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Evidence for Water in the Rocky Debris of a Disrupted Extrasolar Minor Planet
Gänsicke, B. T.; Koester, D.; Farihi, J.
The existence of water in extrasolar planetary systems is of great interest because it constrains the potential for habitable planets and life. We have identified a circumstellar disk that resulted from the destruction of a water-rich and rocky extrasolar minor planet. The parent body formed and evolved around a star somewhat more massive than the…
ALMA observations of feeding and feedback in nearby Seyfert galaxies: an AGN-driven outflow in NGC 1433
Tacconi, L. J.; Krips, M.; Schinnerer, E. +9 more
We report ALMA observations of CO(3-2) emission in the Seyfert 2 galaxy NGC 1433 at the unprecedented spatial resolution of 0.''5 = 24 pc. Our aim is to probe active galactic nucleus (AGN) feeding and feedback phenomena through the morphology and dynamics of the gas inside the central kpc. The galaxy NGC 1433 is a strongly barred spiral with three…
CLASH: The Enhanced Lensing Efficiency of the Highly Elongated Merging Cluster MACS J0416.1-2403
Shu, X.; Zheng, W.; Moustakas, J. +21 more
We perform a strong lensing analysis of the merging galaxy cluster MACS J0416.1-2403 (M0416; z = 0.42) in recent CLASH/HST observations. We identify 70 new multiple images and candidates of 23 background sources in the range 0.7 <~ z phot <~ 6.14 including two probable high-redshift dropouts, revealing a highly elongated lens with…
Origins of weak lensing systematics, and requirements on future instrumentation (or knowledge of instrumentation)
Cropper, Mark; Schrabback, Tim; Hoekstra, Henk +11 more
The first half of this paper explores the origin of systematic biases in the measurement of weak gravitational lensing. Compared to previous work, we expand the investigation of point spread function instability and fold in for the first time the effects of non-idealities in electronic imaging detectors and imperfect galaxy shape measurement algor…
The 2012 Hubble Ultra Deep Field (UDF12): Observational Overview
Ono, Yoshiaki; Ouchi, Masami; Koekemoer, Anton M. +15 more
We present the 2012 Hubble Ultra Deep Field campaign (UDF12), a large 128 orbit Cycle 19 Hubble Space Telescope program aimed at extending previous Wide Field Camera 3 (WFC3)/IR observations of the UDF by quadrupling the exposure time in the F105W filter, imaging in an additional F140W filter, and extending the F160W exposure time by 50%, as well …
A Tight Connection between Gamma-Ray Outbursts and Parsec-scale Jet Activity in the Quasar 3C 454.3
Strelnitski, Vladimir; Walker, Gary; McHardy, Ian M. +42 more
We analyze the multi-frequency behavior of the quasar 3C 454.3 during three prominent γ-ray outbursts: 2009 Autumn, 2010 Spring, and 2010 Autumn. The data reveal a repeating pattern, including a triple flare structure, in the properties of each γ-ray outburst, which implies similar mechanism(s) and location for all three events. The multi-frequenc…
The SLUGGS Survey: kinematics for over 2500 globular clusters in 12 early-type galaxies
Spitler, Lee R.; Forbes, Duncan A.; Romanowsky, Aaron J. +10 more
We present a spectrophotometric survey of 2522 extragalactic globular clusters (GCs) around 12 early-type galaxies, nine of which have not been published previously. Combining space-based and multicolour wide-field ground-based imaging, with spectra from the Keck/DEep Imaging Multi-Object Spectrograph (DEIMOS) instrument, we obtain an average of 1…
Escape of Lyman continuum radiation from local galaxies. Detection of leakage from the young starburst Tol 1247-232
Hayes, M.; Zackrisson, E.; Leitet, E. +2 more
Context. It has been suggested that the escape fraction of hydrogen ionizing photons (fesc) from galaxies is evolving with time, but the picture is far from clear. While evidence for significant escape fractions has been found at high redshifts in several studies, the picture looks different in the closer universe. The lack of local det…
Confirmation of Faint Dwarf Galaxies in the M81 Group
Chiboucas, Kristin; Tully, R. Brent; Karachentsev, Igor D. +1 more
We have followed up on the results of a 65 deg2 CFHT/MegaCam imaging survey of the nearby M81 Group searching for faint and ultra-faint dwarf galaxies. The original survey turned up 22 faint candidate dwarf members. Based on two-color HST ACS/WFC and WFPC2 photometry, we now confirm 14 of these as dwarf galaxy members of the group. Dist…
The Ultraluminous X-Ray Sources NGC 1313 X-1 and X-2: A Broadband Study with NuSTAR and XMM-Newton
Hailey, Charles J.; Fabian, Andrew C.; Fürst, Felix +16 more
We present the results of NuSTAR and XMM-Newton observations of the two ultraluminous X-ray sources: NGC 1313 X-1 and X-2. The combined spectral bandpass of the two satellites enables us to produce the first spectrum of X-1 between 0.3 and 30 keV, while X-2 is not significantly detected by NuSTAR above 10 keV. The NuSTAR data demonstrate that X-1 …