Bulletin of the American Physical Society
2009 APS April Meeting
Volume 54, Number 4
Saturday–Tuesday, May 2–5, 2009; Denver, Colorado
Session W10: Nuclear Reactions: Heavy Ions/Rare Isotope Beams I |
Hide Abstracts |
Sponsoring Units: DNP Chair: Misak Sargsian, Florida International University Room: Governor's Square 10 |
Tuesday, May 5, 2009 10:45AM - 10:57AM |
W10.00001: Study of bound and unbound states in the halo nucleus $^{11}$Be using the $^{10}$Be(d,p) reaction in inverse kinematics K.T. Schmitt Light neutron-rich nuclei have been used widely as test cases for ab initio theory, especially to test its ability to predict phenomena that do not occur in stable nuclei, such as halo structure. Extensive experimental data demonstrates that level inversion of the lowest states leads to halo properties in the ground state of $^{11}$Be. Less is known, however, about the excited states of this nucleus. Specifically, the spectroscopic factor of the only bound excited state is disputed and spin-parity assignments for the unbound states are unconfirmed or tentative. A neutron transfer experiment at the HRIBF should improve our understanding of these states. The setup of this experiment will be described, including advancements in fast-timing MCP based detectors for low-Z beams, detection of recoils at small lab angles, and detector arrangement for the ORRUBA array. [Preview Abstract] |
Tuesday, May 5, 2009 10:57AM - 11:09AM |
W10.00002: Charged Particle Characteristics of the $^{124}$Xe+$^{112,124}$Sn reactions at 50A MeV A.B. McIntosh, S. Hudan, Z. Gosser, C.J. Metelko, M. Rudolph, R. Yanez, R.T. de Souza, A. Chbihi, M. Famiano, M.O. Fr\'egeau, J. Gauthier, J. Moisan, R. Roy, C. Schwarz, S. Bianchin, W. Trautmann To investigate the density dependence of the symmetry energy in the nuclear equation of state, neutrons and charged particles produced in the reactions $^{124}$Xe+$^{112,124}$Sn at E/A=50MeV were measured. Charged particles emitted in the angular range 2.8-14.5\r{ } were detected with the Indiana array FIRST with good energy and angular resolution. Charged products at larger angles (30-45\r{ }) were detected in the Si strip array LASSA. The DEMON array was used to identify neutrons and measure their kinetic energies using pulse-shape discrimination and TOF. Isotopic resolution was obtained in all charged particle detectors. Energy distributions, angular distributions, and the Z distributions of charged products will be presented. Yields of isotopically resolved fragments will be compared; the effect of the target N/Z on the production of these fragments will be examined. [Preview Abstract] |
Tuesday, May 5, 2009 11:09AM - 11:21AM |
W10.00003: Production of projectile-like-fragments with light systems in mass asymmetric, intermediate energy reactions Michael Quinlan, Iwona Pawelczak, Jan T\~oke, Udo Schr\"oder The reactions $^{40,48}$Ca + $^{112,124}$Sn at a bombarding energy of 45 MeV/A were studied with the 4$\pi $ charged particle detector array, CHIMERA, at the Laboratori Nazionali del Sud in Catania, Italy. Measured observables were the charged particle multiplicities, their individual energy, charge, and in some cases, isotopic identity. Of particular interest is the production of intermediate mass fragments and their correlations with projectile-like fragments (PLFs) formed in the reaction. Data concerning the production of PLFs will be presented; specifically their charge, energy, and angular distributions. The reaction mechanism and isotopic effects with be discussed. [Preview Abstract] |
Tuesday, May 5, 2009 11:21AM - 11:33AM |
W10.00004: Mid-peripheral collisions around the Fermi energy: comparison with an event generator Sylvie Hudan, A.B. McIntosh, Z. Gosser, C. Metelko, M. Rudolph, R. Yanez, R. de Souza, A. Chbihi, M. Famiano, M.O. Fregeau, J. Gauthier, J. Moisan, R. Roy, S. Bianchin, C. Schwarz, W. Trautmann, D. Durand The reactions $^{124}$Xe+$^{112,124}$Sn at E/A=50MeV have been recently measured. For mid-peripheral collisions, the projectile-like-fragment has been measured in coincidence with emitted particles (charged particles and neutrons). Experimental data will be compared to those obtained by the event generator Elie[1]. This two-step event generator consists of an entrance channel phase using a random process to determine the initial partition; and of kinematic propagation and secondary decay as the second phase. Experimental and generated energy distributions, angular distributions, and Z distributions of charged products will be examined. Yields of isotopically resolved fragments will be studied, including the effect of the target N/Z. [1] Elie: an event generator for nuclear reactions, Dominique Durand, arXiv:0803.2159 [Preview Abstract] |
Tuesday, May 5, 2009 11:33AM - 11:45AM |
W10.00005: Measuring Near and Sub-Barrier Fusion of neutron-rich oxygen nuclei on a carbon target R.T. deSouza, Z. Gosser, M.J. Rudolph, B. Floyd, S. Hudan, A.B. McIntosh, H. Dussan, C.J. Horowitz, M. Famiano, A. Chbihi, J.-P. Wieleczko, C. Gross, F. Liang, D. Shapira, R. Varner, I. Pawelczak, M. Quinlan, Y.T. Tsai, W.U. Schroeder, J. Toke Experimental investigation of the sub-barrier fusion of neutron-rich light nuclei is important in understanding the crusts of neutron stars, the structure of neutron-rich nuclei, and fusion dynamics of neutron-rich nuclei. It has recently been proposed that X-ray superbursts may originate from carbon burning ignited by heat from the fusion of neutron-rich oxygen nuclei in the crusts of accreting neutron stars [1]. An enhancement in the fusion probability, pronounced at energies near and below the Coulomb barrier, may signal the presence of different fusion dynamics as compared to the fusion of less neutron-rich nuclei. To assess if the fusion probability is enhanced for neutron-rich nuclei, we intend to measure the fusion excitation function of $^{16,20}$O + $^{12}$C for E$_{lab}<$ 60 MeV. We will describe the experimental setup associated with such a measurement. [1] C.J. Horowitz, H. Dussan, and D.K. Berry, \textbf{Phys. Rev. C 77, 045807~(2008)} [Preview Abstract] |
Tuesday, May 5, 2009 11:45AM - 11:57AM |
W10.00006: Nuclear Radii Calculations in Various Theoretical Approaches Ivan Novikov, Carlos Merino, Yuli Shabelski The information about sizes and nuclear density distributions in unstable (radioactive) nuclei is usually extracted from the data on interaction of radioactive nuclear beams with a nuclear target. We show that in the case of nucleus-nucleus collisions the extracted parameters depend rather strongly on the used theoretical approach. The values of root-mean-square (r.m.s.) radii for nuclei with atomic weights 12-40 vary by approximately 0.1 fm when the analysis is provided in the optical approximation, in rigid target approximation and in the exact expression of Glauber Theory. We present several examples of r.m.s. radii calculations using these three theoretical approaches. [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700