Dark Matter @ LHC 2019 (DM@LHC)

[YSF] Search for the compressed SUSY in stau-neutralino coannihilation region with a soft tau lepton and ISR jets

14 Aug 2019, 15:15

10m

Walker-Ames (Kane Hall 225)

Young Scientist Forum Collider Search: Higgs and SUSY

Speaker

Savanna Rae Starko (Vanderbilt University (US))

Description

A search for compressed supersymmetry in the stau-neutralino ($\tilde{\tau }{\tilde{\chi }}_1^0$) coannihilation region is presented. The search targets final states with exactly one low-energy (``soft'') hadronically-decaying $\tau$ lepton and large missing transverse momentum (${\overrightarrow{E}}_T^{miss}$) due to the natural kinematic boost from a high transverse momentum jet from initial state radiation (ISR). The data sample corresponds to an integrated luminosity of 77.2 fb${}^{-1}$ of proton-proton collisions at $\sqrt{s}=13$ TeV collected with CMS detector at the CERN LHC in 2016 and 2017. The distribution of the transverse mass between the ${\tau }_h$ and the ${\overrightarrow{E}}_T^{miss}$ is found to be consistent with the standard model predictions. Upper limits are set on the cross section for chargino (${\tilde{\chi }}_1^{\pm }$) and neutralino (${\tilde{\chi }}_2^0$) production with an associated ISR jet. For a compressed mass spectrum scenario in which the mass difference between the ${\tilde{\chi }}_1^0$ and the ${\tilde{\chi }}_1^{\pm }$ is 50 GeV, an upper limit of 290 GeV is set on the mass of the ${\tilde{\chi }}_1^{\pm }$, which exceeds the sensitivity obtained by other $\tilde{\tau }$ searches to date. Finally, the results are also interpreted considering direct production of $\tilde{\tau }$ pairs with associated ISR jets.

Presentation materials

isrstau_dmlhc2019_sstarko.pdf