First high resolution ultraviolet (HST/STIS) and supporting optical spectroscopy (CHIRON/SMARTS, HRS/SALT) of V1369 Cen = Nova Cen 2013
ATel #6413; S. N. Shore (Univ. of Pisa, INFN-Pisa); G. J. Schwarz (AAS); F. M. Walter (SUNY-SB); S. Crawford (SAAO); P. A. Woudt (Univ. of Cape Town); R. E. Williams (STScI); E. Mason (INAF-OA Trieste); L. Izzo (Univ. of Rome - La Sapienza); K. L. Page, J. P. Osborne (Leicester); J-U Ness (ESA); S. Starrfield (ASU); C. E. Woodward (Univ. of Minnesota) ; P. Vaisanen, F. Marang, L. Crause, L. Tyas (SAAO)
on 24 Aug 2014; 00:35 UT
Distributed as an Instant Email Notice Novae
Credential Certification: S. N. Shore (email@example.com)
Subjects: Optical, Ultra-Violet, Request for Observations, Nova
We report the preliminary results of the first ultraviolet
observations of the classical nova V1369 Cen (Nova Cen 2013) with the Space
Telescope Imaging Spectrograph (STIS) aboard the Hubble Space
Telescope. High resolution spectra (1141-3072A) were obtained with
HST/STIS on 2014 Aug. 12.3 UT using the E140H (R ~ 100000) and
E230M gratings (R ~ 30000) with nearly simultaneous groundbased
optical spectra obtained with CHIRON at CTIO (R ~80000)
4578-8761A) and the High Resolution Spectrograph on the
Southern African Large Telescope (SALT) (R ~ 80000, Bramall, D.G. et al., 2012, Proc. SPIE, 8446, 84460-A1).
The UV displays many similarities to the V339 Del spectra
from 2014 Apr. (ATel#6088) and we report here integrated fluxes
(not corrected for extinction) for the same lines for comparison:
N V 1240 (5.3E-10), O I 1302 (9.4E-12), C II 1334
(1.3E-10), O V] 1371 (1.4e-11), C II 1335 (1.3E-10), O IV 1402
(1.2E-10, complex), N IV] 1486 (1.7E-10), C IV 1550 (9.0E-10), He II
1640 (8.6E-11), O III] 1665 (7.3E-11), N IV] 1718 (1.7E-11), N III]
1751 (3.4E-10), C III] 1909 (6.0E-10), C III 2296 (1.1E-11), C II 2324
(1.1E-10), O II 2470 (2.7E-11), Mg II 2800 (5.4E-11), C II 2836
(2.1E-11). All units are erg/s/cm^2. The Ly-alpha, N V 1240, and C IV 1550
resonance lines display P Cyg absorption troughs from about -1500 to
-1800 km/s. The FWZI of the lines is ~ 3000 km/s.
In general, the profiles are not strictly symmetric, the blueshifted emission is
systematically stronger. The individual ions have distinctive profiles ranging from nearly
featureless and flat-topped for low ionization to saddle-shaped profiles,
with peaks at +/-500 km/s, for the highest ions. In the
optical, the resonance lines [Fe VII] 3759, 5156A (poss. blend with [Fe VI] 5146A), 5276, 6087A,
and [Ca V] 5309, 6387A are detected with similar profiles to the excited state lines He II
1640, 4686A. Fine structure is seen on all intercombination lines, especially
N IV] and C III], at the same velocities with widths of about 100 km/s.
The [F III] resonance lines are likely present at 2934A. Ar III] 7135A
is present with a similar profile, like O III] 1660, 1667A. O II] 2470A
is also present with a profile similar to [O I] 6300, 6364A.
Emission lines are detected at 1814,1602, and 1575A. These lines were not
detected in V339 Del (CO-type) but were present in V959 Mon
(ONe-type). The [Ne III] 3869, 3967A lines are clearly present in
the SALT spectrum. The Al III 1854, 1862A resonance lines are absent
but two unidentified lines, 1846, 1861A (not Al III) are detected that were not present
in V339 Del STIS spectra (but were reported as unidentified in RR Tel
by Aufdenberg, J. P.1993, ApJS, 87, 337).
The UV interstellar spectrum is very rich, including Ly-alpha. C I-III,
N I, O I, Si II-IV, Fe II, Mg I/II, Si I/II, Al II. Using the C I
1260 and 1277, Na I 5889 (from the CHIRON spectra), Mg I 2852, and C II
1335 to compare with the LAB 21 cm H I profile,
the range covered by the absorption is about 15% of the total column in
H I from the 21 cm' this gives E(B-V) ~ 0.1 and N_H ~ 8E20/cm^2 (using
Diplas A. & Savage B. D. 1994, ApJS, 93, 211). Scaling to V339 Del (E(B-V) ~ 0.2), the flux
ratio is ~3 throughout the UV, suggesting a distance of ~ 2.4 kpc. The
dereddened integrated flux (1150-3000A) is 1.2E-8 erg/s/cm^2.
Observations at high resolution below 4000 A, in particular around the
[Ne V] 3345, 3425A lines, is strongly encouraged.
Some of the observations reported in this ATel were obtained with the Southern African Large Telescope (SALT) under DDT program 2014-1-DDT-002.