English
Related papers

Related papers: Modelling hybrid Beta Cephei/SPB pulsations: Gamma…

200 papers

We analyse photometry of $\sim$2000 Galactic Cepheids available in the OGLE Collection of Variable Stars. We analyse both Galactic disk and Galactic bulge fields; stars classified both as single- and multi-periodic. Our goal was to search…

Solar and Stellar Astrophysics · Physics 2021-07-07 R. S. Rathour , R. Smolec , H. Netzel

We have made velocity observations of the star alpha Cen B from two sites, allowing us to identify 37 oscillation modes with l=0-3. Fitting to these modes gives the large and small frequency separations as a function of frequency. The mode…

We report first-principles calculations on the normal and superconducting state of CaBe(x)Si(2-x) (x=1), in the framework of density functional theory for superconductors (SCDFT). CaBeSi is isostructural and isoelectronic to MgB2 and this…

Superconductivity · Physics 2013-05-29 C. Bersier , A. Floris , A. Sanna , G. Profeta , A. Continenza , E. K. U. Gross , S. Massidda

Seismic modeling of the Slowly Pulsating B-type star HD182255 yields strong constraints on the radial orders of the two dominant modes. For these frequencies, we derive also the empirical values of the complex nonadiabatic parameter $f$.…

Solar and Stellar Astrophysics · Physics 2015-06-12 Przemysław Walczak , Wojciech Szewczuk , Jadwiga Daszyńska-Daszkiewicz

We use RHESSI high-resolution imaging and spectroscopy observations from ~6 to 100 keV to determine the statistical relationships between measured parameters (temperature, emission measure, etc.) of hot, thermal plasma in 37 intense (GOES…

Solar and Stellar Astrophysics · Physics 2014-06-25 Amir Caspi , Säm Krucker , R. P. Lin

The light curves of 252 B-star candidates in the Kepler data base are analyzed in a similar fashion to that done by Balona et al. (2011) to further characterize B star variability, increase the sample of variable B stars for future study,…

Solar and Stellar Astrophysics · Physics 2012-03-19 Bernard J. McNamara , Jason Jackiewicz , Jean McKeever

Following the discovery of blue large-amplitude pulsators (BLAPs) by the OGLE survey, additional hot, high-amplitude pulsating stars have been discovered by the Zwicky Transient Facility. It has been proposed that all of these objects are…

Solar and Stellar Astrophysics · Physics 2019-12-11 Conor M. Byrne , C. Simon Jeffery

Our study is motivated by the prospect of several metastable states in the Sb$ ^{+} $, Au$ ^{+} $, and Hg$ ^{2+} $ ions being used as possible candidates for optical clocks. We calculate several atomic properties relevant to the development…

Atomic Physics · Physics 2023-06-21 Saleh O. Allehabi , V. A. Dzuba , V. V. Flambaum

The spectral response and directional scattering of semiconductor-oxide core-shell spherical microparticles embedded in an insulating medium at low volume fraction are computed using Mie Theory and Multiscale Modelling methods. The surface…

Mesoscale and Nanoscale Physics · Physics 2019-01-23 Kevin Conley , Vaibhav Thakore , Tapio Ala-Nissila

We report a multisite photometric campaign for the Beta Cep stars V2052 Oph and V986 Oph. 670 hours of high-quality differential photoelectric Stromgren, Johnson and Geneva time-series photometry were obtained with eight telescopes on five…

Context. The origin of blazar variability, seen from radio up to gamma rays, is still a heavily debated matter and broadband flares offer a unique testbed towards a better understanding of these extreme objects. Such an energetic outburst…

High Energy Astrophysical Phenomena · Physics 2016-05-11 V. Karamanavis , L. Fuhrmann , E. Angelakis , I. Nestoras , I. Myserlis , T. P. Krichbaum , J. A. Zensus , H. Ungerechts , A. Sievers , M. A. Gurwell

By performing constant-pressure variable-cell ab initio molecular dynamics simulations we find a quadrupolar orthorhombic structure, of $Pca2_1$ symmetry, for the broken symmetry phase (phase II) of solid H2 at T=0 and P =110 - 150 GPa. We…

Materials Science · Physics 2009-10-30 Jorge Kohanoff , Sandro Scandolo , Guido L. Chiarotti , Erio Tosatti

Using a sample of 14 million $\psip$ events collected with the BESII detector, branching fractions or upper limits on the branching fractions of $\psip$ decays into $\gamma\ppb$, $\gamma 2(\pip\pim)$, $\gamma \kskp$, $\gamma…

High Energy Physics - Experiment · Physics 2008-03-27 BES Collaboration , M. Ablikim

A multisite photometric campaign for the Beta Cephei and eclipsing variable 16 Lacertae is reported. 749 h of high-quality differential photoelectric Stromgren, Johnson and Geneva time-series photometry were obtained with ten telescopes…

We analyze optical and ultraviolet observations of the symbiotic binary AG Pegasi acquired during 1992-97. The bolometric luminosity of the hot component declined by a factor of 2-3 from 1980-1985 to 1997. Since 1992, the effective…

Astrophysics · Physics 2009-11-06 Scott J. Kenyon , Daniel Proga , Charles D. Keyes

The OGLE project led to discovery of earlier unknown forms of multiperiodic pulsation in Cepheids. Often, the observed periods may be explained in terms of simultaneous excitation of two or rarely three radial modes. However, a secondary…

Solar and Stellar Astrophysics · Physics 2012-12-06 W. A. Dziembowski

We present multi-epoch observations from the Submillimeter Array (SMA) for a sample of 171 bright blazars, 43 of which were detected by Fermi during the first three months of observations. We explore the correlation between their gamma-ray…

High Energy Astrophysical Phenomena · Physics 2010-01-07 Allison L. Strom , Aneta Siemiginowska , Mark A. Gurwell , Brandon C. Kelly

By use of the high-resolution spectral data and the broadband imaging obtained with the Goode Solar Telescope at the Big Bear Solar Observatory on 2013 June 6, the spectra of three typical photospheric bright points (PBPs) have been…

Solar and Stellar Astrophysics · Physics 2020-07-21 Q. Hao , C. Fang , M. D. Ding , Z. Li , W. Cao

We present the results of spectral analysis of 42 simultaneous broad-band Ginga--OSSE and RXTE--OSSE observations of Cyg X-1 carried out in 1991 and 1996--1999. The hardest spectra in our sample in the energy range from 3 to \~1000 keV can…

The spectra of only a few pulsars are known in the low-energy gamma-ray region around 1 Mev. We searched for point sources of gamma-radiation in the 0.3-1 and 1-8 Mev bandpasses at the location of known radio and X-ray pulsars. Single…

High Energy Astrophysical Phenomena · Physics 2011-04-21 Joseph F. Dolan