Search Publications
The Rotation of the Deep Solar Layers
Henney, C. J.; García, R. A.; Corbard, T. +3 more
From the analysis of low-order GOLF+MDI sectoral modes (l<=3, 6<=n<=15, |m|=l) and LOWL data (l>3), we derive the radial rotation profile by assuming no latitudinal dependence in the solar core. These low-order acoustic modes contain the most statistically significant information about the rotation of the deepest solar layers and shoul…
The Assembly of Massive Galaxies from Near-Infrared Observations of the Hubble Deep Field-South
Fontana, A.; Vanzella, E.; Cristiani, S. +7 more
We use a deep KAB<=25 galaxy sample in the Hubble Deep Field-South to trace the evolution of the cosmological stellar mass density from z~=0.5 to z~=3. We find clear evidence for a decrease of the average stellar mass density at high redshift, 2<=z<=3.5, that is 15+25-5% of the local value, 2 times higher …
Parent Stars of Extrasolar Planets. VII. New Abundance Analyses of 30 Systems
Suntzeff, Nicholas B.; Gonzalez, Guillermo; Laws, Chris +4 more
The results of new spectroscopic analyses of 30 stars with giant planet and/or brown dwarf companions are presented. Values for Teff and [Fe/H] are used in conjunction with Hipparcos data and Padua isochrones to derive masses, ages, and theoretical surface gravities. These new data are combined with spectroscopic and photometric metalli…
A deep survey of heavy element lines in planetary nebulae - I. Observations and forbidden-line densities, temperatures and abundances
Tsamis, Y. G.; Barlow, M. J.; Liu, X. -W. +2 more
We present deep optical spectrophotometry of 12 Galactic planetary nebulae (PNe) and three Magellanic Cloud PNe. Nine of the Galactic PNe were observed by scanning the slit of the spectrograph across the nebula, yielding relative line intensities for the entire nebula that are suitable for comparison with integrated nebular fluxes measured in othe…
Hubble Space Telescope Images of Submillimeter Sources: Large Irregular Galaxies at High Redshift
Chapman, S. C.; Conselice, C.; Yan, H. +2 more
We present new Hubble Space Telescope Space Telescope Imaging Spectrograph (STIS) high-resolution optical imaging of a sample of 13 submillimeter luminous galaxies for which the optical emission has been pinpointed either through radio 1.4 GHz or millimeter interferometry. We find a predominance of irregular and complex morphologies in the sample,…
A Search for CMEs Associated with Big Flares
Andrews, M. D.
The relationship between flares and coronal mass ejections (CMEs) remains a topic of active research. This paper considers a complete set of 311 M- and X-class GOES soft X-ray flares observed during the years 1996-1999. The durations of these flares have been determined as part of this study. Possible CME candidates for the 229 flares with good LA…
A New Method for Estimating Widths, Velocities, and Source Location of Halo Coronal Mass Ejections
Gopalswamy, N.; Yashiro, S.; Michałek, G.
It is well known that coronagraphic observations of halo coronal mass ejections (CMEs) are subject to projection effects. Viewing in the plane of the sky does not allow us to determine the crucial parameters that define the geoeffectiveness of CMEs, such as the space speed, width, or source location. Assuming that halo CMEs have constant velocitie…
Kinematics of 10 Early-Type Galaxies from Hubble Space Telescope and Ground-based Spectroscopy
Filippenko, Alexei V.; Ho, Luis C.; Gebhardt, Karl +11 more
We present stellar kinematics for a sample of 10 early-type galaxies observed using the Space Telescope Imaging Spectrograph (STIS) aboard the Hubble Space Telescope and the Modular Spectrograph on the MDM Observatory 2.4 m telescope. These observations are a part of an ongoing program to understand the coevolution of supermassive black holes and …
Infrared stellar populations in the central parts of the Milky Way galaxy
Blommaert, J. A. D. L.; Glass, I. S.; Omont, A. +7 more
Near- and mid-IR survey data from DENIS and ISOGAL are used to investigate the structure and formation history of the inner 10° (1.4 kpc) of the Milky Way galaxy. Synthetic bolometric corrections and extinction coefficients in the near- and mid-infrared (mid-IR) are derived for stars of different spectral types, to allow the transformation of theo…
SUMER spectral observations of post-flare supra-arcade inflows
Innes, D. E.; McKenzie, D. E.; Wang, Tongjiang
On 21 April 2002 a large eruptive flare on the west limb of the Sun developed a bright, very dynamic, post-flare arcade. In TRACE 195 Å images, a series of dark, sunward moving flows were seen against the bright extreme ultraviolet (EUV) arcade. SUMER obtained a series of spectra of the dark EUV flows in the lines C ii, Fe xii, and Fe xxi at a fix…