S. K. Dhawan

Learn More
We present the final report from a series of precision measurements of the muon anomalous magnetic moment, a µ = (g − 2)/2. The details of the experimental method, apparatus, data taking, and analysis are summarized. Data obtained at Brookhaven National Laboratory, using nearly equal samples of positive and negative muons, were used to deduce a µ (Expt) =(More)
The muon (g − 2) value has played an important role in constraining physics beyond the standard model. We propose to develop an improved Muon (g −2) experiment at J-PARC with the design goal of an improvement of a factor of 5 to 10 over E821 at Brookhaven, (relative uncertainty 0.1 to 0.06 parts per million). At this proposed level of precision a robust(More)
The photoproduction reaction γp → µ + µ − p has been studied in ep interactions using the ZEUS detector at HERA. The data sample corresponds to an integrated luminosity of 43.2 pb −1. The Υ meson has been observed in photoproduction for the first time. The sum of the products of the elastic Υ(1S), Υ(2S), Υ(3S) photoproduction cross sections with their(More)
Exclusive production of 0 and J== mesons in e + p collisions has been studied with the ZEUS detector in the kinematic range 0:25 < Q 2 < 50 GeV 2 , 20 < W < 167 GeV for the 0 data and 2 < Q 2 < 40 GeV 2 , 50 < W < 150 GeV for the J== data. Cross sections for exclusive 0 and J== production have been measured as a function of Q 2 , W and t. The spin-density(More)
The beauty production cross section for deep inelastic scattering events with at least one hard jet in the Breit frame together with a muon has been measured, for photon virtualities Q 2 > 2 GeV 2 , with the ZEUS detector at HERA using integrated luminosity of 72 pb −1. The total visible cross section is σ bb (ep → e jet µ X) = 40.9 ± 5.7 (stat.) +6.0 −4.4(More)
Differential inclusive jet cross sections in neutral current deep inelastic ep scattering have been measured with the ZEUS detector using an integrated luminosity of 38.7 pb −1. The jets have been identified using the k T cluster algorithm in the longitudinally invariant inclusive mode in the laboratory frame; they have been selected with jet transverse(More)
Next-to-leading-order QCD analyses of the ZEUS data on deep inelastic scattering together with fixed-target data have been performed, from which the gluon and quark densities of the proton and the value of the strong coupling constant, α s (M Z), were extracted. The study includes a full treatment of the experimental systematic uncertainties including(More)
Elastic and proton–dissociative photoproduction of ρ 0 , φ and J/ψ vector mesons (γp → V p, γp → V N , respectively) have been measured in e + p interactions at HERA up to −t = 3 GeV 2 , where t is the four-momentum transfer squared at the photon–vector meson vertex. The analysis is based on a data sample in which photoproduction reactions were tagged by(More)
BACKGROUND Abdominal surgery involving bowel manipulation commonly results in inflammation of the bowel wall, which leads to impaired intestinal motility and postoperative ileus (POI). Mast cells have shown to play a key role in the pathogenesis of POI in mouse models and human studies. We studied whether mast cells contribute to the pathogenesis of POI by(More)
A dedicated B physics experiment is proposed for the Fermilab Tevatron p-¯ p Col-lider. The goal is to study the full range of physics associated with 10 10 produced B ¯ B pairs per year. This corresponds to a run of 10 7 sec at an average luminosity of 10 31 cm −2 sec −1 , with a σ B ¯ B ∼ 45 μbarns and a ratio of 1 B ¯ B pair/1000 inelastic events. Since(More)