Search Publications
Panchromatic Hubble Andromeda Treasury. XVI. Star Cluster Formation Efficiency and the Clustered Fraction of Young Stars
Bell, Eric F.; Dolphin, Andrew E.; Skillman, Evan D. +10 more
We use the Panchromatic Hubble Andromeda Treasury survey data set to perform spatially resolved measurements of star cluster formation efficiency (Γ), the fraction of stellar mass formed in long-lived star clusters. We use robust star formation history and cluster parameter constraints, obtained through color-magnitude diagram analysis of resolved…
X-Ray Detected Active Galactic Nuclei in Dwarf Galaxies at 0 < z < 1
Silverman, J. D.; Hickox, R. C.; Greene, J. E. +6 more
We present a sample of accreting supermassive black holes (SMBHs) in dwarf galaxies at z\lt 1. We identify dwarf galaxies in the NEWFIRM Medium Band Survey with stellar masses of {M}\star \lt 3× {10}9 {M}⊙ that have spectroscopic redshifts from the DEEP2 survey and lie within the region covered by deep (flux limit…
Magnetar-like Activity from the Central Compact Object in the SNR RCW103
Rea, N.; Esposito, P.; De Luca, A. +4 more
The 6.67 hr periodicity and the variable X-ray flux of the central compact object (CCO) at the center of the supernova remnant RCW 103, named 1E 161348-5055, have been always difficult to interpret within the standard scenarios of an isolated neutron star (NS) or a binary system. On 2016 June 22, the Burst Alert Telescope (BAT) on board Swift dete…
Morphology and Molecular Gas Fractions of Local Luminous Infrared Galaxies as a Function of Infrared Luminosity and Merger Stage
Sanders, D. B.; Kim, D. -C.; Mirabel, I. F. +8 more
We present a new, detailed analysis of the morphologies and molecular gas fractions (MGFs) for a complete sample of 65 local luminous infrared galaxies from Great Observatories All-Sky Luminous Infrared Galaxies (LIRG) Survey using high resolution I-band images from The Hubble Space Telescope, the University of Hawaii 2.2 m Telescope and the Pan-S…
Simulations of the Mg II k and Ca II 8542 lines from an Alfvén Wave-heated Flare Chromosphere
Kerr, Graham S.; Fletcher, Lyndsay.; Russell, Alexander J. B. +1 more
We use radiation hydrodynamic simulations to examine two models of solar flare chromospheric heating: Alfvén wave dissipation and electron beam collisional losses. Both mechanisms are capable of strong chromospheric heating, and we show that the distinctive atmospheric evolution in the mid-to-upper chromosphere results in Mg II k-line emission tha…
Global Sausage Oscillation of Solar Flare Loops Detected by the Interface Region Imaging Spectrograph
Reeves, Katharine K.; Chen, Bin; He, Jiansen +4 more
An observation from the Interface Region Imaging Spectrograph reveals coherent oscillations in the loops of an M1.6 flare on 2015 March 12. Both the intensity and Doppler shift of Fe xxi 1354.08 Å show clear oscillations with a period of ∼25 s. Remarkably similar oscillations were also detected in the soft X-ray flux recorded by the Geostationary …
A Keck Adaptive Optics Survey of a Representative Sample of Gravitationally Lensed Star-forming Galaxies: High Spatial Resolution Studies of Kinematics and Metallicity Gradients
Richard, Johan; Stark, Daniel P.; Ellis, Richard S. +4 more
We discuss spatially resolved emission line spectroscopy secured for a total sample of 15 gravitationally lensed star-forming galaxies at a mean redshift of z≃ 2 based on Keck laser-assisted adaptive optics observations undertaken with the recently improved OSIRIS integral field unit (IFU) spectrograph. By exploiting gravitationally lensed sources…
The Bursty Star Formation Histories of Low-mass Galaxies at 0.4 < z < 1 Revealed by Star Formation Rates Measured From Hβ and FUV
Barro, Guillermo; Pérez-González, Pablo G.; Bell, Eric F. +17 more
We investigate the burstiness of star formation histories (SFHs) of galaxies at 0.4 < z < 1 by using the ratio of star formation rates (SFRs) measured from Hβ and FUV (1500 Å) (Hβ-to-FUV ratio). Our sample contains 164 galaxies down to stellar mass (M *) of 108.5 M ⊙ in the CANDELS GOODS-N region, where Team …
Star Formation and AGN Activity in Galaxy Clusters from z=1-2: a Multi-Wavelength Analysis Featuring Herschel/PACS
Dey, Arjun; Cybulski, Ryan; Alberts, Stacey +11 more
We present a detailed, multi-wavelength study of star formation (SF) and active galactic nucleus (AGN) activity in 11 near-infrared (IR) selected, spectroscopically confirmed massive (≳1014 M ⊙) galaxy clusters at 1 < z < 1.75. Using new deep Herschel/PACS imaging, we characterize the optical to far-IR spectral energy d…
The BOSS Emission-line Lens Survey. IV. Smooth Lens Models for the BELLS GALLERY Sample
Brownstein, Joel R.; Marques-Chaves, Rui; Oguri, Masamune +9 more
We present Hubble Space Telescope F606W-band imaging observations of 21 galaxy-Lyα emitter lens candidates in the Baryon Oscillation Spectroscopic Survey Emission-Line Lens Survey (BELLS) for the GALaxy-Lyα EmitteR sYstems (BELLS GALLERY) survey. Seventeen systems are confirmed to be definite lenses with unambiguous evidence of multiple imaging. T…