Garchinger Maier-Leibnitz-Kolloquium: ALICE determines the transparency of our galaxy to the passage of antihelium nuclei

by Laura Serksnyte (Physik Department E49, TUM)

Thursday Jun 22, 2023, 4:15 PM → 5:15 PM Europe/Berlin

Lecture Hall, ground floor (west) (LMU building, Am Coulombwall 1, campus Garching)

In the past decade, the ALICE Collaboration has measured the production of light
(anti)nuclei very precisely in small and large collision systems. The most recent development in this field concerns the measurements of the momentum-dependent inelastic cross sections of antideuterons and antihelium-3 nuclei employing the ALICE detector material as a target. The antihelium-3 inelastic cross sections have been obtained by applying the antimatter-to-matter ratio and TOF-to-TPC matching methods in pp and Pb-Pb collisions, respectively. These  measured inelastic cross sections have been implemented in the GALPROP propagation model to estimate the loss antihelium-3 flux due to inelastic interactions with the interstellar medium. Indeed, some dark matter candidates, such as the Weakly Interacting Massive Particles (WIMPs), are expected to annihilate in our galaxy and produce, among other particles, light antinuclei, which can be observed as cosmic rays. However, the same antinuclei can also be produced in ordinary cosmic ray collisions with the interstellar gas. Thus, precise modelling of signal and background cosmic ray fluxes, including the inelastic losses in the interstellar medium, is required to draw conclusions from future measurements expected by the AMS and GAPS experiments.

Hybrid access via ZOOM:
https://lmu-munich.zoom.us/j/98457332925?pwd=TWc3V1JkSHpyOTBPQVlMelhuNnZ1dz09
Meeting ID: 984 5733 2925
Passcode: 979953

kolloquium-22-06-23.pdf