EXA online conference 2021



Eberhard Widmann (Stefan Meyer Institute) , Johann Marton (Österreichische Akademie der Wissenschaften(ÖAW)) , Johann Zmeskal (SMI)

Welcome to the EXA 2021 online conference. The EXA 2021 will be an online only meeting. It is organized by the Stefan-Meyer-Institute for Subatomic Physics of the Austrian Academy of Sciences.

The scientific program comprises the following topics:

  • Antihydrogen: CPT and gravity
  • Leptonic atoms: QED and gravity
  • Kaon-nucleon and kaon-nucleus interaction
  • Low-energy QCD
  • Precision experiments with cold neutrons
  • Hadron physics with antiprotons
  • Hadron physics at LHC
  • Future facilities and instrumentation
Registration Form
  • Alberto Calivà
  • Alessio Porcelli
  • Alexey Petrov
  • Alina Weiser
  • Amit Nanda
  • Andreas Lanz
  • Andrei Ivanov
  • Anindita Karmakar
  • Anthony Thomas
  • Antonio Gioiosa
  • Art Olin
  • Avraham Gal
  • Ben Ohayon
  • Carsten Welsch
  • Catalina Oana Curceanu
  • Chhaya Sudhakar
  • Christian Regenfus
  • Claude Amsler
  • Claudio Lenz Cesar
  • Dan Murtagh
  • Daneshwar Bhandari
  • David Cassidy
  • Detlev Gotta
  • Eberhard Widmann
  • Eli Friedman
  • Elisa Meninno
  • Elise Wursten
  • Elvyn Ojeda
  • Eric Hunter
  • Eric Hunter
  • Eryk Czerwiński
  • Eulogio Oset Baguena
  • Florin Catalin Sirghi
  • Fumihiro Yoshizu
  • Fuminori Sakuma
  • Georgios Mantzaridis
  • giulia gosta
  • Grigory Korenman
  • Hans Stroeher
  • Hartmut Hillemanns
  • Hendrik Schürg
  • Herbert Orth
  • Hiroki Tada
  • Hiroyuki A. Torii
  • Ivo Schulthess
  • Jacob Thorne
  • Jaroslava Obertova
  • Jiri Mares
  • Johann Haidenbauer
  • Johann Marton
  • Johann Zmeskal
  • Josef Pochodzalla
  • Kajal Dixit
  • Karin Schönning
  • Kazimierz Bodek
  • Keerthana Rajan L
  • Klaus Blaum
  • Klaus Jungmann
  • Koichiro Shimomura
  • Kristian Piscicchia
  • Krzysztof Pachucki
  • Laura Fabbietti
  • Lilian Nowak
  • Lisa Glöggler
  • Magdalena Skurzok
  • Manuel Zeyen
  • Marcus Bumbar
  • Markus Wiesinger
  • Marlene Tuechler
  • Martin Simon
  • Masaki Hori
  • Massimo Passera
  • Miguel Marques
  • Milena Vujanovic
  • Munera Alrashed
  • Nina Shevchenko
  • Nora Brambilla
  • Olivier Rousselle
  • Ophir Ruimi
  • Oton Vazquez Doce
  • Paolo Crivelli
  • Paolo Girotti
  • Paolo Giubellino
  • Patrick Riegler
  • Paul Buehler
  • Pauline Comini
  • Pawel Moskal
  • Pin-Jung Chiu
  • Piotr Froelich
  • Pranav Kulkarni
  • Raffaele Del Grande
  • Randolf Pohl
  • Reinhard Alkofer
  • Renat Sultanov
  • Roman Lavička
  • Salsabeel Ahmed Abdelaal Ahmed
  • Seiso Fukumura
  • Shinji Okada
  • Shoichiro Nishimura
  • Siddharth Rajamohanan
  • Skyler Degenkolb
  • Stanley Brodsky
  • Stefano Migliorati
  • Stephan Schiller
  • Svetlana Chesnevskaya
  • Tadashi Hashimoto
  • Takashi Higuchi
  • Tetsuo Hyodo
  • Theun van veen
  • Thomas Chen
  • Tim Sailer
  • Tim Wolz
  • Tomona Kinugawa
  • Toya Tanaka
  • vasanthi loganathan
  • Volodymyr Rodin
  • Wai Lai
  • Waleed Khalid
  • Wioleta Rzęsa
  • Xing Fan
  • Yoshitaka KUNO
  • Yuji Ishikawa
    • 10:00 10:30
      Muon g-2 - Status of theory and experiment 30m
      Speakers: Dr Massimo Passera (INFN, Padua) , Mr Paolo Girotti (INFN Pisa and University of Pisa)
    • 10:30 10:50
      Measurement of the permanent electric dipole moment of the neutron 20m

      A nonzero permanent electric dipole moment (EDM) of a particle implies the violation of time-reversal symmetry. Considering $CPT$ conservation, this also indicates the violation of the combined symmetry of charge conjugation and parity ($CP$), which is one of the three essential criteria to explain the baryon asymmetry of the Universe.

      At the Paul Scherrer Institute, we measured the neutron EDM by applying Ramsey's method of separated oscillatory fields with stored ultracold neutrons (UCN) in vacuum at room temperature. In this experiment, a $^{199}$Hg comagnetometer and an array of vapor $^{133}$Cs magnetometers [1] were deployed to monitor, control, and correct for magnetic-field changes. In addition, dedicated measurements [2] were carried out to assess the systematic effects related to magnetic-field nonuniformity. Unprecedented understanding and assessment of systematic effects have been achieved. The statistical analysis was performed on blinded data [3] by two independent groups to avoid any bias on the data-selection criteria. The final value taken from the midpoint of the results from the two analysis groups, adding various systematic effects that have been estimated independently, gives $d_{\rm n} = \left(0.0 \pm 1.1_{\rm stat} \pm 0.2_{\rm sys} \right)\times 10^{-26}\, e\cdot{\rm cm}$. This may be interpreted as an upper limit of $\left| d_{\rm n} \right| < 1.8 \times 10^{-26}\, e\cdot{\rm cm}$ (90% C.L.), which sets the current best limit on the EDM of the neutron [4].

      [1] C. Abel et al. Phys. Rev. A 101, 053419 (2020).
      [2] C. Abel et al. arXiv:2103.09039 [physics.ins-det] (2021).
      [3] N. J. Ayres et al. Eur. Phys. J. A 57:152 (2021).
      [4] C. Abel et al. Phys. Rev. Lett. 124, 081803 (2020).

      Speaker: Pin-Jung Chiu (Paul Scherrer Institute)
    • 10:50 11:20
      Alpha - Laser cooling of antihydrogen atoms 30m
      Speaker: Prof. Claudio Cesar (University of Rio de Janeiro)
    • 11:20 11:40
      Recent results from the BASE experiment 20m
      Speaker: Dr Elise Wursten (RIKEN)
    • 11:40 12:00
      Laser spectroscopy of pionic helium atoms 20m
      Speaker: Dr Masaki Hori (Max-Planck Institute for Quantum Optics)
    • 10:00 10:30
      New developments in low-energy QCD 30m
      Speaker: Prof. Anthony Thomas (University of Adelaide)
    • 10:30 10:50
      Pionic hydrogen and deuterium 20m

      The strong-interaction effects both in pionic hydrogen and deuterium have been re-determined with improved precision. The hadronic shift and width in pionic hydrogen together with the hadronic shift in pionic deuterium constitute a one-fold constraint for the two independent pion-nucleon scattering lengths. Furthermore, the hadronic width in pionic deuterium measures the transition strength of s-wave pions on an isoscalar nucleon-nucleon pair which is an independent quantity not related to the pion-nucleon scattering lengths. The experiment was performed at the high-intensity low-energy pion beam of the Paul Scherrer Institute by using the cyclotron trap and a high resolution Bragg spectrometer with spherically bent crystals. The pion-nucleon scattering lengths and other physical quantities extracted from the atom data are in good agreement with the results obtained from pion-nucleon and nucleon-nucleon scattering experiments and confirm that a consistent picture is achieved for the low-energy pion-nucleon sector with respect to the expectations of chiral perturbation theory.

      Speaker: Prof. Detlev Gotta (Forschungszentrum Jülich)
    • 10:50 11:20
      Overview - Hypernuclei and Hyperatoms 30m
      Speaker: Prof. Josef Pochodzalla (GSI, Darmstadt)
    • 11:20 11:40
      The neutron as a building block 20m
      Speaker: Prof. Miguel Marques (Universite de Caen, LPCC)
    • 11:40 12:10
      Measurements of hadron-hadron interactions with ALICE 30m
      Speaker: Prof. Laura Fabbietti (TUM)
    • 10:00 12:00
      Thursday: Discussion of contributed papers in break-out rooms
    • 10:10 10:40
      Low-energy kaon-nuclei interactions studies at DAFNE 30m

      The strong interaction theory in the low energy regime, is still missing fundamental experimental results in order to achieve a breakthrough in its understanding. Among these, the investigation of the low-energy kaon nucleon/nuclei processes and of the Kaonic atoms play a key-role. The talk will give an outline of the results obtained by the AMADEUS and SIDDHARTA experiments performed at the DAFNE Collider of LNF-INFN.

      In the first part of the presentation the K- single and multi-nuclear absorptions on various light nuclear targets both at-rest and in-flight (for a kaon momenta up to 120 MeV/c) will be discussed with a focus on the nature of the Λ(1405), the non-resonant hyperon pion formation amplitude below the K-N threshold and the yields and cross sections of K- single and multi-nucleon interactions.

      The second part of the talk will be concerned on high sensitivity X-ray spectroscopic measurements of low-lying orbits transitions in kaonic atoms, which are presently being performed by the SIDDHARTA-2 experiment, with the main aim to perform the first ever measurement of kaonic deuterium.

      I shall conclude with future plans on kaonic-nuclei interaction studies at DAFNE, beyond SIDDHARTA-2 measurement.

      Speaker: Dr Kristian Piscicchia (Centro FERMI, Rome)
    • 10:40 11:00
      Minimizing Plasma Temperature for Antimatter Mixing Experiments 20m
      Speaker: Dr Eric Hunter (Stefan Meyer Institute, SMI)
    • 11:00 11:20
      Current understanding of the Kbar-N, Kbar-atom and Kbar-nucleus interactions 20m
      Speaker: Prof. Eulogio Oset (University of Valencia)
    • 11:20 11:40
      Summary of the K-pp bound-state observation in E15 20m
      Speaker: Dr Fuminori Sakuma (RIKEN)
    • 11:40 12:00
      Kaonic atom X-rays at J-PARC 20m
      Speaker: Dr Tadashi Hashimoto (JAEA)
    • 12:00 12:15
      Farewell 15m