Search Publications
Evolution of Galaxy Stellar Mass Functions, Mass Densities, and Mass-to-light Ratios from z ~ 7 to z ~ 4
Franx, Marijn; Labbé, Ivo; Kriek, Mariska +3 more
We derive stellar masses from spectral energy distribution fitting to rest-frame optical and UV fluxes for 401 star-forming galaxies at z ~ 4, 5, and 6 from Hubble-WFC3/IR camera observations of the Early Release Science field combined with the deep GOODS-S Spitzer/IRAC data (and include a previously published z ~ 7 sample). A mass-luminosity rela…
Observations of Arp 220 Using Herschel-SPIRE: An Unprecedented View of the Molecular Gas in an Extreme Star Formation Environment
Clements, D. L.; Wilson, Christine D.; Baes, Maarten +20 more
We present Herschel Spectral and Photometric Imaging Receiver Fourier Transform Spectrometer (Herschel SPIRE-FTS) observations of Arp 220, a nearby ultra-luminous infrared galaxy. The FTS provides continuous spectral coverage from 190 to 670 µm, a wavelength region that is either very difficult to observe or completely inaccessible from the …
Evidence for a Massive Neutron Star from a Radial-velocity Study of the Companion to the Black-widow Pulsar PSR B1957+20
Kulkarni, S. R.; van Kerkwijk, M. H.; Breton, R. P.
The most massive neutron stars constrain the behavior of ultra-dense matter, with larger masses possible only for increasingly stiff equations of state. Here, we present evidence that the black-widow pulsar, PSR B1957+20, has a high mass. We took spectra of its strongly irradiated companion and found an observed radial-velocity amplitude of K
Galaxy-wide Shocks in Late-merger Stage Luminous Infrared Galaxies
Kewley, L. J.; Dopita, M. A.; Rich, J. A.
We present an integral field spectroscopic study of two nearby luminous infrared galaxies (LIRGs), IC 1623 and NGC 3256, which exhibit evidence of widespread shock excitation induced by ongoing merger activity. We show the importance of carefully separating excitation due to shocks versus excitation by H II regions and the usefulness of integral f…
Dissecting Photometric Redshift for Active Galactic Nucleus Using XMM- and Chandra-COSMOS Samples
Kneib, J. -P.; Aussel, H.; Le Floc'h, E. +62 more
In this paper, we release accurate photometric redshifts for 1692 counterparts to Chandra sources in the central square degree of the Cosmic Evolution Survey (COSMOS) field. The availability of a large training set of spectroscopic redshifts that extends to faint magnitudes enabled photometric redshifts comparable to the highest quality results pr…
The Interstellar Medium in Distant Star-forming Galaxies: Turbulent Pressure, Fragmentation, and Cloud Scaling Relations in a Dense Gas Disk at z = 2.3
Thomson, A. P.; Ivison, R. J.; Smail, Ian +7 more
We have used the Institut de Radioastronomie Millimétrique (IRAM) Plateau de Bure Interferometer and the Expanded Very Large Array to obtain a high-resolution map of the CO(6-5) and CO(1-0) emission in the lensed, star-forming galaxy SMM J2135-0102 at z = 2.32. The kinematics of the gas are well described by a model of a rotationally supported dis…
The Tucana/Horologium, Columba, AB Doradus, and Argus Associations: New Members and Dusty Debris Disks
Zuckerman, B.; Song, Inseok; Bessell, M. S. +1 more
We propose 35 star systems within ~70 pc of Earth as newly identified members of nearby young stellar kinematic groups; these identifications include the first A- and late-B-type members of the AB Doradus moving group and field Argus Association. All but one of the 35 systems contain a bright solar- or earlier-type star that should make an excelle…
Line Derived Infrared Extinction toward the Galactic Center
Lutz, D.; Genzel, R.; Gillessen, S. +7 more
We derive the extinction curve toward the Galactic center (GC) from 1 to 19 µm. We use hydrogen emission lines of the minispiral observed by ISO-SWS and SINFONI. The extinction-free flux reference is the 2 cm continuum emission observed by the Very Large Array. Toward the inner 14'' × 20'', we find an extinction of A 2.166 µm
The Majority of Compact Massive Galaxies at z ~ 2 are Disk Dominated
Bell, Eric F.; Koekemoer, Anton M.; van der Wel, Arjen +6 more
We investigate the stellar structure of massive, quiescent galaxies at z ~ 2, based on Hubble Space Telescope/WFC3 imaging from the Early Release Science program. Our sample of 14 galaxies has stellar masses of M * > 1010.8 M sun and photometric redshifts of 1.5 < z < 2.5. In agreement with previous work, …
Evidence for Ultra-fast Outflows in Radio-quiet Active Galactic Nuclei. II. Detailed Photoionization Modeling of Fe K-shell Absorption Lines
Cappi, M.; Dadina, M.; Tombesi, F. +3 more
X-ray absorption line spectroscopy has recently shown evidence for previously unknown Ultra-fast Outflows (UFOs) in radio-quiet active galactic nuclei (AGNs). These have been detected essentially through blueshifted Fe XXV/XXVI K-shell transitions. In the previous paper of this series we defined UFOs as those highly ionized absorbers with an outfl…