Search Publications
New constraints on interacting dark energy from cosmic chronometers
Nunes, Rafael C.; Pan, Supriya; Saridakis, Emmanuel N.
We use the latest compilation of observational Hubble parameter measurements estimated with the differential evolution of cosmic chronometers, in combination with the local value of the Hubble constant recently measured with 2.4% precision, to constrain the cosmological scenario where dark energy interacts directly with the dark matter sector. To …
Direct Detection of Lyman Continuum Escape from Local Starburst Galaxies with the Cosmic Origins Spectrograph
Hernandez, Svea; Leitherer, Claus; Oey, M. S. +1 more
We report on the detection of Lyman continuum radiation in two nearby starburst galaxies. Tol 0440-381, Tol 1247-232, and Mrk 54 were observed with the Cosmic Origins Spectrograph on board the Hubble Space Telescope. The three galaxies have radial velocities of ∼13,000 km s-1, permitting a ∼35 Å window on the restframe Lyman continuum s…
The Offset and Host Light Distributions of Long Gamma-Ray Bursts: A New View From HST Observations of Swift Bursts
Fong, Wen-fai; Berger, Edo; Blanchard, Peter K.
We present the results of an extensive Hubble Space Telescope imaging study of 105, mostly Swift, long-duration gamma-ray bursts (LGRBs) spanning 0.03≲ z≲ 9.4, which were localized using relative astrometry from ground- and space-based afterglow observations. We measure the distribution of LGRB offsets from their host centers and their relation to…
The Evolution of Star Formation Histories of Quiescent Galaxies
Barro, Guillermo; Bell, Eric F.; Ferguson, Henry C. +22 more
Although there has been much progress in understanding how galaxies evolve, we still do not understand how and when they stop forming stars and become quiescent. We address this by applying our galaxy spectral energy distribution models, which incorporate physically motivated star formation histories (SFHs) from cosmological simulations, to a samp…
Sub-kiloparsec ALMA Imaging of Compact Star-forming Galaxies at z ~ 2.5: Revealing the Formation of Dense Galactic Cores in the Progenitors of Compact Quiescent Galaxies
Rujopakarn, W.; Faber, S. M.; Guo, Y. +10 more
We present spatially resolved Atacama Large Millimeter/submillimeter Array (ALMA) 870 µm dust continuum maps of six massive, compact, dusty star-forming galaxies at z ∼ 2.5. These galaxies are selected for their small rest-frame optical sizes ({r}{{e,F160W}}∼ 1.6 kpc) and high stellar mass densities that suggest that they are dire…
The population of X-ray supernova remnants in the Large Magellanic Cloud
Pietsch, W.; Haberl, F.; Greiner, J. +11 more
Aims: We present a comprehensive X-ray study of the population of supernova remnants (SNRs) in the Large Magellanic Cloud (LMC). Using primarily XMM-Newton observations, we conduct a systematic spectral analysis of LMC SNRs to gain new insight into their evolution and the interplay with their host galaxy.
Methods: We combined all the arc…
The ALMA Spectroscopic Survey in the Hubble Ultra Deep Field: Continuum Number Counts, Resolved 1.2 mm Extragalactic Background, and Properties of the Faintest Dusty Star-forming Galaxies
Smail, I.; Magnelli, B.; Daddi, E. +31 more
We present an analysis of a deep (1σ = 13 µJy) cosmological 1.2 mm continuum map based on ASPECS, the ALMA Spectroscopic Survey in the Hubble Ultra Deep Field. In the 1 arcmin2 covered by ASPECS we detect nine sources at \gt 3.5σ significance at 1.2 mm. Our ALMA-selected sample has a median redshift of z=1.6+/- 0.4, with only one …
Estimating Distances from Parallaxes. II. Performance of Bayesian Distance Estimators on a Gaia-like Catalogue
Bailer-Jones, Coryn A. L.; Astraatmadja, Tri L.
Estimating a distance by inverting a parallax is only valid in the absence of noise. As most stars in the Gaia catalog will have non-negligible fractional parallax errors, we must treat distance estimation as a constrained inference problem. Here we investigate the performance of various priors for estimating distances, using a simulated Gaia cata…
LOFAR/H-ATLAS: a deep low-frequency survey of the Herschel-ATLAS North Galactic Pole field
Prandoni, I.; Brunetti, G.; White, G. J. +25 more
We present Low-Frequency Array (LOFAR) High-Band Array observations of the Herschel-ATLAS North Galactic Pole survey area. The survey we have carried out, consisting of four pointings covering around 142 deg2 of sky in the frequency range 126-173 MHz, does not provide uniform noise coverage but otherwise is representative of the quality…
A New Distortion Solution for NIRC2 on the Keck II Telescope
Ghez, A. M.; Anderson, J.; Lu, J. R. +3 more
We present a new geometric distortion model for the narrow-field mode of the near-infrared camera (NIRC2) fed by the adaptive optics system on the W. M. Keck II telescope. The adaptive optics system and NIRC2 camera were realigned on 2015 April 13. Observations of the crowded globular cluster, M53, were obtained before and after the realignment to…