Gaia20fnr/AT2020ably is bright microlensing event based on LT/SPRAT and Gemini/GMOS-N spectra

ATel #14316; Zielinski P., Gezer I., Gromadzki M., Wyrzykowski L., Lam M. C., Ihanec N., Kruszynska K., Rybicki K. A. (Astronomical Observatory, University of Warsaw), Maskoliunas M., Zdanavicius J., Pakstiene E. (Institute of Theoretical Physics and Astronomy, Vilnius University), Hodgkin S. (Institute of Astronomy, University of Cambridge)
on 12 Jan 2021; 14:45 UT
Credential Certification: Pawel Zielinski (pzielinski.astro@gmail.com)

Tweet

We report on spectroscopic observations of Gaia20fnr (AT2020ably) which was detected primarily by the Gaia Science Alerts programme (http://gsaweb.ast.cam.ac.uk/alerts) on 2020-12-02 at discovery magnitude G=12.91. First spectrum were taken on 2020-12-23 with 2-m Liverpool Telescope (LT) equipped with the Spectrograph for the Rapid Acquisition of Transients (SPRAT, Piascik et al. 2014) in the optical part of electromagnetic window (400-800 nm) and low-resolution mode (R~350). The second spectrum for this target has been obtained on 2021-01-09 by using 8-m Gemini/GMOS-N instrument (Gemini Multi-Object Spectrographs, Hook et al. 2002) in long-slit mode with gratings R400 which provides resolution power of R~2000 and covers the wavelength range from 400 to 900 nm. In both spectra, we observe absorption lines of Balmer series and no clear emission is detectable. In addition, thanks to wavelength coverage of GMOS, Ca II triplet is visible. Continuum shapes and observed lines suggest spectral type F-G. Based on this, we classify Gaia20fnr as bright microlensing event. Therefore, the brightening observed in its light curve should be assigned to this phenomena. More photometric and spectroscopic data will be appreciated. The spectra and detailed information can be found here: https://www.wis-tns.org/object/2020ably.

Acknowledgments. We thank LT Support Astronomers for help with observations and data reduction. Observations were carried out under OPTICON programme XOL20B01 (PI: P. Zielinski). We also thank Gemini Support Astronomers for help with observations which were carried out under the GN-2020B-Q-318 program. (PI: I. Gezer). This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 730890. We are supported by Polish NCN DAINA grant 2017/27/L/ST9/03221 and Research Council of Lithuania grant No. S-LL-19-2. 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. This work was enabled by observations made from the Gemini North telescope, which is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation on behalf of the Gemini Observatory partnership: the National Science Foundation (United States), National Research Council (Canada), Agencia Nacional de Investigacion y Desarrollo (Chile), Ministerio de Ciencia, Tecnologia e Innovacion (Argentina), Ministerio da Ciencia, Tecnologia, Inovacoes e Comunicacoes (Brazil), and Korea Astronomy and Space Science Institute (Republic of Korea) and located within the Maunakea Science Reserve and adjacent to the summit of Maunakea. We are grateful for the privilege of observing the Universe from a place that is unique in both its astronomical quality and its cultural significance. We acknowledge ESA Gaia, DPAC and the Photometric Science Alerts Team (http://gsaweb.ast.cam.ac.uk/alerts).