Search Publications
Galaxies of the z ∼ 2 Universe. I. Grism-selected Rest-frame Optical Emission-line Galaxies
Yang, Guang; Schneider, Donald P.; Gronwall, Caryl +6 more
Euclid, the Wide Field Infrared Survey Telescope, and the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) will make emission-line selected galaxies the largest observed constituent in the z > 1 universe. However, we only have a limited understanding of the physical properties of galaxies selected via their Lyα or rest-frame optical emiss…
Angular Sizes, Radii, and Effective Temperatures of B-type Stars from Optical Interferometry with the CHARA Array
Gies, Douglas R.; Schaefer, Gail H.; Huber, Daniel +2 more
We present interferometric observations of 25 spectral type-B stars that were made with the Precision Astronomical Visible Observations and the CLassic Interferometry with Multiple Baselines beam combiners at the Center for High Angular Resolution Astronomy Array (CHARA). The observations provide the angular sizes of these stars with an average er…
Line Profiles of the Calcium I Resonance Line in Cool Metal-polluted White Dwarfs
Dufour, P.; Allard, N. F.; Blouin, S. +2 more
Metal-polluted white dwarfs (DZ stars) are characterized by a helium-rich atmosphere contaminated by heavy elements traces originating from accreted rocky planetesimals. As a detailed spectroscopic analysis of those objects can reveal the composition of the accreted debris, there is a great interest in developing accurate DZ atmosphere models. How…
Moving Groups as the Origin of the Vertical Phase Space Spiral in the Solar Neighborhood
Pérez-Villegas, Angeles; Barros, Douglas A.; Michtchenko, Tatiana A. +1 more
Using Gaia data release 2 (DR2), we analyzed the distribution of stars in the close vicinity of the Sun in the full 3D position-velocity space. We have found no evidence of incomplete phase mixing in the vertical direction of the disk, which could have originated from external events. We show that the vertical phase-space spiral Z-V z …
2 mm GISMO Observations of the Galactic Center. I. Dust Emission
Morris, Mark R.; Staguhn, Johannes; Gonzalez-Quiles, Junellie +5 more
The central molecular zone, covering the inner ∼1° of the Galactic plane has been mapped at 2 mm using the Goddard-IRAM Superconducting 2-Millimeter Observer (GISMO) bolometric camera on the 30 m IRAM telescope. The 21″ resolution maps show abundant emission from cold molecular clouds, from star-forming regions, and from one of the Galactic center…
Neutron Stars and Black Holes in the Small Magellanic Cloud: The SMC NuSTAR Legacy Survey
Haberl, F.; Lehmer, B. D.; Hornschemeier, A. E. +18 more
We present a source catalog from the first deep hard X-ray (E > 10 keV) survey of the Small Magellanic Cloud (SMC), the Nuclear Spectroscopic Telescope Array (NuSTAR) Legacy Survey of the SMC. We observed three fields, for a total exposure time of 1 Ms, along the bar of this nearby star-forming galaxy. Fields were chosen for their young stellar…
Evidence of New Magnetic Transitions in Late-type Dwarfs from Gaia DR2
Spada, Federico; Distefano, Elisa; Lanzafame, Alessandro C. +1 more
The second Gaia data release contains the identification of 147,535 low-mass (≲ 1.4 {M}⊙ ) rotational modulation variable candidates on (or close to) the main sequence, together with their rotation period and modulation amplitude. The richness, the period and amplitude range, and the photometric precision of this sample make it possible…
Thermal Emission and Magnetic Beaming in the Radio and X-Ray Mode-switching PSR B0943+10
Mereghetti, Sandro; Turolla, Roberto; Potekhin, Alexander Y. +3 more
PSR B0943+10 is a mode-switching radio pulsar characterized by two emission modes with different radio and X-ray properties. Previous studies, based on simple combinations of blackbody and power-law models, showed that its X-ray flux can be decomposed in a pulsed thermal plus an unpulsed nonthermal components. However, if PSR B0943+10 is a nearly …
XMM-Newton RGS Spectroscopy of the M31 Bulge. I. Evidence for a Past AGN Half a Million Years Ago
Wang, Q. Daniel; Li, Zhiyuan; Foster, Adam R. +3 more
Existing analysis based on spectra from the Reflection Grating Spectrometer (RGS) on board XMM-Newton already shows that the G-ratio of the O VII Heα triplet in the inner bulge of M31 is too high to be consistent with a pure optically thin thermal plasma in collisional ionization equilibrium (CIE). Different processes that may affect properties of…
SOFIA FORCAST Photometry of 12 Extended Green Objects in the Milky Way
Hunter, T. R.; Cyganowski, C. J.; Friesen, R. K. +2 more
Massive young stellar objects (MYSOs) are known to undergo an evolutionary phase in which high mass accretion rates drive strong outflows. A class of objects believed to trace this phase accurately is the Galactic Legacy Infrared Midplane Survey Extraordinaire (GLIMPSE) Extended Green Object (EGO) sample, so named for the presence of extended 4.5 …