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Kinematics of coronal mass ejections between 2 and 30 solar radii. What can be learned about forces governing the eruption?
Vršnak, B.; Gopalswamy, N.; Sudar, D. +1 more
Kinematics of more than 5000 coronal mass ejections (CMEs) measured in the distance range 2-30 solar radii is investigated. A distinct anticorrelation between the acceleration, a, and the velocity, v, is found. In the linear form, it can be represented as a=-k1(v-v0), where v0=400 km s-1, i.e., most of C…
Hubble Space Telescope Imaging and Keck Spectroscopy of z ~ 6 i-Band Dropout Galaxies in the Advanced Camera for Surveys GOODS Fields
Treu, Tommaso; Bunker, Andrew J.; McMahon, Richard G. +3 more
We measure the surface density of i'-band dropout galaxies at z~6 through wide-field Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) imaging and ultradeep Keck DEIMOS spectroscopy. Using deep HST ACS SDSS i' (F775W) and SDSS z' (F850LP) imaging from the Great Observatories Origins Deep Survey-North (GOODS-N 200 arcmin2), …
New perspectives on Titan's upper atmosphere from a reanalysis of the Voyager 1 UVS solar occultations
Strobel, Darrell F.; Vervack, Ronald J.; Sandel, Bill R.
We have reanalyzed the Voyager 1 UVS solar occultations by Titan to expand upon previous analyses and to resolve inconsistencies that have been noted in the scientific literature. To do so, we have developed a detailed model of the UVS detector and improved both the data reduction methods and retrieval techniques. In comparison to the values previ…
The Relationship Between Black Hole Mass and Velocity Dispersion in Seyfert 1 Galaxies
Green, Richard F.; Gebhardt, Karl; Bower, Gary +2 more
Black hole masses in active galactic nuclei are difficult to measure using conventional dynamical methods but can be determined using the technique of reverberation mapping. However, it is important to verify that the results of these different methods are equivalent. This can be done indirectly, using scaling relations between the black hole and …
The European Large-Area ISO Survey (ELAIS): the final band-merged catalogue
Elbaz, D.; Genzel, R.; Pozzi, F. +76 more
We present the final band-merged European Large-Area ISO Survey (ELAIS) Catalogue at 6.7, 15, 90 and 175 µm, and the associated data at U, g', r', i', Z, J, H, K and 20 cm. The origin of the survey, infrared and radio observations, data-reduction and optical identifications are briefly reviewed, and a summary of the area covered and the comp…
Arp 299: A Second Merging System with Two Active Nuclei?
Maraschi, L.; Ballo, L.; Tavecchio, F. +3 more
Recent BeppoSAX observations of Arp 299, a powerful far-IR merging starburst system composed of IC 694 and NGC 3690, clearly unveiled for the first time in this system the presence of a strongly absorbed active galactic nucleus (AGN). However, the system was not spatially resolved by BeppoSAX. Here we present the analysis of archival Chandra and (…
Eruption of a Multiple-Turn Helical Magnetic Flux Tube in a Large Flare: Evidence for External and Internal Reconnection That Fits the Breakout Model of Solar Magnetic Eruptions
Moore, R. L.; Gary, G. Allen
We present observations and an interpretation of a unique multiple-turn spiral flux tube eruption from active region 10030 on 2002 July 15. The TRACE C IV observations clearly show a flux tube that is helical and erupting from within a sheared magnetic field. These observations are interpreted in the context of the breakout model for magnetic fiel…
Hubble Space Telescope STIS Ultraviolet Spectral Evidence of Outflow in Extreme Narrow-Line Seyfert 1 Galaxies. I. Data and Analysis
Leighly, Karen M.; Moore, John R.
We present Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph observations of two extreme narrow-line Seyfert 1 galaxies (NLS1's), IRAS 13224-3809 and 1H 0707-495. The spectra are characterized by very blue continua; broad, strongly blueshifted high-ionization lines (including C IV and N V); and narrow, symmetric intermediate- (incl…
The distance to the giant elliptical galaxy NGC 5128
Rejkuba, M.
The distance to NGC 5128, the central galaxy of the Centaurus group and the nearest giant elliptical to us, has been determined using two independent distance indicators: the Mira period-luminosity (PL) relation and the luminosity of the tip of the red giant branch (RGB). The data were taken at two different locations in the halo of NGC 5128 with …
Time-Distance Helioseismology: Noise Estimation
Birch, A. C.; Gizon, L.
As in global helioseismology, the dominant source of noise in time-distance helioseismology measurements is realization noise due to the stochastic nature of the excitation mechanism of solar oscillations. Characterizing noise is important for the interpretation and inversion of time-distance measurements. In this paper we introduce a robust defin…