TCP J17541747-2942531: new transient (14.9 mag) in Sagittarius

SPK
Affiliation
Association Française des Observateurs d'Étoiles Variables (AFOEV)
Wed, 10/24/2018 - 07:38

Discovery details:
R.A. 17h54m17.47s, Decl. -29°42'53.1" (J2000.0)
2018 October 23.9179 UT, 14.9 mag (CCD, unfiltered)
Discoverers: Cristóvão Jacques, João Ribeiro de Barros, Eduardo Pimentel, Paulo Renato Holvorcem (SONEAR Observatory, Oliveira, Brazil)

2018 10 23.91791 UT
Discovered by C. Jacques, J. Barros, E. Pimentel, P. Holvorcem, on behalf of the Brazilian Transient Search – BraTS – at SONEAR Observatory, Oliveira, Brazil with three frames with 10 seconds exposure using an astrograph 11"f/2.2 + CCD camera under limiting mag = 16.5. Nothing is visible at this location on the previous frame (limit mag = 16.0) taken on 2018 October 21.914 UT.

2018 10 24.29 UT
Also reported as AT 2018hnj by the discoverers: https://wis-tns.weizmann.ac.il/object/2018hnj
An OGLE II. VI photometry of Galactic Bulge (Udalski+, 2002) catalogue source (position end figures 17.47s, 53.3"; V= 20.8, I= 19.0 mag) is 0.2" south of the transient's reported position.
Nothing was detected by the ASAS-SN Sky Patrol (Shappee et al. 2014ApJ...788...48S and Kochanek et al. 2017PASP..129j4502K) since 2013 Apr. 4; latest available observation is 2018 Oct. 7.0607 UT, gmag. fainter than 15.1; complete 'light curve' at
https://asas-sn.osu.edu/light_curves/fe4b7850-e9d3-4412-adb1-94623c7f8b…
--- Patrick Schmeer (Saarbrücken-Bischmisheim, Germany)

http://www.cbat.eps.harvard.edu/unconf/followups/J17541747-2942531.html

*** Spectroscopy and multiband photometry are urgently required. ***

Clear skies,
Patrick

SPK
Affiliation
Association Française des Observateurs d'Étoiles Variables (AFOEV)
Red dwarf flare?

Negative observations (Oct. 24.4 UT) by Seiichiro Kiyota (see above) and Róbert Fidrich indicate that TCP J17541747-2942531 may have been a flare of the above mentioned OGLE II source (V-I = +1.8).

Patrick Schmeer (SPK)

FRF
Affiliation
Magyar Csillagàszati Egyesület, Valtózocsillag Szakcsoport (Hungary) (MCSE)
Nothing visible on 2x60s R filter images

2x60s stacked image using R filter with T30 at the Siding Spring facility of itelescope.net.
Nothing visilbe at the given position.
2018 10 24.4455UT (See attached image.)

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