ATLAS Forward Detectors and Physics

In this communication I describe the ATLAS forward physics program and the detectors, LUCID, ZDC and ALFA that have been designed to meet this experimental challenge. In addition to their primary role in the determination of ATLAS luminosity these detectors - in conjunction with the main ATLAS detector - will be used to study soft QCD and diffractive physics in the initial low luminosity phase of ATLAS running. Finally, I will briefly describe the ATLAS Forward Proton (AFP) project that currently represents the future of the ATLAS forward physics program.Comment: 4 pages, Proceedings for Lake Louise Winter Institute 201

Search for nonpointing photons in the diphoton and ETmiss final state in root s=7 TeV proton-proton collisions using the ATLAS detector

A search has been performed for photons originating in the decay of a neutral long-lived particle, exploiting the capabilities of the ATLAS electromagnetic calorimeter to make precise measurements of the flight direction of photons, as well as the calorimeter's excellent time resolution. The search has been made in the diphoton plus missing transverse energy final state, using the full data sample of 4.8 fb⁻¹ of 7 TeV proton-proton collisions collected in 2011 with the ATLAS detector at the LHC. No excess is observed above the background expected from Standard Model processes. The results are used to set exclusion limits in the context of gauge mediated supersymmetry breaking models, with the lightest neutralino being the next-to-lightest supersymmetric particle and decaying with a lifetime in excess of 0.25 ns into a photon and a gravitino.G. Aad ... P. Jackson ... N. Soni ... M. J. White ... et al. (ATLAS Collaboration

Giant Goos-H\"anchen shift in Scattering: the role of interfering Localized Plasmon modes

The longitudinal and the transverse beam shifts, namely, the Goos-H\"anchen (GH) and the Spin-Hall (SH) shifts are usually observed at planar interfaces. It has recently been shown that the transverse SH shift may also arise due to scattering of plane waves. Here, we show that analogous in-plane (longitudinal) shift also exist in scattering of plane waves from micro/nano systems. We study both the GH and the SH shifts in plasmonic metal nanoparticles/ nanostructures and dielectric micro-particles employing a unified framework that utilizes the transverse components of the Poynting vector of the scattered wave. The results demonstrate that interference of neighboring resonance modes in plasmonic nanostructures (e.g., electric dipolar and quadrupolar modes in metal spheres) leads to giant enhancement of GH shift in scattering from such systems. We also unravel interesting correlations between these shifts with the polarimetry parameters, diattenuation and retardance.Comment: 4 pages, 3 figure

QQˉQ\bar Q (Q∈{b,c}Q\in \{b, c\}) spectroscopy using Cornell potential

The mass spectra and decay properties of heavy quarkonia are computed in nonrelativistic quark-antiquark Cornell potential model. We have employed the numerical solution of Schr\"odinger equation to obtain their mass spectra using only four parameters namely quark mass ($m_c$, $m_b$) and confinement strength ($A_{c\bar c}$, $A_{b\bar b}$). The spin hyperfine, spin-orbit and tensor components of the one gluon exchange interaction are computed perturbatively to determine the mass spectra of excited $S$, $P$, $D$ and $F$ states. Digamma, digluon and dilepton decays of these mesons are computed using the model parameters and numerical wave functions. The predicted spectroscopy and decay properties for quarkonia are found to be consistent with available experimental observations and results from other theoretical models. We also compute mass spectra and life time of the $B_c$ meson without additional parameters. The computed electromagnetic transition widths of heavy quarkonia and $B_c$ mesons are in tune with available experimental data and other theoretical approaches

Evaluation of alloxan on induction of diabetes in albino rats

Background: Alloxan-induced diabetes model is used as a “study tool” to elucidate the pathophysiology of the disease and much more as a “search engine” for antidiabetic compounds with better therapeutic characteristics. It was the first agent used in the category of chemically induced diabetes to create a model of insulin dependent diabetes mellitus. Other chemicals being streptozocin, dexamethasone, insulin antibodies-induced diabetes.Methods: Albino rats were divided into four groups with ten rats in each group. Alloxan monohydrate 2%, solution which was dissolved in 0.9% of sodium chloride (normal saline) as a diluent and given intraperitoneally to rats and blood glucose estimation made by using glucometer. Total 40 albino rats were taken and divided into 4 groups. 10 rats receiving normal saline were grouped as Group A, 10 rats received alloxan at a dose of 150 mg/kg as Group B, 10 rats received alloxan at a dose of 160 mg/kg as Group C and 10 rats received alloxan at a dose of 170 mg/kg as Group D.Results: Highest rate of mortality and alopecia were noted in group D receiving alloxan at a dose of 170 mg/kg whereas highest percentage of fluctuation in fasting blood glucose range was seen in group C receiving alloxan at a dose of 160 mg/kg.Conclusions: Such unpredictable response shows that alloxan is not ideal drug for induction of diabetes in experimental animal. Mortality, fasting blood glucose returning to non-diabetic range and alopecia are the chief drawbacks