It was with great sadness that we learned that our colleague Oliver Busch – TRD Technical Coordinator, former PWG-JE convenor, and longtime ALICE collaborator – passed away on March 31st, one week prior to his 42ndbirthday and one month before moving to Japan to take up a tenured professorship at the University of Tsukuba.
Oliver started his career in heavy-ion physics during his undergraduate studies at the Technical University of Darmstadt and GSI, which also included a year abroad at the University of Bordeaux (France). His Diploma thesis, completed in 2002, consisted of a benchmark measurement for the design of the ALICE Transition Radiation Detector (TRD), the number and spectrum of transition radiation photons generated by a passing electron. For his doctoral thesis, supervised by Peter Braun-Munzinger, Oliver developed an alternative method for the analysis of low-mass dielectron production in the CERES experiment. Even as a student he already impressed many of his colleagues with his deep and detailed understanding of theoretical concepts in nuclear and particle physics. After his doctoral defense in late 2007 he moved to the University of Heidelberg, where he held a post-doc position until 2014.
It was in Heidelberg that Oliver developed his passion for jet physics, which would be the main focus of his research for the rest of his career. He was particularly interested in the fragmentation and hadrochemistry of jets, and mentored multiple students on analyses of identified particle production associated with hard scatterings. In recognition of his contributions to the study of jets in ALICE, he became PWG-JE convenor in 2014, a position that he held for three years. He also remained deeply involved in the TRD project, in particular spending a decade acting as the DCS system coordinator, in charge of the most complex detector control system in the experiment. Not big on formality, and with his typical humility, he said he just enjoyed “being the DCS guy.” Immediately after concluding his PWG convenorship in 2017, he took on the role of Technical Coordinator of the TRD project.
In late 2014 Oliver was hired as a tenure-track assistant professor at the University of Tsukuba (Japan), as part of a program geared towards attracting international faculty to Japanese universities. While still based in Heidelberg, he spent several months per year in Japan, and embarked on learning Japanese with the same intense focus that he applied to his other interests. At the end of 2017 Oliver was awarded tenure in Tsukuba, and was looking forward to starting a new chapter in his career by moving to Japan in May 2018.
Outside of the office, Oliver was passionate about music, art, and literature, and was an accomplished horn player in local orchestras in Mannheim and Darmstadt. While he was by nature reserved and private, mentioning one of his favorite topics – physics or music – would spark an enthusiastic discussion over any lunch table or in the car on the way to CERN.
Oliver was always positive, infinitely patient, helpful, reliable, calm, quiet, and kind. Despite his many responsibilities, he always found the time to help his colleagues or discuss ideas for current and future analyses, conversations that were particularly inspiring and interesting because he was so widely-read and his knowledge of our field was so extensive. His deep insight and expertise meant that he could ask questions that were tough for us to answer, but he always asked with kindness, and his questions and suggestions came from a place of wanting to improve his understanding, and of wanting to help improve our work. Oliver showed us on a daily basis that it is possible to be a very successful and well-respected physicist, while always keeping a positive attitude and a good spirit, and supporting those around him. He succeeded while also lifting up his fellow colleagues and students, and we are all better physicists because of it.