This is the "TeV4LHC" report of the "Physics Landscapes" Working Group,
focused on facilitating the start-up of physics explorations at the LHC by
using the experience gained at the Tevatron. We ...present experimental and
theoretical results that can be employed to probe various scenarios for physics
beyond the Standard Model.
This is the "TeV4LHC" report of the "Physics Landscapes" Working Group, focused on facilitating the start-up of physics explorations at the LHC by using the experience gained at the Tevatron. We ...present experimental and theoretical results that can be employed to probe various scenarios for physics beyond the Standard Model.
Multi-point wave observations on Cluster spacecraft are used to infer the dispersion relation of electromagnetic ion cyclotron (EMIC) waves. In this study we use a phase differencing method and ...observations from STAFF and WHISPER during a well-studied event of 30 March 2002. The phase differencing method requires the knowledge of the direction of the wave vector, which was obtained using minimum variance analysis. Wave vector amplitudes were calculated for a number of frequencies to infer the dispersion relation experimentally. The obtained dispersion relation is largely consistent with the cold plasma dispersion relation. The presented method allows inferring the dispersion relation experimentally. It can be also used in the future to analyse the hot plasma dispersion relation of waves near the local gyrofrequency that can occur under high plasma beta conditions.
This study presents a fusion of data‐driven and physics‐driven methodologies of energetic electron flux forecasting in the outer radiation belt. Data‐driven NARMAX (Nonlinear AutoRegressive Moving ...Averages with eXogenous inputs) model predictions for geosynchronous orbit fluxes have been used as an outer boundary condition to drive the physics‐based Versatile Electron Radiation Belt (VERB) code, to simulate energetic electron fluxes in the outer radiation belt environment. The coupled system has been tested for three extended time periods totalling several weeks of observations. The time periods involved periods of quiet, moderate, and strong geomagnetic activity and captured a range of dynamics typical of the radiation belts. The model has successfully simulated energetic electron fluxes for various magnetospheric conditions. Physical mechanisms that may be responsible for the discrepancies between the model results and observations are discussed.
Key Points
Physics‐and‐data coupled code developedTested for several weeks of representative stormsReproduces observations, discrepancies discussed
A new high precision measurement of the J/ψ- and ψ′-meson masses has been performed at the VEPP-4M collider using the KEDR detector. The resonant depolarization method has been employed for the ...absolute calibration of the beam energy. The following mass values have been obtained: MJ/ψ=3096.917±0.010±0.007 MeV,Mψ′=3686.111±0.025±0.009 MeV. The relative measurement accuracy has reached 4×10−6 for J/ψ and 7×10−6 for ψ′, approximately 3 times better than in the previous precise experiments.
In the Compact Muon Solenoid (CMS) experiment, muon detection in the forward direction is accomplished by cathode strip chambers (CSC). These detectors identify muons, provide a fast muon trigger, ...and give a precise measurement of the muon trajectory. There are 468 six-plane CSCs in the system. The efficiency of finding muon trigger primitives (muon track segments) was studied using 36 CMS CSCs and cosmic ray muons during the Magnet Test and Cosmic Challenge (MTCC) exercise conducted by the CMS experiment in 2006. In contrast to earlier studies that used muon beams to illuminate a very small chamber area (
<
0.01
m
2
), results presented in this paper were obtained by many installed CSCs operating in situ over an area of
≈
23
m
2
as a part of the CMS experiment. The efficiency of finding two-dimensional trigger primitives within six-layer chambers was found to be
99.93
±
0.03
%
. These segments, found by the CSC electronics within 800
ns after the passing of a muon through the chambers, are the input information for the Level-1 muon trigger and, also, are a necessary condition for chambers to be read out by the Data Acquisition System.
Reverse transcriptase from rat brain Ivanov, V A; Pakhotin, P I; Bobkova, N V ...
Doklady Akademii nauk,
1992, Letnik:
323, Številka:
1
Journal Article
This Report summarises the activities of the "SM and Higgs" working group for
the Workshop "Physics at TeV Colliders", Les Houches, France, 2-20 May, 2005.
On the one hand, we performed a variety of ...experimental and theoretical studies
on standard candles (such as W, Z, and ttbar production), treating them either
as proper signals of known physics, or as backgrounds to unknown physics; we
also addressed issues relevant to those non-perturbative or semi-perturbative
ingredients, such as Parton Density Functions and Underlying Events, whose
understanding will be crucial for a proper simulation of the actual events
taking place in the detectors. On the other hand, several channels for the
production of the Higgs, or involving the Higgs, have been considered in some
detail. The report is structured into four main parts. The first one deals with
Standard Model physics, except the Higgs. A variety of arguments are treated
here, from full simulation of processes constituting a background to Higgs
production, to studies of uncertainties due to PDFs and to extrapolations of
models for underlying events, from small-$x$ issues to electroweak corrections
which may play a role in vector boson physics. The second part of the report
treats Higgs physics from the point of view of the signal. In the third part,
reviews are presented on the current status of multi-leg, next-to-leading order
and of next-to-next-to-leading order QCD computations. Finally, the fourth part
deals with the use of Monte Carlos for simulation of LHC physics.