Search Publications
When LAMOST meets Gaia DR3: Exploring the metallicity of open clusters
Fu, Xiaoting; Wang, Luqian; Han, Zhanwen +8 more
Context. Open clusters (OCs) are excellent probes as their age and abundance can be tightly constrained, allowing us to explore the distribution of metallicity and composition across the disk of the Milky Way. By conducting a comprehensive analysis of the metallicity of OCs, we can obtain valuable information about the history of their chemical en…
Orbits and masses in two triple systems
Tokovinin, Andrei; Nazor, Dinko
In an effort to determine accurate orbital and physical properties of a large number of bright stars, a method was developed to fit simultaneously stellar parameters (masses, luminosities, effective temperatures), distance, and orbits to the available data on multiple systems, namely the combined and differential photometry, positional measurement…
XMM-Newton's view of a RS CVn binary CF Tuc
Sriram, K.; Agrawal, Vivek K.; Lahiri, Deblina +1 more
Coronal emission exhibited by the chromospherically active binaries is important to understand the underlying mechanism. We report the X-ray spectral studies of an RS CVn source CF Tuc using XMM-Newton archival data. The light curve was found to be steady with no flaring activity and the source was in a quiescent X-ray emission state. The source s…
Radio Morphology of Gamma-Ray Sources: Double-lobed Radio Sources
Stalin, C. S.; Saikia, D. J.; Domínguez, Alberto +1 more
The extragalactic γ-ray sky is dominated by relativistic jets aligned to the observer's line of sight, i.e., blazars. A few of their misaligned counterparts, e.g., radio galaxies, are also detected with the Fermi-Large Area Telescope (LAT), albeit in a small number (∼50), indicating the crucial role played by the jet viewing angle in detecting γ-r…
Selecting Erosion- and Deposition-Dominated Zones in the Jezero Delta Using a Water Flow Model for Targeting Future In Situ Mars Surface Missions
Steinmann, Vilmos; Kereszturi, Ákos; Bahia, Rickbir Singh
Identifying surface sites with significant astrobiological potential on Mars requires a comprehensive understanding of past geological processes and conditions there, including the shallow subsurface region. Numerical modelling could distinguish between regions dominated by erosion and those characterized by sediment accumulation in ancient wet en…
Deep Chandra Observations of NGC 5728. III. Probing the High-resolution X-Ray Morphology and Multiphase Interstellar Medium Interactions in the Circumnuclear Region
Elvis, M.; Fabbiano, G.; Maksym, W. P. +2 more
We present a detailed imaging analysis of 260 ks of subarcsecond resolution Chandra (ACIS-S) observations of the nearby Seyfert 2 galaxy NGC 5728. Our study focuses on the bright and diffuse soft X-ray emission within the galaxy's inner ∼1 kpc. By comparing the X-ray emission across different energy bands, we identify localized variations in the a…
Time-lapse Very Long Baseline Interferometry Imaging of the Close Active Binary HR 1099
Golay, Walter W.; Mutel, Robert L.; Abbuhl, Evan E.
We report multiepoch astrometric very long baseline interferometry observations of the chromospherically active binary HR 1099 (V711 Tau, HD 22468) at six epochs over 63 days using the Very Long Baseline Array at 22.2 GHz. We determined hourly radio positions at each epoch with a positional uncertainty significantly smaller than the component sepa…
A binary supernova OB-runaway candidate inside Berkeley 97
Neuhäuser, R.; Mugrauer, M.; Michel, K. -U. +5 more
Aims. OB-runaway stars ejected by the binary supernova mechanism can be found near young open star clusters. In this paper, we present an OB-runaway candidate as a pre-SN binary companion to the progenitor of the pulsar PSR J2238+5903 inside the young open star cluster Berkeley 97. Methods. We tried to find a kinematic outlier based on Gaia DR3 pr…
A catalogue of merging clusters of galaxies: cluster partners, merging subclusters, and post-collision clusters
Yuan, Z. S.; Han, J. L.; Wen, Z. L.
Clusters of galaxies are merging during the formation of large-scale structures in the Universe. Based on optical survey data, we identify a large sample of pre-mergers of galaxy clusters and merging subclusters in rich clusters. We find 39 382 partners within a velocity difference of 1500 km s$^{-1}$ and a projected separation of 5 $r_{500}$ arou…
Dynamical mass determination and partial eclipses of the heartbeat star HD 181793
Wilson, Thomas G.; Collier Cameron, Andrew; Uronen, Laura E.
We identify the bright Am-type star HD 181793 to be a previously unknown eclipsing, chemically peculiar heartbeat binary, the second of its kind known. The system carries an orbital period of $P = 11.47578275 \pm 0.00000055$ d. We use TESS photometry and LCOGT NRES radial velocity data to build a self-consistent orbital model and determine the fun…