Search Publications
CLASH: Extending Galaxy Strong Lensing to Small Physical Scales with Distant Sources Highly Magnified by Galaxy Cluster Members
Infante, L.; Zheng, W.; Molino, A. +35 more
We present a complex strong lensing system in which a double source is imaged five times by two early-type galaxies. We take advantage in this target of the extraordinary multi-band photometric data set obtained as part of the Cluster Lensing And Supernova survey with Hubble (CLASH) program, complemented by the spectroscopic measurements of the VL…
Circumnuclear Molecular Gas in Megamaser Disk Galaxies NGC 4388 and NGC 1194
Greene, Jenny E.; van de Ven, Glenn; Seth, Anil +3 more
We explore the warm molecular and ionized gas in the centers of two megamaser disk galaxies using K-band spectroscopy. Our ultimate goal is to determine how gas is funneled onto the accretion disk, here traced by megamaser spots on sub-parsec scales. We present NIR IFU data with a resolution of ~50 pc for two galaxies: NGC 4388 with VLT/SINFONI an…
ALMA Observations of the Host Galaxy of GRB 090423 at z = 8.23: Deep Limits on Obscured Star Formation 630 Million Years after the Big Bang
Berger, E.; Chary, R. -R.; Chornock, R. +7 more
We present rest-frame far-infrared (FIR) and optical observations of the host galaxy of GRB 090423 at z = 8.23 from the Atacama Large Millimeter Array (ALMA) and the Spitzer Space Telescope, respectively. The host remains undetected to 3σ limits of F ν(222 GHz) <~ 33 µJy and F ν(3.6 µm) <~ 81 nJy. The FIR li…
Suzaku Observation of IRAS 00521-7054, a Peculiar Type-II AGN with a Very Broad Feature at 6 keV
Paltani, S.; Ricci, C.; Terashima, Y. +3 more
IRAS 00521-7054 is the first Seyfert 2 in which the presence of an extremely large Fe Kα line has been claimed. We report here on the analysis of a 100 ks Suzaku observation of the source. We confirm the existence of a very strong excess over the power-law X-ray continuum at E ~ 6 keV (EW ~= 800 eV), extending down to ~4.5 keV, and found that the …
The Extreme Ultraviolet Deficit and Magnetically Arrested Accretion in Radio-loud Quasars
Punsly, Brian
The Hubble Space Telescope composite quasar spectra presented in Telfer et al. show a significant deficit of emission in the extreme ultraviolet for the radio-loud component of the quasar population (RLQs) compared to the radio-quiet component of the quasar population. The composite quasar continuum emission between 1100 Å and ~580 Å is generally …
First Extragalactic Detection of Submillimeter CH Rotational Lines from the Herschel Space Observatory
Wilson, Christine D.; Glenn, Jason; Spinoglio, Luigi +5 more
We present the first extragalactic detections of several CH rotational transitions in the far-infrared in four nearby galaxies, NGC 1068, Arp 220, M82, and NGC 253, using the Herschel Space Observatory. The CH lines in all four galaxies are a factor of 2-4 brighter than the adjacent HCN and HCO+ J = 6-5 lines (also detected in the same …
Super-Eddington Accretion in the Ultraluminous X-Ray Source NGC 1313 X-2: An Ephemeral Feast
Weng, Shan-Shan; Zhao, Hai-Hui; Zhang, Shuang-Nan
We investigate the X-ray spectrum, variability, and the surrounding ionized bubble of NGC 1313 X-2 to explore the physics of super-Eddington accretion. Beyond the Eddington luminosity, the accretion disk of NGC 1313 X-2 is truncated at a large radius (~50 times the innermost stable circular orbit), and displays the similar evolution track with bot…
Hubble Space Telescope Observations of the Nucleus of Comet C/2012 S1 (ISON)
Weaver, Harold A.; Toth, Imre; Lamy, Philippe L.
We report on the analysis of several sequences of broadband visible images of comet C/2012 S1 (ISON) taken with the Wide Field Camera 3 of the Hubble Space Telescope on 2013 April 10, May 8, October 9, and November 1 in an attempt to detect and characterize its nucleus. Whereas the overwhelming coma precluded the detection of the nucleus in the fi…
Solar Energetic Particle Events in Different Types of Solar Wind
Vourlidas, A.; Kahler, S. W.
We examine statistically some properties of 96 20 MeV gradual solar energetic proton (SEP) events as a function of three different types of solar wind (SW) as classified by Richardson and Cane. Gradual SEP (E > 10 MeV) events are produced in shocks driven by fast (V >~ 900 km s-1) and wide (W > 60°) coronal mass ejections (CMEs…
XMM-Newton and Chandra Observations of the Ejecta-dominated Mixed-morphology Galactic Supernova Remnant G352.7-0.1
Kargaltsev, Oleg; Pannuti, Thomas G.; Napier, Jared P. +1 more
We present a spatial and spectral X-ray analysis of the Galactic supernova remnant (SNR) G352.7-0.1 using archival data from observations made with the XMM-Newton X-ray Observatory and the Chandra X-ray Observatory. Prior X-ray observations of this SNR had revealed a thermal center-filled morphology that contrasts with a shell-like radio morpholog…