1,163 research outputs found
Higgs-Pair Production and Measurement of the Triscalar Coupling at LHC(8,14)
We simulate the measurement of the triscalar Higgs coupling at LHC(8,14) via
pair production of h(125 GeV). We find that the most promising hh final state
is bb gamma gamma. We account for deviations of the triscalar coupling from its
SM value and study the effects of this coupling on the hh cross-section and
distributions with cut-based and multivariate methods. Our fit to the hh
production matrix element at LHC(14) with 3 ab^-1 yields a 40% uncertainty on
this coupling in the SM and a range of 25-80% uncertainties for non-SM values.Comment: 4 pages, 7 page
Calculation of W b bbar Production via Double Parton Scattering at the LHC
We investigate the potential to observe double parton scattering at the Large
Hadron Collider in p p -> W b bbar X -> l nu b bbar X at 7 TeV. Our analysis
tests the efficacy of several kinematic variables in isolating the double
parton process of interest from the single parton process and relevant
backgrounds for the first 10 inverse fb of integrated luminosity. These
variables are constructed to expose the independent nature of the two
subprocesses in double parton scattering, pp -> l nu X and pp -> b bbar X. We
use next-to-leading order perturbative predictions for the double parton and
single parton scattering components of W b bbar and for the pertinent
backgrounds. The next-to-leading order contributions are important for a proper
description of some of the observables we compute. We find that the double
parton process can be identified and measured with significance S/sqrt(B) ~ 10,
provided the double parton scattering effective cross section sigma_{eff} ~ 12
mb.Comment: 21 pages, 9 figures; v2: improved presentation and figures, version
published in Phys. Rev.
Gamma-ray lines and One-Loop Continuum from s-channel Dark Matter Annihilations
The era of indirect detection searches for dark matter has begun, with the
sensitivities of gamma-ray detectors now approaching the parameter space
relevant for weakly interacting massive particles. In particular, gamma ray
lines would be smoking gun signatures of dark matter annihilation, although
they are typically suppressed compared to the continuum. In this paper, we pay
particular attention to the 1-loop continuum generated together with the
gamma-ray lines and investigate under which conditions a dark matter model can
naturally lead to a line signal that is relatively enhanced. We study generic
classes of models in which DM is a fermion that annihilates through an
s-channel mediator which is either a vector or scalar and identify the coupling
and mass conditions under which large line signals occur. We focus on the
"forbidden channel mechanism" advocated a few years ago in the "Higgs in space"
scenario for which tree level annihilation is kinematically forbidden today.
Detailed calculations of all 1-loop annihilation channels are provided. We
single out very simple models with a large line over continuum ratio and
present general predictions for a large range of WIMP masses that are relevant
not only for Fermi and Hess II but also for the next generation of telescopes
such as CTA and Gamma-400. Constraints from the relic abundance, direct
detection and collider bounds are also discussed.Comment: 32 pages, 13 figures; v2: minor clarifications, summary paragraph
added; v3: matches published version, minor clarifications, results unchange
Higgs Boson Search Sensitivity in the Dilepton Decay Mode at and 10 TeV
Prospects for discovery of the standard model Higgs boson are examined at
center of mass energies of and TeV at the CERN Large Hadron Collider.
We perform a simulation of the signal and principal backgrounds for Higgs boson
production and decay in the dilepton mode, finding good agreement
with the ATLAS and CMS collaboration estimates of signal significance at 14 TeV
for Higgs boson masses near ~GeV. At the lower energy of ~TeV,
using the same analysis cuts as these collaborations, we compute expected
signal sensitivities of about standard deviations ('s) at ~GeV in the ATLAS case, and about 3.6~ in the CMS case for
~fb of integrated luminosity. Integrated luminosities of
8~ and 3~ are needed in the ATLAS case at and
~TeV, respectively, for level discovery. In the CMS case, the
numbers are 2~ and 1~ at and ~TeV. Our
different stated expectations for the two experiments arise from the more
restrictive analysis cuts in the CMS case. Recast as exclusion limits, our
results show that with of integrated luminosity at 7~TeV, the
LHC may be able to exclude values in the range 160 to 180~GeV provided no
signal is seen.Comment: 29 pages, 8 figures. New results on estimated discovery reach for
both CMS and ATLAS, as well as exclusion limits, along with comparisons with
Tevatron possibilities. References added
Current and future approaches to classify VUSs in LGMD-related genes
Next-generation sequencing (NGS) has revealed large numbers of genetic variants in LGMD-related genes, with most of them classified as variants of uncertain significance (VUSs). VUSs are genetic changes with unknown pathological impact and present a major challenge in genetic test interpretation and disease diagnosis. Understanding the phenotypic consequences of VUSs can provide clinical guidance regarding LGMD risk and therapy. In this review, we provide a brief overview of the subtypes of LGMD, disease diagnosis, current classification systems for investigating VUSs, and a potential deep mutational scanning approach to classify VUSs in LGMD-related genes
Prescriptions and proscriptions: moralising sleep medicines
This work was carried out with colleagues at the University of Warwick and Royal Holloway, University of London.
Open access articleThe pharmaceuticalisation of sleep is a contentious issue. Sleep medicines get a‘bad press’due to their potential for dependence and other side effects, including studies reporting increased mortality risks for long-term users. Yet relatively little qualitative social science research has been conducted into how people understandand negotiate their use/non-use of sleep medicines in the context of their everyday lives. This paper draws on focus group data collected in the UK to elicit collective views on and experiences of prescription hypnotics across different social contexts.Respondents, we show, drew on a range of moral repertoires which allowed them to present themselves and their relationships with hypnotics in different ways. Six distinct repertoires about hypnotic use are identified in this regard: the ‘deserving’ patient, the ‘responsible’ user, the ‘compliant’ patient, the ‘addict’, the ‘sinful’ user and the ‘noble’ non user. These users and non-users are constructed drawing on cross-cutting themes of addiction and control, ambivalence and reflexivity. Such issues are in turn discussed in relation to recent sociological debates on the pharmaceuticalisation/de-pharmaceuticalisation of everyday life and the consumption of medicines in the UK today
The WIMP Forest: Indirect Detection of a Chiral Square
The spectrum of photons arising from WIMP annihilation carries a detailed
imprint of the structure of the dark sector. In particular, loop-level
annihilations into a photon and another boson can in principle lead to a series
of lines (a WIMP forest) at energies up to the WIMP mass. A specific model
which illustrates this feature nicely is a theory of two universal extra
dimensions compactified on a chiral square. Aside from the continuum emission,
which is a generic prediction of most dark matter candidates, we find a
"forest" of prominent annihilation lines that, after convolution with the
angular resolution of current experiments, leads to a distinctive (2-bump plus
continuum) spectrum, which may be visible in the near future with the Fermi
Gamma-Ray Space Telescope (formerly known as GLAST).Comment: 11 pages, 4 figure
Ethics, evidence based sports medicine, and the use of platelet rich plasma in the English Premier League
The use of platelet rich plasma (PRP) as a novel treatment is discussed in the context of a qualitative research study comprising 38 interviews with sports medicine practitioners and other stakeholders working within the English Premier League during the 2013-16 seasons. Analysis of the data produced several overarching themes: conservatism versus experimentalism in medical attitudes; therapy perspectives divergence; conflicting versions of appropriate evidence; subcultures; community beliefs/practices; and negotiation of medical decision-making. The contested evidence base for the efficacy of PRP is presented in the context of a broader professional shift towards evidence based medicine within sports medicine. Many of the participants while accepting this shift are still committed to casuistic practices where clinical judgment is flexible and does not recognize a context-free hierarchy of evidentiary standards to ethically justifiable practice. We also discuss a tendency in the data collected to consider the use of deceptive, placebo-like, practices among the clinician participants that challenge dominant understandings of informed consent in medical ethics. We conclude that the complex relation between evidence and ethics requires greater critical scrutiny for this emerging specialism within the medical community
Economic Contribution of Maine’s Food Industry
Using existing state and federal data and Maine IMPLAN, a state-of-the-art economic modeling system, the authors present an overview of the economic contributions of Maine’s food industry. This includes food makers (farms, fisheries, food-processing companies) and food sellers (grocery stores, direct sales, restaurants). Each play a unique, but interconnected, role in the Maine economy and add up to significant economic impact
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