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PROGRESS in RESEARCH April 1, 2002 – March 31, 2003 PROGRESS IN RESEARCH April 1, 2002 – March 31, 2003 Cyclotron Institute Texas A&M University College Station, Texas TABLE OF CONTENTS Introduction ............................................................................................................................................... ix R.E. Tribble, Director SECTION I: NUCLEAR STRUCTURE, FUNDAMENTAL INTERACTIONS AND ASTROPHYSICS Isoscalar giant dipole resonance for several nuclei with A ≥ 90.......................................................... I-1 Y. –W. Lui, X. Chen, H. L. Clark, B. John, Y. Tokimoto, D. H. Youngblood Giant resonances in 46, 48Ti ................................................................................................................... I-4 Y. Tokimoto, B. John*, X. Chen, H. L. Clark, Y. –W. Lui and D. H. Youngblood Determination of the direct capture contribution for 13N(p,γ)14O from the 14O →13N + p asymptotic normalization coefficient ..................................................................................................... I-6 X. Tang, A. Azhari, C. Fu, C. A. Gagliardi, A. M. Mukhamedzhanov, F. Pirlepesov, L. Trache, R. E. Tribble, V. Burjan, V. Kroha and F. Carstoiu Breakup of loosely bound nuclei at intermediate energies as indirect method in nuclear 8 astrophysics: B and the S17 astrophysical factor.................................................................................. I-8 F. Carstoiu, L. Trache, C. A. Gagliardi, and R. E. Tribble Elastic scattering of 8B on 12C and 14N ................................................................................................. I-10 A. Azhari, V. Burjan, F. Carstoiu, C. A. Gagliardi, X. Tang, L. Trache, and R. E. Tribble 8 Study of Li and the astrophysical S17(0) factor .................................................................................. I-11 L. Trache, A. Azhari, F. Carstoiu, H. L. Clark, C. A. Gagliardi, Y.-W. Lui, A. M. Mukhamedzhanov, X. D. Tang, N. Timofeyuk and R.E. Tribble 14 7 Remeasurement of N+ Be for the astrophysical S17(0) factor.......................................................... I-12 G. Tabacaru, A. Azhari, J. Brinkley, V. Burjan, C. Fu, C. A. Gagliardi, X. Tang, L. Trache, R. E. Tribble The physics of STAR at RHIC.............................................................................................................. I-13 C. A. Gagliardi, T. W. Henry, R. E. Tribble, M. A. Vasiliev, and the STAR Collaboration TWIST: Measuring the space-time structure of muon decay........................................................... I-15 C. A. Gagliardi, J. R. Musser, R. E. Tribble, M. A. Vasiliev, and the TWIST Collaboration i Absolute Drell-Yan dimuon cross sections in 800 GeV/c pp and pd collisions.................................. I-17 C. A. Gagliardi, E. A. Hawker, R. E. Tribble, M. A. Vasiliev, and the FNAL E866/NuSea Collaboration High precision measurement of the superallowed 0+ → 0+ beta decay of 22Mg ................................ I-19 J. C. Hardy, V. E. Iacob, M. Sanchez-Vega, R. G. Neilson, A. Azhari, C. A. Gagliardi, V. E. Mayes, X. Tang, L. Trache and R. E. Tribble The use of Monte Carlo calculations in the determination of a Ge detector efficiency curve between 50 and 1400 keV............................................................................................................ I-22 J. C. Hardy, V. E. Iacob, M. Sanchez-Vega, R. G. Neilson, J. Nelson and R. G. Helmer TRIUMF E-823: High precision branching ratio measurement for the superallowed β decay of 74Rb: a prerequisite for exacting tests of the standard model........................................................ I-26 J. C. Hardy and V. I. Iacob Precise efficiency calibration of an HPGe detector up to 3.5 MeV, with measurements and Monte Carlo calculations ...................................................................................................................... I-28 N. Nica, J. C. Hardy, V. E. Iacob and R. G. Helmer Beta decay of 62Ga.................................................................................................................................. I-31 B. C. Hyman, V. E. Iacob, A. Azhari, C. A. Gagliardi, J. C. Hardy, V. E. Mayes, R. G. Neilson, M. Sanchez-Vega, X. Tang, L. Trache and R. E. Tribble T=5/2 states in 9Li: Isobaric analog states of 9He ................................................................................ I-34 G. Chubarian, V. Z. Goldberg, G. V. Rogachev, J. J. Kolata, D. Aleksandrov, A. Fomichev, M. S. Golovkov, Yu. Ts. Oganessian, A. Rodin, B. Skorodumov, R. S. Slepnev, G. Ter-Akopian and W. H. Trzaska and R. Wolski α -Structure in 22Ne by the resonance 18O+4He scattering ................................................................. I-35 G. Chubarian, V. Z. Goldberg, G. V. Rogachev, M. V. Rozhkov B. B. Skorodumov, W. H. Trzaska, K.-M. Kallman, T. Lönnroth and M. Mutterer Recent results in the studies of nuclear structure by resonance scattering with radioactive beams.......................................................................................................................... I-36 G. Chubarian, V. Z. Goldberg, W. H. Trzaska, G. V. Rogachev, J. J. Kolata, A. Andreyev, C. Angulo, M. J. G. Borge, S. Cherubini, G. Crowley, A. Fomichev, M. Gorska, M. Gulino, M. S. Golovkov, M. Huyse, K. -M. Källman, M. Lattuada, T. Lönnroth, M. Mutterer, R. Raabe, A. Rodin, S. Romano, M. V. Rozhkov, B. B. Skorodumov, C. Spitaleri, O. Tengblad, G. Ter-Akopian, A. Tumino, P. Van Duppen, R. Wolski ii Evolution of shell structure to drip lines near 1P shell....................................................................... I-37 V. Z. Goldberg Final state interaction or a 3H excited state?....................................................................................... I-39 V. Z. Goldberg, G. V. Rogachev, J. J. Kolata, L. V. Grigorenko, F. D. Becchetti, P. A. DeYoung, J. D. Hinnefeld, L. O. Lamm, J. Lupton, T. W. O’Donnell, D. A. Roberts and S. Shaheen SECTION II: HEAVY ION REACTIONS Temperature dependence of the isospin distillation in nuclear fragmentation.................................II-1 D. V. Shetty for the NIMROD Collaboration Midrapidity emission in nuclear fragmentation ..................................................................................II-2 D. V. Shetty for the NIMROD Collaboration Isospin dependence of the <N/Z> in nuclear fragmentation...............................................................II-3 D. V. Shetty, for the NIMROD Collaboration Isospin dependence of the charge distribution in nuclear fragmentation..........................................II-4 D. V. Shetty, S. J. Yennello, E. Martin, A. Keksis, and G. Souliotis Isotopic scaling of heavy projectile residues from deep-inelastic collisions at fermi energies ..........................................................................................................................................II-5 G. A. Souliotis, D. V. Shetty, M. Veselsky, G. Chubarian, L. Trache, A. Keksis, E. Martin and S. J. Yennello Enhanced production of neutron-rich rare isotopes in peripheral collisions at fermi energies ..........................................................................................................................................II-7 G. A. Souliotis, M. Veselsky, G. Chubarian, L. Trache, A. Keksis, E. Martin, D. V. Shetty and S. J. Yennello Energy dependence of the isotopic composition in nuclear fragmentation .......................................II-9 D. V. Shetty, S. J. Yennello, E. Martin, A. Keksis, and G. Souliotis Progress in research of isospin equilibration .....................................................................................II-10 E. Martin for the NIMROD Collaboration Isospin dependence of quasiprojectile fragmentation using mass 40 isobars on 112, 124Sn using FAUST...........................................................................................................................II-11 A. L. Keksis, M. Veselsky, G. A. Souliotis, E. Martin, D. Shetty and S. J. Yennello iii Evidence of critical behavior in the disassembly of nuclei with A ~ 36............................................II-12 Y. G. Ma, R. Wada, K. Hagel, J. Wang, T. Keutgen, Z. Majka, M. Murray, L. Qin, P. Smith, J. B. Natowitz, R. Alfarro, J. Cibor, M. Cinausero, Y. El Masri, D. Fabris, E. Fioretto, A. Keksis, M. Lunardon, A. Makeev, E. Martin, Martinez-Davalos, A. Menchaca-Rocha, G. Nebbia, G. Prete, V. Rizzi, A. Ruangma, D. V. Shetty, G. Souliotis, P. Staszel, M. Veselsky, G. Viesti, E. M. Winchester and S. J. Yennello Multifragmentation and cold fragment emission...............................................................................II-14 R. Wada, T. Keutgen, K. Hagel, M. Murray, Y. G. Ma, L. Qin, J. S. Wang, P. Smith, J. B. Natowitz, A. Makeev, A. Ono and the NIMROD Collaboration Neutron ball efficiency calculation for NIMROD..............................................................................II-15 M. Murray, R. Wada, T. Keutgen, K. Hagel, Y. G. Ma, J. B. Natowitz, J. Cibor, L. Qin, C. Hamilton, A. Makeev, A. Ono and the NIMROD Collaboration Reaction dynamics and equation of state in fermi energy heavy ion reactions...............................II-16 R. Wada, T. Keutgen, K. Hagel, M. Murray, Y. G. Ma, L. Qin, J. S. Wang, P. Smith, J. B. Natowitz, A. Makeev, A. Ono and the NIMROD Collaboration Nuclear expansion and cooling in heavy ion reactions at intermediate energy...............................II-17 J. S. Wang, R. Wada, K. Hagel, Y. Ma, T. Keutgen, L. Qin, M. Murray, A. Makeev, P. Smith, J. B. Natowitz,
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