Uncovering the invisible: A study of Gaia18ajz, a candidate black hole revealed by microlensing

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A_____%2F25%3A00617099" target="_blank" >RIV/67985815:_____/25:00617099 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/68407700:21230/25:00381937 RIV/47813059:19630/25:A0000480 RIV/00216208:11320/25:10511212

Výsledek na webu

<a href="https://hdl.handle.net/11104/0365922" target="_blank" >https://hdl.handle.net/11104/0365922</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1051/0004-6361/202451046" target="_blank" >10.1051/0004-6361/202451046</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Uncovering the invisible: A study of Gaia18ajz, a candidate black hole revealed by microlensing

Popis výsledku v původním jazyce

Context. Identifying black holes is essential for our understanding of the development of stars and can reveal novel principles of physics. Gravitational microlensing provides an exceptional opportunity to examine an undetectable population of black holes in the Milky Way. In particular, long-lasting events are likely to be associated with massive lenses, including black holes. Aims. We present an analysis of the Gaia18ajz microlensing event reported by the Gaia Science Alerts system. Gaia18ajz is a long-timescale event exhibiting features indicative of the annual microlensing parallax effect. Our objective is to estimate its lens parameters based on the best-fitting model. Methods. We used photometric data obtained from the Gaia satellite and terrestrial observatories to investigate a variety of microlensing models and calculate the most probable mass and distance to the lens, taking into consideration a Galactic model as a prior. Subsequently, we applied a mass-brightness relation to evaluate the likelihood that the lens is a main sequence star. We also describe the DarkLensCode (DLC), an open- source routine that computes the distribution of probable lens mass, distance, and luminosity employing the Galaxy priors on stellar density and velocity for microlensing events with detected microlensing parallax. Results. We modelled the Gaia18ajz event and found its two possible models, the most probable Einstein timescales for which are 316(30 )(+36)days and 299(22)(+25) days. Applying Galaxy priors for stellar density and motion, we calculated a most probable lens mass of 4.9(-2.3)(+5.4) M (R) located at 1.14(+0.75) (-0.57) kpc, and a less probably mass of 11.1(+10.3) (-4.7) M (R) located at 1.31(-0.60)(+0.80) kpc. Our analysis of the blended light suggests that the lens is likely a dark remnant of stellar evolution rather than a main sequence star.

Název v anglickém jazyce

Uncovering the invisible: A study of Gaia18ajz, a candidate black hole revealed by microlensing

Popis výsledku anglicky

Context. Identifying black holes is essential for our understanding of the development of stars and can reveal novel principles of physics. Gravitational microlensing provides an exceptional opportunity to examine an undetectable population of black holes in the Milky Way. In particular, long-lasting events are likely to be associated with massive lenses, including black holes. Aims. We present an analysis of the Gaia18ajz microlensing event reported by the Gaia Science Alerts system. Gaia18ajz is a long-timescale event exhibiting features indicative of the annual microlensing parallax effect. Our objective is to estimate its lens parameters based on the best-fitting model. Methods. We used photometric data obtained from the Gaia satellite and terrestrial observatories to investigate a variety of microlensing models and calculate the most probable mass and distance to the lens, taking into consideration a Galactic model as a prior. Subsequently, we applied a mass-brightness relation to evaluate the likelihood that the lens is a main sequence star. We also describe the DarkLensCode (DLC), an open- source routine that computes the distribution of probable lens mass, distance, and luminosity employing the Galaxy priors on stellar density and velocity for microlensing events with detected microlensing parallax. Results. We modelled the Gaia18ajz event and found its two possible models, the most probable Einstein timescales for which are 316(30 )(+36)days and 299(22)(+25) days. Applying Galaxy priors for stellar density and motion, we calculated a most probable lens mass of 4.9(-2.3)(+5.4) M (R) located at 1.14(+0.75) (-0.57) kpc, and a less probably mass of 11.1(+10.3) (-4.7) M (R) located at 1.31(-0.60)(+0.80) kpc. Our analysis of the blended light suggests that the lens is likely a dark remnant of stellar evolution rather than a main sequence star.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2025

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Astronomy & Astrophysics

ISSN

0004-6361

e-ISSN

1432-0746

Svazek periodika

694

Číslo periodika v rámci svazku

Feb.

Stát vydavatele periodika

FR - Francouzská republika

Počet stran výsledku

19

Strana od-do

A94

Kód UT WoS článku

001414735800002

EID výsledku v databázi Scopus

2-s2.0-85217995284