Search Publications
Geomagnetic storms with H 400nT during 1979-99
Kumar, Santosh; Pratap Yadav, Mahendra
The effect of solar features on geospheric conditions leading to ninety nine geomagnetic storms (GMSs) with H400nT and Ap20 have been investigated using interplanetary magnetic field (IMF), solar wind plasma (SWP) and solar geophysical data (SGD) during the period 1979-99. H, X-ray solar o o flares occured within lower latitudinal zone i.e., 30 N-…
HST imaging of radio galaxies at /z=0.2: a comparison with quasar hosts and normal ellipticals
McLure, R. J.; Dunlop, J. S.; Hughes, D. H. +3 more
We summarise the results of our recently completed HST R-band study of low-redshift (0.1< z<0.25) FRII radio galaxies along with the host galaxies of quasars of similar redshifts. We find that, like radio galaxies, the hosts of radio-loud quasars and all but the least luminous radio-quiet quasars are massive elliptical galaxies with relative…
Multiple-loop structure of a solar flare from Microwave, EUV and X-ray Imaging Data
Kundu, M. R.; Garaimov, V. I.
We present the results of an analysis of a flare event of importance M2.8 that occurred at 00:56 UT 28 August 1999. The analysis is based upon observations made with the Nobeyama radioheliograph (NoRH) and polarimeters (NoRP), TRACE, SOHO/MDI, EIT, and Yohkoh/SXT. The images show a very complex flaring region. Pre-flare TRACE and EIT images at 00:…
Information from the Kinematics of F and G Stars in the Solar Neighborhood
Zhao, Gang; Shi, Jian-Rong; Chen, Yu-Qin
We have calculated the orbital parameters for 90 stars in Chen et al. and updated the kinematic data for stars in Edvardsson et al. by using the accurate Hipparcos parallaxes and proper motions, and recalculated the α-element abundances in Edvardsson et al. in a way consistent with Chen et al. The two sets of data are combined in a study of stella…
Two jets from the Orion nebula (M42) `proplyds': kinematics, morphologies and origins
Redman, M. P.; Meaburn, J.; Graham, M. F.
A spatially unresolved velocity feature, with an approaching radial velocity of ~100 km s-1 with respect to the systemic radial velocity, in a position-velocity array of [OIII] 5007-Å line profiles is identified as the kinematical counterpart of a jet from the proplyd LV 5 (158-323) in the core of the Orion nebula. The only candidate in…
Interplanetary lyman alpha observations of swan during the rising phase of the 23rd solar cycle
Schmidt, W.; Bertaux, J. -L.; Lallement, R. +5 more
In this work we show the development of the intensity pattern of the interplanetary Lyman α sky background radiation between 1996 and 1999 as measured by the SWAN instrument. The results show that the intensity pattern has changed considerably in three years. The pattern with two maxima in the northern and southern hemispheres observed in 1996 has…
The nuclear dust disks of five nearby 3CR elliptical galaxies
Sparks, W. B.; Baum, S. A.; Biretta, J. A. +3 more
We present broad- and narrow-band WFPC2 images of the nuclear dust disks and rings of five low- z elliptical galaxies hosting 3C radio sources: NGC 383 (3C 31)/NGC 382, NGC 3862 (3C 264), NGC 4261 (3C 270), UGC 12064 (3C 449), and NGC 7720 (3C 465)/NGC 7720A. We detect resolved line emission in all the disks. In NGC 383, the line emission consists…
Galaxy Morphology in the Rich Cluster Abell 2390
Saintonge, A.; Hutchings, J. B.; Schade, D. +1 more
We have analyzed images of the field of Abell 2390 obtained with the Canada-France-Hawaii Telescope and the Hubble Space Telescope. The analysis fits models to bulge and disk components of several hundred galaxies, with about equal samples from the cluster and field. We also have assessed and graded asymmetries in the images. The cluster galaxies …
Identification of a strong emission line at 2.8935 µm in the spectrum of the Orion Nebula
Lucy, L. B.
A strong emission line at 2.8935µm discovered by Rubin et al. in an ISO SWS02 spectrum of the Orion Nebula is identified as the 4p3P-4s3So multiplet of OI. Line formation is due to de-excitation cascades following UV-pumping of high 3So and 3Do terms and occurs in t…
Hidden subluminous stars among the FAUST UV sources towards Ophiuchus
Bowyer, Stuart; Brosch, Noah; Almoznino, Elchanan +2 more
We present results of an analysis of a UV image in the direction of Ophiuchus, obtained with the FAUST instrument. The image contains 228 UV sources. Most of these are identified as normal early-type stars through correlations with catalogued objects. For the first time in this project we identify UV sources as such stars by selecting suitable can…