Search Publications
The Extraordinary Multi-tailed Main-belt Comet P/2013 P5
Mutchler, Max; Jewitt, David; Agarwal, Jessica +2 more
Hubble Space Telescope observations of main-belt comet P/2013 P5 reveal an extraordinary system of six dust tails that distinguish this object from any other. Observations two weeks apart show dramatic morphological change in the tails while providing no evidence for secular fading of the object as a whole. Each tail is associated with a unique ej…
The Firm Redshift Lower Limit of the Most Distant TeV-detected Blazar PKS 1424+240
Filippenko, A. V.; Furniss, A.; Williams, D. A. +7 more
We present the redshift lower limit of z >= 0.6035 for the very high energy (VHE; E >= 100 GeV) emitting blazar PKS 1424+240 (PG 1424+240). This limit is inferred from Lyβ and Lyγ absorption observed in the far-ultraviolet spectra from the Hubble Space Telescope/Cosmic Origins Spectrograph. No VHE-detected blazar has shown solid spectroscopi…
Thermodynamics of the Coma Cluster Outskirts
Simionescu, A.; Fabian, A. C.; Allen, S. W. +10 more
We present results from a large mosaic of Suzaku observations of the Coma Cluster, the nearest and X-ray brightest hot (~8 keV), dynamically active, non-cool core system, focusing on the thermodynamic properties of the intracluster medium on large scales. For azimuths not aligned with an infalling subcluster toward the southwest, our measured temp…
A Near-infrared Transmission Spectrum for the Warm Saturn HAT-P-12b
Deming, Drake; Knutson, Heather; Line, Michael R. +2 more
We present a Hubble Space Telescope Wide Field Camera-3 (WFC3) transmission spectrum for the transiting exoplanet HAT-P-12b. This warm (1000 K) sub-Saturn-mass planet has a smaller mass and a lower temperature than the hot Jupiters that have been studied so far. We find that the planet's measured transmission spectrum lacks the expected water abso…
The COS/UVES Absorption Survey of the Magellanic Stream. II. Evidence for a Complex Enrichment History of the Stream from the Fairall 9 Sightline
Richter, Philipp; Bland-Hawthorn, Joss; Fox, Andrew J. +5 more
We present a multi-wavelength study of the Magellanic Stream (MS), a massive gaseous structure in the Local Group that is believed to represent material stripped from the Magellanic Clouds. We use ultraviolet, optical and radio data obtained with HST/COS, VLT/UVES, FUSE, GASS, and ATCA to study metal abundances and physical conditions in the Strea…
QSO Absorption Systems Detected in Ne VIII: High-metallicity Clouds with a Large Effective Cross Section
Sembach, K. R.; Lehner, N.; Jenkins, E. B. +5 more
Using high-resolution, high signal-to-noise ultraviolet spectra of the z em = 0.9754 quasar PG1148+549 obtained with the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope, we study the physical conditions and abundances of Ne VIII+O VI absorption line systems at z abs = 0.68381, 0.70152, 0.72478. In addition to …
A Herschel Study of D/H in Water in the Jupiter-family Comet 45P/Honda-Mrkos-Pajdušáková and Prospects for D/H Measurements with CCAT
Küppers, M.; Hartogh, P.; Crovisier, J. +11 more
We present Herschel observations of water isotopologues in the atmosphere of the Jupiter-family comet 45P/Honda-Mrkos-Pajdušáková. No HDO emission is detected, with a 3σ upper limit of 2.0 × 10-4 for the D/H ratio. This value is consistent with the earlier Herschel measurement in the Jupiter-family comet 103P/Hartley 2. The canonical va…
CANDELS: The Correlation between Galaxy Morphology and Star Formation Activity at z ~ 2
Bell, Eric F.; Ferguson, Henry C.; Giavalisco, Mauro +13 more
We discuss the state of the assembly of the Hubble sequence in the mix of bright galaxies at redshift 1.4 < z <= 2.5 with a large sample of 1671 galaxies down to H AB ~ 26, selected from the HST/ACS and WFC3 images of the GOODS-South field obtained as part of the GOODS and CANDELS observations. We investigate the relationship betw…
Distribution of High-mass X-Ray Binaries in the Milky Way
Coleiro, Alexis; Chaty, Sylvain
Observations of the high-energy sky, particularly with the INTEGRAL satellite, have quadrupled the number of supergiant X-ray binaries observed in the Galaxy and revealed new populations of previously hidden high-mass X-ray binaries (HMXBs), raising new questions about their formation and evolution. The number of detected HMXBs of different types …
Collisionless Damping at Electron Scales in Solar Wind Turbulence
Howes, G. G.; TenBarge, J. M.; Dorland, W.
The dissipation of turbulence in the weakly collisional solar wind plasma is governed by unknown kinetic mechanisms. Two candidates have been suggested to play an important role in the dissipation, collisionless damping via wave-particle interactions and dissipation in small-scale current sheets. High resolution spacecraft measurements of the turb…