Search Publications
Understanding the universal dust attenuation scaling relation of star-forming galaxies
Zheng, Xian Zhong; An, Fang Xia; Xu, Haiguang +17 more
Star-forming galaxies (SFGs) adhere to a surprisingly tight scaling relation of dust attenuation parametrized by the infrared excess (IRX≡ LIR/LUV), being jointly determined by the star formation rate (SFR), galaxy size (Re), metallicity (Z/Z⊙), and axial ratio (b/a). We examine how these galaxy paramete…
Estimating Gradients Of Physical Fields In Space
Shen, Chao; Zhou, Yufei
This study focuses on the development of a multi-point technique for future constellation missions, aiming to measure gradients at various orders, in particular the linear and quadratic gradients, of a general field. It is well established that, in order to estimate linear gradients, the spacecraft must not lie on a plane. Through analytical explo…
An Elemental Abundance Diagnostic for Coordinated Solar Orbiter/SPICE and Hinode/EIS Observations
Matthews, Sarah A.; Warren, Harry P.; Brooks, David H. +2 more
Plasma composition measurements are a vital tool for the success of current and future solar missions, but density- and temperature-insensitive spectroscopic diagnostic ratios are sparse, and their underlying accuracy in determining the magnitude of the first ionization potential (FIP) effect in the solar atmosphere remains an open question. Here …
Peculiarities of the chemical enrichment of metal-poor stars in the Milky Way Galaxy★
Kniazev, A. Yu.; Soubiran, C.; Korotin, S. A. +5 more
Context. The oldest stars in the Milky Way are metal-poor with [Fe/H] < −1.0, displaying peculiar elemental abundances compared to solar values. The relative variations in the chemical compositions among stars is also increasing with decreasing stellar metallicity, allowing for the pure signature of unique nucleosynthesis processes to be reveal…
The colliding-wind binary HD 168112
Blomme, R.; Nazé, Y.; Rauw, G. +2 more
Context. Radio surveys of early-type stars have revealed a number of non-thermal emitters. Most of these have been shown to be binaries, where the collision between the two stellar winds is responsible for the non-thermal emission.
Aims: HD 168112 is a non-thermal radio emitter, whose binary nature has only recently been confirmed spectroscop…
Flickering pulsations in bright X-ray pulsars: the evidence of gravitationally lensed and eclipsed accretion column
Tsygankov, Sergey S.; Mushtukov, Alexander A.; Mereminskiy, Ilya A. +1 more
It is expected that the extreme mass accretion rate onto strongly magnetized neutron stars results in the appearance of accretion columns above the stellar surface. For a distant observer, rotation of a star results in periodic variations of X-ray flux. Because the mass accretion rate fluctuates around the average value, the pulse profiles are not…
Model-independent test of the running Hubble constant from the Type Ia supernovae and the Hubble parameter data
Zhang, Kaituo; Xu, Bing; Xu, Jiancheng +2 more
In this study, we model-independently investigate the behaviour of running Hubble constant, characterized by the fit function $H_{\rm 0}(z)=\tilde{H_{\rm {0}}}/(1+z)^{\alpha }$, where α represents the evolutionary parameter and ${\tilde{H_{\rm {0}}}}$ corresponds to the current value of Hubble constant. Our analysis utilizes the expansion rate E(z…
Observational mapping of the mass discrepancy in eclipsing binaries: Selection of the sample and its photometric and spectroscopic properties
Bowman, Dominic M.; Tkachenko, Andrew; Gebruers, Sarah +4 more
Context. Eclipsing spectroscopic double-lined binaries are the prime source of precise and accurate measurements of masses and radii of stars. These measurements provide a stringent test for models of stellar evolution that are consistently reported to contain major shortcomings.
Aims: The mass discrepancy observed for eclipsing spectroscopic…
Hubble Space Telescope survey of Magellanic Cloud star clusters. Binaries among the split main sequences of NGC 1818, NGC 1850, and NGC 2164
Milone, A. P.; Cordoni, G.; Marino, A. F. +15 more
Nearly all star clusters younger than ~600 Myr exhibit extended main sequence turnoffs and split main sequences (MSs) in their color-magnitude diagrams. Works based on both photometry and spectroscopy have clearly demonstrated that the red MS is composed of fast-rotating stars, whereas blue-MS stars are slow rotators. Nevertheless, the mechanism r…
Retrieving stellar parameters and dynamics of AGB stars with Gaia parallax measurements and CO5BOLD RHD simulations
Chiavassa, A.; Uttenthaler, S.; Freytag, B. +2 more
Context. The complex dynamics of asymptotic giant branch (AGB) stars and the resulting stellar winds have a significant impact on the measurements of stellar parameters and amplify their uncertainties. Three-dimensional (3D) radiative hydrodynamic (RHD) simulations of convection suggest that convection-related structures at the surface of AGB star…