2022A&A...657A..18R


Query : 2022A&A...657A..18R

2022A&A...657A..18R - Astronomy and Astrophysics, volume 657A, 18-18 (2022/1-1)

Single-lens mass measurement in the high-magnification microlensing event Gaia19bld located in the Galactic disc.

RYBICKI K.A., WYRZYKOWSKI L., BACHELET E., CASSAN A., ZIELINSKI P., GOULD A., CALCHI NOVATI S., YEE J.C., RYU Y.-H., GROMADZKI M., MIKOLAJCZYK P., IHANEC N., KRUSZYNSKA K., HAMBSCH F.-J., ZOLA S., FOSSEY S.J., AWIPHAN S., NAKHARUTAI N., LEWIS F., OLIVARES F.E., HODGKIN S., DELGADO A., BREEDT E., HARRISON D.L., VAN LEEUWEN M., RIXON G., WEVERS T., YOLDAS A., UDALSKI A., SZYMANSKI M.K., SOSZYNSKI I., PIETRUKOWICZ P., KOZLOWSKI S., SKOWRON J., POLESKI R., ULACZYK K., MROZ P., IWANEK P., WRONA M., STREET R.A., TSAPRAS Y., HUNDERTMARK M., DOMINIK M., BEICHMAN C., BRYDEN G., CAREY S., GAUDI B.S., HENDERSON C., SHVARTZVALD Y., ZANG W., ZHU W., CHRISTIE G.W., GREEN J., HENNERLEY S., McCORMICK J., MONARD L.A.G., NATUSCH T., POGGE R.W., GEZER I., GURGUL A., KACZMAREK Z., KONACKI M., LAM M.C., MASKOLIUNAS M., PAKSTIENE E., RATAJCZAK M., STANKEVICIUTE A., ZDANAVICIUS J. and ZIOLKOWSKA O.

Abstract (from CDS):

Context. Microlensing provides a unique opportunity to detect non-luminous objects. In the rare cases that the Einstein radius θE and microlensing parallax πE can be measured, it is possible to determine the mass of the lens. With technological advances in both ground- and space-based observatories, astrometric and interferometric measurements are becoming viable, which can lead to the more routine determination of θE and, if the microlensing parallax is also measured, the mass of the lens. Aims. We present the photometric analysis of Gaia19bld, a high-magnification (A ≃ 60) microlensing event located in the southern Galactic plane, which exhibited finite source and microlensing parallax effects. Due to a prompt detection by the Gaia satellite and the very high brightness of I = 9.05 mag at the peak, it was possible to collect a complete and unique set of multi-channel follow-up observations, which allowed us to determine all parameters vital for the characterisation of the lens and the source in the microlensing event. Methods. Gaia19bld was discovered by the Gaia satellite and was subsequently intensively followed up with a network of ground-based observatories and the Spitzer Space Telescope. We collected multiple high-resolution spectra with Very Large Telescope (VLT)/X-shooter to characterise the source star. The event was also observed with VLT Interferometer (VLTI)/PIONIER during the peak. Here we focus on the photometric observations and model the light curve composed of data from Gaia, Spitzer, and multiple optical, ground-based observatories. We find the best-fitting solution with parallax and finite source effects. We derived the limit on the luminosity of the lens based on the blended light model and spectroscopic distance. Results. We compute the mass of the lens to be 1.13 ±0.03 M and derive its distance to be 5.52–0.64+0.35 kpc. The lens is likely a main sequence star, however its true nature has yet to be verified by future high-resolution observations. Our results are consistent with interferometric measurements of the angular Einstein radius, emphasising that interferometry can be a new channel for determining the masses of objects that would otherwise remain undetectable, including stellar-mass black holes.

Abstract Copyright: © ESO 2021

Journal keyword(s): gravitational lensing: micro - stars: fundamental parameters - white dwarfs - stars: neutron

Simbad objects: 7

goto Full paper

goto View the references in ADS

Number of rows : 7
N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2023
#notes
1 NAME Magellanic Clouds GrG 03 00 -71.0           ~ 6555 1
2 AT 2019dqb ev 12 37 32.560 -66 06 40.90           ~ 6 0
3 KMT-2018-BLG-0029 * 17 37 52.670 -27 59 04.92           ~ 14 0
4 EWS 2017-BLG-406 * 17 55 59.92 -29 51 47.3           ~ 7 0
5 NAME Baade Window reg 18 03.5 -30 01           ~ 586 3
6 EWS 2018-BLG-799 * 18 13 50.16 -25 29 08.6           ~ 4 0
7 NAME Galactic Bulge reg ~ ~           ~ 4012 0

To bookmark this query, right click on this link: simbad:objects in 2022A&A...657A..18R and select 'bookmark this link' or equivalent in the popup menu


2023.01.27-17:56:08

© Université de Strasbourg/CNRS

    • Contact