Search Publications
A Map of Dust Reddening to 4.5 kpc from Pan-STARRS1
Price, P. A.; Rix, H. -W.; Chambers, K. C. +17 more
We present a map of the dust reddening to 4.5 kpc derived from Pan-STARRS1 stellar photometry. The map covers almost the entire sky north of declination -30° at a resolution of 7'-14', and is based on the estimated distances and reddenings to more than 500 million stars. The technique is designed to map dust in the Galactic plane, where many other…
Isochrones for Old (>5 Gyr) Stars and Stellar Populations. I. Models for -2.4 <= [Fe/H] <=+0.6, 0.25 <= Y <= 0.33, and -0.4 <= [α/Fe] <=+0.4
Edvardsson, Bengt; VandenBerg, Don A.; Ferguson, Jason W. +1 more
Canonical grids of stellar evolutionary sequences have been computed for the helium mass-fraction abundances Y = 0.25, 0.29, and 0.33, and for iron abundances that vary from -2.4 to +0.4 (in 0.2 dex increments) when [α/Fe] =+0.4, or for the ranges -2.0 <= [Fe/H] <=+0.6, -1.8 <= [Fe/H] <=+0.6 when [α/Fe] =0.0 and -0.4, respectively. The…
NuSTAR Discovery of a Luminosity Dependent Cyclotron Line Energy in Vela X-1
Hailey, Charles J.; Fürst, Felix; Pottschmidt, Katja +13 more
We present NuSTAR observations of Vela X-1, a persistent, yet highly variable, neutron star high-mass X-ray binary (HMXB). Two observations were taken at similar orbital phases but separated by nearly a year. They show very different 3-79 keV flux levels as well as strong variability during each observation, covering almost one order of magnitude …
Three-fluid, Three-dimensional Magnetohydrodynamic Solar Wind Model with Eddy Viscosity and Turbulent Resistivity
Matthaeus, William H.; Goldstein, Melvyn L.; Usmanov, Arcadi V.
We have developed a three-fluid, three-dimensional magnetohydrodynamic solar wind model that incorporates turbulence transport, eddy viscosity, turbulent resistivity, and turbulent heating. The solar wind plasma is described as a system of co-moving solar wind protons, electrons, and interstellar pickup protons, with separate energy equations for …
Structures of Interplanetary Magnetic Flux Ropes and Comparison with Their Solar Sources
Qiu, Jiong; Hu, Qiang; Dasgupta, B. +2 more
Whether a magnetic flux rope is pre-existing or formed in situ in the Sun's atmosphere, there is little doubt that magnetic reconnection is essential to release the flux rope during its ejection. During this process, the question remains: how does magnetic reconnection change the flux-rope structure? In this work, we continue with the original stu…
Modeling the Formation of Globular Cluster Systems in the Virgo Cluster
Li, Hui; Gnedin, Oleg Y.
The mass distribution and chemical composition of globular cluster (GC) systems preserve fossil record of the early stages of galaxy formation. The observed distribution of GC colors within massive early-type galaxies in the ACS Virgo Cluster Survey (ACSVCS) reveals a multi-modal shape, which likely corresponds to a multi-modal metallicity distrib…
The NuSTAR View of Nearby Compton-thick Active Galactic Nuclei: The Cases of NGC 424, NGC 1320, and IC 2560
Harrison, F. A.; Stern, D.; Zhang, W. W. +25 more
We present X-ray spectral analyses for three Seyfert 2 active galactic nuclei (AGNs), NGC 424, NGC 1320, and IC 2560, observed by NuSTAR in the 3-79 keV band. The high quality hard X-ray spectra allow detailed modeling of the Compton reflection component for the first time in these sources. Using quasi-simultaneous NuSTAR and Swift/XRT data, as we…
CARMA Large Area Star Formation Survey: Observational Analysis of Filaments in the Serpens South Molecular Cloud
Fernández-López, M.; Rosolowsky, E.; Shirley, Y. L. +15 more
We present the N2H+ (J = 1 → 0) map of the Serpens South molecular cloud obtained as part of the CARMA Large Area Star Formation Survey. The observations cover 250 arcmin2 and fully sample structures from 3000 AU to 3 pc with a velocity resolution of 0.16 km s-1, and they can be used to constrain the ori…
An Infrared-luminous Merger with Two Bipolar Molecular Outflows: ALMA and SMA Observations of NGC 3256
Aalto, Susanne; Sakamoto, Kazushi; Combes, Francoise +2 more
We report Atacama Large Millimeter/sub-millimeter Array and Submillimeter Array observations of the infrared-luminous merger NGC 3256, the most luminous galaxy within z = 0.01. Both of the two merger nuclei separated by 5'' (0.8 kpc) have a molecular gas concentration, a nuclear disk, with Σmol > 103 M ⊙ pc…
Accretion onto Planetary Mass Companions of Low-mass Young Stars
Herczeg, Gregory J.; Metchev, Stanimir; Zhou, Yifan +2 more
Measurements of accretion rates onto planetary mass objects may distinguish between different planet formation mechanisms, which predict different accretion histories. In this Letter, we use Hubble Space Telescope (HST)/WFC3 UVIS optical photometry to measure accretion rates onto three accreting objects, GSC 06214-00210 b, GQ Lup b, and DH Tau b, …