Search Publications
Star Formation at z = 2.481 in the Lensed Galaxy SDSS J1110+6459: Star Formation Down to 30 pc Scales
Rigby, Jane R.; Florian, Michael; Whitaker, Katherine E. +7 more
We present measurements of the surface density of star formation, the star-forming clump luminosity function, and the clump size distribution function, for the lensed galaxy SGAS J111020.0+645950.8 at a redshift of z = 2.481. The physical size scales that we probe, radii r = 30-50 pc, are considerably smaller scales than have yet been studied at t…
Molecular Gas Dominated 50 kpc Ram Pressure Stripped Tail of the Coma Galaxy D100
Yoshida, Michitoshi; Combes, Françoise; Sun, Ming +6 more
We have discovered large amounts of molecular gas, as traced by CO emission, in the ram pressure stripped gas tail of the Coma cluster galaxy D100 (GMP 2910), out to large distances of about 50 kpc. D100 has a 60 kpc long, strikingly narrow tail, which is bright in X-rays and Hα. Our observations with the IRAM 30 m telescope reveal in total ∼ {10}…
GASP. III. JO36: A Case of Multiple Environmental Effects at Play?
Charlot, Stéphane; Fritz, Jacopo; Vulcani, Benedetta +12 more
The so-called jellyfish galaxies are objects exhibiting disturbed morphology, mostly in the form of tails of gas stripped from the main body of the galaxy. Several works have strongly suggested ram pressure stripping to be the mechanism driving this phenomenon. Here, we focus on one of these objects, drawn from a sample of optically selected jelly…
The Extent of Chemically Enriched Gas around Star-forming Dwarf Galaxies
Johnson, Sean D.; Chen, Hsiao-Wen; Mulchaey, John S. +2 more
Supernova driven winds are often invoked to remove chemically enriched gas from dwarf galaxies to match their low observed metallicities. In such shallow potential wells, outflows may produce massive amounts of enriched halo gas (circumgalactic medium, CGM) and pollute the intergalactic medium (IGM). Here, we present a survey of the CGM and IGM ar…
COS-burst: Observations of the Impact of Starburst-driven Winds on the Properties of the Circum-galactic Medium
Heckman, Timothy; Wild, Vivienne; Borthakur, Sanchayeeta +2 more
We report on observations made with the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope (HST) using background quasi-stellar objects to probe the circum-galactic medium (CGM) around 17 low-redshift galaxies that are undergoing or have recently undergone a strong starburst (the COS-Burst program). The sightlines extend out to roughl…
Does a Differentiated, Carbonate-rich, Rocky Object Pollute the White Dwarf SDSS J104341.53+085558.2?
Dufour, P.; Melis, Carl
We present spectroscopic observations of the dust- and gas-enshrouded, polluted, single white dwarf star SDSS J104341.53+085558.2 (hereafter SDSS J1043+0855). Hubble Space Telescope Cosmic Origins Spectrograph far-ultraviolet spectra combined with deep Keck HIRES optical spectroscopy reveal the elements C, O, Mg, Al, Si, P, S, Ca, Fe, and Ni and e…
Microlensing of Extremely Magnified Stars near Caustics of Galaxy Clusters
Miralda-Escudé, Jordi; Dai, Liang; Venumadhav, Tejaswi
Recent observations of lensed galaxies at cosmological distances have detected individual stars that are extremely magnified when crossing the caustics of lensing clusters. In idealized cluster lenses with smooth mass distributions, two images of a star of radius R approaching a caustic brighten as {t}-1/2 and reach a peak magnification…
Lensing Constraints on the Mass Profile Shape and the Splashback Radius of Galaxy Clusters
Umetsu, Keiichi; Diemer, Benedikt
The lensing signal around galaxy clusters can, in principle, be used to test detailed predictions for their average mass profile from numerical simulations. However, the intrinsic shape of the profiles can be smeared out when a sample that spans a wide range of cluster masses is averaged in physical length units. This effect especially conceals ra…
The Dragonfly Nearby Galaxies Survey. III. The Luminosity Function of the M101 Group
van Dokkum, Pieter; Abraham, Roberto; Danieli, Shany +4 more
We obtained follow-up HST observations of the seven low surface brightness galaxies discovered with the Dragonfly Telephoto Array in the field of the massive spiral galaxy M101. Out of the seven galaxies, only three were resolved into stars and are potentially associated with the M101 group at D = 7 Mpc. Based on HST ACS photometry in the broad F6…
Relations between the Sizes of Galaxies and Their Dark Matter Halos at Redshifts 0 < z < 3
Pérez-González, Pablo G.; Ferguson, Henry C.; van der Wel, Arjen +6 more
We derive relations between the effective radii R eff of galaxies and the virial radii R 200c of their dark matter halos over the redshift range 0 < z < 3. For galaxies, we use the measured sizes from deep images taken with Hubble Space Telescope for the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey; f…