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Globular cluster system erosion and nucleus formation in elliptical galaxies
Capuzzo-Dolcetta, R.; Tesseri, A.
The radial distribution of globular clusters in galaxies is always less peaked to the centre than that of the halo stars. Extending previous work to a sample of Hubble Space Telescope globular cluster systems in ellipticals, we evaluate the number of clusters potentially lost to the galactic centre as the integrals of the difference between the ob…
Direct Measurement of the Jet Geometry in Seyfert Galaxies
Clarke, C. J.; Pringle, J. E.; Schmitt, H. R. +3 more
We demonstrate that by combining optical, radio, and X-ray observations of a Seyfert galaxy, it is possible to provide a direct measurement of the angle β between the direction of the radio jet and the normal to the plane of the spiral host galaxy. To do so, we make the assumptions that the inner radio jet is perpendicular to the X-ray observed in…
Hubble Space Telescope and VLA Observations of Two Optical Continuum Knots in the Jet of 3C 380
Baum, Stefi A.; O'Dea, Christopher P.; Biretta, John A. +1 more
We present Hubble Space Telescope Wide Field Planetary Camera 2 broadband red and linear ramp filter (isolating redshifted [O II] lambda3727) observations and subarcsecond-resolution 15, 22, and 43 GHz VLA observations of the radio-loud quasar 3C 380. We confirm the report of de Vries et al. that there is good correspondence between the locations …
Lifetime Measurements for Ground Term Transitions in TA II, W II, and RE II
Wahlgren, G. M.; Henderson, M.; Brage, T. +4 more
Lifetime measurements have been made for the radiation emitted in the ground term transitions of the nominal form 5s25p65dx6s-5s25p65dx6p in Ta II (x=3), W II (x=4), and Re II (x=5). Supporting theoretical calculations have also been performed to characterize configuration interacti…
Radius and distance estimates of the isolated neutron stars Geminga and PSR B0656+14 using optical photometry
Golden, A.; Shearer, A.
Integrated ground-based and HST optical studies of isolated neutron stars have provided important independent datasets in the determination of emission activity, particularly in the fitting of anticipated Rayleigh-Jeans extrapolations from EUV/soft X-ray datasets, despite their intrinsic faintness. Differentiation of the pulsed and unpulsed fluxes…
Mid-Infrared Emission from E+A Galaxies in the Coma Cluster
Rieke, G. H.; Quillen, A. C.; Rieke, M. J. +2 more
We have used ISO to observe at 12 µm seven E+A galaxies plus an additional emission-line galaxy, all in the Coma Cluster. E+A galaxies lacking narrow emission lines have 2.2-12 µm flux density ratios or limits similar to old stellar populations (typical of early-type galaxies). Only galaxies with emission lines have enhanced 12 µ…
Constraints on the Tropospheric Cloud Structure of Jupiter from Spectroscopy in the 5-µm Region: A Comparison between Voyager/IRIS, Galileo-NIMS, and ISO-SWS Spectra
Carlson, R. W.; Drossart, P.; Encrenaz, Th. +2 more
The 5-µm window in the spectrum of Jupiter is one of the few regions that gives access to the vertical structure of the troposphere between pressure levels of approximately 4 and 8 bar. Voyager/IRIS spectra obtained in 1979 during the Voyager flybys have been analyzed intensively over the past two decades. Most of these analyses concluded on…
Acceleration Profile of the Slow Solar Wind as Inferred from Gradual Mass Ejections Observed by LASCO
Stenborg, Guillermo; Srivastava, Nandita; Inhester, Bernd +2 more
The slow solar wind (< 400 km s-1) appears to initiate from the regions in the corona where magnetic fields are closed, or from the interface between streamers and other coronal regions. The nature of the acceleration of slow solar wind is not yet well known. LASCO observations of gradually evolving mass ejections offer us a good opp…
The Struve-Sahade Effect: A Tale of Three Stars
Gies, Douglas R.; Riddle, Reed; Penny, Laura R. +1 more
The ``Struve-Sahade effect'' (S-S effect) is the apparent weakness of lines of the secondary in massive binaries when the secondary is receding. This effect poses problems for the accurate reconstruction of the separated primary and secondary spectra. We have reexamined IUE spectra of three classical, hot binaries studied by D. Stickland in 1997. …
Multiple-Thread Model of a Prominence Observed by SUMER and EIT on SOHO
Wilhelm, K.; Schmieder, B.; Dammasch, I. E. +1 more
A quiescent polar crown prominence was observed at Meudon in Hα and Ca ii lines, and by EIT and SUMER on board SOHO in UV lines from 9 to 10 March 1996. SUMER observed the prominence continuously in a scanning mode between 21:40 UT on 9 March, and 18:13 UT on 10 March, in the nitrogen line N v (λ1238) with a 1 arc sec2 resolution. Altog…