[vsnet-alert 22911] Re: TCP J15472959-0532144: new transient (12.1 mag) in Libra

[Hiroyuki Maehara]

Kaneko-san reported follow-up observations of this object as follows.

object         YYYYMMDD(UT)   mag  code
TCPJ15472959-0532144 20181230.58736 135V     ShK
TCPJ15472959-0532144 20181230.58885 141Ic    ShK

R.A.: 15 47 29.84
Decl.: -05 32 18.0  (ref. UCAC4)

Observer: Shizuo Kaneko (Shizuoka, Japan)
Instruments: 61cmL (iTelescope T24) + FLI PL9000

> -----Original Message-----
> From: vsnet-alert <vsnet-alert-bounces at ooruri.kusastro.kyoto-u.ac.jp> On
> Behalf Of Patrick Schmeer pasc1312-aavso at yahoo.de via vsnet-alert
> Sent: Sunday, December 30, 2018 7:09 PM
> To: vsnet-alert at ooruri.kusastro.kyoto-u.ac.jp;
> vsnet-outburst at ooruri.kusastro.kyoto-u.ac.jp; cvnet-outburst at yahoogroups.com;
> baavss-alert at yahoogroups.com
> Subject: [vsnet-alert 22909] TCP J15472959-0532144: new transient (12.1 mag) in
> Libra
> 
> TCP J15472959-0532144  (UG:)
> 
> Discovery details:
> R.A. 15h47m29.59s, Decl. -05°32'14.4" (J2000.0)
> 2018 Dec. 29.8217 UT, 12.1 mag (CCD, unfiltered)
> Discoverer: Hideo Nishimura (Shizuoka-ken, Japan)
> 
> 2018 12 29.822 UT
> Discovered by H. Nishimura, Shizuoka-ken, Japan,
> on three frames with 30 second exposure using
> Canon EOS 6D digital camera + 200-mm f/3.2 lens
> under the limiting mag = 15, who writes nothing
> is visible at this location on a frame taken on
> 2018 Dec. 20.867 UT with limit mag.= 13 and
> there is a star (mag = 18.5) at this location.
> Also S. Kaneko, Shizuoka-ken, reports no star
> was visible on two frames (limit mag = 14.4)
> taken 2018 Dec. 28.843 UT.
> 
> 2018 12 30.12 UT
> A progenitor candidate from Gaia DR2 is 5" away
> at R.A. 15h47m29.838s, Decl. -05°32'18.10"
> (equinox J2000.0, epoch 2015.5; Gmag. 17.44,
> parallax 2.0059 ± 0.1161 mas, distance ~0.49 kpc).
> Other designations are CSS_J154729.8-053218
> (Vmag. range 16.8-17.3), USNO-A2.0 0825-08927905
> (Bmag. 18.5, Rmag. 17.2), USNO-B1.0 0844-0276155,
> PSO J154729.843-053218.154 (gmag. 18.83, rmag.
> 17.82), GSC2.3 S89H006806 (Fmag. 17.60),
> 2MASS J15472984-0532182, GALEX J154729.8-053218
> (nuv_mag. 21.9), etc.
> No previous outbursts were detected by the
> ASAS-SN Sky Patrol (Shappee et al. 2014ApJ...788
> ...48S and Kochanek et al. 2017PASP..129j4502K)
> at the transient's position between 2012 March 17
> and 2018 September 22; complete light curve at
> https://asas-sn.osu.edu/light_curves/2308153f-5f15-4fdc-a525-dababb4df431
> Patrick Schmeer (Saarbrücken-Bischmisheim, Germany)
> 
> http://www.cbat.eps.harvard.edu/unconf/followups/J15472959-0532144.html
> 
> Precise astrometry, spectroscopy, and multiband
> (and time-resolved) photometry are urgently
> required.
> 
> Clear skies,
> Patrick