1202.4847 (ATLAS Collaboration)

Search for anomaly-mediated supersymmetry breaking with the ATLAS
detector based on a disappearing-track signature in pp collisions at sqrt(s)
= 7 TeV    [PDF]

ATLAS Collaboration

In models of anomaly-mediated supersymmetry breaking (AMSB), the lightest
chargino is predicted to have a lifetime long enough to be detected in collider
experiments. This letter explores AMSB scenarios in pp collisions at sqrt(s) =
7 TeV by attempting to identify decaying charginos which result in tracks that
appear to have few associated hits in the outer region of the tracking system.
The search was based on data corresponding to an integrated luminosity of 1.02
fb^-1 collected with the ATLAS detector in 2011. The pT spectrum of candidate
tracks is found to be consistent with the expectation from Standard Model
background processes and constraints on the lifetime and the production cross
section were obtained. In the minimal AMSB framework with m_3/2 < 32 TeV, m_0 <
1.5 TeV, tan(beta) = 5 and mu > 0, a chargino having mass below 92 GeV and a
lifetime between 0.5 ns and 2 ns is excluded at 95% confidence level.

View original: http://arxiv.org/abs/1202.4847