4-5 August 2012
The Sebel Hotel
Australia/Sydney timezone
Final program now available! See you in Cairns!
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Contribution List

Displaying 19 contributions out of 19
Session: Simulations
The problem of astrophysical site(s) for the r-process is still shrouded in mystery despite more than a half century of studies. Although neutrino driven winds have been considered to be the most likely success, recent state of the art hydrodynamic simulations show that it is seriously difficult to achieve suitable conditions for $r$-process by that scenario. We are reinvestigating the other astro ... More
Presented by Dr. Nobuya NISHIMURA on 4 Aug 2012 at 2:00 PM
The applications of stellar elemental abundances are numerous. The different groups of elements work as tracers of various formation processes, e.g. alpha-elements and odd-Z elements are created both in hydrostatic burning and supernova explosions. An abundances of every single element can trace differing features/parameters of the supernova such as mass and explosion energy. By comparing heavy ... More
Presented by Dr. Camilla Juul HANSEN on 4 Aug 2012 at 11:15 AM
Session: Simulations
In this contribution, we give overview about a current status of multidimensional radiation hydrodynamic simulations of core-collapse supernovae. In addition to 3D hydrodynamics and general relativity, both of which are now considered as the most important ingredients for making successful explosions, we discuss also impacts of nuclear equations of state on the supernova dynamics. We repo ... More
Presented by Dr. Kei KOTAKE on 4 Aug 2012 at 1:30 PM
Session: Experiments
Beta-decay spectroscopy of the nuclei far from the stability is one of sensitive methods to shed light on evolution of nuclear structure toward extreme neutron-to-proton ratios. The beta-decay related information is also essential to study the rapid neutron-capture process (r-process), which is responsible for producing about half of the elements heavier than Fe in the universe. A signi cant pro ... More
Presented by Shunji NISHIMURA on 5 Aug 2012 at 1:00 PM
Ground state masses belong to the most essential nuclear quantities for our understanding of nucleosynthesis processes in stars. Particularly for the r-process, masses of very neutron-rich nuclei are needed. The need is best explained by the fact that mass differences of specific neighboring nuclei define the neutron separation energy and thus determine the pathway of the process on the chart of n ... More
Presented by Dr. Yuri LITVINOV on 5 Aug 2012 at 10:00 AM
Session: Experiments
Despite more than half a century of intensive research, the nucleosynthesis of heavy nuclei remains is still an open questions in nuclear astrophysics. Besides the unknown scenario where the rapid neutron-capture process occurs, new incognita about the very synthesis mechanism are presently under study. The Puzzle will only be solved when the properties of the neutron-rich nuclei involved are well ... More
Presented by Jorge PEREIRA on 5 Aug 2012 at 11:30 AM
The $\beta$-decays of r-process neutron rich nuclei near the doubly magic $^{78}$Ni were studied at the Holifield Radioactive Ion Beam Facility (HRIBF) using an electromagnetic isobar separator. The half-lives of $^{82}$Zn (228$\pm$10 ms), $^{83}$Zn (117$\pm$20 ms) and $^{85}$Ga (93$\pm$7 ms) were determined for the first time. These half-lives were found to be dramatically different than th ... More
Presented by Dr. Miguel MADURGA on 5 Aug 2012 at 10:30 AM
We give a short review on necessary conditions in order to achieve a sufficient neutron/seed ratio for an r-process to occur, what are the candidate astrophysical sites to fulfill such conditions (supernovae, magnetar-forming supernovae, quark (super-)novae, neutron star mergers,...), what is their role in the chemical evolution of galaxies, and whether there existed a chance to produce superheavy ... More
Presented by Prof. Friedrich THIELEMANN on 4 Aug 2012 at 9:00 AM
A reoccurring theme throughout nuclear astrophysics is the need for and use of the best available nuclear data as input for astrophysics calculations. Relevant nuclear data includes, but is not limited to nuclear masses, partition functions, thermonuclear reaction rates, weak interaction rates and fission fragment distributions. With the r-process reaction flow typically far from direct experime ... More
Presented by Dr. Richard CYBURT on 4 Aug 2012 at 11:45 AM
We extend our analysis of archival 2000A HST STIS E230H echelle spectra of five metal-poor stars with modest r-process enhancements to rare light trans-ironic elements represented by very few lines. We illustrate potential pitfalls affecting abundance determinations of isolated weak lines in the blended ultraviolet, which we minimize by analyzing all five stars simultaneously and consistently, cal ... More
Presented by Ms. Ruth PETERSON on 4 Aug 2012 at 10:15 AM
I will discuss the origin of lighter heavy elements (Sr, Y, Zr) in neutrino-driven winds.
Presented by Almudena ARCONES on 4 Aug 2012 at 3:30 PM
We present new abundance determinations of the heavy elements germanium (Ge, Z=32), arsenic (As, Z=33), selenium (Se, Z=34), and tellurium (Te, Z=52) in several metal-poor stars enriched with r-process material. These recent results mark the first detection of As, Se, and Te in an r-process environment beyond the solar system. In addition, detection of the elements at the third r-process peak in ... More
Presented by Dr. Ian ROEDERER on 4 Aug 2012 at 10:45 AM
Session: Simulations
The classical (n,gamma)-(gamma,n) phase of r-process nucleosynthesis is well understood. Less well understood is the complex freezeout phase during which the last of the free neutrons are consumed. I present some calculations using simplified nuclear physics to help characterize the r-process freezeout.
Presented by Prof. Bradley MEYER on 4 Aug 2012 at 2:30 PM
The rapid neutron capture process (r-process) is thought to be responsible for the creation of more than half of all elements beyond iron. The scientific challenges to understanding the origin of the heavy elements beyond iron lie in both the uncertainties associated with astrophysical conditions that are needed to allow an r-process to occur and a vast lack of knowledge about the properties of nu ... More
Presented by Prof. Ani APRAHAMIAN on 4 Aug 2012 at 9:30 AM
Single-particle resonant states embedded in the continuum for $^{131,133}$Sn, in the vicinity of the neutron capture threshold for $^{130,132}$Sn(n,$\gamma$), are calculated by the analytical continuation of the coupling constant (ACCC) approach within the relativistic mean field (RMF) theory framework. Our fully self-consistent RMF calculations using the NL3 effective interaction, predict single ... More
Presented by Dr. Shi-Sheng ZHANG on 4 Aug 2012 at 4:30 PM
Session: Experiments
R. Surman and colleagues have shown how r-process nucleosynthesis abundances are affected by uncertainties in neutron capture cross sections in relatively long-lived nuclei near the r-process path, such as 130Sn. We have recently measured the (d,p) reactions with rare isotope beams of 126,128,130,132Sn and 134Te to study the single-neutron structure in these neutron-rich nuclei and inform the di ... More
Presented by Jolie CIZEWSKI on 5 Aug 2012 at 12:30 PM
The potential of an astrophysical environment for making r-process elements has been typically characterized by the neutron-to-seed ratio. We consider the rare earth peak as a new and independent tool for understanding the astrophysical conditions favorable for the main r-process. In the context of a high entropy r-process we discuss rare earth peak formation. We use features of a successful rare ... More
Presented by Dr. Matthew MUMPOWER on 4 Aug 2012 at 4:00 PM
β decays of the isotones with N = 126 are studied by shell-model calculations taking into account both the Gamow-Teller (GT) and first-forbidden (FF) transitions [1]. Shell-model interaction of Ref. [2] is adopted and a quenching of g_A^{eff}/g_A =0.7 is used for both the GT and FF transitions except for 0^{-} case. The FF transitions [3] are found to be important to reduce the beta-decay half-li ... More
Presented by Prof. Toshio SUZUKI on 4 Aug 2012 at 5:00 PM
Session: Experiments
β delayed neutron emission measurements around the third r-process peak
Presented by Mr. Roger CABALLERO-FOLCH on 5 Aug 2012 at 12:00 PM