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Theses
Dépendance de la production de photons durs avec le paramètre d'impact dans les collisions entre ions lourd aux énergies intermédiaires
Dépendance de la production de photons durs avec le paramètre d'impact dans les collisions entre ions lourd aux énergies intermédiaires
Abstract : In this experimental work, hard photons produced in heavy-ion collisions at intermediate
energies have been used in order to study hot and compressed nuclear matter created in
these collisions. The experiments have been performed at GANIL by the TAPS
collaboration. We have found that bremsstrahlung radiation emitted in np collisions is the
main mechanism of hard-photon production for the whole range of impact parameter.
Moreover, we have observed a substantial decrease of the hardness of hard-photon
spectrum. The BUU model reproduce very well our experimental results, showing that
the hardness of the spectrum reflects, mainly, nuclear-matter compression in the first
stage of the collision. We have developed a new méthode to measure the density of the
nuclear matter created at the beginning of the collision. BUU results and some
experimental evidences point out that a significant contribution of hard photons are
produced in the late stage of the collision : thermal hard photons. These photons are
sensitive to the density oscillation of nuclear matter. Its production corss-section will
constitute a measurement of the compressibility of nuclear matter and its spectrum a
measure of the temperature.
Cited literature [23 references]
http://hal.in2p3.fr/in2p3-00010203
Contributor : Michel Lion <>
Submitted on : Tuesday, February 7, 2017 - 2:49:37 PM
Last modification on : Wednesday, December 2, 2020 - 12:04:03 PM
Long-term archiving on: : Monday, May 8, 2017 - 2:51:39 PM
Contributor : Michel Lion <>
Submitted on : Tuesday, February 7, 2017 - 2:49:37 PM
Last modification on : Wednesday, December 2, 2020 - 12:04:03 PM
Long-term archiving on: : Monday, May 8, 2017 - 2:51:39 PM