Sziasztok!
Brian Skiff azt írja, hogy a csillag már az 50-es években is látszott a
POSS-I lemezeken (vörösben), ami alapján szerinte ez nem egy sima nóva.
A színkép alapján azt gondolja, hogy egy szimbiotikus változó
kitöréséről van szó. Ettől persze a történet nem lesz kevésbé érdekes,
hiszen szimbiotikus változókból még kevesebb van mint a galaktikus
nóvákból...
* * *
Date: Mon, 14 May 2012 14:52:24 -0700
From: Brian Skiff
Subject: Re: [AAVSO-DIS] PNV J18110375-2717276
The fact that this star is present on the POSS-I red plate
from the 1950s, and subsequent data sources since then (it is an
IRAS, MSX, AKARI, and WISE source, for instance) means this simply
cannot be an ordinary nova. The recent spectrum looks like a
symbiotic star in outburst. This does not make the event less
interesting! There are fewer known symbiotic stars than galactic
novae.
various aliases:
2MASS J18110370-2717294 18 11 03.70 -27 17 29.4 (J2000)
GSC-2.3 S9TN078861
DENIS J181103.7-271730
IRAS 18079-2718 12mu flux = 0.68 Jy
MSX6C G004.2275-04.0406 A-band flux = 0.62 Jy
AKARI J1811037-271728
WISE J181103.69-271729.3 18 11 03.70 -27 17 29.4
The 2MASS and WISE coordinates are identical within the round-off
errors, so either of those are the preferred coordinates for the star,
if only because neither will be affected by crowding problems, as will
be the case in the visible. These positions were obtained ten years
apart.
The IRAS 12-micron and MSX ´A´ passbands are nearly the same,
which is why the fluxes are similar within errors (the data were
taken ~15 years apart). The thing is blazing bright in the WISE data
(partly saturated in the two shorter wavelengths), which mainly means
it is both cool and dusty. The WISE ´W3´ passband should have similar
flux if converted to linear units. All this mainly tells you the thing
has been there a long time, whereas an ordinary nova would not have
been present in any of these surveys irrespective of wavelength.
\Brian
----- End forwarded message -----
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Fidusz (FIDRICH Robert)
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