Search Publications
The Intrinsic Scatter along the Main Sequence of Star-forming Galaxies at z ~ 0.7
Zheng, Xian Zhong; Guo, Kexin; Fu, Hai
A sample of 12,614 star-forming galaxies (SFGs) with stellar mass >109.5 M ⊙ between 0.6 < z < 0.8 from COSMOS is selected to study the intrinsic scatter of the correlation between star formation rate (SFR) and stellar mass. We derive SFR from ultraviolet (UV) and infrared (IR) luminosities. A stacking technique is a…
Ellerman Bombs—Evidence for Magnetic Reconnection in the Lower Solar Atmosphere
Doyle, J. G.; Madjarska, M. S.; Erdélyi, R. +4 more
The presence of photospheric magnetic reconnection has long been thought to give rise to short and impulsive events, such as Ellerman bombs (EBs) and Type II spicules. In this article, we combine high-resolution, high-cadence observations from the Interferometric BIdimensional Spectrometer and Rapid Oscillations in the Solar Atmosphere instruments…
Herschel/PACS Survey of Protoplanetary Disks in Taurus/Auriga—Observations of [O I] and [C II], and Far-infrared Continuum
Roberge, Aki; Duchêne, Gaspard; Dent, William R. F. +17 more
The Herschel Space Observatory was used to observe ~120 pre-main-sequence stars in Taurus as part of the GASPS Open Time Key project. Photodetector Array Camera and Spectrometer was used to measure the continuum as well as several gas tracers such as [O I] 63 µm, [O I] 145 µm, [C II] 158 µm, OH, H2O, and CO. The strong…
Detection of Propene in Titan's Stratosphere
Irwin, P. G. J.; Teanby, N. A.; Flasar, F. M. +9 more
The Voyager 1 flyby of Titan in 1980 gave a first glimpse of the chemical complexity of Titan's atmosphere, detecting many new molecules with the infrared interferometer spectrometer (IRIS). These included propane (C3H8) and propyne (CH3C2H), while the intermediate-sized C3H x hydr…
Hubble Space Telescope Absolute Proper Motions Of NGC 6681 (M70) and the Sagittarius Dwarf Spheroidal Galaxy
Dalessandro, E.; Anderson, J.; Massari, D. +4 more
We have measured absolute proper motions for the three populations intercepted in the direction of the Galactic globular cluster NGC 6681: the cluster itself, the Sagittarius dwarf spheroidal galaxy, and the field. For this, we used Hubble Space Telescope ACS/WFC and WFC3/UVIS optical imaging data separated by a temporal baseline of 5.464 yr. Five…
Massive and Newly Dead: Discovery of a Significant Population of Galaxies with High-velocity Dispersions and Strong Balmer Lines at z ~ 1.5 from Deep Keck Spectra and HST/WFC3 Imaging
Franx, Marijn; van Dokkum, Pieter; Bezanson, Rachel +2 more
We present deep Keck/LRIS spectroscopy and Hubble Space Telescope/WFC3 imaging in the rest-frame optical for a sample of eight galaxies at z ~ 1.5 with high photometrically determined stellar masses. The data are combined with five Very Large Telescope/X-Shooter spectra. We find that these 13 galaxies have high velocity dispersions, with a median …
Observational Quantification of the Energy Dissipated by Alfvén Waves in a Polar Coronal Hole: Evidence that Waves Drive the Fast Solar Wind
Hahn, M.; Savin, D. W.
We present a measurement of the energy carried and dissipated by Alfvén waves in a polar coronal hole. Alfvén waves have been proposed as the energy source that heats the corona and drives the solar wind. Previous work has shown that line widths decrease with height in coronal holes, which is a signature of wave damping, but have been unable to qu…
A Fast Flare and Direct Redshift Constraint in Far-ultraviolet Spectra of the Blazar S5 0716+714
Danforth, Charles W.; France, Kevin; Keeney, Brian A. +1 more
The BL Lacertae object S5 0716+714 is one of the most studied blazars on the sky due to its active variability and brightness in many bands, including very-high-energy gamma rays. We present here two serendipitous results from recent far-ultraviolet spectroscopic observations by the Cosmic Origins Spectrograph onboard the Hubble Space Telescope (H…
Weak Hard X-Ray Emission from Two Broad Absorption Line Quasars Observed with NuSTAR: Compton-thick Absorption or Intrinsic X-Ray Weakness?
Harrison, F. A.; Stern, D.; Zhang, W. W. +22 more
We present Nuclear Spectroscopic Telescope Array (NuSTAR) hard X-ray observations of two X-ray weak broad absorption line (BAL) quasars, PG 1004+130 (radio loud) and PG 1700+518 (radio quiet). Many BAL quasars appear X-ray weak, probably due to absorption by the shielding gas between the nucleus and the accretion-disk wind. The two targets are amo…
CANDELS Observations of the Environmental Dependence of the Color-Mass-Morphology Relation at z = 1.6
Papovich, Casey; Finkelstein, Steven L.; Bell, Eric F. +16 more
We study the environmental dependence of color, stellar mass, and morphology by comparing galaxies in a forming cluster to those in the field at z = 1.6 with Hubble Space Telescope near-infrared imaging in the CANDELS/UDS field. We quantify the morphology of the galaxies using the effective radius, r eff, and Sérsic index, n. In both th…