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A New Low Magnetic Field Magnetar: The 2011 Outburst of Swift J1822.3-1606
Campana, S.; Tiengo, A.; Götz, D. +20 more
We report on the long-term X-ray monitoring with Swift, RXTE, Suzaku, Chandra, and XMM-Newton of the outburst of the newly discovered magnetar Swift J1822.3-1606 (SGR 1822-1606), from the first observations soon after the detection of the short X-ray bursts which led to its discovery, through the first stages of its outburst decay (covering the ti…
Discovery of a Dissociative Galaxy Cluster Merger with Large Physical Separation
Bradač, Maruša; Hughes, John P.; Dawson, William A. +10 more
We present DLSCL J0916.2+2951 (z = 0.53), a newly discovered major cluster merger in which the collisional cluster gas has become dissociated from the collisionless galaxies and dark matter (DM). We identified the cluster using optical and weak-lensing observations as part of the Deep Lens Survey. Our follow-up observations with Keck, Subaru, Hubb…
The Bright End of the Ultraviolet Luminosity Function at z ~ 8: New Constraints from CANDELS Data in GOODS-South
Trenti, M.; Oesch, P. A.; Carollo, C. M. +7 more
We present new z ~ 8 galaxy candidates from a search over ~95 arcmin2 of WFC3/IR data, tripling the previous search area for bright z ~ 8 galaxies. Our analysis uses newly acquired WFC3/IR imaging data from the CANDELS Multi-Cycle Treasury program over the GOODS-South field. These new data are combined with existing deep optical Advance…
Vertical Atmospheric Structure in a Variable Brown Dwarf: Pressure-dependent Phase Shifts in Simultaneous Hubble Space Telescope-Spitzer Light Curves
Burrows, Adam; Showman, Adam P.; Apai, Dániel +6 more
Heterogeneous clouds or temperature perturbations in rotating brown dwarfs produce variability in the observed flux. We report time-resolved simultaneous observations of the variable T6.5 brown dwarf 2MASS J22282889-431026 over the wavelength ranges 1.1-1.7 µm and broadband 4.5 µm. Spectroscopic observations were taken with Wide Field …
Keck Spectroscopy of Faint 3 < z < 7 Lyman Break Galaxies. III. The Mean Ultraviolet Spectrum at z ~= 4
Stark, Daniel P.; Ellis, Richard S.; Jones, Tucker
We present and discuss the mean rest-frame ultraviolet spectrum for a sample of 81 Lyman break galaxies (LBGs) selected to be B-band dropouts at z ~= 4. The sample is mostly drawn from our ongoing Keck/DEIMOS survey in the GOODS fields and augmented with archival Very Large Telescope data. In general, we find similar spectroscopic trends to those …
Blind Detections of CO J = 1-0 in 11 H-ATLAS Galaxies at z = 2.1-3.5 with the GBT/Zpectrometer
Ivison, R. J.; Frayer, D. T.; Clements, D. L. +29 more
We report measurements of the carbon monoxide ground state rotational transition (12C16O J = 1-0) with the Zpectrometer ultrawideband spectrometer on the 100 m diameter Green Bank Telescope. The sample comprises 11 galaxies with redshifts between z = 2.1 and 3.5 from a total sample of 24 targets identified by Herschel-ATLAS p…
The Primeval Populations of the Ultra-faint Dwarf Galaxies
Ferguson, Henry C.; Brown, Thomas M.; Geha, Marla +9 more
We present new constraints on the star formation histories of the ultra-faint dwarf (UFD) galaxies, using deep photometry obtained with the Hubble Space Telescope (HST). A galaxy class recently discovered in the Sloan Digital Sky Survey, the UFDs appear to be an extension of the classical dwarf spheroidals to low luminosities, offering a new front…
A Swift Look at SN 2011fe: The Earliest Ultraviolet Observations of a Type Ia Supernova
Gronwall, Caryl; Milne, Peter; Kuin, Paul +8 more
We present the earliest ultraviolet (UV) observations of the bright Type Ia supernova SN 2011fe/PTF11kly in the nearby galaxy M101 at a distance of only 6.4 Mpc. It was discovered shortly after explosion by the Palomar Transient Factory and first observed by Swift/UVOT about a day after explosion. The early UV light is well defined, with ~20 data …
Sigmoidal Active Region on the Sun: Comparison of a Magnetohydrodynamical Simulation and a Nonlinear Force-free Field Model
Aulanier, G.; Pariat, E.; Savcheva, A. +2 more
In this paper we show that when accurate nonlinear force-free field (NLFFF) models are analyzed together with high-resolution magnetohydrodynamic (MHD) simulations, we can determine the physical causes for the coronal mass ejection (CME) eruption on 2007 February 12. We compare the geometrical and topological properties of the three-dimensional ma…
Modeling Dust and Starlight in Galaxies Observed by Spitzer and Herschel: NGC 628 and NGC 6946
Helou, G.; Roussel, H.; Murphy, E. J. +26 more
We characterize the dust in NGC 628 and NGC 6946, two nearby spiral galaxies in the KINGFISH sample. With data from 3.6 µm to 500 µm, dust models are strongly constrained. Using the Draine & Li dust model (amorphous silicate and carbonaceous grains), for each pixel in each galaxy we estimate (1) dust mass surface density, (2) dust …