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Evolutionary status of W Vir pulsating variables: Stellar evolution calculations for population II stars with initial composition $Y_0=0.25$, $Z_0=10^{-3}$ and the initial stellar mass $M_0 = 0.82M_\odot$ were carried out from the main sequence to the white dwarf stage. Twelve AGB and post--AGB evolutionary sequences w...
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COSMIC RAYS FROM ACCRETING ISOLATED NEUTRON STARS: Interstellar matter that is accreted onto isolated magnetic neutron stars in the Galaxy ($\sim 10^9$ by number) is accelerated and reflected back by MHD shocks, which envelope the stars. The integrated power in the Galaxy $L_{cr,ns}$ is $ \sgreat 10^{40} {\rm erg \ s^{...
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Systematic differences in simple stellar population model results: Application to the M31 globular-like cluster system: Simple stellar population (SSP) synthesis models are useful tools for studying the nature of unresolved star clusters in external galaxies. However, the plethora of currently available SSP models gi...
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Dark Matter Halos in Galaxies and Globular Cluster Populations: We combine a new, comprehensive database for globular cluster populations in all types of galaxies with a new calibration of galaxy halo masses based entirely on weak lensing. Correlating these two sets of data, we find that the mass ratio $\eta \equiv M_{...
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Ultraviolet C II and Si III Transit Spectroscopy and Modeling of the Evaporating Atmosphere of GJ436b: Hydrogen gas evaporating from the atmosphere of the hot-Neptune GJ436b absorbs over 50% of the stellar Ly$\alpha$ emission during transit. Given the planet's atmospheric composition and energy-limited escape rate, t...
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How Spatially Resolved Polarimetry Informs Black Hole Accretion Flow Models: The Event Horizon Telescope (EHT) Collaboration has successfully produced images of two supermassive black holes, enabling novel tests of black holes and their accretion flows on horizon scales. The EHT has so far published total intensity a...
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Modeling the Mass Distribution in Spiral Galaxies: We use deep r-band photometry and Halpha rotation curves for a sample of 290 late-type spirals to model their mass distribution within the optical radius. We examine luminosity profile decompositions into bulge and disk carefully and confirm that bulge light is best mo...
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Yet another UFO in the X-ray spectrum of a high-z lensed QSO: Ultra-fast outflows (UFO) appear to be common in local active galactic nuclei (AGN) and may be powerful enough ($\dot{E}_{kin}$$\geq$1\% of L$_{bol}$) to effectively quench the star formation in their host galaxies. To test feedback models based on AGN outfl...
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MUCHFUSS - Massive Unseen Companions to Hot Faint Underluminous Stars from SDSS: The project Massive Unseen Companions to Hot Faint Underluminous Stars from SDSS (MUCHFUSS) aims at finding hot subdwarf stars with massive compact companions (white dwarfs with masses $M>1.0 {\rm M_{\odot}}$, neutron stars or black hole...
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Electron Acceleration at Rippled Low-Mach-number Shocks in High-beta Collisionless Cosmic Plasmas: Using large-scale fully-kinetic two-dimensional particle-in-cell simulations, we investigate the effects of shock rippling on electron acceleration at low-Mach-number shocks propagating in high-$\beta$ plasmas, in appli...
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Analysis of the Data from Compton X-ray Polarimeters which Measure the Azimuthal and Polar Scattering Angles: X-ray polarimetry has the potential to make key-contributions to our understanding of galactic compact objects like binary black hole systems and neutron stars, and extragalactic objects like active galactic ...
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Periodograms for Multiband Astronomical Time Series: This paper introduces the multiband periodogram, a general extension of the well-known Lomb-Scargle approach for detecting periodic signals in time-domain data. In addition to advantages of the Lomb-Scargle method such as treatment of non-uniform sampling and heteros...
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Galaxy Formation with BECDM: I. Turbulence and relaxation of idealised haloes: We present a theoretical analysis of some unexplored aspects of relaxed Bose-Einstein condensate dark matter (BECDM) haloes. This type of ultralight bosonic scalar field dark matter is a viable alternative to the standard cold dark matter ...
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Neutrino spectra evolution during proto-neutron star deleptonization: The neutrino-driven wind, which occurs after the onset of a core-collapse supernova explosion, has long been considered as the possible site for the synthesis of heavy r-process elements in the Universe. Only recently, it has been possible to simulat...
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Identifying hot subdwarf stars from photometric data using Gaussian mixture model and graph neural network: Hot subdwarf stars are very important for understanding stellar evolution, stellar astrophysics, and binary star systems. Identifying more such stars can help us better understand their statistical distribution...
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VLA Detection of RRLs from the radio nucleus of NGC 253 : Ionization by a weak AGN, an obscured SSC or a compact SNR ?: We have imaged the H92alpha and H75alpha radio recombination line (RRL) emissions from the starburst galaxy NGC 253 with a resolution of ~4 pc. The peak of the RRL emission at both frequencies coinc...
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The Hawaii Infrared Parallax Program. I. Ultracool Binaries and the L/T Transition: We present the first results from our high-precision infrared (IR) astrometry program at the Canada-France-Hawaii Telescope. We measure parallaxes for 83 ultracool dwarfs (spectral types M6--T9) in 49 systems, with a median uncertaint...
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Quantum vacuum and accelerated expansion: A new approach to extraction of quantum vacuum energy, in the context of the accelerated expansion, is proposed, and it is shown that experimentally realistic orders of values can be derived. The idea has been implemented in the framework of the Friedmann-Lemaitre-Robertson-Wal...
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Almost All of Kepler's Multiple Planet Candidates are Planets: We present a statistical analysis that demonstrates that the overwhelming majority of Kepler candidate multiple transiting systems (multis) indeed represent true, physically-associated transiting planets. Binary stars provide the primary source of false pos...
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ROSAT PSPC and Hri Observations of the Composite Starburst/Seyfert 2 Galaxy NGC 1672: The nearby barred spiral galaxy NGC 1672 is thought to have a weak Seyfert nucleus in addition to its strong starburst activity. Observations with the PSPC and HRI instruments on board the ROSAT X-ray satellite show that three X-ray...
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The Host Galaxy of GRB 060505: Host ISM Properties: We investigate the ISM environment of GRB 060505. Using optical emission-line diagnostic ratios, we compare the ISM properties of the GRB 060505 host region with the hosts of unambiguous long- and short-duration GRBs. We show that the metallicity, ionization state, an...
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Properties of Ellipticity Correlation with Atmospheric Structure from Gemini South: Cosmic shear holds great promise for a precision independent measurement of $\Omega\rm_m$, the mass density of the universe relative to the critical density. The signal is expected to be weak, so a thorough understanding of systematic...
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Radiative Transfer Effect on Ultraviolet Pumping of the 21cm Line in the High Redshift Universe: During the epoch of reionization the 21cm signal is sensitive to the scattering rate of the ultraviolet photons, redshifting across the Lyman_alpha resonance. Here we calculate the photon scattering rate profile for a sin...
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On the Efficiency of Thermal Conduction in Galaxy Clusters: Galaxy clusters host a large reservoir of diffuse plasma with radially-varying temperature profiles. The efficiency of thermal conduction in the intracluster medium (ICM) is complicated by the existence of turbulence and magnetic fields, and has received a lot...
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Mapping the Clumpy Structures within Submillimeter Galaxies using Laser-Guide Star Adaptive Optics Spectroscopy: We present the first integral-field spectroscopic observations of high-redshift submillimeter-selected galaxies (SMGs) using Laser Guide Star Adaptive Optics (LGS-AO). We target H-alpha emission of three S...
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Searching for an Intermediate Mass Black Hole in the Blue Compact Dwarf galaxy MRK 996: The possibility is explored that accretion on an intermediate mass black hole contributes to the ionisation of the interstellar medium of the Compact Blue Dwarf galaxy MRK996. Chandra observations set tight upper limits (99.7 per ...
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Stability of planetary, single M dwarf, and binary star companions to Kepler detached eclipsing binaries and a possible five body system: In this study we identify 11 Kepler systems (KIC 5255552, 5653126, 5731312, 7670617, 7821010, 8023317, 10268809, 10296163, 11519226, 11558882 and 12356914) with a "flip-flop" effec...
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Dependence of fragmentation in self-gravitating accretion discs on small scale structure: We propose a framework for understanding the fragmentation criterion for self-gravitating discs which, in contrast to studies that emphasise the `gravoturbulent' nature of such discs, instead focuses on the properties of their q...
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Improved Weak Lensing Photometric Redshift Calibration via StratLearn and Hierarchical Modeling: Discrepancies between cosmological parameter estimates from cosmic shear surveys and from recent Planck cosmic microwave background measurements challenge the ability of the highly successful $\Lambda$CDM model to describ...
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Topology of the Galaxy Distribution in the Hubble Deep Fields: We have studied topology of the distribution of the high redshift galaxies identified in the Hubble Deep Field (HDF) North and South. The two-dimensional genus is measured from the projected distributions of the HDF galaxies at angular scales from $3.8''$ t...
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Numerical study of Cosmic Ray Diffusion in MHD turbulence: We study diffusion of Cosmic Rays (CRs) in turbulent magnetic fields using test particle simulations. Electromagnetic fields are produced in direct numerical MHD simulations of turbulence and used as an input for particle tracing, particle feedback on turbulenc...
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The Galactic Plane Observed by XMM-Newton: In A0-1 we proposed an ambitious long-term survey of selected regions of our Galaxy (the XGPS survey) using the EPIC CCD cameras on XMM-Newton. The first phase of the programme, which aims to survey a strip of the Galactic Plane in the Scutum region, is currently underway. Her...
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Possible Quasi-Periodic Oscillations from Unstable Accretion: 3D MHD Simulations: We investigate the photometric variability of magnetized stars, particularly neutron stars, accreting through a magnetic Rayleigh-Taylor-type instability at the disk-magnetosphere interface, and compare it with the variability during st...
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High time resolution observations of the January 2000 glitch in the Vela pulsar: Pulsars are rotating neutron stars, sweeping the emission regions from the magnetic poles across our line of sight. Isolated neutron stars lose angular momentum through dipole radiation and (possibly) particle winds, hence they slow down...
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Jupiter's equatorial quasi-quadrennial oscillation forced by internal thermal forcing: Observations have shown that there exists downward propagation of alternating westward/eastward jets in Jupiter's equatorial stratosphere, with a quasi-period between four and six years. This phenomenon is generally called the quas...
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First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Preliminary Maps and Basic Results: We present full sky microwave maps in five bands (23 to 94 GHz) from the WMAP first year sky survey. Calibration errors are <0.5% and the low systematic error level is well specified. The 2<l<900 anisotropy power ...
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The SONYC survey: Towards a complete census of brown dwarfs in star forming regions: SONYC, short for "Substellar Objects in Nearby Young Clusters", is a survey program to provide a census of the substellar population in nearby star forming regions. We have conducted deep optical and near-infrared photometry in five ...
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Evolution of the L1 halo family in the radial solar sail CRTBP: We present a detailed investigation of the dramatic changes that occur in the $\mathcal{L}_1$ halo family when radiation pressure is introduced into the Sun-Earth circular restricted three-body problem (CRTBP). This photo-gravitational CRTBP can be used to...
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Neutrinos as a diagnostic of cosmic ray Galactic/extra-galactic transition: Motivated by a recent change in viewing the onset of the extra-galactic component in the cosmic ray spectrum, we have fitted the observed data down to $10^{8.6}$ GeV and have obtained the corresponding power emissivity. This transition energy...
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Unusual Burst Emission from the New Soft Gamma Repeater SGR1627-41: In June-July,1998 the Konus-Wind burst spectrometer observed a series of bursts from the new soft gamma repeater SGR1627-41. Time histories and energy spectra of the bursts have been studied, revealing fluences and peak fluxes in the ranges of 3x10^{-7...
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On the Particle Acceleration Mechanisms in a Double Radio Relic Galaxy Cluster, Abell 1240: We present a 368 ks deep Chandra observation of Abell~1240, a binary merging galaxy cluster at a redshift of 0.195 with two Brightest Cluster Galaxies (BCGs) may have passed each other 0.3 Gyr ago. Building upon previous inves...
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Thermal structure and cooling of neutron stars with magnetized envelopes: The thermal structure of neutron stars with magnetized envelopes is studied using modern physics input. The relation between the internal (T_i) and local surface temperatures is calculated and fitted by analytic expressions for magnetic field str...
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The ALHAMBRA survey: an empirical estimation of the cosmic variance for merger fraction studies based on close pairs: Our goal is to estimate empirically, for the first time, the cosmic variance that affects merger fraction studies based on close pairs. We compute the merger fraction from photometric redshift close p...
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Signatures of a Maxwellian Component in Shock-Accelerated Electrons in GRBs: Recent particle-in-cell simulations suggest that a large fraction of the energy dissipated in a relativistic shock is deposited into a Maxwellian distribution of electrons that is connected to the high-energy power-law tail. Here, we explore...
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Nonlinear cascades in two-dimensional turbulent magnetoconvection: The dynamics of spectral transport in two-dimensional turbulent convection of electrically conducting fluids is studied by means of direct numerical simulations (DNS) in the frame of the magnetohydrodynamic (MHD) Boussinesq approximation. The system per...
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The Greater Taurus-Auriga Ecosystem I: There Is A Distributed Older Population: The Taurus-Auriga association and its associated molecular cloud are a benchmark population for studies of star and planet formation. The census of Taurus-Auriga has been assembled over seven decades and has inherited the biases, incomple...
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A Swift Fix II: Physical Parameters of Type I Superluminous Supernovae: In November 2020, the Swift team announced a major update to the calibration of the UltraViolet and Optical Telescope (UVOT) data to correct for the gradual loss of sensitivity over time. Beginning in roughly 2015, the correction affected observati...
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The Evolution and Star Formation History of M33: We construct a parameterized model to explore the main properties of the star formation history of M33. We assume that the disk originates and grows by the primordial gas infall and adopt the simple form of gas accretion rate with one free parameter, the infall time-scal...
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HAT-P-47b AND HAT-P-48b: Two Low Density Sub-Saturn-Mass Transiting Planets on the Edge of the Period--Mass Desert: We report the discovery of two new transiting extrasolar planets orbiting moderately bright (V = 10.7 and 12.2 mag) F stars (masses of 1.39 Msun and 1.10 Msun, respectively). The planets have periods of...
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X-ray Reverberation Observational Modelling in Active Galactic Nuclei: X-ray reverberation in Active Galactic Nuclei, believed to be the result of the reprocessing of coronal photons by the underlying accretion disc, has allowed us to probe the properties of the inner-most regions of the accretion flow and the central ...
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A Viscous Heating Mechanism for the Hot Plasma in the Galactic Center Region: In addition to lines originating in a soft phase at ~0.8 keV and to cold molecular clouds, the X-ray spectra from the Galactic center region also exhibit properties similar to those of a diffuse, thin, very hot plasma at 8 keV on a scale of...
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Cosmological parameters from the comparison of peculiar velocities with predictions from the 2M++ density field: Peculiar velocity measurements are the only tool available in the low-redshift Universe for mapping the large-scale distribution of matter and can thus be used to constrain cosmology. Using redshifts from ...
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Multi-band optical variability of the Blazar S5 0716+714 in outburst state during 2014-2015: We analyzed the multi-band optical behaviour of the BL Lacertae object, S5 0716+714, during its outburst state from 2014 November - 2015 March. We took data on 23 nights at three observatories, one in India and two in Bulgari...
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Red-Sequence Galaxies at High Redshift by the COMBO-17+4 Survey: We investigate the evolution of the galaxy population since redshift 2 with a focus on the colour bimodality and mass density of the red sequence. We obtain precise and reliable photometric redshifts up to z=2 by supplementing the optical survey COMBO-17 ...
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The DRAO Synthesis Telescope: The DRAO Synthesis Telescope (ST) is a forefront telescope for imaging large-scale neutral hydrogen and polarized radio continuum emission at arcminute resolution. Equipped for observations at 1420 and 408 MHz, the ST completed the Canadian Galactic Plane Survey, providing pioneering measu...
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Solar Activity and Space Weather: After providing an overview of solar activity as measured by the sunspot number (SSN) and space weather events during solar cycles (SCs) 21-24, we focus on the weak solar activity in SC 24. The weak solar activity reduces the number of energetic eruptions from the Sun and hence the num...
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Strong stellar-driven outflows shape the evolution of galaxies at cosmic dawn: We study galaxy mass assembly and cosmic star formation rate (SFR) at high-redshift (z$\gt$4), by comparing data from multiwavelength surveys with predictions from the GAlaxy Evolution and Assembly (GAEA) model. GAEA implements a stellar f...
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Calibrating Galaxy Redshifts Using Absorption by the Surrounding Intergalactic Medium: Rest-frame UV spectral lines of star-forming galaxies are systematically offset from the galaxies' systemic redshifts, probably because of large-scale outflows. We calibrate galaxy redshifts measured from rest-frame UV lines by uti...
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Stimulated Raman scattering of water maser lines in astrophysical plasmas: Radiative transfer equations are derived and solved for the stimulated Raman scattering of water maser lines in the astrophysical plasmas with electron density of about 10^6 - 10^7 cm-3. In stimulated Raman scattering, the energy of water mase...
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Tomography of the environment of the COSMOS/AzTEC-3 submillimeter galaxy at z=5.3 revealed by Lyalpha and MUSE observations: We study the members of the protocluster around AzTEC3 submillimeter galaxy at z=5.3. We analyzed the data from the MUSE instrument in an area of 1.4x1.4 arcmin^2 around AzTEC3 and derived info...
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Accretion by the Secondary in Eta Carinae During the Spectroscopic Event: I. Flow Parameters: We examine the influence of the gravity of the companion (the secondary) to the massive primary star Eta Carinae on the winds blown by the primary and the secondary. The two winds collide with each other after passing throug...
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Wetter Stratospheres on High Obliquity Planets: We investigate how obliquity affects stratospheric humidity using a 3D general circulation model and find the stratosphere under high obliquity could be over 3 orders of magnitude moister than under the low obliquity equivalent, even with the same global annual mean surfa...
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Diagnostic of the temperature and differential emission measure (DEM) based on Hinode/XRT data: We discuss here various methodologies and an optimal strategy of the temperature and emission measure diagnostics based on Hinode X-Ray Telescope data. As an example of our results we present determination of the temperatu...
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Special point on the mass radius diagram of hybrid stars: An analytical study that explains the existence of a very small region on the mass radius diagram of hybrid stars where all of the lines representing the sequences of models with different constant values of the bag constant B intersect is presented. This circum...
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Common envelope events with low-mass giants: understanding the energy budget: Common envelope events are important interactions between two binary stars that lead to the formation of close binary systems. We present here a systematic three-dimensional study in which we model common envelope events with low-mass giant...
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Detecting and interpreting statistical lensing by absorbers: We propose a method for detecting gravitational magnification of distant sources, like quasars, due to absorber systems detected in their spectra. We first motivate the use of metal absorption lines rather than Lyman-alpha lines, then we show how to relate th...
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Uncertainties in the Galactic dark matter distribution: an update: We present here a quantitative, accurate estimate of the impact of uncertainties of astrophysical nature on the determination of the dark matter distribution within our Galaxy, the Milky Way. Based on an update of a previous analysis, this work is motiv...
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A Time-Efficient, Data Driven Modelling Approach For Predicting The Geomagnetic Impact of Coronal Mass Ejections: To understand the global-scale physical processes behind coronal mass ejection (CME)-driven geomagnetic storms and predict their intensity as a space weather forecasting measure, we develop an interplanet...
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Generation of large-scale magnetic fields due to fluctuating $α$ in shearing systems: We explore the growth of large-scale magnetic fields in a shear flow, due to helicity fluctuations with a finite correlation time, through a study of the Kraichnan-Moffatt model of zero-mean stochastic fluctuations of the $\alpha$ p...
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A Comparison of the UV and HI Properties of the Extended UV (XUV) Disk Galaxies NGC 2541, NGC 5832 and ESO406-042: We present a UV study of 3 extended UV (XUV) galaxies that we have observed with the UVIT and the GMRT. XUV galaxies show filamentary or diffuse star formation well beyond their optical disks, in regions...
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PDRs4All III: JWST's NIR spectroscopic view of the Orion Bar: (Abridged) We investigate the impact of radiative feedback from massive stars on their natal cloud and focus on the transition from the HII region to the atomic PDR (crossing the ionisation front (IF)), and the subsequent transition to the molecular PDR (cro...
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Spherical Harmonic Analysis of the Angular Distribution of Gamma-Ray Bursts: We compute the angular power spectrum C_l of the BATSE 3B catalog, and find no evidence for clustering on any scale. These constraints bridge the entire range from small scales, probing source clustering and repetition, to large scales const...
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High Energy Astroparticle Physics: We give a brief (and highly incomplete) overview of the current experimental and theoretical status of high energy cosmic rays and their secondary gamma-rays and neutrinos. We focus on the role of large scale magnetic fields and on multi-messenger aspects linking these three channels....
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Stellar streams from black hole-rich star clusters: Nearly a hundred progenitor-less, thin stellar streams have been discovered in the Milky Way, thanks to Gaia and related surveys. Most streams are believed to have formed from star clusters and it was recently proposed that extended star clusters -- rich in stellar-ma...
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Engineering physics of superconducting hot-electron bolometer mixers: Superconducting hot-electron bolometers are presently the best performing mixing devices for the frequency range beyond 1.2 THz, where good quality superconductor-insulator-superconductor (SIS) devices do not exist. Their physical appearance is very ...
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Choked accretion: from radial infall to bipolar outflows by breaking spherical symmetry: Steady state, spherically symmetric accretion flows are well understood in terms of the Bondi solution. Spherical symmetry however, is necessarily an idealized approximation to reality. Here we explore the consequences of deviati...
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Rational Approximation Formula for Chandrasekhar's H-function for Isotropic Scattering: We first establish a simple procedure to obtain with 11-figure accuracy the values of Chandrasekhar's H-function for isotropic scattering using a closed-form integral representation and the Gauss-Legendre quadrature. Based on the ...
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The Voyage of Metals in the Universe from Cosmological to Planetary Scales: the need for a Very High-Resolution, High Throughput Soft X-ray Spectrometer: Metals form an essential part of the Universe at all scales. Without metals we would not exist, and the Cosmos would look completely different. Metals are primari...
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Origin of the Galactic Halo: accretion vs. in situ formation: We test the hypothesis that the classical and ultra-faint dwarf spheroidal satellites of the our Galaxy have been the building blocks of the Galactic halo by comparing their [O/Fe] and [Ba/Fe] vs. [Fe/H] patterns with the ones observed in Galactic halo stars...
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The Cluster of Galaxies Abell 970: We present a dynamical analysis of the galaxy cluster Abell 970 based on a new set of radial velocities measured at ESO, Pic du Midi and Haute-Provence observatories. Our analysis indicates that this cluster has a substructure and is out of dynamical equilibrium. This conclusion is al...
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Continuum and line modelling of discs around young stars. I. 300000 disc models for Herschel/GASPS: We have combined the thermo-chemical disc code ProDiMo with the Monte Carlo radiative transfer code MCFOST to calculate a grid of ~300000 circumstellar disc models, systematically varying 11 stellar, disc and dust para...
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The near-infrared size-luminosity relations for Herbig Ae/Be disks: We report the results of a sensitive K-band survey of Herbig Ae/Be disk sizes using the 85-m baseline Keck Interferometer. Targets were chosen to span the maximum range of stellar properties to probe the disk size dependence on luminosity and effective...
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Time resolved spectroscopy of the multiperiodic pulsating subdwarf B star PG1605+072: We present results for the 2m spectroscopic part of the MultiSite Spectroscopic Telescope campaign, which took place in May/June 2002. In order to perform an asteroseismological analysis on the multiperiodic pulsating subdwarf B sta...
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Unveiling the evolutionary state of three B supergiant stars: PU Gem, $ε$ CMa and $η$ CMa: We aim to combine asteroseismology, spectroscopy, and evolutionary models to establish a comprehensive picture of the evolution of Galactic blue supergiant stars (BSG). To start such an investigation, we selected three BSG cand...
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The Oxygen Bottleneck for Technospheres: As oxygen is essential for respiration and metabolism for multicellular organisms on Earth, its presence may be crucial for the development of a complex biosphere on other planets. And because life itself, through photosynthesis, contributed to creating our oxygen-rich atmospher...
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Coupling dark-baryonic matter density profile for vacuum decay scenarios: The cosmological consequences of an interacting model in which vacuum decay law is deducted from the effect that vacuum decay has on the dark matter evolution are investigated. Here, the baryonic matter is also considered as a fluid gravitational...
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Epicyclic frequencies for rotating strange quark stars: the importance of stellar oblateness: Kilohertz QPOs can be used as a probe of the inner regions of accretion disks in compact stars and hence also of the properties of the central object. Most models of kHz QPOs involve epicyclic frequencies to explain their or...
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Spatial correlation function and pairwise velocity dispersion of galaxies: CDM models versus the Las Campanas Survey: We show, with the help of large N-body simulations, that the real-space two-point correlation function and pairwise velocity dispersion of galaxies can both be measured reliably from the Las Campanas ...
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Balmer jump variations of HD 215441 (Babcock's star): Balmer jump discontinuity of the peculiar star HD 215441 was measured on 14 continuous energy distributions obtained by S. J. Adelman at Kitt Peak National and Palomar Observatories. The results show that the Balmer jump vary by about 0.05 dex over the cycle of the ...
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The dynamics of eccentric accretion discs in superhump systems: We have applied an eccentric accretion disc theory in simplified form to the case of an accretion disc in a binary system, where the disc contains the 3:1 Lindblad resonance. This is relevant to the case of superhumps in SU Ursae Majoris cataclysmic variab...
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The habitability of a stagnant-lid Earth: Plate tectonics is a fundamental component for the habitability of the Earth. Yet whether it is a recurrent feature of terrestrial bodies orbiting other stars or unique to the Earth is unknown. The stagnant lid may rather be the most common tectonic expression on such bodies. T...
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The IceCube Neutrino Observatory Part V: Neutrino Oscillations and Supernova Searches: Papers on neutrino oscillation and supernova searches submitted to the 33nd International Cosmic Ray Conference (Rio de Janeiro 2013) by the IceCube Collaboration.
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An analysis of the FIR/RADIO Continuum Correlation in the Small Magellanic Cloud: The local correlation between far-infrared (FIR) emission and radio-continuum (RC) emission for the Small Magellanic Cloud (SMC) is investigated over scales from 3 kpc to 0.01 kpc. Here, we report good FIR/RC correlation down to ~15 pc....
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Imprint of a 2 Myr old source on the cosmic ray anisotropy: We study numerically the anisotropy of the cosmic ray (CR) flux emitted by a single source calculating the trajectories of individual CRs. We show that the contribution of a single source to the observed anisotropy is instead determined solely by the fraction ...
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Hall drift and the braking indices of young pulsars: Braking index measurements of young radio pulsars are all smaller than the value expected for spin down by magnetic dipole braking. We investigate magnetic field evolution in the neutron star crust due to Hall drift as an explanation for observed braking indices. Usi...
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Elastic and breaking properties of epitaxial face-centered crystals in neutron star crusts and white dwarf cores: Crystallization of dense matter in neutron star crusts and white dwarf cores may be similar to epitaxial crystal growth in terrestrial laboratories. However in stellar crystals, the spacing between horizo...
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Faint End of 1.3 mm Number Counts Revealed by ALMA: We present the faint end of number counts at 1.3 mm (238 GHz) obtained with the Atacama Large Millimeter/submillimeter Array (ALMA). Band 6 observations were carried out targeting 20 star-forming galaxies at z ~ 1.4 in the Subaru/XMM-Newton Deep Survey field. In the o...
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Lyot-based Ultra-Fine Pointing Control System for Phase Mask Coronagraphs: High performance coronagraphic imaging at small inner working angle requires efficient control of low order aberrations. The absence of accurate pointing control at small separation not only degrades coronagraph starlight rejection but also in...
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On the accuracy of N-body simulations at very large scales: We examine the deviation of Cold Dark Matter particle trajectories from the Newtonian result as the size of the region under study becomes comparable to or exceeds the particle horizon. To first order in the gravitational potential, the general relativistic re...
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The immediate environment of the Class 0 protostar VLA1623, on scales of ~50-100 AU, observed at millimetre and centimetre wavelengths: We present high angular resolution observations, taken with the Very Large Array (VLA) and Multiple Element Radio Linked Interferometer Network (MERLIN) radio telescopes, at 7mm and ...
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