Affiliation
Association Francaise des Observateurs d'Etoiles Variables (AFOEV)
Sat, 01/27/2018 - 09:35
PNV J19202580+1851180 (UG/N)
Discoverer: Yukio Sakurai (Mito, Ibaraki-ken, Japan)
RA 19h20m25.80s, DEC +18°51'18.0" (J2000.0)
2018 Jan. 26.8608 UT, 12.6 mag (CCD, unfiltered)
"2018 01 26.861 UT
Discovered by Y. Sakurai, Ibaraki-ken, Japan, on two frames with 10-s exposure using Nikon D7100 + digital
camera + 180-mm f/2.8 lens under the limiting mag = 13s, who writes that nothing is visible at this location on a frame taken on 2018 Jan. 25.861 UT. There is a star (mag.= 16.2) at 26s.32 and 23".6."
http://www.cbat.eps.harvard.edu/unconf/followups/J19202580+1851180.html
Spectroscopy and precise astrometry are urgently required; time-resolved photometry is also
recommended.
Clear skies,
Patrick
2018. Jan 28.249UT:
Nothing visible at the position given by Sakurai-san down to 13.6TG on 9x45s + 1x30s + 8x10s stacked images made with Canon EOS 1000D DSLR camera and Zeiss Sonnar 180mm f/2.8 telephoto lens.
Maybe there is something around 13.5m (TG) at position near 19 20 21.77 +18 52 43.4, but very uncertain - marked whit yellow -, but that is ~1.5' (90-100") distance from the given position.
Further follow-up images with larges instruments are required.
There is a prominent 2MASS source at 19 20 25.6 +18 51 12 (as measured off the Simbad jpeg view) which appears to have a faint positive counterpart in the Simbad DSS jpeg view perhaps mag 18-19(??). This may well have nothing to do with Y. Sakurai's PNV but is very close by.
Steve
V120sec and Ic60sec images taken with iT5 (New Mexico) on Jan 28.534UT, in moderate twilight show no obvious sources at Y. Sakurai's reported position nor at R. Fidrich's possible nearby faint TG detection as kindly offered in this thread. I would call it <15.0V (fainter than 15.0V) at both positions and no dectection(s) down to roughly 13.5 in Ic. Interestingly, about 3.5 arc-min NNW, there is a very bright detection in Ic at (VPHOT-measured position) 19 20 14.1 +18 53 07.8. It is also a very feeble detection (mag15:) on the V image. Sakurai's exposures were (unfiltered) ... was it this (known) Ic-bright source he picked up ? . Positions don't match well with the originalPNV report.
kind regards,
Steve