Search Publications
Broken into Pieces: ATLAS and Aliqa Uma as One Single Stream
Lewis, Geraint F.; Hattori, Kohei; Erkal, Denis +18 more
We present the first spectroscopic measurements of the ATLAS and Aliqa Uma streams from the Southern Stellar Stream Spectroscopic Survey (S5), in combination with the photometric data from the Dark Energy Survey and astrometric data from Gaia. From the coherence of spectroscopic members in radial velocity and proper motion, we find that…
Spiral Arms and a Massive Dust Disk with Non-Keplerian Kinematics: Possible Evidence for Gravitational Instability in the Disk of Elias 2-27
Lodato, G.; Pinte, C.; Testi, L. +16 more
To determine the origin of the spiral structure observed in the dust continuum emission of Elias 2-27 we analyze multiwavelength continuum ALMA data with a resolution of ~0"2 (~23 au) at 0.89, 1.3, and 3.3 mm. We also study the kinematics of the disk with 13CO and C18O ALMA observations in the J = 3-2 transition. The spiral a…
A "Quick Look" at All-sky Galactic Archeology with TESS: 158,000 Oscillating Red Giants from the MIT Quick-look Pipeline
Huber, Daniel; Sharma, Sanjib; Stello, Dennis +6 more
We present the first near all-sky yield of oscillating red giants from the prime mission data of NASA's Transiting Exoplanet Survey Satellite (TESS). We apply machine learning toward long-cadence TESS photometry from the first data release by the MIT Quick-look Pipeline to automatically detect the presence of red giant oscillations in frequency po…
Milky Way Mid-Infrared Spitzer Spectroscopic Extinction Curves: Continuum and Silicate Features
Gordon, Karl D.; Hines, Dean C.; Bouwman, Jeroen +7 more
We measured the mid-infrared (MIR) extinction using Spitzer photometry and spectroscopy (3.6-37 µm) for a sample of Milky Way sight lines (mostly) having measured ultraviolet extinction curves. We used the pair method to determine the MIR extinction that we then fit with a power law for the continuum and modified Drude profiles for the silic…
CGM2 I: The Extent of the Circumgalactic Medium Traced by Neutral Hydrogen
Tripp, Todd M.; Prochaska, J. Xavier; Tejos, Nicolas +8 more
We present initial results from the Cosmic Origins Spectrograph (COS) and Gemini Mapping the Circumgalactic Medium (CGMCGM ≡ CGM2) survey. The CGM2 survey consists of 1689 galaxies, all with high-quality Gemini-GMOS spectra, within 1 Mpc of 22 z ≲ 1 quasars, all with a signal-to-noise ratio of ∼10 Hubble Space Telescope/COS G…
UV Spectral Slopes at z = 6-9 in the Hubble Frontier Fields: Lack of Evidence for Unusual or Population III Stellar Populations
Conselice, Christopher J.; Bhatawdekar, Rachana
We present new measurements of the UV spectral slope β for galaxies at z = 6-9 in the Frontier Field cluster MACS J0416.1-2403 and its parallel field to an unprecedented level of low stellar mass. We fit synthetic stellar population models to the observed spectral energy distribution and calculate β by fitting a power law to the best-fit spectrum.…
A Local Baseline of the Black Hole Mass Scaling Relations for Active Galaxies. IV. Correlations Between MBH and Host Galaxy σ, Stellar Mass, and Luminosity
Treu, Tommaso; Auger, Matthew W.; Birrer, Simon +6 more
The tight correlations between the mass of supermassive black holes (MBH) and their host-galaxy properties have been of great interest to the astrophysical community, but a clear understanding of their origin and fundamental drivers still eludes us. The local relations for active galaxies are interesting in their own right and form the …
Revealing the Accretion Physics of Supermassive Black Holes at Redshift z ∼ 7 with Chandra and Infrared Observations
Hennawi, Joseph F.; Fan, Xiaohui; Walter, Fabian +14 more
X-ray emission from quasars has been detected up to redshift z = 7.5, although only limited to a few objects at z > 6.5. In this work, we present new Chandra observations of five z > 6.5 quasars. By combining with archival Chandra observations of six additional z > 6.5 quasars, we perform a systematic analysis on the X-ray properties of t…
Accretion Geometry in the Hard State of the Black Hole X-Ray Binary MAXI J1820+070
Zdziarski, Andrzej A.; Szanecki, Michał; Niedźwiecki, Andrzej +2 more
We study X-ray spectra from the outburst rise of the accreting black hole binary MAXI J1820+070. We find that models having the disk inclinations within those of either the binary or the jet imply significant changes of the accretion disk inner radius during the luminous part of the hard spectral state, with that radius changing from >100 to ∼1…
Black Hole Mass Measurements of Radio Galaxies NGC 315 and NGC 4261 Using ALMA CO Observations
Ho, Luis C.; Barth, Aaron J.; Buote, David A. +6 more
We present Atacama Large Millimeter/submillimeter Array (ALMA) Cycle 5 and Cycle 6 observations of CO (2-1) and CO (3-2) emission at 0"2-0"3 resolution in two radio-bright, brightest group/cluster early-type galaxies, NGC 315 and NGC 4261. The data resolve CO emission that extends within their black hole (BH) spheres of influence (rg), …