981 research outputs found
SO(10) SUSY GUTs with mainly axion cold dark matter: implications for cosmology and colliders
Supersymmetric grand unified theories based on the gauge group SO(10) are
highly motivated. In the simplest models, one expects t-b-\tau Yukawa coupling
unification, in addition to gauge, matter and Higgs unification. Yukawa
unification only occurs with very special GUT scale boundary conditions,
leading to a spectra with ~10 TeV first and second generation scalars,
TeV-scale third generation scalars, and light gauginos. The relic density of
neutralino cold dark matter is calculated to be 10^2-10^4 times higher than
observation. If we extend the theory with the PQWW solution to the strong CP
problem, then instead a mixture of axions and axinos comprises the dark matter,
with the measured abundance. Such a solution solves several cosmological
problems. We predict a rather light gluino with m(gluino)~300-500 GeV that
should be visible in either Tevatron or forthcoming LHC run 1 data. We would
also expect ultimately a positive result from relic axion search experiments.Comment: 6 pages plus 2 .eps figures; invited talk given at Axions 2010
meeting, University of Florida, Jan. 15-17, 201
Computational Tools for Supersymmetry Calculations
I present a brief overview of a variety of computational tools for
supersymmetry calculations, including: spectrum generators, cross section and
branching fraction calculators, low energy constraints, general purpose event
generators, matrix element event generators, SUSY dark matter codes, parameter
extraction codes and Les Houches interface tools.Comment: Chapter to appear in Perspectives on Supersymmetry, edited by G.
Kane; 23 pages including one .eps figur
Supersymmetry and Dark Matter post LHC8: why we may expect both axion and WIMP detection
In the post-LHC8 era, it is perceived that what is left of SUSY model
parameter space is highly finetuned in the EW sector (EWFT). We discuss how
conventional measures overestimate EWFT in SUSY theory. Radiatively-driven
natural SUSY (RNS) models maintain the SUSY GUT paradigm with low EWFT at 10%
level, but are characterized by light higgsinos ~100-300 GeV and a thermal
underabundance of WIMP dark matter. Implementing the SUSY DFSZ solution to the
strong CP problem explains the small \mu parameter but indicates dark matter
should be comprised mainly of axions with a small admixture of higgsino-like
WIMPs. While RNS might escape LHC14 searches, we would expect ultimately direct
detection of both WIMPs and axions. An e^+e^- collider with \sqrt{s} ~ 500-600
GeV should provide a thorough search for the predicted light higgsinos.Comment: 11 pages; 5 figures: Talk given at Particle Physics and Cosmology
meeting (PPC2013), July 8, 2013, Deadwood, South Dakot
SUSY backgrounds to Standard Model calibration processes at the LHC
One of the first orders of business for LHC experiments after beam turn-on
will be to calibrate the detectors using well understood Standard Model (SM)
processes such as W and Z production and ttbar production. These familiar SM
processes can be used to calibrate the electromagnetic and hadronic
calorimeters, and also to calibrate the associated missing transverse energy
signal. However, the presence of new physics may already affect the results
coming from these standard benchmark processes. We show that the presence of
relatively low mass supersymmetry (SUSY) particles may give rise to significant
deviations from SM predictions of Z+jets and W+jets events for jet multiplicity
or , respectively. Furthermore, the presence of low mass SUSY
may cause non-standard deviations to appear in top quark invariant and
transverse mass distributions. Thus, effects that might be construed as
detector mal-performance could in fact be the presence of new physics. We
advocate several methods to check when new physics might be present within SM
calibration data.Comment: 14 pages, 6 figures, 3 table
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