Dark matter direct detection and development of sub-10 picosecond Time-of-Flight detector

by Dr Junhui Liao

Wednesday 26 Sep 2018, 10:00 → 11:00 Asia/Shanghai

B326 (IHEP)

I will be talking about Dark Matter (DM) direct detection and the R&D for a sub-10 picosecond (ps) Time of Flight (ToF) detector. DM is one of the most important questions to be understood and answered in fundamental physics. Among other DM candidates, Weakly Interactive Massive Particles (WIMPs) is the most discussed one. WIMPs direct detection is a research of multi-disciplines which wraps astrophysics, particle physics and nuclear physics together and able to explore the un-touched region of the interaction between WIMPs and nucleons in a way other methods like indirect detection and the search on colliders can't reach. In this section, I will be firstly reviewing the search of DM: the evidence of its existence, the strategy of detection, the current results from various experiments etc; secondly, two DM direct experiments will be addressed in detail: DArk Matter In CCDs (DAMIC) and LUX-ZEPLIN (LZ) which hunt for low-mass ~ (1 - 10) GeV/c^2 and high-mass ~ (10 - 1000) GeV/c^2 WIMPs, respectively. For DAMIC, I will be talking about the quenching factor calibration for a silicon detector and the understanding for the interaction between WIMPs and nucleons under the context of Effective Field Theory (EFT). LZ is the most sensitive WIMPs searching detector at the stage of construction and has been fully funded by Department of Energy (DOE), USA. I will introduce the project a little bit, the progress of the assembly of PMT arrays at Brown and the Geant simulation for a calibration of Liquid Xenon (LXe) with 300 keV neutrons. The sub-10 ps ToF originated from the ATLAS-CMS joint experiment, FP420, which was a search of forward physics at 420 meters away from the Interaction Points (IP) of both detectors. I will introduce the detector and its laser tests in the lab of UCLouvain and beam tests at CERN. With two independent analyzing methods being applied to beam tests data, we demonstrated confidently an individual detector is capable of achieving ~ 8.0 ps timing resolution which is the best performance among similar gas detectors all over the world ever since. Brief CV of the speaker: Mar 2018 - present, Senior scientist, Brown University. Feb 2017 - Feb 2018, post doc, Brown University. July 2013 - Dec 2016, PhD, University of Zurich, Switzerland. Mar 2014 - Dec 2015, visiting scholar, Fermilab. Mar 2009 - Jan 2013, Research assistant, UCLouvain, Belgium. Sep 2005 - Mar 2009, Joint master student and primary researcher, EPC, IHEP. Sep 2007 - Dec 2007, visiting scholar, LNF, INFN

Slides IHEP_Talk_Sep262018_JunhuiLiao.pdf