Search Publications
The Burst Cluster: Dark Matter in a Cluster Merger Associated with the Short Gamma-Ray Burst, GRB 050509B
Dahle, H.; Kouveliotou, C.; Wijers, R. A. M. J. +11 more
We have identified a merging galaxy cluster with evidence of two distinct subclusters. The X-ray and optical data suggest that the subclusters are presently moving away from each other after closest approach. This cluster merger was discovered from observations of the first well-localized short-duration gamma-ray burst (GRB), GRB 050509B. The Swif…
A Search for Magnesium in Europa's Atmosphere
Brown, M. E.; Hörst, S. M.
Europa's tenuous atmosphere results from sputtering of the surface. The trace element composition of its atmosphere is therefore related to the composition of Europa's surface. Magnesium salts are often invoked to explain Galileo Near Infrared Mapping Spectrometer spectra of Europa's surface, thus magnesium may be present in Europa's atmosphere. W…
Nonlocal electron heating at the Earth's bow shock and the role of the magnetically tangent point
Schwartz, S. J.; Mitchell, J. J.
The solar wind interaction with the terrestrial magnetosphere results in a standing bow shock. Due to the shock's collisionless nature, the plasma in the magnetosheath is far from equilibrium. The highly mobile magnetosheath electrons move quickly between different points on the shock surface. Consequently, portions of phase space are populated wi…
Properties of sunspot penumbral grains observed with Hinode
Ichimoto, K.; Zhang, Y.
Context. Penumbral grains (PGs) are small-scale (subarcsec) bright features found in the bright penumbral filament in the outer parts of sunspots.
Aims: We aim to study properties of PGs at the blue continuum (4504 Å) and the G-band (4305 Å) by using simultaneous seeing free data obtained by Broadband Filter Imager (BFI) on board Hinode.
…
On Detecting Transient Phenomena
Bélanger, G.
Transient phenomena are interesting and potentially highly revealing of details about the processes under observation and study that could otherwise go unnoticed. It is therefore important to maximize the sensitivity of the method used to identify such events. In this article, we present a general procedure based on the use of the likelihood funct…
Atmospheric Imaging Assembly Response Functions: Solving the Fe VIII Problems with Hinode EIS Bright Point Data
Schmelz, J. T.; Jenkins, B. S.; Kimble, J. A.
The Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory is a state-of-the-art imager with the potential to perform an unprecedented time-dependent multi-thermal analysis at every pixel on scales that are short compared to the radiative and conductive cooling times. Recent results, however, have identified missing spectral lin…
Evidence for Amazonian mid-latitude glaciation on Mars from impact crater asymmetry
Mangold, Nicolas; Conway, Susan J.
We find that crater slopes in the mid-latitudes of Mars have a marked north-south asymmetry, with the pole-facing slopes being shallower. We mapped impact craters in two southern hemisphere sites (Terra Cimmeria and Noachis Terra) and one northern hemisphere site (Acidalia Planitia) and used elevation data from the High Resolution Stereo Camera (H…
Eclipses Observed by Large Yield RAdiometer (LYRA) - A Sensitive Tool to Test Models for the Solar Irradiance
Schmutz, W.; Shapiro, A. I.; Shapiro, A. V. +1 more
We analyze the light curves of the recent solar eclipses measured by the Herzberg channel (200 - 220 nm) of the Large Yield RAdiometer (LYRA) onboard Project for OnBoard Autonomy (PROBA2). The measurements allow us to accurately retrieve the center-to-limb variations (CLV) of the solar brightness. The formation height of the radiation depends on t…
Microphysics in Astrophysical Plasmas
Schwartz, Steven J.; Zweibel, Ellen G.; Goldman, Martin
Although macroscale features dominate astrophysical images and energetics, the physics is controlled through microscale transport processes (conduction, diffusion) that mediate the flow of mass, momentum, energy, and charge. These microphysical processes manifest themselves in key (all) boundary layers and also operate within the body of the plasm…
The XMM-Newton Spectrum of a Candidate Recoiling Supermassive Black Hole: An Elusive Inverted P-Cygni Profile
Jahnke, K.; Costantini, E.; Vignali, C. +12 more
We present a detailed spectral analysis of new XMM-Newton data of the source CXOC J100043.1+020637, also known as CID-42, detected in the COSMOS survey at z = 0.359. Previous works suggested that CID-42 is a candidate recoiling supermassive black hole (SMBH) showing also an inverted P-Cygni profile in the X-ray spectra at ~6 keV (rest) with an iro…