Gamma-ray astronomy

I joined H.E.S.S. in 2012 to broaden my work on multi-messenger analyses, and presented a first joint neutrino and gamma-ray analysis on behalf of the collaboration at the 33rd ICRC in 2013 (arXiv:1307.6074). Besides contributions to the data calibration, I was the corresponding author of the paper on simultaneous H.E.S.S. and RXTE observations of microquasars, and analysed the first H.E.S.S. follow-up of fast radio bursts.

I established and led several topical tasks within H.E.S.S. ("Neutrino alert system", "High-energy neutrino events" and "Gravitational waves"), and in 2014 I was named the official H.E.S.S. multi-messenger contact. Since 2019 I have led the H.E.S.S. transients programme, which takes an increasing share of the total observing time, from gamma-ray bursts to neutrino and gravitational-wave alerts.

Within the CTAO consortium I mainly work on preparing the scientific exploitation. I was a member of the core editorial board of the CTAO Key Science Project on transient sources, focusing on multi-messenger aspects such as how CTAO responds to alerts from neutrino telescopes and gravitational-wave observatories, and I put together the top-level science use cases that define this response. In 2018 and 2019 I convened the "Transients and MWL" science working group. The scheduling tools we develop for H.E.S.S. now prepare CTAO's gravitational-wave follow-up.

Air-shower arrays monitor the gamma-ray sky with particle detectors on the ground, a technique largely complementary to Cherenkov telescopes such as H.E.S.S. and CTAO. I became an associated member of the HAWC collaboration in 2017, contributing to multi-messenger analyses. Following HAWC's success, we started the Southern Gamma-ray Survey Observatory (SGSO) alliance to define and promote a similar observatory in the Southern Hemisphere; it has since become a full scientific collaboration, SWGO.