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The proposed magnetized Iron CALorimeter detector (ICAL) to be built in the India-based Neutrino Observatory (INO) laboratory aims to study atmospheric neutrinos and its properties such as precision measurements of oscillation parameters and the neutrino mass hierarchy. High energy charged current (CC) interactions of atmospheric neutrinos with the rock surrounding the detector produce so-called "rock muons" along with hadrons. While the hadron component of these events are absorbed in the rock itself, the rock muons traverse the rock and are detected in the detector. These rock muon events can be distinguished from cosmic muons only in the upward direction and can provide an independent measurement of the oscillation parameters. A simulation study of these events at the ICAL detector shows that, although reduced in significance compared to muons produced in direct CC neutrino interactions with the detector, these events are indeed sensitive to the oscillation parameters, achieving a possible 1 σ precision of 10% and 27% in determining Δ m 32 2 and sin 2 θ 23 , respectively. Hence a combination of the standard atmospheric neutrino analysis which is the main goal of ICAL, with these rock muon events, will improve the precision reach of ICAL for these parameters. [ABSTRACT FROM AUTHOR]

It is known that the infrared (IR) divergences accruing from pure fermion–photon interactions at finite temperature cancel to all orders in perturbation theory. The corresponding infrared finiteness of scalar thermal QED has also been established recently. Here, we study the IR behaviour, at finite temperature, of theories where charged scalars and fermions interact with neutrals that could potentially be dark matter candidates. Such thermal field theories contain both linear and sub-leading logarithmic divergences. We prove that the theory is IR-finite to all orders in perturbation, with the divergences cancelling order by order between virtual and real photon corrections, when both absorption and emission of photons from and into the heat bath are taken into account. The calculation follows closely the technique used by Grammer and Yennie for zero temperature field theory. The result is generic and applicable to a variety of models, independent of the specific form of the neutral-fermion–scalar interaction vertex. [ABSTRACT FROM AUTHOR]

A combined analysis of both (LEP, SLD) and (RHIC-PHENIX and LHC-ALICE) hadroproduction processes are done for the first time for the vector meson nonet at the next-to-leading order (NLO) using a model with broken SU(3) symmetry. The transverse momentum () and rapidity () dependence of the differential cross-section for and mesons of the data are also discussed. The input universal quark (valence and singlet) fragmentation functions at a starting scale of , after evolution, have values that are consistent with the earlier analysis for at NLO. However, the universal gluon fragmentation function is now well determined from this study with significantly smaller error bars, as the hadroproduction cross-section is particularly sensitive to the gluon fragmentation since it occurs at the same order as the quark fragmentation, in contrast to the hadroproduction process. Additional parameters involved in describing the strangeness and sea suppression and octet-singlet mixing are found to be close to the earlier analysis; in addition, a new relation between the gluon and sea suppression in and hadroproduction has been observed. [ABSTRACT FROM AUTHOR]

We determine the sensitivity to neutrino oscillation parameters from a study of atmospheric neutrinos in a magnetised detector such as the ICAL at the proposed India-based Neutrino Observatory. In such a detector, which can separately count νμ and νμ-induced events, the relatively smaller (about 5%) uncertainties on the neutrino-antineutrino flux ratios translate to a constraint in the χ² analysis that results in a significant improvement in the precision with which neutrino oscillation parameters such as sin2 θ23 can be determined. Such an effect is unique to all magnetisable detectors and constitutes a great advantage in determining neutrino oscillation parameters using such detectors. Such a study has been performed for the first time here. Along with an increase in the kinematic range compared to earlier analyses, this results in sensitivities to oscillation parameters in the 2-3 sector that are comparable to or better than those from accelerator experiments where the fluxes are significantly higher. For example, the 1σ precisions on sin² θ23 and |Δm²32(31)| achievable for 500 kton year exposure of ICAL are ~9 and ~2.5%, respectively, for both normal and inverted hierarchies. The mass hierarchy sensitivity achievable with this combinationwhen the true hierarchy is normal (inverted) for the same exposure is πχ² ≈ 8.5 (πχ² ≈ 9.5). [ABSTRACT FROM AUTHOR]

A detailed study of fragmentation of vector mesons at the next-to-leading order (NLO) in QCD is given for e+e– scattering. A model with broken SU(3) symmetry using three input fragmentation functions α(x,Q2), β(x,Q2) and γ(x,Q2) and a strangeness suppression parameter λ describes all the light quark fragmentation functions for the entire vector meson octet. At a starting low energy scale of Q02 = 1.5 (GeV)2 for three light quarks (u, d, s) along with initial parametrization, the fragmentation functions are evolved through DGLAP evolution equations at NLO and the cross-section is calculated. The heavy quarks contribution are added in appropriate thresholds during evolution. The results obtained are fitted at the momentum scale of √s = 91.2 GeV for LEP and SLD data. Good-quality fits are obtained for ⍴, K*, ⍵ and 𝜙 mesons, implying the consistency and efficiency of this model. Strangeness suppression in this model is understood both in terms of ratios of quark fragmentation functions alone as well as in terms of observables; the latter yield a suppression through the K*/⍴ multiplicity ratio of about 0.23 while the x dependence of this suppression is also parametrized through the cross-section ratios. [ABSTRACT FROM AUTHOR]

The estrogenic monomer bisphenol-A (BPA) is an endocrine-disrupting chemical used in the production of epoxy resins, plastic food and beverage containers, leading to ubiquitous human exposure. Environmentally relevant doses of BPA have profound effects on mice endocrine pancreas. It increases pancreatic insulin content and favors postprandial hyperinsulinemia and insulin resistance in male mice. Skeletal muscle plays a crucial role in maintaining systemic glucose metabolism. In the present study, we investigated the possible effects of BPA on insulin-signaling molecules and glucose oxidation in skeletal muscle of male rat. Adult male Wistar albino rats were divided into three groups. Group I: control (vehicle treated) and groups II and III were administered with BPA orally (20 and 200 mg/kg bw/day, respectively). Although there was no change in the levels of insulin receptor (IR), Akt (protein kinase B) and glucose transporter-4 (GLUT4) messenger RNA, BPA significantly decreased the IR, Akt and GLUT4 protein levels (both plasma membrane and cytosolic fraction) of the gastrocnemius muscle. There was an increase in serum insulin and decrease in serum testosterone levels but fasting blood glucose level remained unaltered. In conclusion, BPA has adverse effects on phosphorylation of Akt, GLUT4 translocation and 14C-glucose oxidation. [ABSTRACT FROM AUTHOR]

Inclusive hadro-production in e+e- annihilation processes is examined to study the fragmentation process. A broken SU(3) model is used to determine the quark and gluon fragmentation functions of octet vector mesons, ρ and K*, in a simple way with an SU(3) breaking parameter λ. These are expressed in terms of just two light quark fragmentation functions, V(x, Q2) and γ(x, Q2) and the gluon fragmentation function Dg(x, Q2). These functions are parametrized at the low input scale of , evolved through LO DGLAP evolution including charm and bottom flavor at appropriate thresholds, and fitted by comparison with data at the Z-pole. The model is extended with the introduction of a few additional parameters to include a study of singlet-octet mixing and hence ω and ϕ fragmentation. The model gives good fits to the available data for x ≳0.01, where x is the scaled energy of the hadron. The model is then applied successfully to ω, ϕ production in pp collisions at the relativistic heavy ion collider, RHIC, these data form an important baseline for the study of Quark Gluon Plasma in heavy nucleus collisions at RHIC, and also in future at the LHC. [ABSTRACT FROM AUTHOR]

Abstract: We follow up on the analysis of Mecozzi and Bellini (arXiv:1110.1253v1) where they showed, in principle, the possibility of superluminal propagation of neutrinos, as indicated by the recent OPERA result. We refine the analysis by introducing wave packets for the superposition of energy eigenstates and discuss the implications of their results with realistic values for the mixing and mass parameters in a full three neutrino mixing scenario. Our analysis shows the possibility of superluminal propagation of neutrino flavour in a very narrow range of neutrino parameter space. Simultaneously this reduces the number of observable events drastically. Therefore, the OPERA result cannot be explained in this frame-work. [Copyright &y& Elsevier]

We briefly review neutrino properties, with emphasis on neutrino oscillations. We then present a status report on the proposed India-based Neutrino Observatory (INO). We focus on the physics studies possible with an iron calorimeter detector (ICAL) and the logistics of constructing this detector at INO. Such a detector would study atmospheric neutrinos in the first phase with the possibility of acting as a far-end detector of a future neutrino factory or beta beam. This talk was given at the Cosmology and Particle Astrophysics (CosPA) conference at Taipei, in Nov 2006. [ABSTRACT FROM AUTHOR]

Models explaining dark matter typically include interactions with charged scalar and fermion fields. The infra-red (IR) finiteness of thermal field theories of charged fermions (fermionic QED) has been proven to all orders in perturbation theory. Here we reexamine the IR behaviour of charged scalar theories at finite temperature. Using the method of Grammer and Yennie, we identify and factorise the infra-red divergences to all orders in perturbation theory. The inclusion of IR finite pieces arising from the 4-point interaction terms of scalars with photon fields is key to the exponentiation. We use this in a companion paper to prove the IR finiteness of the corresponding thermal theory which is of relevance in dark matter calculations. [ABSTRACT FROM AUTHOR]

An obituary for Rahul Basu, an expert on the theory of quantum chromodynamics (QCD) and strong interactions is presented.

The magnetized iron calorimeter (ICAL) detector, proposed to be built in the India-based neutrino observatory (INO) laboratory, aims to study atmospheric neutrino oscillations. A simulations study of response of muons to the ICAL detector is presented in the form of momentum reconstruction, angle resolution and reconstruction, and charge identification efficiency (CID). [ABSTRACT FROM AUTHOR]

We present the reach of the proposed INO-ICAL in measuring the atmospheric-neutrino-oscillation parameters θ 23 and Δ m 32 2 using full event-by-event reconstruction for the first time. We also study the fluctuations arising from the low event statistics and their effect on the precision measurements and mass-hierarchy analysis for a 5-year exposure of the 50 kton ICAL detector. We find a mean resolution of Δ χ 2 ≈ 2.9 , which rules out the wrong mass hierarchy of the neutrinos with a significance of approximately 1.7 σ . These results on mass-hierarchy are similar to those presented in earlier studies that approximated the performance of the ICAL detector. [ABSTRACT FROM AUTHOR]

We describe an undergraduate-level experiment that demonstrates the role of probabilistic observations in physics. A capacitor and a dc voltmeter are used to randomly sample an ac voltage. The resulting probability distribution is analyzed to extract information about the source. Different characteristic probability distributions arising from various ac waveforms are calculated and experimentally measured. We show how limited information about the waveform can be extracted from the voltage probability distribution, which is used to reconstruct the waveform for the special case of a sinusoidal waveform. The results are also compared with a simulated data sample. The experiment can be used as a pedagogical tool to teach probabilistic measurements and their manipulations. [ABSTRACT FROM AUTHOR]

In this article, the authors criticize the comment made by editors of the journal regarding the publication of scientific facts and figures. They mention that editors should have cross-checked information with expert engineers and geologists to verify the statements. They also mentions that no geotechnical study has been carried out by the editors.