Search Publications
High-mass X-ray binaries in nearby metal-poor galaxies: on the contribution to nebular He II emission
Charlot, Stéphane; Stark, Daniel P.; Mulchaey, John S. +4 more
Despite significant progress both observationally and theoretically, the origin of high-ionization nebular He II emission in galaxies dominated by stellar photoionization remains unclear. Accretion-powered radiation from high-mass X-ray binaries (HMXBs) is still one of the leading proposed explanations for the missing He+-ionizing photo…
The Sloan Digital Sky Survey Reverberation Mapping Project: The Hβ Radius-Luminosity Relation
Trump, Jonathan R.; Brandt, W. N.; Shen, Yue +8 more
Results from a few decades of reverberation mapping (RM) studies have revealed a correlation between the radius of the broad-line emitting region (BLR) and the continuum luminosity of active galactic nuclei. This "radius-luminosity" relation enables survey-scale black hole mass estimates across cosmic time, using relatively inexpensive single-epoc…
Continuum-fitting the X-Ray Spectra of Tidal Disruption Events
Wen, Sixiang; Jonker, Peter G.; Stone, Nicholas C. +2 more
We develop a new model for X-ray emission from tidal disruption events (TDEs), applying stationary general relativistic "slim disk" accretion solutions to supermassive black holes (SMBHs) and then ray-tracing the photon trajectories from the image plane to the disk surface, including gravitational redshift, Doppler, and lensing effects self-consis…
Galactic halo size in the light of recent AMS-02 data
Maurin, D.; Salati, P.; Génolini, Y. +6 more
Context. The vertical diffusive halo size of the Galaxy, L, is a key parameter for dark matter indirect searches. It can be better determined thanks to recent AMS-02 data.
Aims: We set constraints on L from Be/B and 10Be/Be data, and we performed a consistency check with positron data. We detail the dependence of Be/B and 10
Age dating of an early Milky Way merger via asteroseismology of the naked-eye star ν Indi
Smalley, Barry; Chaplin, William J.; Davies, Guy R. +82 more
Over the course of its history, the Milky Way has ingested multiple smaller satellite galaxies1. Although these accreted stellar populations can be forensically identified as kinematically distinct structures within the Galaxy, it is difficult in general to date precisely the age at which any one merger occurred. Recent results have rev…
Long Baseline Observations of the HD 100546 Protoplanetary Disk with ALMA
Dong, Ruobing; Pérez, Sebastián; Casassus, Simon +9 more
Using the Atacama Large Millimeter/submillimeter Array, we observed the young Herbig star HD 100546, host to a prominent disk with a deep, wide gap in the dust. The high-resolution 1.3 mm continuum observation reveals fine radial and azimuthal substructures in the form of a complex maze of ridges and trenches sculpting a dust ring. The 12
The Hawaii Infrared Parallax Program. IV. A Comprehensive Parallax Survey of L0-T8 Dwarfs with UKIRT
Magnier, Eugene A.; Dupuy, Trent J.; Liu, Michael C. +1 more
We present parallaxes, proper motions, and J-band photometry for 348 L and T dwarfs measured using the wide-field near-infrared camera WFCAM on the United Kingdom Infrared Telescope. This is the largest single batch of infrared parallaxes for brown dwarfs to date. Our parallaxes have a median uncertainty of 3.5 mas, similar to most previous ground…
A Sub-Neptune-sized Planet Transiting the M2.5 Dwarf G 9-40: Validation with the Habitable-zone Planet Finder
Endl, Michael; Mahadevan, Suvrath; Terrien, Ryan +32 more
We validate the discovery of a 2-Earth-radii sub-Neptune-sized planet around the nearby high-proper-motion M2.5 dwarf G 9-40 (EPIC 212048748), using high-precision, near-infrared (NIR) radial velocity (RV) observations with the Habitable-zone Planet Finder (HPF), precision diffuser-assisted ground-based photometry with a custom narrowband photomet…
AGN-driven outflows and the AGN feedback efficiency in young radio galaxies
Morganti, R.; Holt, J.; Tadhunter, C. +2 more
Active galactic nuclei (AGN) feedback operated by the expansion of radio jets can play a crucial role in driving gaseous outflows on galaxy scales. Galaxies hosting young radio AGN, whose jets are in the first phases of expansion through the surrounding interstellar medium (ISM), are the ideal targets to probe the energetic significance of this me…
Is there Na I in the atmosphere of HD 209458b?. Effect of the centre-to-limb variation and Rossiter-McLaughlin effect in transmission spectroscopy studies
Alonso-Floriano, F. J.; Sánchez-López, A.; López-Puertas, M. +22 more
HD 209458b was the first transiting planet discovered, and the first for which an atmosphere, in particular Na I, was detected. With time, it has become one of the most frequently studied planets, with a large diversity of atmospheric studies using low- and high-resolution spectroscopy. Here, we present transit spectroscopy observations of HD 2094…