Harvesting BAT-GUANO with NITRATES (Non-Imaging Transient Reconstruction And TEmporal Search): Detecting and localizing the faintest GRBs with a likelihood framework

The detection of the gravitational wave counterpart GRB 170817A, underluminous compared to the cosmological GRB population by a factor of 10,000, motivates significant effort in detecting and localizing a dim, nearby, and slightly off-axis population of short GRBs. Swift/BAT is the most sensitive GRB detector in operation, and the only one that regularly localizes GRBs to arcminute precision, critical to rapid followup studies. However, the utility of BAT in targeted sub-threshold searches had been historically curtailed by the unavailability of the necessary raw data for analysis. The new availability of time-tagged event (TTE) data from the GUANO system (arXiv:2005.01751), motivates renewed focus on developing sensitive targeted search analysis techniques to maximally exploit these data. While computationally cheap, we show that the typical coded-mask deconvolution imaging is limited in its sensitivity due to several factors. We formalize a maximum likelihood framework for the analysis of BAT data wherein signals are forward modelled through the full instrument response, and -- coupled with the development of new response models -- demonstrate its superior sensitivity to typical imaging via archival comparisons, injection campaigns, and, after implementing as a targeted search, a large number of low-latency GRB discoveries and confirmed arcminute localizations to date. We also demonstrate independent localization of some out-of-FOV GRBs for the first time. NITRATES's increased sensitivity boosts the discovery rate of GRB 170817A-like events in BAT by a factor of at least $3-4$x, along with enabling joint analyses and searches with other GRB, GW, neutrino, and FRB instruments. We provide public access to the response functions and search pipeline code.Comment: Submitted to AAS Journals. 46 pages, 34 figures. Comments and feedback are welcome. The codebase and instrument responses can be found at https://github.com/Swift-BAT/NITRATE

Dynamics of Non-renormalizable Electroweak Symmetry Breaking

We compute the complete one-loop finite temperature effective potential for electroweak symmetry breaking in the Standard Model with a Higgs potential supplemented by higher dimensional operators as generated for instance in composite Higgs and Little Higgs models. We detail the resolution of several issues that arise, such as the cancellation of infrared divergences at higher order and imaginary contributions to the potential. We follow the dynamics of the phase transition, including the nucleation of bubbles and the effects of supercooling. We characterize the region of parameter space consistent with a strong first-order phase transition which may be relevant to electroweak baryogenesis. Finally, we investigate the prospects of present and future gravity wave detectors to see the effects of a strong first-order electroweak phase transition.Comment: 33 pages, 8 figure

Association of Cortisol and the Metabolic Syndrome in Korean Men and Women

Obesity and the metabolic syndrome are closely related and have become increasingly prevalent in Korea. The cardiovascular disease (CVD) risk factors comprising the metabolic syndrome have previously been associated with increased hypothalamic-pituitary-adrenal axis (HPAA) activity, but the associations have not been extensively examined in non-Caucasian populations. The aim of the present study was to investigate the relationships between cortisol, adiposity and the metabolic syndrome in a Korean population. A total of 1,881 adults participated in the study between January 2001 and February 2008. Sociodemographic data were assessed by questionnaires. Body composition, clinic blood pressures as well as metabolic variables including glucose, insulin, and lipid profile were assessed and analyzed in relation to cortisol levels. Mean age of the participants was 58.7 ± 10.8 yr. Higher levels of cortisol was associated with elevated blood pressure, fasting glucose and total cholesterol in men, and between cortisol and systolic blood pressure, fasting glucose and total cholesterol in women. There was an increased risk for the metabolic syndrome associated with higher cortisol levels in both men (P < 0.001) and women (P = 0.040) adjusting for age and body mass index. Higher cortisol levels are associated with several CVD risk factors and the metabolic syndrome, independent of overall of adiposity level, in Korean men and women

Top quark forward-backward asymmetry in R-parity violating supersymmetry

The interaction of bottom squark-mediated top quark pair production, occurring in the R-parity violating minimal supersymmetric standard model (MSSM), is proposed as an explanation of the anomalously large $t\bar{t}$ forward-backward asymmetry (FBA) observed at the Tevatron. We find that this model can give a good fit to top quark data, both the inclusive and invariant mass-dependent asymmetries, while remaining consistent (at the 2-$\sigma$ level) with the total and differential production cross-sections. The scenario is challenged by strong constraints from atomic parity violation (APV), but we point out an extra diagram for the effective down quark-Z vertex, involving the same coupling constant as required for the FBA, which tends to weaken the APV constraint, and which can nullify it for reasonable values of the top squark masses and mixing angle. Large contributions to flavor-changing neutral currents can be avoided if only the third generation of sparticles is light.Comment: 24 pages, 7 figures. v3: included LHC top production cross section data; model still consistent at 2 sigma leve

Comparing results of X-ray diffraction, \ub5-Raman spectroscopy and neutron diffraction when identifying chemical phases in seized nuclear material, during a comparative nuclear forensics exercise

This work presents the results for identification of chemical phases obtained by several laboratories as a part of an international nuclear forensic round-robin exercise. In this work powder X-ray diffraction (p-XRD) is regarded as the reference technique. Neutron diffraction produced a superior high-angle diffraction pattern relative to p-XRD. Requiring only small amounts of sample, \ub5-Raman spectroscopy was used for the first time in this context as a potentially complementary technique to p-XRD. The chemical phases were identified as pure UO 2 in two materials, and as a mixture of UO 2 , U 3 O 8 and an intermediate species U 3 O 7 in the third material

Supplementation of diet with krill oil protects against experimental rheumatoid arthritis

<p>Abstract</p> <p>Background</p> <p>Although the efficacy of standard fish oil has been the subject of research in arthritis, the effect of krill oil in this disease has yet to be investigated. The objective of the present study was to evaluate a standardised preparation of krill oil and fish oil in an animal model for arthritis.</p> <p>Methods</p> <p>Collagen-induced arthritis susceptible DBA/1 mice were provided <it>ad libitum </it>access to a control diet or diets supplemented with either krill oil or fish oil throughout the study. There were 14 mice in each of the 3 treatment groups. The level of EPA + DHA was 0.44 g/100 g in the krill oil diet and 0.47 g/100 g in the fish oil diet. Severity of arthritis was determined using a clinical scoring system. Arthritis joints were analysed by histopathology and graded. Serum samples were obtained at the end of the study and the levels of IL-1α, IL-1β, IL-7, IL-10, IL-12p70, IL-13, IL-15, IL-17 and TGF-β were determined by a Luminex™ assay system.</p> <p>Results</p> <p>Consumption of krill oil and supplemented diet significantly reduced the arthritis scores and hind paw swelling when compared to a control diet not supplemented with EPA and DHA. However, the arthritis score during the late phase of the study was only significantly reduced after krill oil administration. Furthermore, mice fed the krill oil diet demonstrated lower infiltration of inflammatory cells into the joint and synovial layer hyperplasia, when compared to control. Inclusion of fish oil and krill oil in the diets led to a significant reduction in hyperplasia and total histology score. Krill oil did not modulate the levels of serum cytokines whereas consumption of fish oil increased the levels of IL-1α and IL-13.</p> <p>Conclusions</p> <p>The study suggests that krill oil may be a useful intervention strategy against the clinical and histopathological signs of inflammatory arthritis.</p