37 research outputs found
Neutralinos and Sleptons at the LHC in Light of Muon
We study the muon anomaly in light of neutralino dark matter
and the LHC. We scan the MSSM parameters relevant to and focus on
three distinct cases with different neutralino compositions. We find that the
2 range of requires the smuon () to be
lighter than 500 (1000) GeV for . Correspondingly
the two lightest neutralinos, , have to
be lighter than 300 (650) GeV and 900 (1000) GeV respectively. We
explore the prospects of searching the light smuon and neutralinos at the LHC,
in conjunction with constraints arising from indirect dark matter (DM)
detection experiments. The upcoming run of the LHC will be able to set
CL exclusion limit on ( GeV) and
( GeV) with
GeV at 3000 fb luminosity in multi-lepton + missing energy channel.Comment: 43 pages, 8 figures, 11 tables; v3: Journal matched version - more
discussions and analyses added on non-bino type LS
LHC Constraints on NLSP Gluino and Dark Matter Neutralino in Yukawa Unified Models
The ATLAS experiment has recently presented its search results for final
states containing jets and/or b-jet(s) and missing transverse momentum,
corresponding to an integrated luminosity of 165 pb^{-1}. We employ this data
to constrain a class of supersymmetric SU(4)_c X SU(2)_L X SU(2)_R models with
t-b-\tau Yukawa unification, in which the gluino is the next to lightest
supersymmetric particle (NLSP). The NLSP gluino is slightly (~10-30%) heavier
than the the LSP dark matter neutralino, and it primarily decays into the
latter and a quark-antiquark pair or gluon. We find that NLSP gluino masses
below ~300 GeV are excluded by the ATLAS data. For LSP neutralino mass ~200-300
GeV and \mu>0, where \mu is the coefficient of the MSSM Higgs bilinear term,
the LHC constraints in some cases on the spin-dependent (spin-independent)
neutralino-nucleon cross section are significantly more stringent than the
expected bounds from IceCube DeepCore (Xenon 1T/SuperCDMS). For \mu<0, this
also holds for the spin-dependent cross sections.Comment: 13 pages, 5 figures and 3 table
Reach the Bottom Line of the Sbottom Search
We propose a new search strategy for directly-produced sbottoms at the LHC
with a small mass splitting between the sbottom and its decayed stable
neutralino. Our search strategy is based on boosting sbottoms through an
energetic initial state radiation jet. In the final state, we require a large
missing transverse energy and one or two b-jets besides the initial state
radiation jet. We also define a few kinematic variables to further increase the
discovery reach. For the case that the sbottom mainly decays into the bottom
quark and the stable neutralino, we have found that even for a mass splitting
as small as 10 GeV sbottoms with masses up to around 400 GeV can be excluded at
the 95% confidence level with 20 inverse femtobarn data at the 8 TeV LHC.Comment: 16 pages, 6 figure