LT/SPRAT spectroscopic classification of Gaia microlensing event candidates (part 2)
ATel #13742; Pawel Zielinski, Ilknur Gezer, Mariusz Gromadzki, Lukasz Wyrzykowski, Nada Ihanec, Katarzyna Kruszynska, Krzysztof Rybicki, Marco C. Lam (Astronomical Observatory, University of Warsaw), Marius Maskoliunas, Erika Pakstiene (Vilnius University), Andrzej Pigulski, Przemyslaw Mikolajczyk (University of Wroclaw) Simon Hodgkin (Institute of Astronomy, University of Cambridge)
on 19 May 2020; 17:06 UT
Credential Certification: Pawel Zielinski (pzielinski.astro@gmail.com)
Subjects: Optical, Microlensing Event, Transient, Variables
Referred to by ATel #: 13992
We report on spectroscopic observations of next 10 candidates for microlensing events detected primarily by the Gaia Science Alerts programme (http://gsaweb.ast.cam.ac.uk/alerts). Spectra were taken with 2-m Liverpool Telescope (LT, Steele et al. 2004, Proc. SPIE, vol. 5489, 679) equipped with the Spectrograph for the Rapid Acquisition of Transients (SPRAT, Piascik et al. 2014, Proc. SPIE, vol. 9147, id. 91478H) in the optical part of electromagnetic window (400-800 nm) and low-resolution mode (R~350). The observations were gathered between 2020-04-08 and 2020-04-20. The links provided as IAU names of the events lead to the Transient Name Server pages with detailed information.
Gaia Name | IAU Name | RA (J2000) | Dec (J2000) | Discovery date | Discovery G mag | Spectrum date | Class
----------|------------|-------------|--------------|----------------|-----------------|---------------|------------------
Gaia20blb | AT 2020evf | 18:44:03.09 | +00:29:25.58 | 2020-03-19 | 15.18 | 2020-04-08 | star/ULENS (1)
Gaia19dqg | AT 2019odq | 18:37:20.92 | -03:28:17.40 | 2019-08-19 | 14.88 | 2020-04-08 | star/ULENS (2)
Gaia19fhn | AT 2019vsh | 19:01:56.33 | +01:33:00.00 | 2019-11-27 | 16.42 | 2020-04-08 | star/ULENS (3)
Gaia19dqm | AT 2019odw | 19:22:04.22 | +11:17:35.30 | 2019-08-20 | 15.20 | 2020-04-08 | star/ULENS (4)
Gaia20bkw | AT 2020eva | 19:33:17.47 | +17:22:12.18 | 2020-03-20 | 14.09 | 2020-04-09 | Be/Ae star (5)
Gaia20blv | AT 2020ewo | 19:29:28.28 | +16:37:15.35 | 2020-03-20 | 16.33 | 2020-04-09 | Be/Ae star (6)
Gaia20blp | AT 2020ewk | 20:29:52.68 | +37:18:29.30 | 2020-03-22 | 15.20 | 2020-04-09 | Be star (7)
Gaia20bwp | AT 2020htp | 18:48:07.44 | -06:10:41.12 | 2020-04-18 | 15.92 | 2020-04-20 | Be star (8)
Gaia20bbn | AT 2020drc | 18:35:38.85 | -06:48:16.34 | 2020-02-26 | 15.56 | 2020-04-20 | Be star (9)
Gaia20bml | AT 2020faw | 21:18:27.99 | +50:52:21.65 | 2020-03-25 | 15.48 | 2020-04-20 | Be star (10)
Notes:
(1) absoption lines only visible, GK-type star, microlensing event candidate.
(2) absorption lines of Balmer series, probably TiO bands visible, K-type star, microlensing event candidate.
(3) no obvious emission features in Balmer series, probably Mg II triplet visible, microlensing event candidate.
(4) absorption lines of Balmer series and Na lines, K-type star, microlensing event candidate.
(5) strong emission in Halpha, maybe also Hbeta line, reddened Be/Ae star.
(6) Halpha line in emission, reddened Be/Ae star.
(7) broad emission Halpha profile, most probably reddened Be star.
(8) strong emission in Halpha, most probably reddened Be star.
(9) Balmer lines in emission, no TiO bands visible, reddened Be star.
(10) Halpha line in emission, no TiO bands visible, reddened Be star.
Acknowledgments. We thank LT Support Astronomers for help with observations and data reduction. Observations were carried out under OPTICON programmes XOL19B02 and XOL20A02 (PI: P. Zielinski). This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 730890. AP and PM acknowledge support provided by the Polish National Science Center (NCN) through grant 2016/21/B/ST9/01126. The Liverpool Telescope is operated on the island of La Palma by Liverpool John Moores University in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias with financial support from the UK Science and Technology Facilities Council. We acknowledge ESA Gaia, DPAC and the Photometric Science Alerts Team (http://gsaweb.ast.cam.ac.uk/alerts).
