Search Publications
Velocity dispersions of clusters in the Dark Energy Survey Y3 redMaPPer catalogue
Smith, M.; Lidman, C.; Davis, T. M. +97 more
We measure the velocity dispersions of clusters of galaxies selected by the red-sequence Matched-filter Probabilistic Percolation (redMaPPer) algorithm in the first three years of data from the Dark Energy Survey (DES), allowing us to probe cluster selection and richness estimation, λ, in light of cluster dynamics. Our sample consists of 126 clust…
A low-eccentricity migration pathway for a 13-h-period Earth analogue in a four-planet system
Trifonov, Trifon; Hellier, Coel; Latham, David W. +47 more
It is commonly accepted that exoplanets with orbital periods shorter than one day, also known as ultra-short-period (USP) planets, formed further out within their natal protoplanetary disks before migrating to their current-day orbits via dynamical interactions. One of the most accepted theories suggests a violent scenario involving high-eccentric…
New Variable Hot Subdwarf Stars Identified from Anomalous Gaia Flux Errors, Observed by TESS, and Classified via Fourier Diagnostics
Hermes, J. J.; Lopez, Isaac D.; Kupfer, Thomas +7 more
Hot subdwarf stars are mostly stripped red giants that can exhibit photometric variations due to stellar pulsations, eclipses, the reflection effect, ellipsoidal modulation, and Doppler beaming. Detailed studies of their light curves help constrain stellar parameters through asteroseismological analyses or binary light-curve modeling and generally…
Bridging Optical and Far-infrared Emission-line Diagrams of Galaxies from Local to the Epoch of Reionization: Characteristic High [O III] 88 µm/SFR at z > 6
Harikane, Yuichi; Inoue, Akio K.; Hashimoto, Takuya +3 more
We present photoionization modeling of galaxy populations at z ∼ 0, 2, and >6 to bridge optical and far-infrared (FIR) emission-line diagrams. We collect galaxies with measurements of optical and/or FIR ([O III] 88 µm and [C II] 158 µm) emission-line fluxes and plot them on the [O III]λ5007/Hβ-[N II]λ6585/Hα (BPT) and L([O III]…
On the Neutron Star/Black Hole Mass Gap and Black Hole Searches
Shao, Yong
Mass distribution of black holes in low-mass X-ray binaries previously suggested the existence of a ~2-5 M ⊙ mass gap between the most massive neutron stars and the least massive black holes, while some recent evidence appears to support that this mass gap is being populated. Whether there is a mass gap or not can potentially shed light…
Binary parameters from astrometric and spectroscopic errors - candidate hierarchical triples and massive dark companions in Gaia DR3
Belokurov, Vasily; Evans, N. Wyn; Andrew, Shion +2 more
We show how astrometric and spectroscopic errors introduced by an unresolved binary system can be combined to give estimates of the binary period and mass ratio. This can be performed analytically if we assume we see one or more full orbits over our observational baseline, or numerically for all other cases. We apply this method to Gaia DR3 data, …
Modeling the 2020 November 29 solar energetic particle event using EUHFORIA and iPATH models
Li, Gang; Poedts, Stefaan; Ding, Zheyi +1 more
Aims: We present the implementation of a coupling between EUropean Heliospheric FORcasting Information Asset (EUHFORIA) and improved Particle Acceleration and Transport in the Heliosphere (iPATH) models. In this work, we simulate the widespread solar energetic particle (SEP) event of 2020 November 29 and compare the simulated time-intensity p…
BASS. XXIII. A New Mid-infrared Diagnostic for Absorption in Active Galactic Nuclei
Ricci, Claudio; Stern, Daniel; Trakhtenbrot, Benny +15 more
In this study, we use the Swift/BAT AGN sample, which has received extensive multiwavelength follow-up analysis as a result of the BAT AGN Spectroscopic Survey, to develop a diagnostic for nuclear obscuration by examining the relationship between the line-of-sight column densities (N H), the 2–10 keV to 12 µm luminosity ratio, and…
A search for stellar structures around nine outer halo globular clusters in the Milky Way
Mackey, Dougal; Da Costa, Gary S.; Zhang, Shumeng
We use deep imaging from the Dark Energy Camera to explore the peripheral regions of nine globular clusters in the outer halo of the Milky Way. Apart from Whiting 1 and NGC 7492, which are projected against the Sagittarius stream, we see no evidence for adjacent stellar populations to indicate any of these clusters is associated with coherent tida…
Global Three-Dimensional Draping of Magnetic Field Lines in Earth's Magnetosheath From In-Situ Spacecraft Measurements
Lavraud, B.; Génot, V.; Jeandet, A. +4 more
Magnetic field draping occurs when the magnetic field lines frozen in a plasma flow wrap around a body or plasma environment. The draping of the interplanetary magnetic field (IMF) around the Earth's magnetosphere has been confirmed in the early days of space exploration. However, its global and three-dimensional structure is known from modeling o…