Search Publications
The Radial Acceleration Relation in CLASH Galaxy Clusters
Donahue, Megan; Umetsu, Keiichi; Chiu, I. -Non +2 more
The radial acceleration relation (RAR) in galaxies describes a tight empirical scaling law between the total acceleration ${g}_{\mathrm{tot}}(r)={{GM}}_{\mathrm{tot}}(\lt r)/{r}^{2}$ observed in galaxies and that expected from their baryonic mass ${g}_{\mathrm{bar}}(r)={{GM}}_{\mathrm{bar}}(\lt r)/{r}^{2}$, with a characteristic acceleration scale…
Is π Men c’s Atmosphere Hydrogen-dominated? Insights from a Non-detection of H I Lyα Absorption
Rauer, H.; Gandolfi, D.; Fossati, L. +3 more
Constraining the composition of super-Earth-to-sub-Neptune-sized planets is a priority in order to understand the processes of planetary formation and evolution. π Men c represents a unique target for the atmospheric and compositional characterization of such planets because it is strongly irradiated and its bulk density is consistent with abundan…
The Splash without a Merger
Debattista, Victor P.; Amarante, João A. S.; Beraldo e Silva, Leandro +1 more
The Milky Way's progenitor experienced several merger events that left their imprints on the stellar halo, including the Gaia-Sausage/Enceladus. Recently, it has been proposed that this event perturbed the proto-disk and gave rise to a metal-rich ([Fe/H] > -1), low angular momentum (Vφ < 100 km s-1) stellar population. …
Diagnosing the Stellar Population and Tidal Structure of the Blanco 1 Star Cluster
Tang, Shih-Yun; Chen, W. P.; Zhang, Yu +2 more
We present the stellar population, using Gaia DR2 parallax, kinematics, and photometry, of the young (∼100 Myr), nearby (∼230 pc) open cluster, Blanco 1. A total of 644 member candidates are identified via the unsupervised machine learning method StarGO to find the clustering in the five-dimensional position and proper motion parameter (X, Y, Z, $…
Resolving the Soft X-Ray Ultrafast Outflow in PDS 456
Reeves, J. N.; Braito, V.; Nardini, E. +3 more
Past X-ray observations of the nearby luminous quasar PDS 456 (at z = 0.184) have revealed a wide-angle accretion disk wind with an outflow velocity of ∼-0.25c, as observed through observations of its blueshifted iron K-shell absorption line profile. Here we present three new XMM-Newton observations of PDS 456: one in 2018 September where the quas…
A Census of Sub-kiloparsec Resolution Metallicity Gradients in Star-forming Galaxies at Cosmic Noon from HST Slitless Spectroscopy
Teplitz, Harry I.; Schmidt, Kasper B.; Treu, Tommaso +12 more
We present the hitherto largest sample of gas-phase metallicity radial gradients measured at sub-kpc resolution in star-forming galaxies in the redshift range of z ∈ [1.2, 2.3]. These measurements are enabled by the synergy of slitless spectroscopy from the Hubble Space Telescope near-infrared channels and the lensing magnification from foreground…
Stellar Feedback and Resolved Stellar IFU Spectroscopy in the Nearby Spiral Galaxy NGC 300
Kruijssen, J. M. Diederik; Longmore, Steven N.; Chevance, Mélanie +7 more
We present MUSE integral field unit (IFU) observations of five individual H II regions in two giant star-forming complexes in the low-metallicity, nearby dwarf spiral galaxy NGC 300. In combination with high spatial resolution Hubble Space Telescope photometry, we demonstrate the extraction of stellar spectra and classification of individual stars…
Gamma-Ray Urgent Archiver for Novel Opportunities (GUANO): Swift/BAT Event Data Dumps on Demand to Enable Sensitive Subthreshold GRB Searches
Cenko, S. Bradley; Palmer, David M.; Barthelmy, Scott +3 more
We introduce a new capability of the Neil Gehrels Swift Observatory to provide event-level data from the Burst Alert Telescope (BAT) on demand in response to transients detected by other instruments. We show that the availability of these data can effectively increase the rate of detections and arcminute localizations of gamma-ray bursts (GRB) lik…
Galaxy Morphology Network: A Convolutional Neural Network Used to Study Morphology and Quenching in ∼100,000 SDSS and ∼20,000 CANDELS Galaxies
Schawinski, Kevin; Urry, C. Megan; Powell, Meredith C. +3 more
We examine morphology-separated color-mass diagrams to study the quenching of star formation in ∼100,000 (z ∼ 0) Sloan Digital Sky Survey (SDSS) and ∼20,000 (z ∼ 1) Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey (CANDELS) galaxies. To classify galaxies morphologically, we developed Galaxy Morphology Network (GAMORNET), a convolutio…
Detection of PAH Absorption and Determination of the Mid-infrared Diffuse Interstellar Extinction Curve from the Sight Line toward Cyg OB2-12
Draine, B. T.; Hensley, Brandon S.
The sight line toward the luminous blue hypergiant Cyg OB2-12 is widely used to study interstellar dust on account of its large extinction (AV ≃ 10 mag) and the fact that this extinction appears to be dominated by dust typical of the diffuse interstellar medium. We present a new analysis of archival Infrared Space Observatory Short Wave…