Search Publications
Spectroscopy of novae -- a user's manual
Shore, Steven N.
The spectroscopic development of classical novae is described as a narrative of the various stages of the outburst. The review highlights the multiwavelength aspects of the phenomenology and the recent developments related to structure, inhomogeneity, and dynamics of the ejecta. Special emphasis is placed on the distinct behavior of the symbiotic-…
Study of Bubble nebula using IUE high resolution spectra
Murthy, Jayant; Anand, M. Y.; Kagali, B. A.
In this paper, we have analyzed IUE high resolution spectra of the central star (BD+602522) of the Bubble nebula. We discuss velocities of the different regions along the line of sight to the bubble. We find that the Bubble nebula is younger (by a factor of 100) than the exciting star suggesting that either the bubble is expanding into an inhomoge…
MSX Observations of Diffuse UV Emission in Orion
Price, S. D.; Paxton, L. J.; Henry, R. C. +1 more
We have observed intense diffuse radiation in the UV (1400 Å - 2600 Å) from three fields around M42 in Orion. Intensities of 20000 photons cm-2 sr-1 s-1 Å-1 were observed to the east and west of M42 with 8000 photons cm-2 sr-1 s-1 Å-1 south of the nebula. Enhanced emission, perhaps associated with a nearby complex of molecular clouds observed in C…
Classification of ultraviolet stellar spectra using artificial neural networks
Gulati, R. K.; Gupta, Ranjan; Gothoskar, Pradeep +1 more
Scheme based on the artificial neural networks (ANNs) trained with multi-layer back propagation using single level network for classifying ultraviolet spectra in the IUE Low-Dispersion Spectra Reference Atlas is presented. We compare the classification results obtained from single-level network with the one from multi-level neural tree network. Bo…
The Be star phenomena. II - Spectral formation and structure of envelopes
Hirata, R.; Kogure, T.
The mechanisms of formation of the continuum and line spectra of Be stars and the morphology of their cool and hot envelopes are discussed in a review of recent theoretical and observational studies, supplementing the statistical evaluation of Kogure and Hirata (1982). Topics examined include the rapid rotation of Be stars, envelope dynamics, radi…
CA II K emission in Canopus.
Bappu, M. K. V.; Mekkaden, M. V.; Rao, N. K.
The changes in the Ca II K line profile of the F0 supergiant Canopus have been studied from the high dispersion coude spectrograms obtained since 1975. The emission in the core of the line is variable in a timescale of few days. Similar activity seems to be occurring in Mg II h and k lines also. This is attributed to the variability in the appeara…
I.U.E. observation of the CO molecule towards PSI Per (B5 Ve) and its implication.
Krishna Swamy, K. S.; Tarafdar, S. P.
IUE Observations of Circumstellar Lines and Mass Loss from a B-Star
Tarafdar, S. P.; Vardya, M. S.; Krishna-Swamy, K. S.