4,497 research outputs found
Higgs Boson Discovery and Properties
We outline issues examined and progress made by the Light Higgs Snowmass 1996
working group regarding discovering Higgs bosons and measuring their detailed
properties. We focused primarily on what could be learned at LEP2, the Tevatron
(after upgrade), the LHC, a next linear \epem collider and a \mupmum
collider.Comment: 47 pages, full postscript file also available via anonymous ftp at
ftp://ucdhep.ucdavis.edu/gunion/summary_snowmass96.ps To appear in
``Proceedings of the 1996 DPF/DPB Summer Study on New Directions for High
Energy Physics''. Minor revisions of references and wording have been made in
a few place
Renal Stone Formation in Patients with Inflammatory Bowel Disease
Kidney stones are more common in patients with inflammatory bowel disease (IBD) than in the general population. The main lithogenetic risk factors were evaluated in patients affected by Crohn\u27s disease and ulcerative colitis. Our results show the presence of several factors, besides hyperoxaluria, in patients with IBD although their behaviour appears different in Crohn\u27s disease and ulcerative colitis at pre- and post-operative stages. Before surgery in patients with Crohn\u27s disease we found a decreased citrate (p \u3c 0.001) and magnesium (p \u3c 0.005) excretion together with a low urinary volume (p \u3c 0.001) and pH (p \u3c 0.005). After surgery patients with Crohn\u27s disease showed a further reduction of magnesium and citrate. Patients with ulcerative colitis before surgery showed a reduced citrate excretion (p \u3c 0.05) and a more acidic pH (p \u3c 0.05) than healthy subjects. Surgical treatment of proctocolectomy with ileal pouch-anal anastomosis seems to increase the risk of stone formation; in fact, after surgery we observed a relevant decrease of urinary volume (p \u3c 0.001), pH (p \u3c 0.0001) and urinary excretion of citrate (p \u3c0.0001) as well as magnesium (p \u3c 0.005). Patients with IBD seem to be at greater risk of stone formation than patients with idiopathic calcium lithiasis; in fact, they show a lower excretion of citrate (p \u3c 0.001) and magnesium (p \u3c 0.001) together with a low urinary pH (p \u3c 0.001) and volume (p \u3c 0.001). Urinary volume reduction is probably one of the major risk factors together with the decrease of small molecular weight inhibitors that is a constant finding in all patients with IBD
Infliximab in the treatment of Crohn's disease
The recent introduction of infliximab, a chimeric monoclonal antibody against tumor necrosis factor-alpha, has greatly modified the treatment of Crohn's disease (CD). Data from the literature show encouraging results after intravenous infusion both for closure of intestinal or perianal fistulas and for induction and maintenance of remission in patients with moderate to severe intestinal disease unresponsive to other treatments. However, some contraindications such as fibrostenosing CD and sepsis have been identified. In addition, the data on long-term outcomes and safety is still limited. Our initial experience showed that in selected cases local injection of infliximab is effective in the treatment of complex perianal disease offering the possibility of using such treatment even in small bowel obstructing disease with minimal systemic effects. This paper analyzes the state of the use of both intravenous and local injection of infliximab in patients with CD
Energy Linearity and Resolution of the ATLAS Electromagnetic Barrel Calorimeter in an Electron Test-Beam
A module of the ATLAS electromagnetic barrel liquid argon calorimeter was
exposed to the CERN electron test-beam at the H8 beam line upgraded for
precision momentum measurement. The available energies of the electron beam
ranged from 10 to 245 GeV. The electron beam impinged at one point
corresponding to a pseudo-rapidity of eta=0.687 and an azimuthal angle of
phi=0.28 in the ATLAS coordinate system. A detailed study of several effects
biasing the electron energy measurement allowed an energy reconstruction
procedure to be developed that ensures a good linearity and a good resolution.
Use is made of detailed Monte Carlo simulations based on Geant which describe
the longitudinal and transverse shower profiles as well as the energy
distributions. For electron energies between 15 GeV and 180 GeV the deviation
of the measured incident electron energy over the beam energy is within 0.1%.
The systematic uncertainty of the measurement is about 0.1% at low energies and
negligible at high energies. The energy resolution is found to be about 10%
sqrt(E) for the sampling term and about 0.2% for the local constant term
Dimensionless Coupling of Bulk Scalars at the LHC
We identify the lowest-dimension interaction which is possible between
Standard Model brane fields and bulk scalars in 6 dimensions. The
lowest-dimension interaction is unique and involves a trilinear coupling
between the Standard Model Higgs and the bulk scalar. Because this interaction
has a dimensionless coupling, it depends only logarithmically on ultraviolet
mass scales and heavy physics need not decouple from it. We compute its
influence on Higgs physics at ATLAS and identify how large a coupling can be
detected at the LHC. Besides providing a potentially interesting signal in
Higgs searches, such couplings provide a major observational constraint on 6D
large-extra-dimensional models with scalars in the bulk.Comment: 20 page
User Requirements and User Strategy in the AWARE Project
Abstract AWARE (A tool for monitoring and forecasting Available WAter REsource in mountain environment) is a Project in the VI Framework Programme of European Community. It started in July 2005 and aims at offering methods and tools to monitor and forecast the water resource from Alpine snowmelt by hydrologic models using input data derived from both in situ observations and Earth Observations (EO). In order to reach its objectives, AWARE needs strength collaboration with users. To this purpose activities to raise users' interests, to meet users' expectations and to spread Project achievements are planned. This paper describes the strategy used to collect user requirements within AWARE and illustrates some results of the user requirements analysis
Position resolution and particle identification with the ATLAS EM calorimeter
In the years between 2000 and 2002 several pre-series and series modules of
the ATLAS EM barrel and end-cap calorimeter were exposed to electron, photon
and pion beams. The performance of the calorimeter with respect to its finely
segmented first sampling has been studied. The polar angle resolution has been
found to be in the range 50-60 mrad/sqrt(E (GeV)). The neutral pion rejection
has been measured to be about 3.5 for 90% photon selection efficiency at pT=50
GeV/c. Electron-pion separation studies have indicated that a pion fake rate of
(0.07-0.5)% can be achieved while maintaining 90% electron identification
efficiency for energies up to 40 GeV.Comment: 32 pages, 22 figures, to be published in NIM
Hadron Energy Reconstruction for the ATLAS Calorimetry in the Framework of the Non-parametrical Method
This paper discusses hadron energy reconstruction for the ATLAS barrel
prototype combined calorimeter (consisting of a lead-liquid argon
electromagnetic part and an iron-scintillator hadronic part) in the framework
of the non-parametrical method. The non-parametrical method utilizes only the
known ratios and the electron calibration constants and does not require
the determination of any parameters by a minimization technique. Thus, this
technique lends itself to an easy use in a first level trigger. The
reconstructed mean values of the hadron energies are within of the
true values and the fractional energy resolution is . The value of the ratio
obtained for the electromagnetic compartment of the combined calorimeter is
and agrees with the prediction that for this
electromagnetic calorimeter. Results of a study of the longitudinal hadronic
shower development are also presented. The data have been taken in the H8 beam
line of the CERN SPS using pions of energies from 10 to 300 GeV.Comment: 33 pages, 13 figures, Will be published in NIM
Measurement of the cross-section and charge asymmetry of bosons produced in proton-proton collisions at TeV with the ATLAS detector
This paper presents measurements of the and cross-sections and the associated charge asymmetry as a
function of the absolute pseudorapidity of the decay muon. The data were
collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with
the ATLAS experiment at the LHC and correspond to a total integrated luminosity
of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements
varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the
1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured
with an uncertainty between 0.002 and 0.003. The results are compared with
predictions based on next-to-next-to-leading-order calculations with various
parton distribution functions and have the sensitivity to discriminate between
them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables,
submitted to EPJC. All figures including auxiliary figures are available at
https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13
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