Neutrons from projectile fragmentation at 600 MeV/nucleon
Journal article, 2023
The neutron emission in projectile fragmentation at relativistic energies was studied with the Large-Area-Neutron-Detector LAND coupled to the ALADIN forward spectrometer at the GSI Schwerionen-Synchrotron (SIS). Stable Sn124 and radioactive Sn107 and La124 beams with an incident energy of 600 MeV/nucleon were used to explore the N/Z dependence of the identified neutron source. A cluster-recognition algorithm is applied for identifying individual particles within the hit distributions registered with LAND. The obtained momentum distributions are extrapolated over the full phase space occupied by the neutrons from the projectile-spectator source. The mean multiplicities of spectator neutrons reach values of up to about 11 and depend strongly on the isotopic composition of the projectile. An effective source temperature of T≈2-5 MeV, monotonically increasing with decreasing impact parameter, is deduced from the transverse momentum distributions. For the interpretation of the data, calculations with the statistical multifragmentation model were performed. The variety of excited projectile spectators assumed to decay statistically is represented by an ensemble of excited sources with parameters determined previously from the fragment production observed in the same experiments. The obtained agreement is very satisfactory for more peripheral collisions where, according to the model, neutrons are mainly emitted during the secondary decays of excited fragments. The neutron multiplicity in more central collisions is underestimated, indicating that other sources besides the modeled statistical breakup contribute to the observed neutron yield. The choice made for the symmetry-term coefficient of the liquid-drop description of produced fragments has a weak effect on the predicted neutron multiplicities.
Author
P. Pawłowski
Polish Academy of Sciences
J. Brzychczyk
Jagiellonian University in Kraków
N. Buyukcizmeci
Selçuk University
Håkan T Johansson
Chalmers, Physics, Subatomic, High Energy and Plasma Physics
W. Trautmann
Helmholtz
A. Wieloch
Jagiellonian University in Kraków
P. Adrich
Narodowe Centrum Badan Jadrowych
T. Aumann
Helmholtz
T. Barczyk
Jagiellonian University in Kraków
S. Bianchin
Helmholtz
K. Boretzky
Helmholtz
Alexander Botvina
Goethe University Frankfurt
Helmholtz Research Academy Hesse for FAIR
A. Chbihi
Grand Accélérateur National d'Ions Lourds (GANIL)
J. Cibor
Polish Academy of Sciences
B. Czech
Polish Academy of Sciences
H. Emling
Helmholtz
J. D. Frankland
Grand Accélérateur National d'Ions Lourds (GANIL)
M. Heil
Helmholtz
A. Le Fèvre
Helmholtz
Y. Leifels
Helmholtz
J. Lühning
Helmholtz
J. Łukasik
Polish Academy of Sciences
Helmholtz
U. Lynen
Helmholtz
Z. Majka
Jagiellonian University in Kraków
I. N. Mishustin
Frankfurt Institute for Advanced Studies
W. F.J. Müller
Helmholtz
R. Ogul
Selçuk University
H. Orth
Helmholtz
R. Palit
Helmholtz
D. Rossi
Helmholtz
C. Schwarz
Helmholtz
C. Sfienti
Johannes Gutenberg University Mainz
H. Simon
Helmholtz
K. Summerer
Helmholtz
H. Weick
Helmholtz
B. Zwiegliński
Narodowe Centrum Badan Jadrowych
Physical Review C
24699985 (ISSN) 24699993 (eISSN)
Vol. 108 4 044610Atomic nuclei that merely exist
Swedish Research Council (VR) (2022-04248), 2023-01-01 -- 2026-12-31.
Subject Categories
Subatomic Physics
DOI
10.1103/PhysRevC.108.044610