Central Bureau for Astronomical Telegrams
IAUC 5793: N Aql 1993; V1974 Cyg; N Oph 1993
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Circular No. 5793
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
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
MARSDEN@CFA or GREEN@CFA (.SPAN, .BITNET or .HARVARD.EDU)
NOVA AQUILAE 1993
S. J. Austin and S. G. Starrfield, Arizona State University;
and R. M. Wagner, Ohio State University, report: "Optical spectrograms
of Nova Aql 1993 were obtained with the Perkins 1.8-m telescope
and CCD spectrograph on May 17.35 UT. The spectra (range
330-870 nm, resolution 1.2 nm) exhibit strong permitted emission
lines due to the Balmer series of hydrogen; Fe II (multiplets 37,
38, 42, 48, 49, 73, and 74); O I 777.4 and 844.6 nm; Ca II (H, K,
and the infrared triplet); Na D; and Mg II 823.2 nm. Many of these
lines show P-Cyg profiles. The H-alpha emission line profile is
very asymmetric to the blue side of line center. The spectra confirm
the identification as a 'Fe II class' nova in the early
postmaximum phase of its development."
V1974 CYGNI
P. Rafanelli and L. Rosino, Department of Astronomy, University
of Padua, report: "CCD spectra of the 'neon nova' V1974 Cyg (N
Cyg 1992) obtained on Mar. 19 and Apr. 21 with the 1.82-m telescope
at Ekar (Asiago) show that the nova is now in a stage of very high
ionization with outstanding nebular lines of [Ne V] 334.6, 342.6
nm; [Ne III] 386.9, 396.8 nm; [Ne IV] 472.0 nm; and [O III] 436.3,
495.9, 500.7 nm. The intensities of these lines, relative to H-
beta, were on Mar. 19 several times higher than H-beta (6.4 x
10E-12 erg cmE-2 sE-1), ranging from a maximum of about 49 for [Ne
V] at 342.6 nm to a minimum of nearly 2.0 times H-beta for [Ne IV]
at 472.0 nm. Many other lines from ions of high ionization potential
are due to He II 468.6 nm, [Ne II] 575.5 nm, [Fe VI], and [Fe
VII] 608.7 nm. The following coronal lines have also been
observed: [Fe XIV] 530.3 nm, [A X] 553.5 nm, [Fe X] 637.5 nm, and
very likely [Fe XI] 789.2 nm. Nebular and coronal lines are
presently strengthening relative to H-beta, while the relative
intensities of permitted lines of lower ionization potential (N II, He
I) are slowly fading. The line intensity ratio H-alpha/H-beta was
nearly 3 in March and April."
NOVA OPHIUCHI 1993
Further visual magnitude estimates (cf. IAUC 5777): Apr. 29.72
UT, 11.5 (A. F. Jones, Nelson, N.Z.); May 1.05, 11.7 (L. Szentasko,
Budapest, Hungary); 11.95, 12.9 (Szentasko); 12.95, 13.0 (Szentasko);
13.48, 12.6 (Jones); 15.23, 12.9 (W. G. Dillon, Missouri City, TX).
1993 May 17 (5793) Daniel W. E. Green
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