125,505 research outputs found
Electroweakino constraints from LHC data
We investigate the sensitivity of existing LHC searches to the charginos and
neutralinos of the MSSM when all the other superpartners are decoupled. In this
limit, the underlying parameter space reduces to a simple four-dimensional set
. We examine the constraints placed on this
parameter space by a broad range of LHC searches taking into account the full
set of relevant production and decay channels. We find that the exclusions
implied by these searches exceed existing limits from LEP only for smaller
values of the Bino mass GeV. Our results have implications
for MSSM dark matter and electroweak baryogenesis.Comment: 30 pages, 15 figure
XB-70 flight test data comparisons with simulation predictions of inlet unstart and buzz
XB-70 flight test data comparison with simulated predictions of inlet unstart and buz
Extraction of black hole coalescence waveforms from noisy data
We describe an independent analysis of LIGO data for black hole coalescence
events. Gravitational wave strain waveforms are extracted directly from the
data using a filtering method that exploits the observed or expected
time-dependent frequency content. Statistical analysis of residual noise, after
filtering out spectral peaks (and considering finite bandwidth), shows no
evidence of non-Gaussian behaviour. There is also no evidence of anomalous
causal correlation between noise signals at the Hanford and Livingston sites.
The extracted waveforms are consistent with black hole coalescence template
waveforms provided by LIGO. Simulated events, with known signals injected into
real noise, are used to determine uncertainties due to residual noise and
demonstrate that our results are unbiased. Conceptual and numerical differences
between our RMS signal-to-noise ratios (SNRs) and the published matched-filter
detection SNRs are discussed.Comment: 15 pages, 11 figures. Version accepted for publicatio
Digital video display system
System displays image data in real time on 120,000-element raster scan with 2, 4, or 8 shades of grey. Designed for displaying planetary range Doppler data, system can be used for X-Y plotting, displaying alphanumerics, and providing image animation
Recognition of finite exceptional groups of Lie type
Let be a prime power and let be an absolutely irreducible subgroup of
, where is a finite field of the same characteristic as \F_q,
the field of elements. Assume that , a quasisimple group of
exceptional Lie type over \F_q which is neither a Suzuki nor a Ree group. We
present a Las Vegas algorithm that constructs an isomorphism from to the
standard copy of . If with even, then the
algorithm runs in polynomial time, subject to the existence of a discrete log
oracle
Extending LHC Coverage to Light Pseudoscalar Mediators and Coy Dark Sectors
Many dark matter models involving weakly interacting massive particles
(WIMPs) feature new, relatively light pseudoscalars that mediate dark matter
pair annihilation into Standard Model fermions. In particular, simple models of
this type can explain the gamma ray excess originating in the Galactic Center
as observed by the Fermi Large Area Telescope. In many cases the pseudoscalar's
branching ratio into WIMPs is suppressed, making these states challenging to
detect at colliders through standard dark matter searches. Here, we study the
prospects for observing these light mediator states at the LHC without
exploiting missing energy techniques. While existing searches effectively probe
pseudoscalars with masses between 5 - 14 GeV and above 90 GeV, the LHC reach
can be extended to cover much of the interesting parameter space in the
intermediate 20 - 80 GeV mass range in which the mediator can have appreciable
Yukawa-like couplings to Standard Model fermions but would have escaped
detection by LEP and other experiments. Models explaining the Galactic Center
excess via a light pseudoscalar mediator can give rise to a promising signal in
this regime through the associated production of the mediator with bottom
quarks while satisfying all other existing constraints. We perform an analysis
of the backgrounds and trigger efficiencies, detailing the cuts that can be
used to extract the signal. A significant portion of the otherwise
unconstrained parameter space of these models can be conclusively tested at the
13 TeV LHC with 100 fb, and we encourage the ATLAS and CMS
collaborations to extend their existing searches to this mass range.Comment: 27 pages + 3 appendices, 20 figures, 7 table
Communications link for SDS 900 series computers
High speed, self-clocking single channel control and data link apparatus interfaces between two computers. This combined system reduces data errors
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