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Gaia Proper Motions and Orbits of the Ultra-faint Milky Way Satellites
Simon, Joshua D.
The second data release from the Gaia mission (DR2) provides a comprehensive and unprecedented picture of the motions of astronomical sources in the plane of the sky, extending from the solar neighborhood to the outer reaches of the Milky Way. I present proper-motion measurements based on Gaia DR2 for 17 ultra-faint dwarf galaxies within 100 kpc o…
Measuring Dark Energy Properties with Photometrically Classified Pan-STARRS Supernovae. II. Cosmological Parameters
Berger, E.; Kirshner, R. P.; Rest, A. +25 more
We use 1169 Pan-STARRS supernovae (SNe) and 195 low-z (z < 0.1) SNe Ia to measure cosmological parameters. Though most Pan-STARRS SNe lack spectroscopic classifications, in a previous paper we demonstrated that photometrically classified SNe can be used to infer unbiased cosmological parameters by using a Bayesian methodology that marginalizes …
Deep Learning Based Solar Flare Forecasting Model. I. Results for Line-of-sight Magnetograms
Xu, Long; Huang, Xin; Wang, Huaning +3 more
Solar flares originate from the release of the energy stored in the magnetic field of solar active regions, the triggering mechanism for these flares, however, remains unknown. For this reason, the conventional solar flare forecast is essentially based on the statistic relationship between solar flares and measures extracted from observational dat…
The Opacity of the Intergalactic Medium Measured along Quasar Sightlines at z ∼ 6
Hennawi, Joseph F.; Davies, Frederick B.; Eilers, Anna-Christina
We publicly release a new sample of 34 medium resolution quasar spectra at 5.77 ≤ z em ≤ 6.54 observed with the Echellette Spectrograph and Imager on the Keck telescope. This quasar sample represents an ideal laboratory to study the intergalactic medium (IGM) during the end stages of the epoch of reionization, and constrain the timing a…
Light Curves of Hydrogen-poor Superluminous Supernovae from the Palomar Transient Factory
Cenko, S. B.; Sollerman, J.; Spyromilio, J. +24 more
We investigate the light-curve properties of a sample of 26 spectroscopically confirmed hydrogen-poor superluminous supernovae (SLSNe-I) in the Palomar Transient Factory survey. These events are brighter than SNe Ib/c and SNe Ic-BL, on average, by about 4 and 2 mag, respectively. The peak absolute magnitudes of SLSNe-I in rest-frame g band span -2…
Measuring Radial Orbit Migration in the Galactic Disk
Ting, Yuan-Sen; Hogg, David W.; Rix, Hans-Walter +2 more
We develop and apply a model to quantify the global efficiency of radial orbit migration among stars in the Milky Way disk. This model parameterizes the possible star formation and enrichment histories and radial birth profiles, and combines them with a migration model that relates present-day orbital radii to birth radii through a Gaussian probab…
Evidence for Pulsar-like Emission Components in the Broadband ULX Sample
Harrison, F. A.; Stern, D.; Fabian, A. C. +7 more
We present broadband X-ray analyses of a sample of bright ultraluminous X-ray sources (ULX) with the goal of investigating the spectral similarity of this population to the known ULX pulsars, M82 X-2, NGC 7793 P13, and NGC 5907 ULX. We perform a phase-resolved analysis of the broadband XMM-Newton+NuSTAR data set of NGC 5907 ULX, finding that the p…
“Super-deblended” Dust Emission in Galaxies. I. The GOODS-North Catalog and the Cosmic Star Formation Rate Density out to Redshift 6
Dickinson, Mark; Inami, Hanae; Daddi, Emanuele +10 more
We present a new technique to measure multi-wavelength “super-deblended” photometry from highly confused images, which we apply to Herschel and ground-based far-infrared (FIR) and (sub-)millimeter (mm) data in the northern field of the Great Observatories Origins Deep Survey. There are two key novelties. First, starting with a large database of de…
The Disk Substructures at High Angular Resolution Project (DSHARP). IX. A High-definition Study of the HD 163296 Planet-forming Disk
Wilner, David J.; Andrews, Sean M.; Guzmán, Viviana V. +11 more
The Atacama Large Millimeter/submillimeter Array observations of protoplanetary disks acquired by the Disk Substructure at High Angular Resolution Project resolve the dust and gas emission on angular scales as small as 3 astronomical units, offering an unprecedented detailed view of the environment where planets form. In this Letter, we present an…
The Missing Satellites of the Magellanic Clouds? Gaia Proper Motions of the Recently Discovered Ultra-faint Galaxies
van der Marel, Roeland P.; Navarro, Julio F.; Sacchi, Elena +7 more
According to LCDM theory, hierarchical evolution occurs on all mass scales, implying that satellites of the Milky Way should also have companions. The recent discovery of ultra-faint dwarf galaxy candidates in close proximity to the Magellanic Clouds provides an opportunity to test this theory. We present proper motion (PM) measurements for 13 of …