Search Publications
The Reverse Shock of SNR 1987A at 18 Years after Outburst
Smith, Nathan; Zhekov, Svetozar A.; Heng, Kevin +3 more
We use low-dispersion spectra obtained at the Magellan Observatory to study the broad Hα emission from the reverse shock of the infant supernova remnant SNR 1987A. These spectra demonstrate that the spatiokinematic structure of the reverse shock can be distinguished from that of the circumstellar ring and hot spots, even at ground-based spatial re…
Multialtitude Observations of a Coronal Jet during the Third Whole Sun Month Campaign
Mason, H. E.; Thompson, B. J.; Raymond, J. C. +11 more
On 1999 August 26, a coronal jet occurred at the northwest limb near a sigmoid active region (AR 8668) that was the target for a joint observation plan (SOHO joint observing program 106) during the third Whole Sun Month Campaign. This jet was observed by several instruments at the limb (SOHO/CDS, SOHO/EIT, TRACE, and Mauna Loa Solar Observatory CH…
Correlation Heights of the Sources of Solar Ultraviolet Emission Lines in a Quiet-Sun Region
Wilhelm, Klaus; Marsch, Eckart; Wang, Jing-Xiu +4 more
The radiance and Doppler-velocity maps of the emission lines of Si II, C IV, and Ne VIII obtained in a quiet region of the Sun by SUMER (Solar Ultraviolet Measurements of Emitted Radiation) are correlated with the vertical component, Bz, of the magnetic field vector as extrapolated, by means of a force-free field model, from the photosp…
Faint Fuzzies and the Formation of Lenticular Galaxies
Brodie, Jean; Burkert, Andreas; Larsen, Soeren
We investigate the dynamical state of a new class of extended star clusters known as ``faint fuzzies,'' which were discovered in two nearby S0 galaxies, NGC 1023 and NGC 3384. It is shown that the faint fuzzies of NGC 1023 lie in a fast-rotating ringlike structure within the galactic disk with mean radius of 5 kpc, rotational velocity of 200 km s<…
Integral Field Spectroscopy of the Central Regions of 3C 120: Evidence of a Past Merging Event
Christensen, L.; García-Lorenzo, B.; Mediavilla, E. +2 more
Optical integral field spectroscopy (IFS), combined with Hubble Space Telescope (HST) WFPC imaging, was used to characterize the central regions of the Seyfert 1 radio galaxy 3C 120. We carried out the analysis of the data, deriving intensity maps of different emission lines and the continua at different wavelengths from the observed spectra. Appl…
A Study of Flare-associated X-Ray Plasma Ejections. I. Association with Coronal Mass Ejections
Cho, K. -S.; Moon, Y. -J.; Park, Y. D. +2 more
We have made a comprehensive statistical study of the relationship between flare-associated X-ray plasma ejections and coronal mass ejections (CMEs). For this we considered all flare-mode data in Yohkoh SXT observations from 1999 April to 2001 March and then selected 279 limb flares seen at longitudes greater than 60°. For these events, we identif…
XMM-Newton Observations of Red AGNs
Wilkes, B. J.; Hines, D. C.; Smith, P. S. +5 more
XMM-Newton spectra of five red 2MASS active galactic nuclei (AGNs), selected from a sample observed by Chandra to be relatively X-ray bright and to cover a range of hardness ratios, confirm the presence of substantial absorbing material in three sources with optical classifications ranging from type 1 to type 2. A flat (hard) power-law continuum i…
Emission-Line Spectroscopy of Damped Lyα Systems: The Case of SBS 1543+593/HS 1543+5921
Turnshek, David A.; Hopkins, Andrew M.; Miller, Christopher J. +4 more
We report HST/STIS spectroscopy and Gemini/GMOS-N imaging of the Damped Lyα (DLA) system toward HS 1543+5921 caused by the host star-forming galaxy (SFG) SBS 1543+593. The Gemini image shows new morphological details of this well-resolved DLA galaxy. In combination with previous optical spectra, the new UV spectra enable us to compare, for the fir…
16 µm Imaging around the Hubble Deep Field-North with the Spitzer IRS
Chary, R.; Armus, L.; Charmandaris, V. +3 more
We present a pilot study of 16 µm imaging within the GOODS northern field. Observations were obtained using the ``peak-up'' imaging capability of the Spitzer IRS. We survey 35 arcmin2 to an average 3 σ depth of 0.075 mJy and detect 149 sources. The survey partially overlaps the area imaged at 15 µm by the ISO, and we demonst…
Recovering Solar Toroidal Field Dynamics from Sunspot Location Patterns
Norton, Aimee A.; Gilman, Peter A.
We analyze both Kitt Peak magnetogram data and MDI continuum intensity sunspot data to search for the following solar toroidal band properties: width in latitude and the existence of a tipping instability (longitudinal m=1 mode) for any time during the solar cycle. In order to determine the extent to which we can recover the toroidal field dynamic…