Fragment flow and the multifragmentation phase space.
نویسندگان
چکیده
G. J. Kunde, '* W. C. Hsi, W. D. Kunze, ' A. Schiittauf, 3 A. Worner, ' M. Begemann-Blaich, ' Th. Blaich, D. R. Bowman, ' R. J. Charity, A. Cosmo, A. Ferrero, ~ C. K. Gelbke, 2 J. Hubele, ' G. Imme, s I. Iori, P. Kreutz, V. Lindenstruth, ' M. A. Lisa, W. G. Lynch, U. Lynen, ' M. Mang, T. Mohlenkamp, A. Moroni, W. F.J. Muller, ' M. Neumann, B. Ocker, C. A. Ogilvie, '~ G. F. Peaslee, J. Pochodzalla, ' G. Raciti, T. Rubehn, ' H. Sann, ' W. Seidel, V. Serfling, L. G. Sobotka, J. Stroth, ' L. Stuttge, 6 S. Tomasevic, W. Trautmann, ' M. B. Tsang, A. Tucholski to G. Verde, ~ C. W. Williams, E. Zude i and B. Zwieglinski' ' Gesellschaft fur Schwerionenforschung, 64220 Darmstadt, Germany 'Department of Physics and Astronomy and National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 3lnstitut fur Kernphysik, Universitat Frankfurt, 60486 Frankfurt, Germany Institut fur Kernchemie, Universitat Mainz, 55099 Mainz, Germany 'Department of Chemistry, Washington University, St Louis, .Missouri 63130 Centre de Recherches Nucleaires, 67037 Strasbourg, France Dipartimento di Fisica, Universita di Milano and INFN, 20133 Milano, Italy Dipartimento di Fisica dell' Universita and INFN, 95129 Catania, Italy 9Forschungszentrurn Rossendorf, 01314 Dresden, Germany 'OSoltan Institute for Nuclear Studies, 00-681 WarsawHoz, a 69, Poland (Received 9 August 1994; revised manuscript received 6 September 1994) Fragment distributions have been measured for Au + Au collisions at E/A = 100 and 1000 MeV. A high detection efficiency for fragments was obtained by combining the ALADIN spectrometer and the MSU-Miniball/WU-Miniwall array. At both energies the maximum multiplicity of intermediate mass fragments (IMF) normalized to the size of the decaying system is about one IMF per 30 nucleons but the element distributions show significant differences. Within a coalescence picture the suppression of heavy fragments in central collisions at E/A = 100 MeV may be related to a reduction of the density in momentum space which is caused by the collective expansion.
منابع مشابه
Sizes in Nuclear Multifragmentation and the Statistical Exploration of Fragmentation Phase Space
The multiplicity distributions for individual fragment Z values in nuclear multifragmentation are binomial. The extracted maximum value of the mul-tiplicity, m Z , is found to depend on Z according to m Z = Z 0 /Z, where Z 0 is the source size. This is shown to be a strong indication of statistical coverage of fragmentation phase space. The inferred source sizes coincide with those extracted fr...
متن کاملStatistical Exploration of Fragmentation Phase Space and Source Sizes in Nuclear Multifragmentation
The multiplicity distributions for individual fragment Z values in nuclear multifragmentation are binomial. The extracted maximum value of the multiplicity, mZ , is found to depend on Z according to mZ = Z0/Z, where Z0 is the source size. This is shown to be a strong indication of statistical coverage of fragmentation phase space. The inferred source sizes coincide with those extracted from the...
متن کاملFlow effects on multifragmentation in the canonical model
A prescription to incorporate the effects of nuclear flow on the process of multifragmentation of hot nuclei is proposed in an analytically solvable canonical model. Flow is simulated by the action of an effective negative external pressure. It favors sharpening the signatures of liquid-gas phase transition in finite nuclei with increased multiplicity and a lowered phase transition temperature....
متن کاملStatistical evolution of fragment isospin in nuclear multifragmentation
The knowledge of the isotope composition of fragments produced in nuclear multifragmentation can help in resolving important problems: Do the fragments keep the memory of the initial dynamical stage or are they produced statistically? How does the isospin influence the disintegration of finite nuclei and what is the difference to the case of nuclear matter? What is the isospin dependence of the...
متن کاملQuasi-gaussian fixed points and factorial cumulants in nuclear multifragmentation
We re-analyze the conditions for the phenomenon of intermittency (selfsimilar fluctuations) to occur in models of multifragmentation. Analyzing two different mechanisms, the bond-percolation and the ERW (Elattari, Richert and Wagner) statistical fragmentation models, we point out a common quasigaussian shape of the total multiplicity distribution in the critical range. The fixed-point property ...
متن کاملN ov 1 99 8 Isotope thermometry in nuclear multifragmentation
A systematic study of the effect of fragment−fragment interaction, quantum statistics, γ-feeding and collective flow is made in the extraction of the nuclear temperature from the double ratio of the isotopic yields in the statistical model of one-step (Prompt) multifragmentation. Temperature is also extracted from the isotope yield ratios generated in the sequential binary-decay model. Comparis...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Physical review letters
دوره 74 1 شماره
صفحات -
تاریخ انتشار 1995