Search Publications
Quantitative spectroscopy of late O-type main-sequence stars with a hybrid non-LTE method
Butler, K.; Przybilla, N.; Aschenbrenner, P.
Context. Late O-type stars at luminosities log L/L⊙ ≲ 5.2 show weak winds with mass-loss rates lower than 10−8 M⊙ yr−1. This implies that, unlike their more massive and more luminous siblings, their photospheric layers are not strongly affected by the stellar wind.
Aims: A hybrid non-local thermodyn…
WASP-131 b with ESPRESSO - I. A bloated sub-Saturn on a polar orbit around a differentially rotating solar-type star
Lafarga, M.; Lendl, M.; Allart, R. +17 more
In this paper, we present observations of two high-resolution transit data sets obtained with ESPRESSO of the bloated sub-Saturn planet WASP-131 b. We have simultaneous photometric observations with NGTS and EulerCam. In addition, we utilized photometric light curves from TESS, WASP, EulerCam, and TRAPPIST of multiple transits to fit for the plane…
Photometric study of the late-time near-infrared plateau in Type Ia supernovae
Galbany, L.; Inserra, C.; Gutiérrez, C. P. +23 more
We present an in-depth study of the late-time near-infrared plateau in Type Ia supernovae (SNe Ia), which occurs between 70 and 500 d. We double the existing sample of SNe Ia observed during the late-time near-infrared plateau with new observations taken with the Hubble Space Telescope, Gemini, New Technology Telescope, the 3.5-m Calar Alto Telesc…
On the Origin of Radio-loudness in Active Galactic Nuclei Using Far-infrared Polarimetric Observations
Lopez-Rodriguez, Enrique; Blandford, Roger; Begelman, Mitchell C. +3 more
The dichotomy between radio-loud (RL) and radio-quiet (RQ) active galactic nuclei (AGNs) is thought to be intrinsically related to radio jet production. This difference may be explained by the presence of a strong magnetic field (B-field) that enhances, or is the cause of, the accretion activity and the jet power. Here we report the first evidence…
CGM2 + CASBaH: The Mass Dependence of H I Lyα-Galaxy Clustering and the Extent of the CGM
Tripp, Todd M.; Prochaska, J. Xavier; Tejos, Nicolas +9 more
We combine data sets from the CGM2 and CASBaH surveys to model a transition point, R cross, between circumgalactic and intergalactic media (CGM and IGM, respectively). In total, our data consist of 7244 galaxies at z < 0.5 with precisely measured spectroscopic redshifts, all having impact parameters of 0.01-20 comoving Mpc…
Evolution of dynamic fibrils from the cooler chromosphere to the hotter corona
Teriaca, Luca; Solanki, Sami K.; Long, David M. +17 more
Dynamic fibrils (DFs) are commonly observed chromospheric features in solar active regions. Recent observations from the Extreme Ultraviolet Imager (EUI) aboard the Solar Orbiter have revealed unambiguous signatures of DFs at the coronal base in extreme ultraviolet (EUV) emission. However, it remains unclear if the DFs detected in the EUV are link…
The Great Dimming of the Hypergiant Star RW Cephei: CHARA Array Images and Spectral Analysis
Gies, Douglas R.; Monnier, John D.; Schaefer, Gail H. +15 more
The cool hypergiant star RW Cephei is currently in a deep photometric minimum that began several years ago. This event bears a strong similarity to the Great Dimming of the red supergiant Betelgeuse that occurred in 2019-2020. We present the first resolved images of RW Cephei that we obtained with the CHARA Array interferometer. The angular diamet…
TOI-1736 and TOI-2141: Two systems including sub-Neptunes around solar analogs revealed by TESS and SOPHIE
Deleuil, M.; Moutou, C.; Winn, J. N. +32 more
Planetary systems around solar analogs inform us about how planets form and evolve in Solar System-like environments. We report the detection and characterization of two planetary systems around the solar analogs TOI-1736 and TOI-2141 using TESS photometry data and spectroscopic data obtained with the SOPHIE instrument on the 1.93 m telescope at t…
Benchmarking Gaia DR3 Apsis with the Hyades and Pleiades open clusters
Brandner, Wolfgang; Calissendorff, Per; Kopytova, Taisiya
Context. The Gaia astrophysical parameters inference system (Apsis) provides astrophysical parameter estimates for several to hundreds of millions of stars.
Aims: We aim to benchmark Gaia DR3 Apsis.
Methods: We compiled approximately 1500 bona fide single stars in the Hyades and Pleiades open clusters for validation of PARSEC isochrones,…
Revising the properties of low mass eclipsing binary stars using TESS light curves
Maxted, P. F. L.; Southworth, J.; Mancini, L. +1 more
Precise measurements of stellar parameters are required in order to develop our theoretical understanding of stellar structure. These measurements enable errors and uncertainties to be quantified in theoretical models and constrain the physical interpretation of observed phenomena, such as the inflated radii of low-mass stars.