Closing in on the Tip of the CMSSM Stau Coannihilation Strip

Desai, Nishita; Marrouche, Jad; Ellis, John; Luo, Feng

doi:10.1103/PhysRevD.90.055031

Article
Report number	arXiv:1404.5061 ; KCL-PH-TH-2014-13 ; LCTS-2014-13 ; CERN-PH-TH-2014-060 ; KCL-PH-TH-2014-13 ; LCTS-2014-13 ; CERN-PH-TH-2014-060
Title	Closing in on the Tip of the CMSSM Stau Coannihilation Strip
Author(s)	Desai, Nishita (U. Heidelberg, ITP) ; Ellis, John (King's Coll. London ; CERN) ; Luo, Feng (King's Coll. London) ; Marrouche, Jad (CERN)
Publication	2014
Imprint	20 Apr 2014
Number of pages	18
Note	Comments: 19 pages, 6 figures. Fig. 1 and the corresponding text are changed due to the updated ATLAS result (ref.[16]). More details of our simulation are provided in Section 3.1. The caption of Fig. 6 and the corresponding text are changed. Matches the published version 19 pages, 6 figures. Fig. 1 and the corresponding text are changed due to the updated ATLAS result (ref.[16]). More details of our simulation are provided in Section 3.1. The caption of Fig. 6 and the corresponding text are changed. Matches the published version
In:	Phys. Rev. D 90 (2014) 055031
DOI	10.1103/PhysRevD.90.055031
Subject category	Particle Physics - Phenomenology
Abstract	Near the tip of the stau coannihilation strip in the CMSSM with a neutralino LSP, the astrophysical cold dark matter density constraint forces the stau-neutralino mass difference to be small. If this mass difference is smaller than the tau mass, the stau may decay either in the outer part of an LHC detector - the `disappearing track' signature - or be sufficiently long-lived to leave the detector before decaying - the long-lived massive charged-particle signature. We combine searches for these signatures with conventional missing transverse energy searches during LHC Run 1, identifying the small remaining parts of the CMSSM stau coannihilation strip region that have not yet been excluded, and discussing how they may be explored during Run 2 of the LHC.
Copyright/License	Preprint: © 2014-2025 CERN (License: CC-BY-3.0)

$\it Overviews of the regions of the CMSSM parameter space with small mass difference $\Delta m \equiv m_{\tilde \tau}-m_\chi$ for $\tb = 10$ (upper panels) and $\tb = 40$ (lower panels), and for $A_0 = 0$ (left panels) and $2.5 \, m_0$ (right panels). The bands with $\Delta m < m_\tau$ are shaded beige, and the coannihilation strips where $0.125 > \Omega_\chi h^2 > 0.115$ as calculated using {\tt SoftSUSY~3.3.7}~\protect\cite{softsusy} coupled to {\tt MicrOMEGAs 3.5.5}~\protect\cite{micromegas_mssm} are shaded pink. The lower limit on $m_{1/2}$ from the ATLAS $E_T^{miss}$ search during Run~1 at the LHC~\protect\cite{ATLAS20} is represented in each panel by a maroon line, and contours of $m_h$ calculated using {\tt FeynHiggs~2.10.0}~\protect\cite{feynhiggs2.10.0} are shown as green (dashed or dotted) lines. Parameter regions excluded by searches for the direct and total production of metastable charged particles~\protect\cite{CMSex} are shaded darker and lighter blue, respectively, and regions excluded by searches for particles leaving disappearing tracks are shaded grey (see Section~3 for details).$ $\it Left panel: the $\tilde \tau$ lifetime as a function of the ${\tilde \tau_L} - {\tilde \tau_R}$ mixing angle, $\theta_{\tilde \tau}$, for $\Delta m = 1.2, 1.3, \cdots, 1.7$ GeV. Right panel: the $\tilde \tau$ decay branching ratios as functions of $\theta_{\tilde \tau}$ for $\Delta m = 1.5$ GeV. The blue, orange, brown, yellow, and red lines are for the final states with $a_1(1260)$, $\rho(770)$, $\pi$, $\mu$, and $e$, respectively, indicated by the labels adjacent to the corresponding curves. In both panels, a pure bino-like $\chi$ with a mass of 300 GeV is assumed.$ $\it Left panel: the $\tilde \tau$ lifetime as a function of the ${\tilde \tau_L} - {\tilde \tau_R}$ mixing angle, $\theta_{\tilde \tau}$, for $\Delta m = 1.2, 1.3, \cdots, 1.7$ GeV. Right panel: the $\tilde \tau$ decay branching ratios as functions of $\theta_{\tilde \tau}$ for $\Delta m = 1.5$ GeV. The blue, orange, brown, yellow, and red lines are for the final states with $a_1(1260)$, $\rho(770)$, $\pi$, $\mu$, and $e$, respectively, indicated by the labels adjacent to the corresponding curves. In both panels, a pure bino-like $\chi$ with a mass of 300 GeV is assumed.$ Show more plots

Corresponding record in: Inspire

Naspäť k hľadaniu

Záznam vytvorený 2014-05-05, zmenený 2022-01-28

Podobné záznamy

Plný text:

PDF

External link:

Preprint

Pridaj do osobného košíka
Exportuj ako BibTeX, MARC, MARCXML, DC, EndNote, NLM, RefWorks

CERN Document Server

Access articles, reports and multimedia content in HEP

Main menu

CERN Accelerating science