Rethinking data-taking at the LHC: specialized data streams from Run 1 to Run 3 and beyond

Abstract
Specialized data-taking and processing techniques are redefining how ATLAS and CMS explore LHC data, extending their physics reach far beyond the original design limits of the detectors. By reshaping how data is collected and analyzed, these approaches are playing an increasingly important role both now and for future operations. They are particularly powerful for exploring new physics at the electroweak scale, where potentially interesting signals can be hidden within overwhelming backgrounds and stringent trigger constraints.
Run 3 strategies have significantly expanded the capabilities of the data acquisition system, building on techniques first introduced in Run 1 and further developed throughout Run 2. Approaches such as data scouting in CMS and trigger-level analysis in ATLAS, as well as data parking in CMS and delayed-stream processing in ATLAS, allow experiments to record more events by reducing event information or deferring full processing when needed. This has opened sensitivity to a wide range of signatures, including low-mass resonances, B-physics, vector-boson fusion processes, long-lived particles, and Higgs boson pair production, while also enabling new approaches such as anomaly detection.
This seminar will review the development of these techniques in ATLAS and CMS, highlight representative physics results, and discuss how they open sensitivity to previously unexplored signatures, with an outlook on their future potential to further broaden the physics reach of the LHC experiments.

Speakers