Search Publications
A survey of MG II H and K emission in near-solar-type stars.
Doherty, L. R.
IUE measurements of Mg II h and k emission fluxes are presented for 30 F and G stars that are on or near the main sequence and compared with Wilson's measurements of the Ca II H and K fluxes in these stars. The survey includes a large proportion of stars with very low chromospheric activity as well as 111 Tau, χ1Ori and other examples o…
X-ray emission from the cataclysmic variable PG 0834+488.
Cook, M. C.
A 5-hr observation of PG0834+488 using the EXOSAT X-ray observatory has resulted in its detection as an X-ray source. The light curve shows marginal evidence for variability but no coherent periodicities were found. The X-ray spectrum was hard, with a photon index of ≡1.36, and the low-energy absorption implied a low column density NH ≡…
HR 5637 : the unveiling of a binary.
Cottrell, P. L.; Ake, T. B., III; Noordanus, B.
HR 5637, previously classified as G1/3 Ib/II but considered composite by Bidelman and MacConnell, has been examined both photometrically and spectroscopically. The spectroscopic observations spanned the wavelength interval 1000-7000 A. Using these data in various combinations, the star is shown to be a binary with components of G2-5Ib and B8 V, wi…
Observations of Comet Crommelin. V - Anomalous hydrogen source
Wallis, M. K.; Carey, W. C.
Lyman-alpha intensities measured by IUE at various positions in the coma of Comet Crommelin are interpreted on the basis of H2O model calculations. However, the H-production on dates in March and April 1984 was significantly higher than implied by OH measurements by IUE and from the ground. Simultaneous data from the two apertures on March 30 excl…
Observations of Comet Crommelin. IV - Upper limit on the optical depth in the coma at ultraviolet wavelengths
Evans, A.; Zarnecki, J. C.; Bode, M. F. +2 more
The bright (V = 9.1) star SAO 152362 was observed with the long-wavelength (LWP) camera of the IUE satellite before and during a close approach by Comet Crommelin. No significant change in the ultraviolet spectrum of the star occurred during the encounter and an upper limit is set on the optical depth of the dust in the coma of the comet.