PaperPanorama

Nuclear Theory·nucl-th

Thursday·June 5, 2025

11 papers2 primary·9 cross-listed

  1. 01

    The influence of nuclear short range correlations on sub-threshold particle production in proton-nucleus collisions

    Tom Reichert🇩🇪 · Jörg Aichelin🇩🇪

    The apparent production of (multi-)strange baryons and mesons at sub-threshold energies in proton-heavy ion collisions is a consequence of short range correlations (SRC), which have recently been observed in lepton-nucleus scattering. They may enhance the available center of mass energy of individual nucleon-nucleon collisions and allow, therefore, for sub-threshold particle production in proton-nucleus collisions. Calculations demonstrate that SRC enhance the probability for particle production at nominal sub-threshold energies up to a factor of as compared to a simple Fermi gas model. We benchmark the idea by calculating the multiplicity in nominal sub-threshold p+Nb collisions which compare well with the data measured by the HADES collaboration. These findings are of prime relevance for upcoming experiments at the FAIR facility, especially for the study of charmed hadrons.

    nucl-thnucl-exPLB(2026)·5 citations
  2. 02

    Accessing proton number fluctuations in limited regions of phase space

    Piotr Bozek🇵🇱

    In heavy ion collisions particle distributions fluctuate from event to event. It is interesting to study local fluctuations of a specific particle specie, e.g. baryons, in the transverse plane. Fluctuations of the harmonic flow provide an integrated measure of such fluctuations. An alternative approach is to study proton number fluctuations measured in a relatively narrow azimuthal angle window. Due to the transverse flow, particles registered in a narrow azimuthal angle window are emitted predominantly from a region of the fireball located at the same azimuthal angle. Similarly, it is informative to measure the covariance of the number of protons emitted in two opposite windows of azimuthal angles. The main difficulty lies in distinguishing effects of local baryon density fluctuations in the transverse plane from global particle density and collective flow fluctuations. These global volume and flow fluctuations can be estimated using some reference particles, e.g. charged mesons. Reliable estimates of such fluctuations can be constructed both for the second factorial cumulant of the proton number in an azimuthal angle window and for the covariance between two such windows. The simultaneous measurement of both quantities provides a sensitive probe of local baryon number fluctuations superimposed on top of a fluctuating fireball background density.

    nucl-thhep-phnucl-exPRC(2026)·0 citations

Affiliations

first authorsco-authorsvia INSPIRE