[vsnet-obs 71376] Re: PNV J18441516-1732310 (by AAX)

Wolfgang Renz wr-astro at kabelbw.de
Tue Oct 11 13:50:41 JST 2011


Hello Alexandre

I severely doubt that its a N. Probably not even a DN. Its maybe just a Mira star
with an amplitude of 3-4 mag in the visual band and a period close to one year
(that might have helped that it wasn't discovery up to now).

Why ? This star is present in all major cats that are available at CDS/VizieR:
Mean Position from major accurate astrometric cats:
                 18 44 14.959 -17 32 33.58 (J2000)
_r    _x     _y   _RAJ2000     _DEJ2000     Name                   Epoch        B     B1    B2    V     R1    R2    I     J    H    K   
 "     "     "   h:m:s        d:m:s                                            mag   mag   mag   mag   mag   mag   mag   mag  mag  mag   
0.25 +0.20 -0.15 18 44 14.973 -17 32 33.73 USNO-B1 0724-0935467   1972.0             17.19 15.97       13.56 14.58  9.02  
0.21 -0.02 -0.21 18 44 14.958 -17 32 33.79 USNO-A2 0675-29230715  1980.907               13.5             10.5  
0.17 +0.16 +0.04 18 44 14.970 -17 32 33.54 GSC2.2 S303222010468   1982.554        16.05
0.17 +0.16 +0.04 18 44 14.970 -17 32 33.54 GSC2.3 SA7C010468      1982.554        16.05                             8.78               
0.26 -0.25 +0.05 18 44 14.941 -17 32 33.53 NOMAD1 0724-0975415 (YB) -          14.75             13.93                                 
0.15 -0.13 +0.07 18 44 14.950 -17 32 33.51 UCAC3 145-364066       1986.15/1980.90                    16.52                             
0.24 -0.23 +0.07 18 44 14.943 -17 32 33.51 GSC2.2 S3032220120001  1996.699                       13.57    14.63                        
0.24 -0.23 +0.08 18 44 14.943 -17 32 33.50 GSC2.3 SA7C010468      1996.699     16.83             13.57    14.63    10.12               
0.13 +0.11 -0.07 18 44 14.966 -17 32 33.65 2MASS 18441496-1732336 1998-05-04.4                                           5.53 4.78 4.26
0.02 +0.02 -0.01 18 44 14.960 -17 32 33.59 DENIS J184414.9-173233 1998-05-21.3                                     10.08 5.27      3.38
0.02 +0.02 +0.01 18 44 14.960 -17 32 33.57 CMC14 184414.9-173233  2002-09-03                              14.38                         
3.50 -4    -2    18 44 14.8   -17 32 36    IRAS 18413-1735          -          {        12um:4.7(5)Jy   25um:1.9(2)Jy}
0.21 -0.2  -0.0  18 44 14.94  -17 32 33.6  AKARI 1844149-173233     -          {S9W:4.67(5)Jy   L18W:2.3(6)Jy        }
Its for sure a relative red star, pretty bright in NIR, very bright in MIR. No Rosat
etc detection at short wavelengths.
The only filtered obs at the TOCP follow up page:
http://www.cbat.eps.harvard.edu/unconf/followups/J18441516-1732310.html
by Seiichiro Kiyota gives B=13.00, V=11.64, R=10.14, I=7.62 that does confirm
that its a red star and not nearly as blue as one would expect if it would be a DN.

The "outburst" obs are especially bright, because nearly all obs at the CBAT
TOCP follow-up page were made unfiltered. So it might be just an other flavour
of the common "red star oberseved unfiltered" issue. But this time the star is at
least a variable as the ASAS LC does show:
http://www.astrouw.edu.pl/cgi-asas/asas_variable/184415-1732.6,asas3,0,0,500,0,0

The star might also be NSV 11264 (= HV 09513 = AN 766.1936, amplitude
12.3 to < 16p):
http://www.sai.msu.su/gcvs/cgi-bin/co-h.cgi?coor=18+44+14.959+-17+32+33.58
http://www.sai.msu.su/groups/cluster/gcvs/cgi-bin/search.cgi?search=NSV+11264
http://www.aavso.org/vsx/index.php?view=detail.top&oid=49888
as the amplitude and range would fit pretty well to the above data.
But the NSV 11264 tag is currently assigned to the 9.9 mag V star BD-17 5304
(= 2MASS J18441648-1731549  = PPM 719650) that is 44.4" to the NNE at
18 44 16.48 -17 31 54.9 (J2000):
http://simbad.u-strasbg.fr/simbad/sim-id?Ident=BD-17%205304&submit=submit
If the coords in the NSV would be correct, it could be just a close companion
of the BD star. It wouldn't be the first time that the original identification for a
NSV star to a bright star is incorrect. But I couldn't access any of the given
refs to verify this.

Clear skies
 Wolfgang

-- 
Wolfgang Renz, Karlsruhe, Germany


 
----- Original Message ----- 
> From: "Alexandre Amorim" <costeira1 at yahoo.com>
> To: <vsnet-obs at ooruri.kusastro.kyoto-u.ac.jp>
> Sent: Tuesday, October 11, 2011 3:18 AM
> Subject: [vsnet-obs 71375] PNV J18441516-1732310 (by AAX)
> 
> PNV J18441516-1732310  20111009.9375 11.5 AAX
> PNV J18441516-1732310  20111010.9444 11.4 AAX
> 
> AAX = Alexandre Amorim, Florianopolis, Brazil
> 
> I think that this star is ASAS 184415-1732.6 and another four activities were detected by ASAS.
> 
> More information at website: http://www.costeira1.astrodatabase.net/nova/pnv18441516.htm
> 
> ********* Alexandre Amorim ***********
> *        Estacao  Costeira1          *
> *         Florianopolis/SC           *
> *          http://go.to/c1           *
> **************************************



----- Original Message ----- 
> From: "Alexandre Amorim"
> To: <Aavso-discussion at aavso.org>
> Sent: Monday, October 10, 2011 11:02 PM
> Subject: [AAVSO-DIS] Enc: PNV J18441516-1732310
> 
>>> De: Alexandre Amorim
>>> Assunto: PNV J18441516-1732310
>>> Para: cbatiau at eps.harvard.edu, cbat at iau.org
>>> Cc: "Alexandre Amorim"
>>> Data: Domingo, 9 de Outubro de 2011, 23:37
>>> PNV J18441516-1732310
>>> Visual estimate
>>> 
>>> 2011 October 9.937 UT, 11.5 (A. Amorim, Florianopolis, Brazil)
>>> 
>>> Using 0.18-m reflector, magnitude source: ASAS-3. Chart: AAVSO 5646mfp
>>> 
>>> Possibly this star is ASAS 184415-1732.6 and another four activities were
>>> detected by ASAS.
>>> More information at website
>>> http://www.costeira1.astrodatabase.net/nova/pnv18441516.htm
>> 
>> ********* Alexandre Amorim ***********
>> *        Estacao  Costeira1          *
>> *         Florianopolis/SC           *
>> *          http://go.to/c1           *
>> **************************************
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://ooruri.kusastro.kyoto-u.ac.jp/pipermail/vsnet-obs/attachments/20111011/d23b70e3/attachment.htm>


More information about the vsnet-obs mailing list