Search Publications
EUV Wave Reflection from a Coronal Hole
Temmer, M.; Howard, R. A.; Gopalswamy, N. +7 more
We report on the detection of EUV wave reflection from a coronal hole, as observed by the Solar Terrestrial Relations Observatory mission. The EUV wave was associated with a coronal mass ejection (CME) erupting near the disk center. It was possible to measure the kinematics of the reflected waves for the first time. The reflected waves were genera…
Early assembly of the most massive galaxies
Hilton, Matt; Stott, John P.; West, Michael J. +15 more
The current consensus is that galaxies begin as small density fluctuations in the early Universe and grow by in situ star formation and hierarchical merging. Stars begin to form relatively quickly in sub-galactic-sized building blocks called haloes which are subsequently assembled into galaxies. However, exactly when this assembly takes place is a…
HiZELS: a high-redshift survey of Hα emitters - II. The nature of star-forming galaxies at z = 0.84
Ivison, R. J.; Smail, Ian; Cirasuolo, M. +7 more
New results from a large survey of Hα emission-line galaxies at z = 0.84 using the Wide Field Camera on the United Kingdom Infrared Telescope and a custom narrow-band filter in the J band are presented as part of the High-z Emission Line Survey (HiZELS). The deep narrow-band images reach an effective flux limit of FHα ~ 10-16…
Discovery of jarosite within the Mawrth Vallis region of Mars: Implications for the geologic history of the region
Glotch, Timothy D.; Farrand, William H.; Swayze, Gregg A. +2 more
Analysis of visible to near infrared reflectance data from the MRO CRISM hyperspectral imager has revealed the presence of an ovoid-shaped landform, approximately 3 by 5 km in size, within the layered terrains surrounding the Mawrth Vallis outflow channel. This feature has spectral absorption features consistent with the presence of the ferric sul…
Every BCG with a Strong Radio Agn has an X-Ray Cool Core: Is the Cool Core-Noncool Core Dichotomy Too Simple?
Sun, M.
The radio active galactic nucleus (AGN) feedback in X-ray cool cores has been proposed as a crucial ingredient in the evolution of baryonic structures. However, it has long been known that strong radio AGNs also exist in "noncool core" clusters, which brings up the question whether an X-ray cool core is always required for the radio feedback. In t…
The 2008 Luminous Optical Transient in the Nearby Galaxy NGC 300
Walter, Frederick M.; Bond, Howard E.; Humphreys, Roberta M. +4 more
A luminous optical transient (OT) that appeared in NGC 300 in early 2008 had a maximum brightness, MV sime -12 to -13, intermediate between classical novae and supernovae. We present ground-based photometric and spectroscopic monitoring and adaptive-optics imaging of the OT, as well as pre- and postoutburst space-based imaging with the …
Accretion disc variability in the hard state of black hole X-ray binaries
Wilkinson, Tony; Uttley, Philip
XMM-Newton X-ray spectra of the hard state black hole X-ray binaries (BHXRBs) SWIFTJ1753.5-0127 and GX339-4 show evidence for accretion disc blackbody emission, in addition to hard power laws. The soft and hard band power spectral densities (PSDs) of these sources demonstrate variability over a wide range of time-scales. However, on time-scales of…
Physical Conditions in the Interstellar Medium of Intensely Star-Forming Galaxies at Redshift~2
Bournaud, F.; Chemin, L.; Lehnert, M. D. +5 more
We analyze the physical conditions in the interstellar gas of 11 actively star-forming galaxies at z~2, based on integral-field spectroscopy from the ESO-VLT and Hubble Space Telescope/Near Infrared Camera and Multi-Object Spectrometer imaging. We concentrate on the high Hα surface brightnesses, large line widths, line ratios, and the clumpy natur…
Observations of Turbulence Generated by Magnetic Reconnection
Eastwood, J. P.; Bale, S. D.; Phan, T. D. +1 more
Spacecraft observations of turbulence within a magnetic reconnection (guide field ∼0) ion diffusion region are presented. In the inertial subrange, electric and magnetic fluctuations both followed a -5/3 power law; at higher frequencies, the spectral indices were -1 and -8/3, respectively. The dispersion relation was found to be consistent with fa…
An asymmetric distribution of lakes on Titan as a possible consequence of orbital forcing
Lorenz, R. D.; Lunine, J. I.; Hayes, A. G. +3 more
A set of lakes filled or partially filled with liquid hydrocarbon and empty lake basins have been discovered in the high latitudes of Saturn's moon Titan. These features were mapped by the radar instrument on the Cassini orbiter. Here we quantify the distribution of the lakes and basins, and show a pronounced hemispheric asymmetry in their occurre…