PKU-SJTU Collider Physics Forum for Junior Scholars (京沪云坛 No.10): Searches for long-lived particles at CMS

by Dr Jingyu Luo (Brown University)

Friday 2 Sep 2022, 10:00 → 11:00 Asia/Shanghai

Online (Cloud)

STJU indico cross-reference: https://indico-tdli.sjtu.edu.cn/event/1257/

Zoom Meeting: 691 8937 4535 (Passcode: 391856)

Biography:

Dr. Jingyu Luo is currently a postdoctoral researcher at Brown University and a CMS LHC Physics Center Distinguished Researcher. As an undergraduate student at University of Science and Technology of China, he worked on event reconstruction at JUNO experiment and four-lepton measurement at ATLAS. He then joined the CMS group at Princeton University for his Ph.D. study.  At Princeton, he focused on searches for long-lived particles (LLPs), for which he has developed and accomplished the full analysis of the Run-2 displaced-jets search at CMS, carrying out everything starting from trigger implementation up to the journal publication. The search provides currently the widest coverage and usually the most restrictive limits on a large variety of LLP models.  He also made major contributions to the luminosity measurements using pixel detector and HF calorimeter, which are the main luminometers of CMS in Run 2. He served as the CMS Beam Radiation Instrumentation and Luminosity (BRIL) detector performance group (DPG) co-convener in 2019-2020. Currently he is focusing on developing new techniques for the displaced-jets search, which will be the foundations of future LLP searches. He is also working on developing new flavor-tagging algorithms using advanced machine-learning tools, search for charged Higgs, and the HL-LHC upgrade of the CMS outer tracker.

Abstract:

The existence of long-lived particles (LLPs) is a common occurrence in both the standard model and beyond-the-standard-model (BSM) scenarios. The BSM scenarios where LLPs can appear are extremely rich, and are deeply connected with some of the most important questions in particle physics, like naturalness, the nature of the dark matter, baryogengesis, and the origin of neutrino mass. In that case, searches for exotic LLPs provide great opportunities of unraveling the mysteries of our universe. At the same time, LLP searches also usually face unique challenges, calling for continuous innovations in triggering, reconstruction, offline analysis, and detector technologies. I will discuss some representative LLP searches from CMS, as well as the future prospects for such searches.