Electronic Telegram No. 852
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
CBAT@CFA.HARVARD.EDU (science)
URL http://cfa-www.harvard.edu/iau/cbat.html


V1280 SCORPII
     U. Munari, Istituto Nazionale di Astrofisica, Padova Astronomical
Observatory; and P. Valisa, G. Dalla Via, and S. Dallaporta, "Asiago
Novae and Symbiotic stars" (ANS) Collaboration, write that, as part of
the spectroscopic and photometric (photoelectric and CCD) monitoring
that the ANS Collaboration is performing on V1280 Sco (Nova Sco 2007),
the most recent spectra obtained on Feb. 20.24 UT (range 385-732 nm,
dispersion 0.17 nm) show that the nova has concluded the pre-maximum
phase, characterized by a pure-absorption spectrum, and has eventually
turned to that type of spectrum that is more typical for a classical
nova.  The spectrum is now completely dominated by a rich forest of
strong permitted emission lines that display deep P-Cyg profiles.  No
appreciable nebular emission lines are visible.  The strongest emission
lines are those of Ca II H and K, the hydrogen Balmer series, the Na I
D doublet, and Fe II 42, 49, and 74.  The nova therefore belongs to the
Fe II type.  On average, the displacement of the P-Cyg absorptions from
the emission components is 595 km/s, and the FWHM of absorption and
emission components is 425 and 640 km/s, respectively (values corrected
for the instrumental resolution).  The absolute flux of the H_beta
emission component is 1.2 x 10**(-10) erg cm**(-2) s**(-1) A**(-1), and
the H_alpha:H_beta emission ratio is 3.2.  The maximum brightness was
reached on Feb. 16; on Feb. 16.19 UT, Munari et al. measured B = 4.10
and V = 3.79.  Their last measurement on Feb. 20.19 gives B = 5.90, V =
4.83, R_c = 4.38, and I_c = 3.90.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
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                         (C) Copyright 2007 CBAT
2007 February 20                 (CBET 852)               Daniel W. E. Green