Search Publications
The Atacama Cosmology Telescope: The LABOCA/ACT Survey of Clusters at All Redshifts
Hilton, Matt; Sifón, Cristóbal; Bond, J. Richard +24 more
We present a multi-wavelength analysis of 11 Sunyaev-Zel’dovich effect (SZE)-selected galaxy clusters (10 with new data) from the Atacama Cosmology Telescope (ACT) southern survey. We have obtained new imaging from the Large APEX Bolometer Camera (345 GHz; LABOCA) on the Atacama Pathfinder EXperiment (APEX) telescope, the Australia Telescope Compa…
RCS2 J232727.6-020437: An Efficient Cosmic Telescope at z=0.6986
Sharon, K.; Schrabback, T.; Hoag, A. +13 more
We present a detailed gravitational lens model of the galaxy cluster RCS2 J232727.6-020437. Due to cosmological dimming of cluster members and intra-cluster light, its high redshift (z = 0.6986) makes it ideal for studying high-redshift background galaxies. Using new Advanced Camera for Surveys and WFC3/IR Hubble Space Telescope data, we identify …
Rethinking a Mysterious Molecular Cloud
Imara, N.
I present high-resolution column density maps of two molecular clouds (MCs) having strikingly different star formation rates. To better understand the unusual, massive G216-2.5, an MC with no massive star formation, the distribution of its molecular gas is compared to that of the Rosette MC. Far-infrared data from Herschel are used to derive N(H
Updated 24 µm Period-Luminosity Relation Derived from Galactic Cepheids
Ngeow, Chow-Choong; Kanbur, Shashi M.; Bhardwaj, Anupam +2 more
In this work, we updated the catalog of Galactic Cepheids with 24 µm photometry by cross-matching the positions of known Galactic Cepheids to the recently released MIPSGAL point source catalog. We have added 36 new sources featuring MIPSGAL photometry in our analysis, thus increasing the existing sample to 65. Six different sources of compil…
Spectral Imaging of Galaxy Clusters with Planck
Rasia, E.; Bourdin, H.; Mazzotta, P.
The Sunyaev-Zeldovich (SZ) effect is a promising tool for detecting the presence of hot gas out to the galaxy cluster peripheries. We developed a spectral imaging algorithm dedicated to the SZ observations of nearby galaxy clusters with Planck, with the aim of revealing gas density anisotropies related to the filamentary accretion of materials, or…
A Coordinated X-Ray and Optical Campaign of the Nearest Massive Eclipsing Binary, δ Orionis Aa. I. Overview of the X-Ray Spectrum
Gull, T. R.; Corcoran, M. F.; Owocki, S. P. +22 more
We present an overview of four deep phase-constrained Chandra HETGS X-ray observations of δ Ori A. Delta Ori A is actually a triple system that includes the nearest massive eclipsing spectroscopic binary, δ Ori Aa, the only such object that can be observed with little phase-smearing with the Chandra gratings. Since the fainter star, δ Ori Aa2, has…
NGC 1266: Characterization of the Nuclear Molecular Gas in an Unusual SB0 Galaxy
Glenn, J.; Maloney, P. R.; Rangwala, N. +1 more
With a substantial nuclear molecular gas reservoir and broad, high-velocity CO molecular line wings previously interpreted as an outflow, NGC 1266 is a rare SB0 galaxy. Previous analyses of interferometry, spectrally resolved low-J CO emission lines, and unresolved high-J emission lines have established basic properties of the molecular gas and th…
Relative Abundance Measurements in Plumes and Interplumes
Hahn, M.; Savin, D. W.; Guennou, C.
We present measurements of relative elemental abundances in plumes and interplumes. Plumes are bright, narrow structures in coronal holes that extend along open magnetic field lines far out into the corona. Previous work has found that in some coronal structures the abundances of elements with a low first ionization potential (FIP) <10 eV are e…
Disentangling Overlapping Astronomical Sources Using Spatial and Spectral Information
van Dyk, David A.; Kashyap, Vinay L.; Jones, David E.
We present a powerful new algorithm that combines both spatial information (event locations and the point-spread function) and spectral information (photon energies) to separate photons from overlapping sources. We use Bayesian statistical methods to simultaneously infer the number of overlapping sources, to probabilistically separate the photons …
The Role of Bulge Formation in the Homogenization of Stellar Populations at z~2 as revealed by Internal Color Dispersion in CANDELS
Giavalisco, M.; Papovich, C.; Koekemoer, A. M. +13 more
We use data from the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey to study how the spatial variation in the stellar populations of galaxies relates to the formation of galaxies at 1.5\lt z\lt 3.5. We use the internal color dispersion (ICD), measured between the rest-frame UV and optical bands, which is sensitive to age (and dust …