Search Publications
Abundant sub-micron grains revealed in newly discovered extreme debris discs
Henning, Thomas; Moór, Attila; Pawellek, Nicole +7 more
Extreme debris discs (EDDs) are bright and warm circumstellar dusty structures around main sequence stars. They may represent the outcome of giant collisions occuring in the terrestrial region between large planetesimals or planetary bodies, and thus provide a rare opportunity to peer into the aftermaths of these events. Here, we report on results…
Survey of Variables with the ILMT
Kumar, Brajesh; Surdej, Jean; Negi, Vibhore +11 more
Nestled in the mountains of Northern India, is a 4-metre rotating dish of liquid mercury. Over a 10-year period, the International Liquid Mirror Telescope (ILMT) will survey 117 square degrees of sky, to study the astrometric and photometric variability of all detected objects. One of the scientific programs will be a survey of variable stars. The…
A multi-wavelength study of Galactic H II regions with extended emission
Wyrowski, Friedrich; Menten, Karl M.; Dzib, Sergio A. +9 more
Context. H II regions are the signposts of massive (M ≥ 8 M⊙) star-forming sites in our Galaxy. It has been observed that the ionizing photon rate inferred from the radio continuum emission of H II regions is significantly lower (~90%) than that inferred from far-infrared fluxes measured by the Infrared Astronomical Satellite. Aims. Thi…
Winds of change: The nuclear and galaxy-scale outflows and the X-ray variability of 2MASS 0918+2117
Buchner, J.; Merloni, A.; Vignali, C. +21 more
Context. In this work, we test feedback propagation models on the test case of 2MASS 0918+2117 (2M0918), a z = 0.149 X-ray variable AGN that shows tentative evidence for nuclear ultra-fast outflows (UFOs) in a 2005 XMM-Newton observation. We also investigate whether UFOs can be related to the observed X-ray variability.
Aims: We observed 2M09…
Stellar Characterization and a Chromospheric Activity Analysis of a K2 Sample of Planet-hosting Stars
Cunha, Katia; Smith, Verne V.; Quispe-Huaynasi, F. +4 more
Effective temperatures, surface gravities, and iron abundances were derived for 109 stars observed by the K2 mission using equivalent width measurements of Fe I and Fe II lines. Calculations were carried out in local thermodynamic equilibrium using Kurucz model atmospheres. Stellar masses and radii were derived by combining the stellar parameters …
Evidence for magnetic boundary layer accretion in RU Lup: A spectrophotometric analysis
Alcalá, J. M.; Manara, C. F.; Frasca, A. +9 more
Context. It is well established that classical T Tauri stars accrete material from a circumstellar disk through magnetic fields. However, the physics regulating the processes in the inner (0.1 AU) disk is still not well understood. Aims. Our aim is to characterize the accretion process of the classical T Tauri Star RU Lup. Methods. Optical high-re…
UVIT Survey of the Host Galaxies of Active Galactic Nuclei. I. Star Formation Scenarios
Stalin, C. S.; Nandi, Payel; Saikia, D. J. +1 more
Circumnuclear star formation (SF) is generally seen in galaxies hosting active galactic nuclei (AGN); however, the connection between the AGN activity and SF in them is less well understood. To explore this connection on scales of a few tens of parsecs to a few tens of kiloparsecs and larger, we carried out an investigation of SF in seven Seyfert-…
Demography of Stellar Radio Population within 500 pc: A VLASS-Gaia DR3 Study
Narang, Mayank; Tyagi, H.; Shridharan, B. +5 more
In this work, we have carried out a systematic analysis of the Very Large Array Sky Survey (VLASS) quick look catalogs together with Gaia DR3 to identify the optical counterparts of 3 GHz radio emitters within 500 pc to obtain a homogeneous statistical sample of stellar radio sources. We have identified distinct populations of 3 GHz emitters acros…
Hα Emission and H II Regions at the Locations of Recent Supernovae in Nearby Galaxies
Leroy, Adam K.; Chevance, Mélanie; Glover, Simon C. O. +22 more
We present a statistical analysis of the local, ≈50–100 pc scale, Hα emission at the locations of recent (≤125 yr) supernovae (SNe) in nearby star-forming galaxies. Our sample consists of 32 SNe in 10 galaxies that are targets of the PHANGS-MUSE survey. We find that 41% (13/32) of these SNe occur coincident with a previously identified H II region…
A New Rarity Assessment of the "Disk of Satellites": The Milky Way System Is the Exception Rather Than the Rule in the ΛCDM Cosmology
Yoon, Suk-Jin; Paudel, Sanjaya; Moon, Jun-Sung +2 more
The majority of satellite galaxies around the Milky Way (MW) show disk-like distributions (the disk of satellites; DoS), which is a small-scale problem of the lambda cold dark matter cosmology. The conventional definition of the MW-like DoS is a satellite system with a minor-to-major axis ratio (c/a) lower than the MW's c/a value of 0.181. Here, w…