15 research outputs found
RPC Performance study using 2012 and 2015 data
Resistive Plate Chambers are the dedicated trigger muon detector for the Compact Muon Solenoid experiment at the Large Hadron Collider at CERN. HV50 is one of the parameter under study to eventually spot any aging effect. The comparative study is done for Barrel and Endcap region particularly, and as a whole too confirming the excellent behavior of RPC detector and fulfillment of requirement as per decided before the upgrade
Comparing efficacy of Rifaximin plus Lactulose vs. Lactulose alone in treating Hepatic Encephalopathy
Background: Hepatic Encephalopathy is a syndrome observed in patients with liver cirrhosis. Various treatment modalities are in use for treatment of Porto Systemic Encephalopathy (PSE). Our study aimed to compare the efficacy of Rifaximin plus Lactulose vs.Lactulose alone in treating Hepatic Encephalopathy in local population.
Materials & Methods: The study was conducted at a tertiary care hospital recruiting decompensated chronic liver disease(DCLD) patients with PSE. Using simple random sampling, patients were divided in two groups (A & B). Patients in group A received Lactulose plus Rifaximin while group B received Lactulose alone. Efficacy of treatment was assessed as return of the conscious level to pre-encephalopathy state as per clinical examination within 1 week after start of the treatment.
Results: A total of 124 patients were included in the study with each group (A & B) containing 62 patients. Frequency and percentage of efficacy among group A (Rifaximin plus Lactulose) verses group B (Lactulose alone) in treating Hepatic encephalopathy was 45 (72.6%) and 32 (51.6%) respectively.
Conclusion: The study concluded that there is a significant difference in proportions of patients showing complete recovery from Hepatic encephalopathy treated with Lactulose plus Rifaximin as compared to Lactulose alone
Comparing efficacy of Rifaximin plus Lactulose vs. Lactulose alone in treating Hepatic Encephalopathy
Background: Hepatic Encephalopathy is a syndrome observed in patients with liver cirrhosis. Various treatment modalities are in use for treatment of Porto Systemic Encephalopathy (PSE). Our study aimed to compare the efficacy of Rifaximin plus Lactulose vs.Lactulose alone in treating Hepatic Encephalopathy in local population.
Materials & Methods: The study was conducted at a tertiary care hospital recruiting decompensated chronic liver disease(DCLD) patients with PSE. Using simple random sampling, patients were divided in two groups (A & B). Patients in group A received Lactulose plus Rifaximin while group B received Lactulose alone. Efficacy of treatment was assessed as return of the conscious level to pre-encephalopathy state as per clinical examination within 1 week after start of the treatment.
Results: A total of 124 patients were included in the study with each group (A & B) containing 62 patients. Frequency and percentage of efficacy among group A (Rifaximin plus Lactulose) verses group B (Lactulose alone) in treating Hepatic encephalopathy was 45 (72.6%) and 32 (51.6%) respectively.
Conclusion: The study concluded that there is a significant difference in proportions of patients showing complete recovery from Hepatic encephalopathy treated with Lactulose plus Rifaximin as compared to Lactulose alone.</jats:p
Comparison of inclusive and photon-tagged jet suppression in 5.02 TeV Pb+Pb collisions with ATLAS
Parton energy loss in the quark–gluon plasma (QGP) is studied with a measurement of photon-tagged jet production in 1.7 nb<sup>−1</sup> of Pb+Pb data and 260 pb<sup>−1</sup> of pp data, both at sNN=5.02 TeV, with the ATLAS detector. The process pp →γ+jet+X and its analogue in Pb+Pb collisions is measured in events containing an isolated photon with transverse momentum (pT) above 50 GeV and reported as a function of jet pT. This selection results in a sample of jets with a steeply falling pT distribution that are mostly initiated by the showering of quarks. The pp and Pb+Pb measurements are used to report the nuclear modification factor, RAA, and the fractional energy loss, Sloss, for photon-tagged jets. In addition, the results are compared with the analogous ones for inclusive jets, which have a significantly smaller quark-initiated fraction. The RAA and Sloss values are found to be significantly different between those for photon-tagged jets and inclusive jets, demonstrating that energy loss in the QGP is sensitive to the colour-charge of the initiating parton. The results are also compared with a variety of theoretical models of colour-charge-dependent energy loss
Search for non-resonant production of semi-visible jets using Run 2 data in ATLAS
Semi-visible jets, with a significant contribution to the event's missing transverse momentum, can arise in strongly interacting dark sectors. This results in an event topology where one of the jets can be aligned with the direction of the missing transverse momentum. The first search for semi-visible jets produced via a t-channel mediator exchange is presented. The analysis uses proton-proton collisions with an integrated luminosity of 139 fb<sup>−1</sup> and a centre-of-mass energy of 13 TeV, collected with the ATLAS detector during the Run 2 of the LHC. No excess over Standard Model predictions is observed. Assuming a coupling strength of unity between the mediator, a Standard Model quark and a dark quark, mediator masses up to 2.7 TeV are excluded at the 95% confidence level. Upper limits on the coupling strength are also derived
Measurements of longitudinal flow decorrelations in and Xe+Xe collisions with the ATLAS detector
Measurements of longitudinal flow decorrelations in 13 TeV and 5.44 TeV Xe+Xe collisions with the ATLAS detector are presented. The measurements are performed using the two-particle correlation method, combining charged-particle tracks within |\eta| < 2.5 with either calorimeter energy clusters or towers within 4.0<|\eta|<4.9. A template-based subtraction procedure is used to remove non-flow effects in both the and the Xe+Xe analyses. The dependence of the longitudinal flow decorrelations on the pseudorapidity separation between the particles is characterized via the slope parameter for the elliptic () and triangular () harmonic moments. The results are reported as a function of charged-particle multiplicity for the and Xe+Xe collision systems. Comparing the data to a color string-based model of the initial geometry indicates that in and peripheral Xe+Xe collisions, sub-nucleonic structure and fluctuations in longitudinal energy deposition are needed to describe the data
A detailed map of Higgs boson interactions by the ATLAS experiment ten years after the discovery
The standard model of particle physics describes the known fundamental particles and forces that make up our Universe, with the exception of gravity. One of the central features of the standard model is a field that permeates all of space and interacts with fundamental particles. The quantum excitation of this field, known as the Higgs field, manifests itself as the Higgs boson, the only fundamental particle with no spin. In 2012, a particle with properties consistent with the Higgs boson of the standard model was observed by the ATLAS and CMS experiments at the Large Hadron Collider at CERN. Since then, more than 30 times as many Higgs bosons have been recorded by the ATLAS experiment, enabling much more precise measurements and new tests of the theory. Here, on the basis of this larger dataset, we combine an unprecedented number of production and decay processes of the Higgs boson to scrutinize its interactions with elementary particles. Interactions with gluons, photons, and W and Z bosons—the carriers of the strong, electromagnetic and weak forces—are studied in detail. Interactions with three third-generation matter particles (bottom (b) and top (t) quarks, and tau leptons (τ)) are well measured and indications of interactions with a second-generation particle (muons, μ) are emerging. These tests reveal that the Higgs boson discovered ten years ago is remarkably consistent with the predictions of the theory and provide stringent constraints on many models of new phenomena beyond the standard model.The Standard Model of particle physics describes the known fundamental particles and forces that make up our universe, with the exception of gravity. One of the central features of the Standard Model is a field that permeates all of space and interacts with fundamental particles. The quantum excitation of this field, known as Higgs field, manifests itself as the Higgs boson, the only fundamental particle with no spin. In 2012, a particle with properties consistent with the Higgs boson of the Standard Model was observed by the ATLAS and CMS experiments at the Large Hadron Collider at CERN. Since then, more than 30 times as many Higgs bosons have been recorded by the ATLAS experiment, allowing much more precise measurements and new tests of the theory. Here, on the basis of this larger dataset, we combine an unprecedented number of production and decay processes of the Higgs boson to scrutinize its interactions with elementary particles. Interactions with gluons, photons, and and bosons -- the carriers of the strong, electromagnetic, and weak forces -- are studied in detail. Interactions with three third-generation matter particles (bottom () and top () quarks, and tau leptons ()) are well measured and indications of interactions with a second-generation particle (muons, ) are emerging. These tests reveal that the Higgs boson discovered ten years ago is remarkably consistent with the predictions of the theory and provide stringent constraints on many models of new phenomena beyond the Standard Model
Evidence for the Higgs Boson Decay to a <math display="inline"><mi>Z</mi></math> Boson and a Photon at the LHC
The first evidence for the Higgs boson decay to a Z boson and a photon is presented, with a statistical significance of 3.4 standard deviations. The result is derived from a combined analysis of the searches performed by the ATLAS and CMS Collaborations with proton-proton collision datasets collected at the CERN Large Hadron Collider (LHC) from 2015 to 2018. These correspond to integrated luminosities of around 140 fb-1 for each experiment, at a center-of-mass energy of 13 TeV. The measured signal yield is 2.2±0.7 times the standard model prediction, and agrees with the theoretical expectation within 1.9 standard deviations
A precise determination of the strong-coupling constant from the recoil of bosons with the ATLAS experiment at TeV
The coupling constant of the strong force is determined from the transverse-momentum distribution of bosons produced in 8 TeV proton-proton collisions at the LHC and recorded by the ATLAS experiment. The -boson cross sections are measured in the full phase space of the decay leptons using 15.3 million electron and muon pairs, in a dataset collected in 2012 and corresponding to an integrated luminosity of 20.2 fb. The analysis is based on predictions evaluated at third order in perturbative QCD, supplemented by the resummation of logarithmically enhanced contributions in the low transverse-momentum region of the lepton pairs. The determined value of the strong coupling at the reference scale corresponding to the -boson mass is . This is the most precise experimental determination of achieved so far
