Search Publications
On the Observability of Individual Population III Stars and Their Stellar-mass Black Hole Accretion Disks through Cluster Caustic Transits
Kelly, Patrick L.; Driver, Simon P.; Windhorst, Rogier A. +8 more
We summarize panchromatic Extragalactic Background Light data to place upper limits on the integrated near-infrared surface brightness (SB) that may come from Population III stars and possible accretion disks around their stellar-mass black holes (BHs) in the epoch of First Light, broadly taken from z ≃ 7-17. Theoretical predictions and recent nea…
Riding the kinematic waves in the Milky Way disk with Gaia
Figueras, F.; Antoja, T.; Ramos, P.
Context. Gaia DR2 has delivered full-sky six-dimensional measurements for millions of stars, and the quest to understand the dynamics of our Galaxy has entered a new phase.
Aims: Our aim is to reveal and characterise the kinematic substructure of the different Galactic neighbourhoods, to form a picture of their spatial evolution that can be u…
The Diversity of Kilonova Emission in Short Gamma-Ray Bursts
Covino, S.; Lyman, J. D.; Fruchter, A. S. +10 more
The historic first joint detection of both gravitational-wave and electromagnetic emission from a binary neutron star merger cemented the association between short gamma-ray bursts (SGRBs) and compact object mergers, as well as providing a well-sampled multi-wavelength light curve of a radioactive kilonova (KN) for the first time. Here, we compare…
Discovery of new retrograde substructures: the shards of ω Centauri?
Myeong, G. C.; Evans, N. W.; Belokurov, V. +2 more
We use the Sloan Digital Sky Survey (SDSS)-Gaia catalogue to search for substructure in the stellar halo. The sample comprises 62 133 halo stars with full phase space coordinates and extends out to heliocentric distances of ∼10 kpc. As actions are conserved under slow changes of the potential, they permit identification of groups of stars with a c…
Composition and Chemistry of the Neutral Atmosphere of Venus
Marcq, Emmanuel; Vandaele, Ann Carine; Parkinson, Christopher D. +1 more
This paper deals with the composition and chemical processes occurring in the neutral atmosphere of Venus. Since the last synthesis, observers as well as modellers have emphasised the spatial and temporal variability of minor species, going beyond a static and uniform picture that may have prevailed in the past. The outline of this paper acknowled…
Gravitationally lensed quasars in Gaia - II. Discovery of 24 lensed quasars
McMahon, Richard G.; Auger, Matthew W.; Lemon, Cameron A. +1 more
We report the discovery, spectroscopic confirmation, and preliminary characterization of 24 gravitationally lensed quasars identified using Gaia observations. Candidates were selected in the Pan-STARRS footprint with quasar-like WISE colours or as photometric quasars from Sloan Digital Sky Survey (SDSS), requiring either multiple detections in Gai…
Testing General Relativity with the Reflection Spectrum of the Supermassive Black Hole in 1H0707-495
Cao, Zheng; Bambi, Cosimo; Nampalliwar, Sourabh +2 more
Recently, we have extended the x-ray reflection model relxill to test the spacetime metric in the strong gravitational field of astrophysical black holes. In the present Letter, we employ this extended model to analyze XMM-Newton, NuSTAR, and Swift data of the supermassive black hole in 1H0707-495 and test deviations from a Kerr metric parametrize…
The 6 September 2017 X-Class Solar Flares and Their Impacts on the Ionosphere, GNSS, and HF Radio Wave Propagation
Yasyukevich, Y.; Astafyeva, E.; Padokhin, A. +3 more
On 6 September 2017, the Sun emitted two significant solar flares (SFs). The first SF, classified X2.2, peaked at 09:10 UT. The second one, X9.3, which is the most intensive SF in the current solar cycle, peaked at 12:02 UT and was accompanied by solar radio emission. In this work, we study ionospheric response to the two X-class SFs and their imp…
CANDELSz7: a large spectroscopic survey of CANDELS galaxies in the reionization epoch
Maiolino, R.; Dickinson, M.; Finkelstein, S. L. +15 more
We present the results of CANDELSz7, a European Southern Observatory (ESO) Large Program aimed at spectroscopically confirming a homogeneous sample of z ≃ 6 and z ≃ 7 star forming galaxies. The candidates were selected in the GOODS-South, UDS, and COSMOS fields using the official CANDELS catalogs based on H160-band detections. Standard …
Water Reservoirs in Small Planetary Bodies: Meteorites, Asteroids, and Comets
Altwegg, Kathrin; Alexander, Conel M. O'D.; McKeegan, Kevin D.
Asteroids and comets are the remnants of the swarm of planetesimals from which the planets ultimately formed, and they retain records of processes that operated prior to and during planet formation. They are also likely the sources of most of the water and other volatiles accreted by Earth. In this review, we discuss the nature and probable origin…