Search for dark matter in association with a leptonically decaying Z boson in ATLAS

Series: 
PPRC Seminars
Speaker: 
Alison Elliot (QMUL)
Host: 
Marcella Bona
Date: 
April 20th, 2018 at 13:30
Room: 
GO Jones Room 410
Abstract: 

This talk describes a search for the invisible decays of dark matter particles produced in association with a Z boson, where the latter decays to a charged lepton pair.   The dataset for this search includes 36.1 1/fb of collisions recorded in 2015 and 2016 at a centre-of-mass energy of 13 TeV in the ATLAS detector at the Large Hadron Collider in Geneva, Switzerland. The invisible particles manifest themselves as missing transverse momentum, or MET, in the detector, while the charged leptons of interest are electron (e+e-) or muon (mu+mu-) pairs.  The search is performed by looking for a deviation from the Standard Model background expectation in the MET distribution.  As no deviations are found, limits are placed on the presented model of dark matter for mediator masses up to 550 GeV and for a range of dark matter masses from 1 to ~200 GeV.

Slides can be found here: https://indico.ph.qmul.ac.uk/indico/conferenceDisplay.py?confId=318