ULTRAVIOLET SPECTROSCOPY OF NARROW CORONAL MASS EJECTIONS
We present Ultraviolet Coronagraph Spectrometer (UVCS) observations of five narrow coronal mass ejections (CMEs) that were among 15 narrow CMEs originally selected by Gilbert and coworkers. Two events (1999 March 27, April 15) were "structured," i.e., in white-light data they exhibited well-defined interior features, and three (1999 May 9, May 21, June 3) were "unstructured," i.e., appeared featureless. In UVCS data the events were seen as 4°-13° wide enhancements of the strongest coronal lines H I Lyα and O VI λλ1032, 1037. We derived electron densities for several of the events from the Large Angle and Spectrometric Coronagraph Experiment (LASCO) C2 white-light observations. They are comparable to or smaller than densities inferred for other CMEs. We modeled the observable properties of examples of the structured (1999 April 15) and unstructured (1999 May 9) narrow CMEs at different heights in the corona between 1.5 and 2 R☉. The derived electron temperatures, densities, and outflow speeds are similar for those two types of ejections. They were compared with properties of polar coronal jets and other CMEs. We discuss different scenarios of narrow CME formation as either a jet formed by reconnection onto open field lines or a CME ejected by expansion of closed field structures. Overall, we conclude that the existing observations do not definitively place the narrow CMEs into the jet or the CME picture, but the acceleration of the 1999 April 15 event resembles acceleration seen in many CMEs, rather than constant speeds or deceleration observed in jets.

title: SIMULTANEOUS CHANDRA AND RXTE SPECTROSCOPY OF THE MICROQUASAR H 1743 − 22 : CLUES TO DISK WIND AND JET FORMATION FROM A VARIABLE IONIZED OUTFLOW
abstract: We observed the bright phase of the 2003 outburst of the Galac tic black hole candidate H 1743 − 22 in Xrays simultaneously withChandra andRXTE on four occasions. The Chandra/HETGS spectra reveal narrow, variable (He-like) Fe XXV and (H-like) Fe XXVI resonance abs orption lines. In the first observation, the Fe XXVI line has a FWHM of 1800± 400 km/s and a blue-shift of 700 ± 200 km/s, suggesting that the highly ionized medium is an outflow. Moreover, the Fe XXV line is obse rved to vary significantly on a timescale of a few hundred seconds in the first observation, which correspo nds to the Keplerian orbital period at approximately 104 rg (whererg = GM/c2). Our models for the absorption geometry suggest that a comb ination of geometric effects and changing ionizing flux are required to account fo r he large changes in line flux observed between observations, and that the absorption likely occurs at a rad ius less than 10 4 rg for a 10M⊙ black hole. Viable models for the absorption geometry include cyclic absorpti n due to an accretion disk structure, absorption in a clumpy outflowing disk wind, or possibly a combination of the se two. If the wind in H 1743 −322 has unity filling factor, the highest implied mass outflow rate is 20% of the Edd ington mass accretion rate. This wind may be a hot precursor to the Seyfert-like, outflowing “warm absorber” g eometries recently found in the Galactic black holes GX 339-4 and XTE J1650 −500. We discuss these findings in the context of ionized Fe abs orption lines found in the spectra of other Galactic sources, and connections to warm absorbers, winds, and jets in other accreting systems.

title: OBSERVATIONS AND INTERPRETATION OF A LOW CORONAL SHOCK WAVE OBSERVED IN THE EUV BY THE SDO/AIA
abstract: Taking advantage of both the high temporal and spatial resolutions of the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory, we studied a limb coronal shock wave and its associated extreme ultraviolet (EUV) wave that occurred on 2010 June 13. Our main findings are: (1) the shock wave appeared clearly only in the channels centered at 193 angstrom and 211 angstrom as a dome-like enhancement propagating ahead of its associated semi-spherical coronal mass ejection (CME) bubble; (2) the density compression of the shock is 1.56 according to radio data and the temperature of the shock is around 2.8 MK; (3) the shock wave first appeared at 05: 38 UT, 2 minutes after the associated flare has started and 1 minute after its associated CME bubble appeared; (4) the top of the dome-like shock wave set out from about 1.23 R-circle dot and the thickness of the shocked layer is similar to 2 x 10(4) km; (5) the speed of the shock wave is consistent with a slight decrease from about 600 km s(-1) to 550 km s(-1); and (6) the lateral expansion of the shock wave suggests a constant speed around 400 km s(-1), which varies at different heights and directions. Our findings support the view that the coronal shock wave is driven by the CME bubble, and the on-limb EUV wave is consistent with a fast wave or at least includes the fast wave component.

title: Deep Chandra Observations of the Crab-like Pulsar Wind Nebula G54.1+0.3 and Spitzer Spectroscopy of the Associated Infrared Shell
abstract: G54.1+0.3 is a young pulsar wind nebula (PWN), closely resembling the Crab, for which no thermal shell emission has been detected in X-rays. Recent Spitzer observations revealed an infrared (IR) shell containing a dozen point sources arranged in a ring-like structure, previously proposed to be young stellar objects. An extended knot of emission located in the NW part of the shell appears to be aligned with the pulsar's X-ray jet, suggesting a possible interaction with the shell material. Surprisingly, the IR spectrum of the knot resembles the spectrum of freshly formed dust in Cas A, and is dominated by an unidentified dust emission feature at 21 μm. The spectra of the shell also contain various emission lines and show that some are significantly broadened, suggesting that they originate in rapidly expanding supernova (SN) ejecta. We present the first evidence that the PWN is driving shocks into expanding SN ejecta and we propose an alternative explanation for the origin of the IR emission in which the shell is composed entirely of SN ejecta. In this scenario, the freshly formed SN dust is being heated by early-type stars belonging to a cluster in which the SN exploded. Simple dust models show that this interpretation can give rise to the observed shell emission and the IR point sources.

title: A DETAILED ANALYSIS OF A CYGNUS LOOP SHOCK-CLOUD INTERACTION
abstract: The XA region of the Cygnus Loop is a complex zone of radiative and nonradiatve shocks interacting with interstellar clouds. We combine five far ultraviolet spectral observations from the Hopkins Ultraviolet Telescope (HUT), a grid of 24 IUE spectra, and a high-resolution long-slit Hα spectrum to study the spatial emission line variations across the region. These spectral data are placed in context using ground-based optical emission-line images of the region and a far-UV image obtained by the Ultraviolet Imaging Telescope (UIT). The presence of high-ionization species (O VI, N V, and C IV) indicates a shock velocity near 170 km s-1 while other diagnostics indicate vsh ≈ 140 km s-1. It is likely that a large range of shock velocities may exist at a spatial scale smaller than we are able to resolve. By comparing C IV λ1550, C III λ977, and C III] λ1909, we explore resonance scattering across the region. We find that a significant column depth is present at all positions, including those not near bright optical or UV filaments. Analysis of the O VI doublet ratio suggests an average optical depth of about unity in that ion, while flux measurements of [Si VIII] λ1443 suggest a hot component in the region at just below 106 K. Given the brightness of the O VI emission and the age of the interaction, we rule out the mixing-layer interpretation of the UV emission. Furthermore, we formulate a picture of the XA region as that of an encounter of the blast wave with a finger of dense gas protruding inward from the pre-supernova cavity.

title: Observational Signatures of Particle Acceleration in Supernova Remnants
abstract: We evaluate the current status of supernova remnants as the sources of Galactic cosmic rays. We summarize observations of supernova remnants, covering the whole electromagnetic spectrum and describe what these observations tell us about the acceleration processes by high Mach number shock fronts. We discuss the shock modification by cosmic rays, the shape and maximum energy of the cosmic-ray spectrum and the total energy budget of cosmic rays in and surrounding supernova remnants. Additionally, we discuss problems with supernova remnants as main sources of Galactic cosmic rays, as well as alternative sources.

title: Radiation effects in detector electronics
abstract: Radiation effects produced in electronics for detectors operated at intense high-energy particle accelerators are reviewed. Both displacement damage in semiconductor material and long-lived ionization effects produced by charge trapping in dielectrics near interfaces are potentially serious. Hardening and test methods must recognize the particular circuit's functional requirements. The dominant defects and appropriate hardening method depend on the important parameter (e.g., offset, leakage, noise) as well as the operating frequency.