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The Abundances of Polyacetylenes Toward CRL618
Cernicharo, J.; Fonfría, J. P.; Richter, M. J. +1 more
We present a mid-infrared high spectral resolution spectrum of CRL618 in the frequency ranges 778-784 and 1227-1249 cm-1 (8.01-8.15 and 12.75-12.85 µm) taken with the Texas Echelon-cross-Echelle Spectrograph (TEXES) and the Infrared Telescope Facility (IRTF). We have identified more than 170 rovibrational lines arising from C…
Observational Evidence of Changing Photospheric Vector Magnetic Fields Associated with Solar Flares
Zhang, H. Q.; Su, J. T.; Guo, J. +6 more
Recent observations have provided evidence that the solar photospheric magnetic fields could have rapid and permanent changes in both longitudinal and transverse components associated with major flares. As a result, the Lorentz force (LF) acting on the solar photosphere and solar interior could be perturbed, and the change of LF is always nearly i…
The Last Eight-billion Years of Intergalactic Si IV Evolution
Prochaska, J. Xavier; Chen, Hsiao-Wen; Thom, Christopher +1 more
We identified 24 Si IV absorption systems with z <~ 1 from a blind survey of 49 low-redshift quasars with archival Hubble Space Telescope ultraviolet spectra. We relied solely on the characteristic wavelength separation of the doublet to automatically detect candidates. After visual inspection, we defined a sample of 20 definite (group G = 1) a…
An XMM-Newton Study of the Bright, Nearby Supernova Remnant G296.1-0.5
Gaensler, B. M.; Hughes, J. P.; Castro, D. +2 more
We present a detailed study of the supernova remnant (SNR) G296.1-0.5, performed using observations with the European Photon Imaging Camera (EPIC) and Reflection Grating Spectrometer instruments of the XMM-Newton satellite. G296.1-0.5 is a bright remnant that displays an incomplete multiple-shell morphology in both its radio and X-ray images. We u…
The Displaced Dusty Interstellar Medium of NGC 3077: Tidal Stripping in the M 81 Triplet
Helou, G.; Roussel, H.; Murphy, E. J. +32 more
We present the detection of extended (~30 kpc2) dust emission in the tidal H I arm near NGC 3077 (member of the M 81 triplet) using SPIRE on board Herschel. Dust emission in the tidal arm is typically detected where the H I column densities are >1021 cm-2. The SPIRE band ratios show that the dust in the tidal ar…
Sirius B Imaged in the Mid-infrared: No Evidence for a Remnant Planetary System
Close, Laird M.; Skemer, Andrew J.
Evidence is building that remnants of solar systems might orbit a large percentage of white dwarfs, as the polluted atmospheres of DAZ and DBZ white dwarfs indicate the very recent accretion of metal-rich material. Some of these polluted white dwarfs are found to have large mid-infrared excesses from close-in debris disks that are thought to be re…
Three-dimensional Structure of Microwave Sources from Solar Rotation Stereoscopy Versus Magnetic Extrapolations
Jing, Ju; Wang, Haimin; Fleishman, Gregory D. +5 more
We use rotation stereoscopy to estimate the height of a steady-state solar feature relative to the photosphere, based on its apparent motion in the image plane recorded over several days of observation. The stereoscopy algorithm is adapted to work with either one- or two-dimensional data (i.e., from images or from observations that record the proj…
Comparison of Seismic Signatures of Flares Obtained by SOHO/Michelson Doppler Imager and GONG Instruments
Zharkova, V. V.; Matthews, S. A.; Zharkov, S.
The first observations of seismic responses to solar flares were carried out using time-distance (TD) and holography techniques applied to SOHO/Michelson Doppler Imager (MDI) Dopplergrams obtained from space and unaffected by terrestrial atmospheric disturbances. However, the ground-based network GONG is potentially a very valuable source of sunqu…
A High-metallicity, High-velocity Cloud Along the Mrk 421 Sight Line: A Tracer of Complex M?
Shull, J. Michael; Danforth, Charles W.; Yao, Yangsen
We present a new measurement, 0.85-3.5 Z sun, of the metallicity of high-velocity cloud (HVC) Complex M by analyzing ultraviolet spectroscopic observations of the blazar Mrk 421 taken with the Cosmic Origins Spectrograph on the Hubble Space Telescope and the Far-Ultraviolet Spectroscopic Explorer. Although an HVC at V LSR = -…
Intracluster Medium of the Merging Cluster A3395
Singh, K. P.; Saikia, D. J.; Hunstead, R. W. +1 more
We present a detailed imaging and spectral analysis of the merging environment of the bimodal cluster A3395 using X-ray and radio observations. X-ray images of the cluster show five main constituents of diffuse emission: A3395 NE, A3395 SW, A3395 NW, A3395 W, and a filament connecting NE to W. X-ray surface brightness profiles of the cluster did n…