Search Publications
Breaking degeneracies in exoplanetary parameters through self-consistent atmosphere–interior modelling
Lagrange, A. -M.; Wilkinson, C.; Charnay, B. +5 more
Context. With a new generation of observational instruments largely dedicated to exoplanets (i.e. JWST, ELTs, PLATO, and Ariel) providing atmospheric spectra and mass and radius measurements for large exoplanet populations, the planetary models used to understand the findings are being put to the test. Aims. We seek to develop a new planetary mode…
Dark matter limits from the tip of the red giant branch of globular clusters
Hong, Haozhi; Vincent, Aaron C.
Capture and annihilation of weakly interacting massive particle (WIMP)-like dark matter in red giant stars can lead to faster-than-expected ignition of the helium core, and thus a lower tip of the red giant branch (TRGB) luminosity. We use Gaia data to place constraints on the dark matter-nucleon cross section using 22 globular clusters with measu…
Discovery of a Barium Blue Straggler Star in M67 and "Sighting" of Its White Dwarf Companion
Jadhav, Vikrant V.; Reddy, Arumalla B. S.; Subramaniam, Annapurni +1 more
We report the discovery of a barium blue straggler star (BSS) in M67, exhibiting enhancements in slow neutron-capture (s-)process elements. Spectroscopic analysis of two BSSs (WOCS 9005 & WOCS 1020) and four stars located near the main-sequence turn-off using GALAH spectra, showed that WOCS 9005 has a significantly high abundance of the s-proc…
Six new eccentric eclipsing systems with a third body
Wolf, M.; Zasche, P.; Henzl, Z.
We present the discovery of six new triple stellar system candidates composed of an inner eccentric-orbit eclipsing binary with an apsidal motion. These stars were studied using new, precise TESS light curves and a long-term collection of older photometric ground-based data. These data were used for the monitoring of ETVs (eclipse timing variation…
Detecting Exoplanet Transits with the Next Generation of X-Ray Telescopes
Cilley, Raven; King, George W.; Corrales, Lía
Detecting exoplanet transits at X-ray wavelengths would provide a window into the effects of high-energy irradiation on the upper atmospheres of planets. However, stars are relatively dim in the X-ray, making exoplanet transit detections difficult with current X-ray telescopes. To date, only one exoplanet (HD 189733 b) has an X-ray transit detecti…
Phase angle dependence of the dust cross section in a cometary coma. A simple numerical model
Agarwal, J.; Markkanen, J.; Keiser, F.
Context. Rosetta/OSIRIS took optical measurements of the intensity of scattered light from the coma of 67P/Churyumov-Gerasimenko over a wide range of phase angles. These data have been used to measure the phase angle dependent radiance profile of the dust coma.
Aims: We want to provide information about the column area densities of the dust c…
Spatial Relationship between CMEs and Prominence Eruptions during SC 24 and SC 25
Gopalswamy, Nat; Yashiro, Seiji; Michalek, Grzegorz +2 more
During their propagation, coronal mass ejections (CMEs) and prominences sometimes display a nonradial motion. During the years after the solar minimum, the CME central position angle tended to be offset closer to the equator compared to that of the associated prominence eruptions (PE). No such effect was observed during solar maximum. The purpose …
NGTS discovery of a highly inflated Saturn-mass planet and a highly irradiated hot Jupiter. NGTS-26 b and NGTS-27 b
Bouchy, F.; Erikson, A.; Alves, D. R. +31 more
We report the discovery of two new transiting giant exoplanets NGTS-26 b and NGTS-27 b by the Next Generation Transit Survey (NGTS). NGTS-26 b orbits around a G6-type main sequence star every 4.52 days. It has a mass of 0.29-0.06+0.07 MJup and a radius of 1.33-0.05+0.06 RJup making …
A Temperature or Far-ultraviolet Tracer? The HNC/HCN Ratio in M83 on the Scale of Giant Molecular Clouds
Saito, Toshiki; Watanabe, Yoshimasa; Nishimura, Yuri +2 more
The HNC/HCN ratio is observationally known as a thermometer in Galactic interstellar molecular clouds. A recent study has alternatively suggested that the HNC/HCN ratio is affected by the ultraviolet (UV) field, not by the temperature. We aim to study this ratio on the scale of giant molecular clouds in the barred spiral galaxy M83 towards the sou…
Search for interacting galaxy clusters from SDSS DR-17 employing optimized friends-of-friends algorithm and multimessenger tracers
Paul, Surajit; Oak, Tejas
In the theoretical framework of hierarchical structure formation, galaxy clusters evolve through continuous accretion and mergers of substructures. Cosmological simulations have revealed the best picture of the universe as a 3D filamentary network of dark-matter distribution called the cosmic web. Galaxy clusters are found to form at the nodes of …