Search Publications
A Comparison of Rest-frame Ultraviolet and Optical Emission-line Diagnostics in the Lensed Galaxy SDSS J1723+3411 at Redshift z = 1.3293
Rigby, J. R.; Momcheva, Ivelina; Brammer, Gabriel +13 more
For the extremely bright lensed galaxy SDSS J1723+3411 at z = 1.3293, we analyze spatially integrated MMT, Keck, and Hubble Space Telescope spectra that fully cover the rest-frame wavelength range of 1400-7200 Å. We also analyze near-IR spectra from Gemini that cover Hα for a portion of the lensed arc. We report fluxes for 42 detected emission lin…
A Characterization of the Circumstellar Gas of WD 1124-293 Using Cloudy
Dufour, Patrick; Steele, Amy; Debes, John +2 more
Between 30% and 50% of white dwarfs (WDs) show heavy elements in their atmospheres. This pollution is thought to arise from the accretion of planetesimals perturbed by outer planet(s) to within the WD's tidal disruption radius. A small fraction of these WDs show either emission or absorption from circumstellar (C-S) gas. The abundances of metals i…
Potential Black Hole Seeding of the Spiral Galaxy NGC 4424 via an Infalling Star Cluster
Soria, Roberto; Ciambur, Bogdan C.; Swartz, Douglas A. +2 more
Galaxies can grow through their mutual gravitational attraction and subsequent union. While orbiting a regular high-surface-brightness galaxy, the body of a low-mass galaxy can be stripped away. However, the stellar heart of the infalling galaxy, if represented by a tightly bound nuclear star cluster, is more resilient. From archival Hubble Space …
The Core Mass Function in the Orion Nebula Cluster Region: What Determines the Final Stellar Masses?
Sanhueza, Patricio; Mairs, Steve; Nakamura, Fumitaka +29 more
Applying dendrogram analysis to the CARMA-NRO C18O (J = 1-0) data having an angular resolution of ∼8″, we identified 692 dense cores in the Orion Nebula Cluster region. Using this core sample, we compare the core and initial stellar mass functions in the same area to quantify the step from cores to stars. About 22% of the identified cor…
Spatially Resolved RGS Analysis of Kepler's Supernova Remnant
Katsuda, Satoru; Sato, Toshiki; Hughes, John P. +4 more
The distribution and kinematics of the circumstellar medium (CSM) around a supernova remnant (SNR) tell us useful information about the explosion of its natal supernova (SN). Kepler's SNR, the remnant of SN 1604, is widely regarded to be of Type Ia origin. Its shock is moving through a dense, asymmetric CSM. The presence of this dense gas suggests…
TESS Observations of Be Stars: General Characteristics and the Impulsive Magnetic Rotator Model
Balona, Luis A.; Ozuyar, Dogus
Evidence of rotational light modulation in 30%-40% of normal B stars is presented, suggesting the presence of starspots and photospheric activity. On this basis, we propose that mass loss in Be stars is a result of magnetic reconnection coupled with rapid but not necessarily near-critical rotation. The ejected matter is trapped at two diametricall…
ALMA and IRIS Observations of the Solar Chromosphere. II. Structure and Dynamics of Chromospheric Plages
Martínez-Sykora, Juan; De Pontieu, Bart; Chintzoglou, Georgios +7 more
We propose and employ a novel empirical method for determining chromospheric plage regions, which seems to better isolate a plage from its surrounding regions than other methods commonly used. We caution that isolating a plage from its immediate surroundings must be done with care in order to successfully mitigate statistical biases that, for inst…
Compton-Thick AGN in the NuSTAR ERA VII. A joint NuSTAR, Chandra, and XMM-Newton Analysis of Two Nearby, Heavily Obscured Sources
Vignali, C.; Gilli, R.; Ajello, M. +11 more
We present the joint Chandra, XMM-Newton, and NuSTAR analysis of two nearby Seyfert galaxies, NGC 3081 and ESO 565-G019. These are the only two having Chandra data in a larger sample of 10 low-redshift (z ≤ 0.05), candidates Compton-thick (CT) Active Galactic Nuclei selected in the 15-150 keV band with Swift-BAT that were still lacking NuSTAR data…
Beyond Simple AGN Unification with Chandra-observed 3CRR Sources at 0.5 < z < 1
Azadi, Mojegan; Wilkes, Belinda J.; McDowell, Jonathan C. +14 more
Low-frequency radio selection finds radio-bright galaxies regardless of the amount of obscuration by gas and dust. We report Chandra observations of a complete 178 MHz-selected, and so orientation-unbiased, sample of 44 0.5 < z < 1 3CRR sources. The sample is comprised of quasars and narrow-line radio galaxies (NLRGs) with similar radio lumi…
The VLA Frontier Field Survey: A Comparison of the Radio and UV/Optical Size of 0.3 ≲ z ≲ 3 Star-forming Galaxies
Smail, I.; Dickinson, M.; Jiménez-Andrade, E. F. +6 more
To investigate the growth history of galaxies, we measure the rest-frame radio, ultraviolet (UV), and optical sizes of 98 radio-selected, star-forming galaxies (SFGs) distributed over 0.3 ≲ z ≲ 3 with a median stellar mass of $\mathrm{log}({M}_{\star }/{M}_{\odot })\approx 10.4$ . We compare the size of galaxy stellar disks, traced by rest-frame o…