6,401 research outputs found
as a discovery tool for bosons at the LHC
The Forward-Backward Asymmetry (AFB) in physics is commonly only
perceived as the observable which possibly allows one to interpret a
signal by distinguishing different models of such (heavy) spin-1 bosons. In
this article, we examine the potential of AFB in setting bounds on or even
discovering a at the Large Hadron Collider (LHC) and show that it
might be a powerful tool for this purpose. We analyze two different scenarios:
s with a narrow and wide width, respectively. We find that in both
cases AFB can complement the cross section in accessing signals.Comment: arXiv admin note: substantial text overlap with arXiv:1503.0267
Phenomenology of the minimal B-L extension of the Standard Model
We present the Large Hadron Collider (LHC) discovery potential in the
and heavy neutrino sectors of a enlarged Standard Model also
encompassing three heavy Majorana neutrinos. This model exhibits novel
signatures at the LHC, the most interesting arising from a decay chain
involving heavy neutrinos, eventually decaying into leptons and jets. In
particular, this signature allows one to measure the and heavy neutrino
masses involved. In addition, over a large region of parameter space, the heavy
neutrinos are rather long-lived particles producing distinctive displaced
vertices that can be seen in the detectors. Lastly, the simultaneous
measurement of both the heavy neutrino mass and decay length enables an
estimate of the absolute mass of the parent light neutrino. For completeness,
we will also compare the LHC and a future Linear Collider (LC) discovery
potentials.Comment: 4 pages, no figures. LaTeX. Talk given at "The 2009 Europhysics
Conference on High Energy Physics", Krakow, Poland, July 16-22, 200
A smoking gun signature of the 3HDM
We analyse new signals of a 3-Higgs Doublet Model (3HDM) at the Large Hadron
Collider (LHC) where only one doublet acquires a Vacuum Expectation Value
(VEV), preserving a parity. The other two doublets are \textit{inert} and
do not develop a VEV, leading to a \textit{dark scalar sector} controlled by
, with the lightest CP-even dark scalar being the Dark Matter (DM)
candidate. This leads to the loop induced decay of the next-to-lightest scalar,
(), mediated by both dark CP-odd
neutral and charged scalars. This is a smoking-gun signal of the 3HDM since it
is not allowed in the 2-Higgs Doublet Model (2HDM) with one inert doublet and
is expected to be important when and are close in mass. In
practice, this signature can be observed in the cascade decay of the SM-like
Higgs boson, into two DM particles and
di-leptons or into two
DM particles and four-leptons, where is produced from gluon-gluon Fusion.
In order to test the feasibility of these channels at the LHC, we devise some
benchmarks, compliant with collider, DM and cosmological data, for which the
interplay between these production and decay modes is discussed. In particular,
we show that the resulting detector signatures, \Et \ell \bar \ell or \Et
\ell \bar \ell \ell \bar \ell, with the invariant mass of
pairs much smaller than , can potentially be extracted already from Run 3
data and at the High-Luminosity phase of the LHC.Comment: 27 pages, 13 figures. arXiv admin note: text overlap with
arXiv:1712.0959
Exploring Sensitivity to NMSSM Signatures with Low Missing Transverse Energy at the LHC
We examine scenarios in the Next-to-Minimal Supersymmetric Standard Model
(NMSSM), where pair-produced squarks and gluinos decay via two cascades, each
ending in a stable neutralino as Lightest Supersymmetric Particle (LSP) and a
Standard Model (SM)-like Higgs boson, with mass spectra such that the missing
transverse energy, , is very small. Performing
two-dimensional parameter scans and focusing on the hadronic decay giving a final state
we explore the sensitivity of a current LHC general-purpose
jets+ analysis to such scenarios.Comment: 17 pages, 17 figures, 6 table
Tensor analyzing powers for Li7 breakup
Differential cross sections and T20 and 20TT analyzing powers have been measured for 70 MeV Li7 breakup into the particle plus triton channel, on a Sn120 target. Measurements were made for both continuum breakup and sequential breakup via the 4.63 MeV state in Li7. The T20 data for the continuum breakup do not agree with a semiclassical Coulomb model, indicating that the breakup at small angles does not proceed solely via a Coulomb force. The data generally show a somewhat better agreement with continuum discretized coupled channels calculations, indicating the importance of the nuclear force and channel coupling in the reaction mechanism. © 1995 The American Physical Society
Run 2 Upgrades to the CMS Level-1 Calorimeter Trigger
The CMS Level-1 calorimeter trigger is being upgraded in two stages to
maintain performance as the LHC increases pile-up and instantaneous luminosity
in its second run. In the first stage, improved algorithms including
event-by-event pile-up corrections are used. New algorithms for heavy ion
running have also been developed. In the second stage, higher granularity
inputs and a time-multiplexed approach allow for improved position and energy
resolution. Data processing in both stages of the upgrade is performed with
new, Xilinx Virtex-7 based AMC cards.Comment: 10 pages, 7 figure
Les Houches 2011: Physics at TeV Colliders New Physics Working Group Report
We present the activities of the "New Physics" working group for the "Physics
at TeV Colliders" workshop (Les Houches, France, 30 May-17 June, 2011). Our
report includes new agreements on formats for interfaces between computational
tools, new tool developments, important signatures for searches at the LHC,
recommendations for presentation of LHC search results, as well as additional
phenomenological studies.Comment: 243 pages, report of the Les Houches 2011 New Physics Group; fix
three figure
New Physics at the LHC. A Les Houches Report: Physics at TeV Colliders 2009 - New Physics Working Group
We present a collection of signatures for physics beyond the standard model
that need to be explored at the LHC. First, are presented various tools
developed to measure new particle masses in scenarios where all decays include
an unobservable particle. Second, various aspects of supersymmetric models are
discussed. Third, some signatures of models of strong electroweak symmetry are
discussed. In the fourth part, a special attention is devoted to high mass
resonances, as the ones appearing in models with warped extra dimensions.
Finally, prospects for models with a hidden sector/valley are presented. Our
report, which includes brief experimental and theoretical reviews as well as
original results, summarizes the activities of the "New Physics" working group
for the "Physics at TeV Colliders" workshop (Les Houches, France, 8-26 June,
2009).Comment: 189 page
Defining the functional role of NaV1.7 in human nociception
Loss-of-function mutations in NaV1.7 cause congenital insensitivity to pain (CIP); this voltage-gated sodium channel is therefore a key target for analgesic drug development. Utilizing a multi-modal approach, we investigated how NaV1.7 mutations lead to human pain insensitivity. Skin biopsy and microneurography revealed an absence of C-fiber nociceptors in CIP patients, reflected in a reduced cortical response to capsaicin on fMRI. Epitope tagging of endogenous NaV1.7 revealed the channel to be localized at the soma membrane, axon, axon terminals, and the nodes of Ranvier of induced pluripotent stem cell (iPSC) nociceptors. CIP patient-derived iPSC nociceptors exhibited an inability to properly respond to depolarizing stimuli, demonstrating that NaV1.7 is a key regulator of excitability. Using this iPSC nociceptor platform, we found that some NaV1.7 blockers undergoing clinical trials lack specificity. CIP, therefore, arises due to a profound loss of functional nociceptors, which is more pronounced than that reported in rodent models, or likely achievable following acute pharmacological blockade
L1 track finding for a time multiplexed trigger
At the HL-LHC, proton bunches will cross each other every 25. ns, producing an average of 140 pp-collisions per bunch crossing. To operate in such an environment, the CMS experiment will need a L1 hardware trigger able to identify interesting events within a latency of 12.5. μs. The future L1 trigger will make use also of data coming from the silicon tracker to control the trigger rate. The architecture that will be used in future to process tracker data is still under discussion. One interesting proposal makes use of the Time Multiplexed Trigger concept, already implemented in the CMS calorimeter trigger for the Phase I trigger upgrade. The proposed track finding algorithm is based on the Hough Transform method. The algorithm has been tested using simulated pp-collision data. Results show a very good tracking efficiency. The algorithm will be demonstrated in hardware in the coming months using the MP7, which is a μTCA board with a powerful FPGA capable of handling data rates approaching 1. Tb/s.This project has received funding from the European Union׳s Seventh Framework Programme for research, technological development and demonstration under grant agreement no. 317446
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