During his time as a Ph.D. student in Tübingen, Daniel has been responsible for the actuator system of the large (28 m) H.E.S.S. II telescope, CT5, including maintenance, tests and alignment campaigns, and the corresponding analysis activities. He also prepared and performed all necessary actions concerning the mirror alignment system so that the collaboration can now point CT5 in reverse mode significantly faster to a new source than in traditional slewing modes. This is of great value specifically for GRB observations. Daniel also happily took over the task of monitoring the point spread function of the 12-m telescpoes CT1-4 after the University of Hamburg stepped down from that responsibility. In 2017, Daniel took over the responsibility of leading the effort to exchange all mirrors of CT3 with spare mirrors. This comprised both the on-site hardware as well as the control and analysis software of the alignment system. He furthermore led the maintenance of the mirror test facility, and, in addition, contributed significantly to analysis tasks for the H.E.S.S. I legacy paper on TeV supernova remnant shell candidates.
H.E.S.S. Prize Hall of Fame
The H.E.S.S. Prize
With the H.E.S.S. Prize, the collaboration acknowledges young scientists (PhD, postdoc, junior staff) who made outstanding service contributions to the experiment. Such contributions might range from hardware maintenance to various aspects of data handling including outstanding analyses (the development of a new analysis technique allowing a measurement not possible before) or a key contribution to an important scientific discovery. The prize is awarded at every collaboration meeting through a confidential vote by the Collaboration Board.
List of H.E.S.S. Prize Winners
Markus Holler
Markus Holler’s most outstanding contribution to H.E.S.S. was the tremendous work he did in the development of a new paradigm, namely the Run Wise Simulations. This new simulation framework not only paves the way towards improved control of systematic effects, thereby opening new science cases such as the measurement of the extension of the Crab Nebula, but will very likely have a very large impact on the future of VHE gamma‐ray astronomy in general. Markus Holler was hired primarily for an ambitious project aiming at measuring the Galactic Diffuse Emission in VHE gamma‐rays. This is very challenging and requires in particular to significantly improve the understanding the of instrumental background systematics, and thus to develop new background determination/subtraction techniques. A more precise simulation of the instrument was quickly identified as the central element in these investigations. Markus led this task with enthusiasm, pertinacity and efficiency, and with a great care of precision. He successively incorporated many effects such as non‐operational pixels, actual calibration, effect of telescope dead‐time on event multiplicity, and actual tracking of the telescopes. He devoted a huge amount of work on the comparison between Monte Carlo and real data. At the end, we have now a much more precise simulation of the instrument, which opens up new possibilities previously out of reach: the almost perfect understanding of the PSF, for instance, enables extension measurements with great confidence (e.g. Crab Nebula). Last but not least, the success of this approach raised large interest in the community, as future instruments such as CTA will probably have to adopt Run Wise Simulations for optimal scientific return. In addition, Markus is serving as deputy‐convener of the Analysis & Reconstruction WG. He provided many cross‐check analyses and contributed to an incredibly large number of tasks. He is also very well considered in the collaboration for his kindness, his abilities to share his work and willingness to help.
Gianluca Giavitto
Gianluca was awarded the H.E.S.S. prize especially for the upgrade of the H.E.S.S.-I cameras. He has worked extensively on both the software and hardware of the cameras during their development and integration, becoming the de facto technical coordinator of the upgrade project. Moreover, he has greatly contributed to the Science output of the large (28 m) telescope of H.E.S.S. Phase II by participating in the discovery of the pulsed emission from the Vela Pulsar.
Heike Prokoph
Heike made outstanding contributions to the H.E.S.S. experiment on topics bridging various working groups, from instrument, via analysis and reconstruction to the Extragalactic science working group. She was co-leading an effort to solve a large discrepancy at low energies between the two Monte-Carlo simulation chains that are used in H.E.S.S. Understanding this discrepancy ultimately allowed us to analyse and publish the high-impact paper on the Vela Pulsar emission observed with the H.E.S.S.-II telescope. Heike also shaped the H.E.S.S. target-of-opportunity programme in a major way, which is now one of the cornerstones of the H.E.S.S. science operations in the multi-messenger era.
Stefan Ohm
Stefan Ohm has been a highly valued and active contributor to H.E.S.S. data analysis, simulations and astrophysics since 2007, working at the Max Planck Institute for Nuclear Physics in Heidelberg, the University of Leicester, and since 2014 at DESY Zeuthen. Stefan’s many contributions include improvements to the techniques for background rejection, improvements to the real time science data analysis for H.E.S.S. and gamma-ray studies of many systems involving massive stars and/or star-forming regions.
Vincent Marandon
Vincent Marandon has been the main responsible person for the calibration of H.E.S.S. data in Germany, which is crucially important for data analysis from both H.E.S.S. I and H.E.S.S. II. Vincent has spent 3 years of full time work in Heidelberg on maintaining the calibration of H.E.S.S. I data as well as defining new calibration strategies for H.E.S.S. II data. Over this time, Vincent has almost single handedly developed the calibration of H.E.S.S. II data in Germany, working closely with the French groups to try to identify issues with the new hardware along the way, including rapid variation in pedestal in some regions of the camera. It is safe to say that without Vincent’s hard work no analysis of H.E.S.S. II data would be possible with the German calibration. In addition to his technical work, Vincent has worked on a wide range of scientific topics. These include work on the H.E.S.S. galactic plane survey, as well as exploiting this data for the Supernova Remnant and Pulsar Wind Nebula population studies. He has also made detailed comparisons between the results of the Heidelberg analysis chain and other analysis chains while cross checking the analysis of the supernova remnants W49B and W51C.