7,612 research outputs found
The constrained E6SSM
We discuss the predictions of a constrained version of the exceptional
supersymmetric standard model (cE6SSM), with a universal high energy soft
scalar mass, soft trilinear coupling and soft gaugino mass. The spectrum
includes a light gluino, a light wino-like neutralino and chargino pair and a
light bino-like neutralino, with other sparticle masses except the lighter stop
being much heavier. We also discuss scenarios with an extra light exotic colour
triplet of fermions and scalars and a TeV scale Z', which lead to early exotic
physics signals at the LHC.Comment: To appear in proceedings of The 2009 Europhysics Conference on High
Energy Physics, 16-22 July 2009 Krakow, Poland; 4 page
Collapses and revivals of stored orbital angular momentum of light in a cold atomic ensemble
We report on the storage of orbital angular momentum of light in a cold
ensemble of cesium atoms. We employ Bragg diffraction to retrieve the stored
optical information impressed into the atomic coherence by the incident light
fields. The stored information can be manipulated by an applied magnetic field
and we were able to observe collapses and revivals due to the rotation of the
stored atomic Zeeman coherence for times longer than 15 .Comment: Submitted to Physical Review
Intrinsic scatter of caustic masses and hydrostatic bias: An observational study
All estimates of cluster mass have some intrinsic scatter and perhaps some
bias with true mass even in the absence of measurement errors for example
caused by cluster triaxiality and large scale structure. Knowledge of the bias
and scatter values is fundamental for both cluster cosmology and astrophysics.
In this paper we show that the intrinsic scatter of a mass proxy can be
constrained by measurements of the gas fraction because masses with higher
values of intrinsic scatter with true mass produce more scattered gas
fractions. Moreover, the relative bias of two mass estimates can be constrained
by comparing the mean gas fraction at the same (nominal) cluster mass. Our
observational study addresses the scatter between caustic (i.e., dynamically
estimated) and true masses, and the relative bias of caustic and hydrostatic
masses. For these purposes, we used the X-ray Unbiased Cluster Sample, a
cluster sample selected independently from the intracluster medium content with
reliable masses: 34 galaxy clusters in the nearby () Universe,
mostly with , and with caustic masses.
We found a 35\% scatter between caustic and true masses. Furthermore, we found
that the relative bias between caustic and hydrostatic masses is small,
dex, improving upon past measurements. The small scatter found
confirms our previous measurements of a highly variable amount of feedback from
cluster to cluster, which is the cause of the observed large variety of
core-excised X-ray luminosities and gas masses.Comment: A&A, in press, minor language changes from previous versio
Z'-induced Invisible Right-handed Sneutrino Decays at the LHC
The invisible signals of right-handed sneutrino decays originating from a Z'
are analysed at the Large Hadron Collider. The possibility of accessing these
events helps disentangling the B-L extension of Minimal Supersymmetric Standard
Model from more popular scenarios of Supersymmetry. We assess the scope of the
CERN machine in establishing the aforementioned signatures when accompanied by
mono-jet, single-photon or Z-radiation probes through sophisticated
signal-to-background simulations carried out in presence of parton shower,
hadronisation as well as detector effects. We find substantial sensitivity to
all such signals for standard luminosities at Run 2.Comment: 4 pages, 3 figure
Active templates: Manipulating pointers with pictures
Active templates are a semi-automatic visual mechanism for generating algorithms for manipulating pointer-based data structures. The programmer creates a picture showing the affected part of a data structure before and after a general-case manipulation. Code for the operation is compiled directly from the picture, which also provides the development environment with enough information to generate, automatically, a series of templates for other similar pictures, each describing a different configuration which the data structure may possess. The programmer completes the algorithm by creating matching after-pictures for each of these cases.
At every stage, most of the picture-generation is automatic. Much of the tedious detail of conventional pointer-based data-structure manipulation, such as maintenance of current pointers, is unnecessary in a system based on active templates
NMSSM Higgs Discovery at the LHC
We demonstrate that Higgs discovery at the LHC is possible in the context of
the NMSSM even for those scenarios such that the only strongly produced Higgs
boson is a very SM-like CP-even scalar which decays almost entirely to a pair
of relatvely light CP-odd states. In combination with other search channels, we
are on the verge of demonstrating that detection of at least one of the NMSSM
Higgs bosons is guaranteed at the LHC for accumulated luminosity of .Comment: 8 pages, 1 figure, to appear in the Proceedings of the Les Houches
Workshop 2003: ``Physics at TeV Colliders'
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