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Search for Dormant Black Holes in Ellipsoidal Variables I. Revisiting the Expected Amplitudes of the Photometric Modulation: Ellipsoidal variables present light-curve modulations caused by stellar distortion, induced by tidal interaction with their companions. An analytical approximated model of the ellipsoidal modul...
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Gas inside the 97 au cavity around the transition disk Sz\,91: We present ALMA (Cycle 0) band-6 and band-3 observations of the transition disk Sz\,91. The disk inclination and position angle are determined to be $i=49.5\degr\pm3.5\degr$ and $\mathrm{PA}=18.2\degr\pm3.5\degr$ and the dusty and gaseous disk are detected ...
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Diagnosing the Clumpy Protoplanetary Disk of the UXor Type Young Star GM Cephei: UX Orionis stars (UXors) are Herbig Ae/Be or T Tauri stars exhibiting sporadic occultation of stellar light by circumstellar dust. GM\,Cephei is such a UXor in the young ($\sim4$~Myr) open cluster Trumpler\,37, showing prominent infrared...
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Determining the ionization rates of interstellar neutral species using direct-sampling observations of their direct and indirect beams: A good understanding of the ionization rates of neutral species in the heliosphere is important for studies of the heliosphere and planetary atmospheres. So far, the intensities of t...
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A Volume-limited Sample of 63 M7--M9.5 Dwarfs I. Space Motion, Kinematic Age, and Lithium: In a volume-limited sample of 63 ultracool dwarfs of spectral type M7--M9.5, we have obtained high-resolution spectroscopy with UVES at the Very Large Telescope and HIRES at Keck Observatory. In this first paper we introduce ou...
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NSCC -- A New Scheme of Classification of C-rich Stars Devised from Optical and Infrared Observations: A new classification system for carbon-rich stars is presented based on an analysis of 51 AGB carbon stars through the most relevant classifying indices available. The extension incorporated, that also represents th...
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Evidence for a physically bound third component in HD 150136: Context. HD150136 is one of the nearest systems harbouring an O3 star. Although this system was for a long time considered as binary, more recent investigations have suggested the possible existence of a third component. Aims. We present a detailed analysis ...
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When flux standards go wild: white dwarfs in the age of Kepler: White dwarf stars have been used as flux standards for decades, thanks to their staid simplicity. We have empirically tested their photometric stability by analyzing the light curves of 398 high-probability candidates and spectroscopically confirmed white ...
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Properties and applications of a predicted population of runaway He-sdO/B stars ejected from single degenerate He-donor SNe: This study builds on previous works, producing the most extensive prediction of the properties of such a hypothetical population to date, taking into account both Chandrasekhar and non-Chandras...
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The age-metallicity relation in the solar neighbourhood from a pilot sample of white dwarf-main sequence binaries: The age-metallicity relation (AMR) is a fundamental observational constraint for understanding how the Galactic disc formed and evolved chemically in time. However, there is not yet an agreement on the o...
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Investigation of the Progenitors of Nova Explosions: Recurrent novae (RNe) play an important role as one of the suspected progenitor systems of Type Ia supernovae (SNe) which are used as primary distance indicators in cosmology. Thus, it is important to investigate the nature of their central binary systems to determin...
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Release note: Massive peak bagging of red giants in the Kepler field: The NASA satellite Kepler has gathered about 1420 days-long photometric time series for more than 20000 red giant stars. For about 6600 of them also APOGEE spectroscopic parameters are available, making the sample of high interest for various astroph...
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On the relationship between G-band bright point dynamics and their magnetic field strengths: G-band bright points (GBPs) are regarded as good manifestations of magnetic flux concentrations. We aim to investigate the relationship between the dynamic properties of GBPs and their longitudinal magnetic field strengths. H...
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The Solar-Stellar Connection: We discuss how recent advances in observations, theory and numerical simulations have allowed the stellar community to progress in its understanding of stellar convection, rotation and magnetism and to assess the degree to which the Sun and other stars share similar dynamical properties. E...
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Three ways to solve the orbit of KIC11558725: a 10 day beaming sdB+WD binary with a pulsating subdwarf: The recently discovered subdwarf B (sdB) pulsator KIC11558725 features a rich g-mode frequency spectrum, with a few low-amplitude p-modes at short periods, and is a promising target for a seismic study aiming to co...
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The GAPS programme at TNG LII. Spot modeling of V1298 Tau using SpotCCF tool: The intrinsic variability due to the magnetic activity of young active stars is one of the main challenges in detecting and characterising exoplanets. We present a method able to model the stellar photosphere and its surface inhomogeneities...
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Detection of transit timing variations in excess of one hour in the Kepler multi-planet candidate system KOI 806 with the GTC: We report the detection of transit timing variations (TTVs) well in excess of one hour in the Kepler multi-planet candidate system KOI 806. This system exhibits transits consistent with three...
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The Evolution of Circumstellar Disks Surrounding Intermediate Mass Stars: IC 1805: We report the results of a study of the intermediate and high mass stars in the young, rich star-forming complex IC 1805, based on a combination of optical, near-infrared, and mid-infrared photometry, and classification spectra. These ...
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Binary interactions and UV photometry on photometric redshift: Using the Hyperz code (Bolzonella et al. 2000) we present photometric redshift estimates for a random sample of galaxies selected from the SDSS/DR7 and GALEX/DR4, for which spectroscopic redshifts are also available. We confirm that the inclusion of ultra...
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On the vertical-shear instability in astrophysical discs: We explore the linear stability of astrophysical discs exhibiting vertical shear, which arises when there is a radial variation in the temperature or entropy. Such discs are subject to a "vertical-shear instability", which recent nonlinear simulations have shown...
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Radio light curves and imaging of the helium nova V445 Puppis reveal seven years of synchrotron emission: V445 Puppis is the only helium nova observed to date; its eruption in late 2000 showed high velocities up to 8500 km/s and a remarkable bipolar morphology cinched by an equatorial dust disc. Here we present multi...
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The shear-Hall instability in newborn neutron stars: Aims. In the first few minutes of a newborn neutron star's life the Hall effect and differential rotation may both be important. We demonstrate that these two ingredients are sufficient for generating a 'shear-Hall instability' and for studying its excitation conditi...
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Detection of Strong Millimeter Emission from the Circumstellar Dust Disk Around V1094 Sco: Cold and Massive Disk around a T Tauri Star in a Quiescent Accretion Phase?: We present the discovery of a cold massive dust disk around the T Tauri star V1094 Sco in the Lupus molecular cloud from the 1.1 millimeter continuu...
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Mapping the youngest and most massive stars in the Tarantula nebula with MUSE-NFM: The evolution of the most massive stars is a puzzle with many missing pieces. Statistical analyses are the key to provide anchors to calibrate theory, however performing these studies is an arduous job. The state-of-the-art integral fi...
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Short-term variability and mass loss in Be stars V. Space photometry and ground-based spectroscopy of $γ$ Cas: Context. Be stars are physically complex systems that continue to challenge theory to understand their rapid rotation, complex variability and decretion disks. $\gamma$ Cassiopeiae ($\gamma$ Cas) is one such...
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Theory of fossil magnetic field: Theory of fossil magnetic field is based on the observations, analytical estimations and numerical simulations of magnetic flux evolution during star formation in the magnetized cores of molecular clouds. Basic goals, main features of the theory and manifestations of MHD effects in youn...
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Silicate Extinction Profile Based on the Stellar Spectrum by Spitzer/IRS: The 9.7$\mu m$ and 18$\mu m$ interstellar spectral features, arising from the Si--O stretching and O--Si--O bending mode of amorphous silicate dust, are the strongest extinction feature in the infrared. Here we use the "pair method" to determine ...
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Helium-Star Models with Optically Thick Winds: Implications for the Internal Structures and Mass-Loss Rates of Wolf-Rayet Stars: We construct helium (He) star models with optically thick winds and compare them with the properties of Galactic Wolf-Rayet (WR) stars. Hydrostatic He-core solutions are connected smoothly ...
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The IACOB project VIII. Searching for empirical signatures of binarity in fast-rotating O-type stars: The empirical distribution of projected rotational velocities (vsini) in massive O-type stars is characterized by a dominant slow velocity component and a tail of fast rotators. Binary interaction has been proposed t...
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The Color and Brightness of the F-Corona Inferred from the 2019 July 2 Total Solar Eclipse: Total solar eclipses (TSEs) provide a unique opportunity to quantify the properties of the K-corona (electrons), F-corona (dust) and E-corona (ions) continuously from the solar surface out to a few solar radii. We apply a nove...
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Imaging from STIX visibility amplitudes: Aims: To provide the first demonstration of STIX Fourier-transform X-ray imaging using semi-calibrated (amplitude-only) visibility data acquired during the Solar Orbiter's cruise phase. Methods: We use a parametric imaging approach by which STIX visibility amplitudes are fitted ...
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Recycled Pulsars: Spins, Masses and Ages: Recycled pulsars are mainly characterized by their spin periods, B-fields and masses. All these quantities are affected by previous interactions with a companion star in a binary system. Therefore, we can use these quantities as fossil records and learn about binary evolution. ...
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Impacts of fragmented accretion streams onto Classical T Tauri Stars: UV and X-ray emission lines: Context. The accretion process in Classical T Tauri Stars (CTTSs) can be studied through the analysis of some UV and X-ray emission lines which trace hot gas flows and act as diagnostics of the post-shock downfalling pl...
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Coronal Magnetic Field Topology From Total Solar Eclipse Observations: Measuring the global magnetic field of the solar corona remains exceptionally challenging. The fine-scale density structures observed in white light images taken during Total Solar Eclipses (TSEs) are currently the best proxy for inferring the magne...
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A method to identify and characterise binary candidates - a study of CoRoT data: The analysis of the CoRoT space mission data was performed aiming to test a method that selects, among the several light curves observed, the transiting systems that likely host a low-mass star orbiting the main target. The method identi...
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The PASTEL catalogue: 2016 version: The bibliographical compilation of stellar atmospheric parameters (Teff, logg, [Fe/H]) relying on high-resolution, high signal-to-noise spectroscopy started in the eighties with the so-called [Fe/H] catalogue, and was continued in 2010 with the PASTEL catalogue, which also includes d...
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Budget equations and astrophysical nonlinear mean-field dynamos: Solar, stellar and galactic large-scale magnetic fields are originated due to a combined action of non-uniform (differential) rotation and helical motions of plasma via mean-field dynamos. Usually, nonlinear mean-field dynamo theories take into account al...
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Surface distribution of small-scale magnetic field on the active cool star LQ Hydrae: It is well known that small-scale magnetism dominates the surface magnetic field topologies of active late-type stars. However, little information is available on the spatial distribution of this key magnetic field component. Here, ...
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Mid-IR observations of circumstellar disks -- Part III: A mixed sample of PMS stars and Vega-type objects: We present new mid-infrared spectra for a sample of 15 targets (1 FU Orionis object, 4 Herbig Ae stars, 5 T Tauri stars and 5 Vega type stars), obtained with the TIMMI2 camera at La Silla Observatory (ESO). Thre...
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Metallicity estimation of MW, SMC and LMC classical Cepheids from the shape of the $V$- and $I$-band light curves: Estimating metallicity of classical Cepheids is of prime importance for studying metallicity effect on stellar evolution, chemical evolution of galaxies, and ultimately its impact on period-luminosity re...
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On the Correlation between L Dwarf Optical and Infrared Variability and Radio Aurorae: Photometric variability attributed to cloud phenomena is common in L/T transition brown dwarfs. Recent studies show that such variability may also trace aurorae, suggesting that localized magnetic heating may contribute to observed...
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Solar-like stars observed by Kepler: an incredible adventure: The NASA Kepler mission -in flight since March 2009- is producing an enormous number of high-quality continuous light curves. Now, and for the first time ever, we are able to do ensemble asteroseismology, i.e., to do an asteroseismic analysis with a statisti...
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Interacting winds in massive binaries: Massive stars feature highly energetic stellar winds that interact whenever two such stars are bound in a binary system. The signatures of these interactions are nowadays found over a wide range of wavelengths, including the radio domain, the optical band, as well as X-rays and ev...
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Observations of microglitches in HartRAO radio pulsars: A detailed observation of microglitch phenomenon in relatively slow radio pulsars is presented. Our analyses for these small amplitude jumps in pulse rotation frequency ($\nu$) and/or spin down rate ($\dot{\nu}$) combine the traditional manual detection method (wh...
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Water around IRAS15398-3359 observed with ALMA: How protostars accrete mass is one of the fundamental problems of star formation. High column densities and complex kinematical structures make direct observations challenging and they only provide a snapshot. Chemical tracers provide an interesting alternative to charact...
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A survey of nulling pulsars using the Giant Meterwave Radio Telescope: Several pulsars show sudden cessation of pulsed emission, which is known as pulsar nulling. In this paper, the nulling behaviour of 15 pulsars is presented. The nulling fractions of these pulsars, along with the degree of reduction in the pulse ener...
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White-light superflare and long-term activity of the nearby M7 type binary EI~Cnc observed with GWAC system: Stellar white-light flares are believed to play an essential role on the physical and chemical properties of the atmosphere of the surrounding exoplanets. Here we report an optical monitoring campaign on the n...
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Analytical maximum likelihood estimation of stellar magnetic fields: The polarised spectrum of stellar radiation encodes valuable information on the conditions of stellar atmospheres and the magnetic fields that permeate them. In this paper, we give explicit expressions to estimate the magnetic field vector and its ass...
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Bayesian Characterization of Main Sequence Binaries in the Old Open Cluster NGC 188: The binary fractions of open and globular clusters yield powerful constraints on their dynamical state and evolutionary history. We apply publicly available Bayesian analysis code to a $UBVRIJHK_{S}$ photometric catalog of the old op...
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A key factor to the spin parameter of uniformly rotating compact stars: crust structure: We study the key factor to determine the dimensionless spin parameter $j\equiv cJ/(GM^2)$ of different kinds of uniformly rotating compact stars, including the traditional neutron stars, hyperonic neutron stars, and hybrid stars,...
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Massive Outflows Driven by Magnetic Effects II: Comparison with Observations: The driving mechanism of massive outflows observed in high-mass star-forming regions is investigated using three-dimensional magnetohydrodynamics (MHD) and protostellar evolution calculations. In our previous paper, we showed that the mass ...
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Lithium in the Hyades L5 brown dwarf 2MASSJ04183483+2131275: From the luminosity, effective temperature, and age of the Hyades brown dwarf 2MASSJ04183483+2131275 (2M0418), sub-stellar evolutionary models predict a mass in the range 39-55 Jupiter masses (M_Jup) which is insufficient to produce any substantial lithium bu...
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Stability of the coronal magnetic field around large confined and eruptive solar flares: In order to improve our understanding on the pre-requisites of eruptive solar flares, we study and compare different measures that characterize the eruptive potential of solar active regions - the critical height for torus instab...
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The past and future evolution of a star like Betelgeuse: We discuss the physics and the evolution of a typical massive star passing through an evolutionary stage similar to that of Betelgeuse. After a brief introduction recalling various observed parameters of Betelgeuse, we discuss the Pre-Main-Sequence phase (PMS), t...
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Radial Speed Evolution of Interplanetary Coronal Mass Ejections During Solar Cycle 23: We report radial speed evolution of interplanetary coronal mass ejections (ICMEs) detected by the SOHO/LASCO coronagraph, interplanetary scintillation (IPS) at 327 MHz, and in-situ observations. In this study, we analyze solar wind...
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Discovery of three self-lensing binaries from Kepler: We report the discovery of three edge-on binaries with white dwarf companions that gravitationally magnify (instead of eclipsing) the light of their stellar primaries, as revealed by a systematic search for pulses with long periods in the Kepler photometry. We joint...
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Astrometric detection of exoplanets from the ground: Astrometry is a powerful technique to study the populations of extrasolar planets around nearby stars. It gives access to a unique parameter space and is therefore required for obtaining a comprehensive picture of the properties, abundances, and architectures of exop...
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Exploring the spectral \textit{information content} in the LAMOST medium-resolution survey (MRS): Low-resolution spectra are proved competitive to high-resolution spectra in determining many stellar labels at comparable precision. It is useful to consider the spectral information content when assessing the capability...
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Signatures of ubiquitous magnetic reconnection in the deep atmosphere of sunspot penumbrae: Ellerman bombs are regions with enhanced Balmer line wing emission and mark magnetic reconnection in the deep solar atmosphere in active regions and quiet Sun. They are often found in regions where opposite magnetic polarities...
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The process of data formation for the Spectrometer/Telescope for Imaging X-rays (STIX) in Solar Orbiter: The Spectrometer/Telescope for Imaging X-rays (STIX) is a hard X-ray imaging spectroscopy device to be mounted in the Solar Orbiter cluster with the aim of providing images and spectra of solar flaring regions at ...
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Dust-temperature of an isolated star-forming cloud: Herschel observations of the Bok globule CB244: We present Herschel observations of the isolated, low-mass star-forming Bok globule CB244. It contains two cold sources, a low-mass Class 0 protostar and a starless core, which is likely to be prestellar in nature, sep...
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A new extremely low-mass white dwarf in the NLTT catalogue: We report on the discovery of the extremely low-mass, hydrogen-rich white dwarf, NLTT 11748. Based on measurements of the effective temperature (8540+/-50 K) and surface gravity (log g = 6.20+/-0.15) obtained by fitting the observed Balmer line profiles with s...
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Formation of Extremely Low-mass White Dwarfs Binaries: Motivated by the discovery of a handful of pulsating, extremely low mass white dwarfs (ELM WDs, mass $M \lesssim 0.17\, M_\odot$) which likely have WD companions, this paper discusses binary formation models for these systems. Formation of an ELM WD by unstable mas...
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Neutrino Quantum Kinetic Equations: Neutrinos propagate in astrophysical and cosmological environments modifying their flavor in intriguing ways. The study of neutrino propagation in media is based on the mean-field, extended mean-field and Boltzmann equations. We summarise salient features of these evolution equations...
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The nature of Elsässer variables in compressible MHD: The Els\"{a}sser variables are often used in studies of plasma turbulence, in helping differentiate between MHD waves propagating parallel or anti-parallel to the main magnetic field. While for pure Alfv\'en waves in a homogeneous plasma the method is strictly valid...
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Algebraic and machine learning approach to hierarchical triple-star stability: We present two approaches to determine the dynamical stability of a hierarchical triple-star system. The first is an improvement on the Mardling-Aarseth stability formula from 2001, where we introduce a dependence on inner orbital eccentri...
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Colors of c-type RR Lyrae Stars and Interstellar Reddening: RR Lyrae stars pulsating in the fundamental mode have long been used to measure interstellar reddening, based on their observed uniformity of $B-V$ color at minimum light after small corrections for metallicity and period are applied. However, little attention...
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Chromospheric magnetic field: A comparison of He I 10830 A observations with nonlinear force-free field extrapolation: The nonlinear force-free field (NLFFF) modeling has been extensively used to infer the three-dimensional (3D) magnetic field in the solar corona. One of the assumptions in the NLFFF extrapolation is ...
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The geometry of the close environment of SV Psc as probed by VLTI/MIDI: Context. SV Psc is an asymptotic giant branch (AGB) star surrounded by an oxygen-rich dust envelope. The mm-CO line profile of the object's outflow shows a clear double-component structure. Because of the high angular resolution, mid-IR interferome...
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Asteroseismic stellar activity relations: In asteroseismology an important diagnostic of the evolutionary status of a star is the small frequency separation which is sensitive to the gradient of the mean molecular weight in the stellar interior. It is thus interesting to discuss the classical age-activity relations in ...
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The rapid dispersal of low-mass virialised clusters: Infant mortality brought about by the expulsion of a star cluster's natal gas is widely invoked to explain cluster statistics at different ages. While a well studied problem, most recent studies of gas expulsion's effect on a cluster have focused on massive clusters,...
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Variability in Hot Carbon-Dominated Atmosphere (hot DQ) White Dwarfs: Rapid Rotation?: Hot white dwarfs with carbon-dominated atmospheres (hot DQs) are a cryptic class of white dwarfs. In addition to their deficiency of hydrogen and helium, most of these stars are highly magnetic, and a large fraction vary in luminos...
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The gravitational redshift of solar-type stars from Gaia DR3 wide binaries: Light escaping from a gravitational potential suffers a redshift with magnitude proportional to the depth of the potential. This "gravitational redshift" is easily measurable in dense stars such as white dwarfs, but is much weaker and has eva...
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Consecutive Narrow and Broad Quasi-periodic Fast-propagating Wave Trains Associated with a Flare: The excitation mechanism of coronal quasi-period fast-propagating (QFP) wave trains remains unresolved. Using Atmospheric Imaging Assembly onboard the Solar Dynamics Observatory observations, we study a narrow and a broa...
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Panchromatic evolution of three luminous red novae: Forbidden hugs in pandemic times -- IV: We present photometric and spectroscopic data on three extragalactic luminous red novae (LRNe): AT2018bwo, AT2021afy, and AT2021blu. AT2018bwo was discovered in NGC45 (at 6.8 Mpc) a few weeks after the outburst onset. During t...
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EPIC 216747137: a new HW Vir eclipsing binary with a massive sdOB primary and a low-mass M-dwarf companion: EPIC 216747137 is a new HW~Virginis system discovered by the Kepler spacecraft during its K2 "second life". Like the other HW Vir systems, EPIC 216747137 is a post-common-envelope eclipsing binary consisting of...
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Damping of filament thread oscillations: effect of the slow continuum: Transverse oscillations of small amplitude are commonly seen in high-resolution observations of filament threads, i.e. the fine-structures of solar filaments/prominences, and are typically damped in a few periods. Kink wave modes supported by the th...
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Radial velocity photon limits for the dwarf stars of spectral classes F--M: The determination of extrasolar planet masses with the radial velocity (RV) technique requires spectroscopic Doppler information from the planet's host star, which varies with stellar brightness and temperature. We analyze Doppler information...
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CSI 2264: Characterizing Young Stars in NGC 2264 with Stochastically Varying Light Curves: We provide CoRoT and Spitzer light curves, as well as broad-band multi-wavelength photometry and high resolution, multi- and single-epoch spectroscopy for 17 classical T Tauris in NGC 2264 whose CoRoT light curves (LCs) exempli...
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Classical Cepheids Require Enhanced Mass Loss: Measurements of rates of period change of Classical Cepheids probe stellar physics and evolution. Additionally, better understanding of Cepheid structure and evolution provides greater insight into their use as standard candles and tools for measuring the Hubble constant. ...
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The quasi-biennial periodicity as a window on the solar magnetic dynamo configuration: Manifestations of the solar magnetic activity through periodicities of about 11 and 2 years are now clearly seen in all solar activity indices.In this paper, we add information about the mechanism driving the 2 year period by study...
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Nature of grand minima and maxima from fully non-linear Flux-Transport Dynamos: We aim to investigate the nature and occurrence characteristics of grand solar minimum and maximum periods, which are observed in the solar proxy records such as 10Be and 14C, using a fully non-linear Babcock-Leighton type flux-transport ...
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The Envelope Kinematics and a Possible Disk Around the Class 0 Protostar within BHR7: We present a characterization of the protostar embedded within the BHR7 dark cloud, based on both photometric measurements from the near-infrared to millimeter and interferometric continuum and molecular line observations at millime...
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Tests of sunspot number sequences: 4. Discontinuities around 1946 in various sunspot number and sunspot group number reconstructions: We use 5 test data series to quantify putative discontinuities around 1946 in 5 annual-mean sunspot number or group number sequences. The series tested are: the original and new versio...
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A Theory about Electric Current and Heating in Plasma: The traditional generalized Ohm's law in MHD do not explicitly present the relation of electric currents and electric fields in fully ionized plasma, and lead to some unexpected concepts, such as "the magnetic frozen-in plasma", magnetic reconnection etc. In the pr...
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A blueprint of state-of-the-art techniques for detecting quasi-periodic pulsations in solar and stellar flares: Quasi-periodic pulsations (QPPs) appear to be a common feature observed in the light curves of both solar and stellar flares. However, their quasi-periodic nature, along with the fact that they can be small...
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The Lyman-alpha Emission in Solar Flares. I. a Statistical Study on Its Relationship with the 1--8 Å Soft X-ray Emission: We statistically study the relationship between the Lyman-alpha (\lya) and 1--8 \AA\ soft X-ray (SXR) emissions from 658 M- and X-class solar flares observed by the {\em Geostationary Operational ...
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Coronal Hole and Solar Global Magnetic Field Evolution in 1976-2012: Coronal hole spatial-temporal evolution is studied and comparison made with that of the solar global magnetic field in cycles 21-23 (1976-2012). The latitude-longitude distribution dynamics of coronal holes and the regularities in the global magnetic ...
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Absolute dimensions of detached eclipsing binaries. II. The metallic-lined system XY Ceti: We present phase-resolved spectroscopy and extensive survey photometry of the detached eclipsing binary system XY Cet, which is composed of two metallic-lined stars. We measure their masses to be 1.773 +/- 0.016 and 1.615 +/- 0...
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Disk Evolution in OB Associations - Deep Spitzer/IRAC Observations of IC 1795: We present a deep Spitzer/IRAC survey of the OB association IC 1795 carried out to investigate the evolution of protoplanetary disks in regions of massive star formation. Combining Spitzer/IRAC data with Chandra/ACIS observations, we find ...
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The Intricate Structure of HH 508, the Brightest Microjet in the Orion Nebula: We present Magellan adaptive optics H$\alpha$ imaging of HH 508, which has the highest surface brightness among protostellar jets in the Orion Nebula. We find that HH 508 actually has a shorter component to the west, and a longer and knott...
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Dynamics of fast and slow magnetoacoustic waves in plasma slabs with thermal misbalance: Non-uniformity of the solar atmosphere along with the presence of non-adiabatic processes such as radiation cooling and unspecified heating can significantly affect the dynamics and properties of magnetoacoustic (MA) waves. To ad...
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Forward seismic modelling of the pulsating magnetic B-type star HD 43317: The large-scale magnetic fields detected at the surface of about 10% of hot stars extend into the stellar interior, where they may alter the structure. Deep inner regions of stars are only observable using asteroseismology. Here, we investigated ...
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The magnetic field of the double-lined spectroscopic binary system HD 5550: (Abridged) In the framework of the BinaMicS project, we have begun a study of the magnetic properties of a sample of intermediate-mass and massive short-period binary systems, as a function of binarity properties. We report in this paper the ...
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Evolving waves and turbulence in the outer corona and inner heliosphere: the accelerating expanding box: Alfv\'enic fluctuations in the solar wind display many properties reflecting an ongoing nonlinear cascade, e.g. a well-defined spectrum in frequency, together with some characteristics more commonly associated wit...
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Time delay between outer heliosheath crossing and observation of interstellar neutral atoms: In situ measurements of the heliospheric particle populations by the Voyager spacecraft can only be put in an appropriate context with remote-sensing observations of energetic and interstellar neutral atoms (ENAs and ISN, res...
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Explaining the Early Exit of Eta Carinae from its 2009 X-Ray Minimum with the Accretion Model: We use the accretion model to explain the early exit of Eta Carinae from its 2009 X-ray minimum. In the accretion model the secondary star accretes mass from the primary wind near periastron passage, a process that suppress...
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The VMC Survey - XIV. First results on the look-back time star-formation rate tomography of the Small Magellanic Cloud: We analyse deep images from the VISTA survey of the Magellanic Clouds in the YJKs filters, covering 14 sqrdeg (10 tiles), split into 120 subregions, and comprising the main body and Wing of the Smal...
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Destination exoplanet: Habitability conditions influenced bystellar winds properties: The cumulative effect of the magnetized stellar winds on exoplanets dominates over other forms of star-planet interactions. When combined with photoevaporation, these winds will lead to atmospheric erosion. This is directly connecte...
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Convective scale and subadiabatic layers in simulations of rotating compressible convection: (abridged) Context: Rotation is thought to influence the size of convective eddies and the efficiency of convective energy transport in the deep convection zones of stars. Rotationally constrained convection has been invoked ...
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