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IAUC 5015: V3890 Sgr; zeta Oph

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                                                  Circular No. 5015
Central Bureau for Astronomical Telegrams
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Telephone 617-495-7244/7440/7444 (for emergency use only)
TWX 710-320-6842 ASTROGRAM CAM     EASYLINK 62794505

     K. Mukai, Center for EUV Astrophysics, University of California
at Berkeley; S. R. Rosen and K. Supelli, Mullard Space Science
Laboratory, University College, London; and D. Allen, Anglo-Australian
Observatory, report:  "We have obtained spectra of V3890 Sgr (cf.
IAUC 5010) with the Anglo-Australian Telescope on May 14, using the
Faint Object Red spectrograph in the red (520-1100 nm) and the RGO
spectrograph with Image Photon Counting System in the blue (3 separate
wavelength regions covering 340-500 nm with small gaps).  The
spectra are dominated by permitted emission lines of hydrogen and
helium.  In addition, we find O III 344.4-nm, N III 463.4/464.0-nm,
[Fe XIV] 530.3-nm, [Ar X] 553.3-nm, [Fe X] 637.4-nm, O VI 683.0-nm,
O I 777.2-nm, [Fe XI] 787.1-nm, O I 844.6-nm, and [S III] 906.9-nm.
There is a strong similarity between these spectra and that of AS
295B (Herbig and Hoffleit 1975, Ap.J. 202, L41).  We detect about
15 further lines in the blue, which may be due to Fe II or O II.
H-beta is obviously broader than He II 468.6-nm (FWHM = 0.4 nm); a
single Gaussian fit of the former gives an FWHM of 0.6 nm, although
a core and wing structure is more likely.  We note that [Fe VII]
608.5-nm reported by Wagner et al. (IAUC 5006) is absent in our
spectra, showing that V3890 Sgr has progressed to a higher ionization
state.  Further spectroscopic monitoring would clearly be useful."
     Visual magnitude estimates (cf. IAUC 5007):  May 7.11 UT, 10.3
(P. Schmeer, Bischmisheim, W. Germany); 7.17, 9.3 (A. Pereira,
Linda-a-Velha, Portugal); 15.03, 11.4 (Schmeer); 15.87, 11.7 (A.
Pearce, Scarborough, W. Australia); 16.87, 11.9 (Pearce); 17.04,
12.0 (Schmeer).

     E. Kambe, and H. Ando, National Astronomy Observatory of Japan;
and R. Hirata, Kyoto University, communicate:  "We discovered the
reappearance of the weak double emission components in H-alpha and
He I (667.8 nm) of zeta Oph on May 9 and 15 using the CCD camera
attached to the coude spectrograph of the Okayama 1.88-m reflector.
The last emission phase was in 1980 (Ebbets 1981, P.A.S.P. 93, 119).
The emission components seem to strengthen in our observation.  The
short time variation in the He I absorption profile is remarkable."

1990 May 17                    (5015)             Daniel W. E. Green

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