Search Publications
A thirty-four billion solar mass black hole in SMSS J2157-3602, the most luminous known quasar
Fan, Xiaohui; Wolf, Christian; Bian, Fuyan +3 more
From near-infrared spectroscopic measurements of the Mg II emission line doublet, we estimate the black hole (BH) mass of the quasar, SMSS J215728.21-360215.1, as being (3.4 ± 0.6) × 1010 M⊙ and refine the redshift of the quasar to be z = 4.692. SMSS J2157 is the most luminous known quasar, with a 3000 Å luminosity of (4.7 ± …
Polyphase Mid-Latitude Glaciation on Mars: Chronology of the Formation of Superposed Glacier-Like Forms from Crater-Count Dating
Hepburn, A. J.; Hubbard, B.; Ng, F. S. L. +2 more
Reconstructing Mars's glacial history informs understanding of its physical environment and past climate. The known distribution of viscous flow features (VFFs) containing water ice suggests that its mid-latitudes were glaciated during the Late Amazonian period (the last several hundred million years). The identification of a subgroup of VFFs—call…
Exploring Effects on Magnifications due to Line-of-Sight Galaxies in the Hubble Frontier Fields
Keeton, Charles R.; Raney, Catie A.; Brennan, Sean
Cluster lensing has become an important tool in the search for high redshift galaxies through its ability to magnify sources. In order to determine the intrinsic properties of these galaxies, lensing mass models must be constructed to determine the magnification of the images. These models are traditionally two-dimensional, focusing on the mass wi…
Surface Brightness Evolution of Galaxies in the CANDELS GOODS Fields up to z ∼ 6: High-z Galaxies Are Unique or Remain Undetected
Conselice, C. J.; Duncan, K.; Spitler, L. R. +1 more
We investigate the rest-frame ultraviolet (UV, λ ∼ 2000 Å) surface brightness (SB) evolution of galaxies up to z ∼ 6 using a variety of deep Hubble Space Telescope (HST) imaging. UV SB is a measure of the density of emission from mostly young stars and correlates with an unknown combination of star formation rate, initial mass function, cold gas m…
Constraining planet formation around 6-8 M⊙ stars
Hermes, J. J.; Gänsicke, Boris T.; Kennedy, Grant M. +4 more
Identifying planets around O-type and B-type stars is inherently difficult; the most massive known planet host has a mass of only about $3\, \mathrm{M}_{\odot }$ . However, planetary systems which survive the transformation of their host stars into white dwarfs can be detected via photospheric trace metals, circumstellar dusty and gaseous discs, a…
First detection of two superoutbursts during the rebrightening phase of a WZ Sge-type dwarf nova: TCP J21040470+4631129
Ruiz, Javier; Nogami, Daisaku; Tamura, Motohide +51 more
We report on photometric and spectroscopic observations and analysis of the 2019 superoutburst of TCP J21040470+4631129. This object showed a 9 mag superoutburst with early superhumps and ordinary superhumps, which are the features of WZ Sge-type dwarf novae. Five rebrightenings were observed after the main superoutburst. The spectra during the po…
The High-mass Protostellar Population of a Massive Infrared Dark Cloud
Zhang, Yichen; Tan, Jonathan C.; Lim, Wanggi +3 more
We conduct a census of the high-mass protostellar population of the ∼70,000 M⊙ infrared dark cloud (IRDC) G028.37+00.07, identifying 35 sources based on their 70 µm emission, as reported in the Herschel Hi-GAL catalog of Molinari et al. We perform aperture photometry to construct spectral energy distributions, which are then fit w…
Short-term variability and mass loss in Be stars. V. Space photometry and ground-based spectroscopy of γ Cas
Handler, G.; Weiss, A.; Rivinius, Th. +9 more
Context. Be stars are physically complex systems that continue to challenge theory to understand their rapid rotation, complex variability, and decretion disks. γ Cassiopeiae (γ Cas) is one such star but is even more curious because of its unexplained hard thermal X-ray emission.
Aims: We aim to examine the optical variability of γ Cas and th…
A fresh look at the RR Lyrae population in the Draco dwarf spheroidal galaxy with Gaia
Garofalo, Alessia; Clementini, Gisella; Muraveva, Tatiana +1 more
We present a catalogue of 285 RR Lyrae stars (RRLs) in the Draco dwarf spheroidal (dSph) galaxy, obtained by combining data from a number of different surveys including the Data Release 2 (DR2) of the European Space Agency cornerstone mission Gaia. We have determined individual distances to the RRLs in our sample using for the first time a Gaia G-…
Gemini Near-Infrared Field Spectrograph Observations of the Seyfert 2 Galaxy Mrk 3: Feeding and Feedback on Galactic and Nuclear Scales
Kraemer, S. B.; Crenshaw, D. M.; Storchi-Bergmann, T. +10 more
We explore the kinematics of the stars, ionized gas, and warm molecular gas in the Seyfert 2 galaxy Mrk 3 (UGC 3426) on nuclear and galactic scales with Gemini Near-Infrared Field Spectrograph observations, previous Hubble Space Telescope data, and new long-slit spectra from the Apache Point Observatory (APO) 3.5 m telescope. The APO spectra are c…