Speaker
Description
An experiment measuring the Coulomb-excitation cross section, σC [1] in neutron-rich tin nuclei
( 124 Sn– 134 Sn) at relativistic energies was performed at GSI, Darmstadt with the aim to constrain
the slope of the symmetry energy, L. This particular cross section correlates with dipole polariz-
ability, α D , a well-established observable for constraining L [2], which enables achieving the same
goal but in a simpler and more accurate manner with the used experimental setup [3].
Large acceptance spectrometer R3B-GLAD was used to conduct the experiment as a part of the
FAIR Phase-0 campaign [4]. Neutron-rich tin isotopes were produced in fragmentation and fission
reactions at energies close to 1 GeV/u, while a lead target was used to provide a strong field to
induce Coulomb excitations. At these energies, de-excitation occurs through the emission of gam-
mas and neutrons which were detected using the CALIFA gamma calorimeter [5] and NeuLAND
neutron detector [6].
In the scope of this contribution, ongoing analysis with some preliminary results will be presented.
[1] T.Aumann, C.A.Bertulani, Prog. Part. Nucl. Phys. 112 (2020) 103753
[2] S.Bassauer et al., Phys. Lett. B 810 (2020) 135804
[3] A.Horvat, Doctoral thesis, Technische Universität Darmstadt (2019)
[4] R3B Collaboration, https://www.r3b-nustar.de/.
[5] H. Alvarez Pol et al., Nucl. Instrum. Meths. Phys. Res. A 767, 453 (2014)
[6] K.Boretzky et al., Nucl. Instrum. Methods Phys. Res. A 1014 (2021) 165701
