAIR and Forschungszentrum Jülich GmbH.

The Einstein classical Weak Equivalence Principle states that the trajectory of a particle is independent of its composition and internal structure when it is only submitted to gravitational forces. This fundamental principle has never been directly tested with antimatter. However, theoretical models such as supergravity may contain components inducing repulsive gravity thus violating this principle. The GBAR project (Gravitational Behaviour of Antihydrogen at Rest), accepted at CERN, proposes to measure the free fall acceleration of ultracold neutral antihydrogen atoms in the terrestrial gravitational field. The experiment consists in preparing antihydrogen ions (one antiproton and two positrons) and sympathetically cool them with Be+ ions to a few 10 mK. The ultracold ions will then be photo-ionized just above threshold, and the free-fall time over a known distance measured. I will describe the project, the accuracy that can be reached by standard techniques, and discuss possible improvements using quantum reflection of antihydrogen on surfaces to use quantum methods of measurements.

ALPHA has searched for a propensity for antihydrogen atoms to fall downward when released from the ALPHA trap. We find that we can reject ratios of the gravitational to inertial mass of antihydrogen greater than approximately 100 at a statistical significance level of 5%. A similar search places somewhat tighter bounds on a negative gravitational mass, i.e., on antigravity. The technique utilizes the spatial and temporal resolution of our detector and the analysis involves detailed numerical simulations of antihydrogen dynamics in the trap. We have carefully studied both the systematics and statistics of this methodology. We find that with cooled antihydrogen atoms and detailed knowledge of the magnetic field profile, this technique has the potential to bound the gravitational to inertial mass ratio to values near unity.

for the AEgIS collaboration. Antihydrogen holds the promise to test, for the first time, the universality of free-fall with a system composed entirely of antiparticles. The AEgIS experiment at CERN’s antiproton decelerator aims to measure the gravitational interaction between matter and antimatter by measuring the deflection of a beam of antihydrogen in the Earth’s gravitational field (gbar). The principle of the experiment is as follows: cold antihydrogen atoms are synthesized in a Penning-Malberg trap and are Stark accelerated towards a moiré deflectometer, the classical counterpart of an atom interferometer, and annihilate on a position sensitive detector. Crucial to the success of the experiment is the spatial precision of the position sensitive detector. We propose a novel free-fall detector based on a hybrid of two technologies: nuclear emulsions, which have an intrinsic spatial resolution of 50 nm but no temporal information, and a silicon strip tracker to provide timing and positional information. In 2012 we tested emulsion films in vacuum with 5 MeV antiprotons from CERN's antiproton decelerator. The annihilation vertices could be observed directly on the emulsion surface using the microscope facility available at the University of Bern. The annihilation vertices were successfully reconstructed with a resolution of 1-2 microns on the impact parameter. If such a precision can be realized in the final detector, Monte Carlo simulations suggest of order 500 antihydrogen annihilations will be sufficient to determine gbar with a 1% accuracy. We will present current research towards the development of this technology for use in the AEgIS apparatus and present prospects for the realization of the final detector.

The CPT symmetry is a fundamental cornerstone of the Standard Model. It predicts the exact equality between the properties of particles and their antimatter counterparts. Thus, precise experimental comparisons of matter/antimatter properties provide stringent tests of the CPT symmetry. The goal of our experiment is a precise CPT test with baryons. We aim at a direct measurement of the magnetic moment of a single isolated proton in a Penning trap at a relative precision of at least 10-9. All experimental methods can directly be applied to the antiproton. In a Penning trap the magnetic moment µp can be determined by the measurement of the Larmor frequency νL and the cyclotron frequency νc of the proton. The frequency ratio νL/νc=µp/µN yields µp in units of the nuclear magneton µN. νc can readily be determined via image current detection of the three eigenfrequencies of the trapped proton. The Larmor frequency νL is obtained by application of the continuous Stern-Gerlach effect. In this scheme an inhomogeneous magnetic field is superimposed to the trap, which couples the spin magnetic moment of the proton to its axial motion. A spin flip causes an axial frequency shift of about 170 mHz out of 740 kHz. By measuring the spin flip rate as a function of an applied drive frequency, νL is obtained. Based on a statistical detection of spin flips in the inhomogeneous magnetic field [1] we measured the magnetic moment of the proton with a precision of 8.9 ppm [2]. Another group achieved 2.5 ppm in the case of the proton [3] and 4.4 ppm in the case of the antiproton [4] using a similar setup. However, the precision of these results is limited by the superimposed inhomogeneity of the magnetic field, which significantly broadens the Larmor resonance line. The precision can be improved by orders of magnitude by using the double-Penning trap technique. In this method the frequency measurements of νc and νL, and the spin state analysis by means of the magnetic inhomogeneity are spatially separated to two traps, a precision trap and an analysis trap, respectively. In the PT the magnetic field is about a factor of 100000 more homogeneous than in the AT. This reduces the line with of the Larmor resonance drastically. The double-Penning trap technique requires that single spin flips can be resolved, which was so far not possible with nuclear spins. However, with a significantly improved apparatus we recently achieved this challenging goal by using Bayesian statistics [5]. This enabled the first demonstration of the double trap technique with a single proton [6], which is a major step towards a high precision measurement of the proton/antiproton magnetic moment at the ppb level. In the talk an overview on the experimental status is presented and an outlook towards the first high precision measurement of the proton magnetic moment by means of the double trap technique is given. [1] S. Ulmer et al., Phys. Rev. Lett. 106, 253001 (2011). [2] C. C. Rodegheri et al., New J. Phys. 14, 063011 (2012). [3] J. DiSciacca et al., Phys. Rev. Lett. 108, 153001 (2012). [4] J. DiSciacca et al., Phys. Rev. Lett. 110, 130801 (2013). [5] A. Mooser et al., Phys. Rev. Lett. 110, 140405 (2013). [6] A. Mooser et al., submitted to Phys. Lett. B.

The GBAR experiment (Gravitational Behaviour of Antihydrogen at Rest) [1,2] was recently accepted at CERN at its Antiproton Decelerator facility. The aim of the experiment is to perform the free fall of antihydrogen atoms (Hbar) to test the weak equivalence principle for antimatter. In order to reduce the uncertainty on the initial Hbar velocity, ultra-cold antihydrogen atoms of a few neV are required. The key idea of the GBAR experiment is to use Hbar+ ions that can be cooled with techniques established for ultra-cold atoms [see talk by Paul Indelicato at this conference]. The Hbar+ ions will be produced from collisions between keV antiprotons (pbar) and a positronium (Ps) cloud through two successive reactions: (1) pbar + Ps(n_p,l_p) -> Hbar(n_h,l_h) + e- (3-body reaction) (2) Hbar(n_h,l_h ) + Ps(n_p,l_p) -> Hbar+ + e- (4-body reaction). A theoretical study of reactions (1) & (2) has been undertaken in order to optimise the Hbar+ production by choosing accurately the energy of the pbar beam and the Ps excited state (n_p,l_p). An exhaustive set of cross sections has been obtained for both reactions, from Ps(1s) to Ps(3d) and considering Hbar states up to n_h=4. Contrary to reaction (2) [3,4], reaction (1) has been already widely studied, mainly through the reverse reaction of Ps formation (for instance in [5]), but for the sake of theoretical consistency, it has been decided to apply the same theoretical model, namely the Continuum Distorted Wave – Final State model (CDW-FS), to compute the cross sections of both reactions at the same level of approximation. [6] Concerning reaction (2), the highly correlated system formed by Hbar+ has been treated carefully, using three different wave functions proposed for H-. [7,8] In the case of reaction (1), the results show an enhancement of the Hbar production toward low pbar kinetic energies, when n_h and n_p increase. This agrees with experimental data [9] and previous calculations [5]. For reaction (2), a nearly resonant behaviour close to threshold is observed for excited positronium, when Hbar is in its ground state. For both reactions, above 1 keV pbar energy, the highest cross sections are obtained with Ps(2p). In order to estimate the Hbar+ production in the reaction chamber of the GBAR experiment and optimise other experimental parameters such as laser power for Ps excitation and delays between pulses, a simulation based on the present cross sections, solving Bloch equations to compute the Ps populations, has been implemented. This highlights the challenges to be solved in this critical part of GBAR. References [1] The GBAR Collaboration 2011 CERN-SPSC-2011-029, SPSC-342 [2] P. Debu, Hyperfine Interact., 212, 51 (2012). [3] M. T. McAlinden et al., Phys. Rev. A 65, 032711 (2002). [4] S. Roy and C. Sinha, Eur. Phys. J. D 47, 327 (2008). [5] J. Mitroy, Phys. Rev. A 52, 2859 (1995). [6] J. Hanssen et al., Phys. Rev. A 63, 012705 (2001). [7] S. Chandrasekhar, Astrophys. J. 100, 176 (1944). [8] C. Le Sech, J. Phys. B: At. Mol. Opt. Phys. 30, L47 (1997). [9] J.P. Merrison et al., Phys. Rev. Lett. 78, 2728 (1997).

The GBAR experiment, recently approved at the CERN AD facility, is designed to perform a direct test of the weak equivalence principle on antimatter by measuring the acceleration of anti-hydrogen atoms in the gravitational field of the Earth. GBAR will complement other experiments with antimatter by synthesizing Hbar+, to facilitate its manipulation. Hbar+ will be obtained by two successive reactions with positronium (Ps). This requires a high-density Ps cloud as a target for antiprotons in the keV range. The Ps target will be produced by a pulse of over 10 billion positrons impinging on a converter. GBAR is developing two novel approaches for preparation of the ingredient beams. One is the electrostatic deceleration of the 100-keV antiproton beam from the CERN-ELENA facility, avoiding a degrader foil and accumulation trap. The other is the use of an electron linac to produce positron bunches, avoiding a radioactive source. The positron bunches are accumulated in a Penning-Malmberg trap using an energy-bunching technique and cooled by a pre-loaded electron cloud. Theoretical modeling of the Hbar+ reaction cross-section (see contribution by P. Comini et al.) predicts different possibilities that depend on incident antiproton energy and laser excitation of the Ps target. The antiproton decelerator will use a fast pulsing of a drift tube cavity and allow a tuneable antiproton energy to optimize the production of Hbar+. Details of these concepts and preliminary results will be presented.