Validation of upgrade of the Geant4 Simulation Toolkit to Model the Responses from TOP and ARICH Detectors

Belle II is the next generation B-Factory experiment at the world\u27s highest luminosity accelerator the SuperKEKB collider, which is designed to collect 50 times more data than the previous generation experiments. A hallmark feature of B-Factory experiments is to use novel characteristics of Cherenkov detectors for identification of the flavor of charged particles passing through the detector. The TOP and the ARICH detectors can identify charged pions and kaons with high precision. The response to the passage of high energetic particles in the detector is modeled with the Geant4 simulation toolkit. Here we compare the performances of these two detectors of particle identification at the Belle II experiment following an upgrade of the list of physical processes simulated by the Geant4 toolkit. The new list is found to give consistent results when compared to the default list while improving the CPU requirement of the Geant4 toolkit by as much as 25%.https://ir.library.louisville.edu/uars/1022/thumbnail.jp

Adsorption hysteresis and capillary condensation in disordered porous solids: a density functional study

We present a theoretical study of capillary condensation of fluids adsorbed in mesoporous disordered media. Combining mean-field density functional theory with a coarse-grained description in terms of a lattice-gas model allows us to investigate both the out-of-equilibrium (hysteresis) and the equilibrium behavior. We show that the main features of capillary condensation in disordered solids result from the appearance of a complex free-energy landscape with a large number of metastable states. We detail the numerical procedures for finding these states, and the presence or absence of transitions in the thermodynamic limit is determined by careful finite-size studies.Comment: 30 pages, 18 figures. To appear in J. Phys.: Condens. Matte

Radius constraints from high-speed photometry of 20 low-mass white dwarf binaries

We carry out high-speed photometry on 20 of the shortest-period, detached white dwarf binaries known and discover systems with eclipses, ellipsoidal variations (due to tidal deformations of the visible white dwarf), and Doppler beaming. All of the binaries contain low-mass white dwarfs with orbital periods less than 4 hr. Our observations identify the first eight tidally distorted white dwarfs, four of which are reported for the first time here, which we use to put empirical constraints on the mass-radius relationship for extremely low-mass (<0.30 Msun) white dwarfs. We also detect Doppler beaming in several of these binaries, which confirms the high-amplitude radial-velocity variability. All of these systems are strong sources of gravitational radiation, and long-term monitoring of those that display ellipsoidal variations can be used to detect spin-up of the tidal bulge due to orbital decay.Comment: 14 pages, 5 figures, accepted for publication in The Astrophysical Journa

EUV emission lines and diagnostics observed with Hinode/EIS

Quiet Sun and active region spectra from the Hinode/EIS instrument are presented, and the strongest lines from different temperature regions discussed. A list of emission lines recommended to be included in EIS observation studies is presented based on analysis of blending and diagnostic potential using the CHIANTI atomic database. In addition we identify the most useful density diagnostics from the ions covered by EIS.Comment: 14 pages, 3 figures, submitted to PASJ Hinode first results issu

Overlapping functions of the cell adhesion molecules Nr-CAM and L1 in cerebellar granule cell development

The structurally related cell adhesion molecules L1 and Nr-CAM have overlapping expression patterns in cerebellar granule cells. Here we analyzed their involvement in granule cell development using mutant mice. Nr-CAM–deficient cerebellar granule cells failed to extend neurites in vitro on contactin, a known ligand for Nr-CAM expressed in the cerebellum, confirming that these mice are functionally null for Nr-CAM. In vivo, Nr-CAM–null cerebella did not exhibit obvious histological defects, although a mild size reduction of several lobes was observed, most notably lobes IV and V in the vermis. Mice deficient for both L1 and Nr-CAM exhibited severe cerebellar folial defects and a reduction in the thickness of the inner granule cell layer. Additionally, anti-L1 antibodies specifically disrupted survival and maintenance of Nr-CAM–deficient granule cells in cerebellar cultures treated with antibodies. The combined results indicate that Nr-CAM and L1 play a role in cerebellar granule cell development, and suggest that closely related molecules in the L1 family have overlapping functions

The Swift-UVOT ultraviolet and visible grism calibration

We present the calibration of the Swift UVOT grisms, of which there are two, providing low-resolution field spectroscopy in the ultraviolet and optical bands respectively. The UV grism covers the range 1700-5000 Angstrom with a spectral resolution of 75 at 2600 Angstrom for source magnitudes of u=10-16 mag, while the visible grism covers the range 2850-6600 Angstrom with a spectral resolution of 100 at 4000 Angstrom for source magnitudes of b=12-17 mag. This calibration extends over all detector positions, for all modes used during operations. The wavelength accuracy (1-sigma) is 9 Angstrom in the UV grism clocked mode, 17 Angstrom in the UV grism nominal mode and 22 Angstrom in the visible grism. The range below 2740 Angstrom in the UV grism and 5200 Angstrom in the visible grism never suffers from overlapping by higher spectral orders. The flux calibration of the grisms includes a correction we developed for coincidence loss in the detector. The error in the coincidence loss correction is less than 20%. The position of the spectrum on the detector only affects the effective area (sensitivity) by a few percent in the nominal modes, but varies substantially in the clocked modes. The error in the effective area is from 9% in the UV grism clocked mode to 15% in the visible grism clocked mode .Comment: 27 pages, 31 figures; MNRAS accepted 23 February 201

Numerical Confirmation of Late-time t^{1/2} Growth in Three-dimensional Phase Ordering

Results for the late-time regime of phase ordering in three dimensions are reported, based on numerical integration of the time-dependent Ginzburg-Landau equation with nonconserved order parameter at zero temperature. For very large systems ($700^3$) at late times, $t \ge 150,$ the characteristic length grows as a power law, $R(t) \sim t^n$, with the measured $n$ in agreement with the theoretically expected result $n=1/2$ to within statistical errors. In this time regime $R(t)$ is found to be in excellent agreement with the analytical result of Ohta, Jasnow, and Kawasaki [Phys. Rev. Lett. {\bf 49}, 1223 (1982)]. At early times, good agreement is found between the simulations and the linearized theory with corrections due to the lattice anisotropy.Comment: Substantially revised and enlarged, submitted to PR

The mass ratio distribution of B-type visual binaries in the Sco OB2 association

The sample of 115 B-type stars in Sco OB2 association is examined for existence of visual companions with ADONIS near-infrared adaptive optics system and coronograph in J and K bands. Practically all components in the separation range 0.3"-6" (45-900 A.U.) were detected, with magnitudes down to K=16. The K and J-K photometry of primaries and differential photometry and astrometry of 96 secondaries are presented. Ten secondaries are new physical components, as inferred from photometric and statistical criteria, while remaining are faint background stars. After small correction for detection incompleteness and conversion of fluxes into masses, an unbiased distribution of the components mass ratio q is derived. The power law f(q)\propto q^{-0.5} fits well the observations, whereas a q^{-1.8} distribution which corresponds to random pairing of stars is rejected. The companion star fraction is 0.20 +- 0.04 per decade of separation, comparable to the highest measured binary fraction among low-mass PMS stars and ~1.6 times higher than the binary fraction of low-mass dwarfs in solar neighborhood and open clusters in the same separation range.Comment: 12 pages, submitted to Astronomy & Astrophysic

Paper II: Calibration of the Swift ultraviolet/optical telescope

The Ultraviolet/Optical Telescope (UVOT) is one of three instruments onboard the Swift observatory. The photometric calibration has been published, and this paper follows up with details on other aspects of the calibration including a measurement of the point spread function with an assessment of the orbital variation and the effect on photometry. A correction for large scale variations in sensitivity over the field of view is described, as well as a model of the coincidence loss which is used to assess the coincidence correction in extended regions. We have provided a correction for the detector distortion and measured the resulting internal astrometric accuracy of the UVOT, also giving the absolute accuracy with respect to the International Celestial Reference System. We have compiled statistics on the background count rates, and discuss the sources of the background, including instrumental scattered light. In each case we describe any impact on UVOT measurements, whether any correction is applied in the standard pipeline data processing or whether further steps are recommended.Comment: Accepted for publication in MNRAS. 15 pages, 21 figures, 4 table

Accounting students' expectations and transition experiences of supervised work experience

Political and economic discourses position employability as a responsibility of higher education, which utilise mechanisms such as supervised work experience (SWE) to embed employability into the undergraduate curriculum. However, sparse investigation of students' contextualised experiences of SWE results in little being known about the mechanisms through which students derive employability benefits from SWE. The aim of this study is to examine the impact of students' expectation and conception of workplace learning on their transition into SWE. Analysis of accounting students' experiences reveal two broad conceptions of workplace learning, the differing impacts of which on transition experience are explored using existing learning transfer perspectives. Students displaying the more common 'technical' conception construct SWE as an opportunity to develop technical, knowledge-based expertise and abilities that prioritize product-based or cognitive learning transfer. Students with an 'experiential' conception were found to construct SWE primarily as an experience through which the development of personal skills and abilities beyond technical expertise are prioritized using process-based or socio-cultural learning transfer. Further data analysis suggests that these two learning transfer approaches have differing impacts on students' employability development which may indicate a need for universities to consider how to develop appropriate student expectations of and approaches to SWE and meaningful support for students' SWE transition