Theoretical and Natural Science
- The Open Access Proceedings Series for Conferences
Theoretical and Natural Science
Vol. 10, 17 November 2023
Open
Access | Article
Compact object probed by microlensing in the universe: MACHOs, stars, planets?
* Author to whom correspondence should be addressed.
Abstract
Nearly 30% of the components in the universe are dark matter, hitherto, astronomers are still uncertain about their properties. This project attempts to constrain whether dark matter is MACHOs or diffused particles via statistics of microlensing events observed toward quasars, which are the brightest objects in the Universe. The identification of isolated microlensing events enables us to study stellar and planetary objects in distant universes that would be otherwise unobservable. During the research two isolated microlensing events toward quasar J1821 is discovered in the first 25 quasars in our sample. The WISE light curves in W1 and W2 bands are almost identical in magnification, consistent with achromatic variability due to microlensing. The crossing times for the two events are about 2 days and 1.3 days, thus the lenses are probably a star or sub-stellar object. By assuming the lenses are in galaxies of the galactic cluster with a redshift of 0.81 lying in our sight of view to the quasar, calculations of the mass of the lenses as a function of its velocity can be made, yielding a planetary mass or less in the relative velocity dominated by the movements of galaxies. If the superluminous motion of jets in a quasar dominates the relative velocity, stellar masses are derived. The data analysis yielded from the microlensing light curves of J1821 suggests microlensing as a method for astronomers to further study stellar and sub-stellar objects in our Universe.
Keywords
dark matter, microlensing events, redshift, mass of the lenses
References
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5. Gioia, I.M., Wolter, A., Mullis, C.R., Henry, J.P., Böhringer, H. and Briel, U.G., 2004. RX J1821. 6+ 6827: A cool cluster at z= 0.81 from the ROSAT NEP survey. Astronomy & Astrophysics, 428(3), pp.867-875.
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Data Availability
The datasets used and/or analyzed during the current study will be available from the authors upon reasonable request.
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- Volume Title
- Proceedings of the 2023 International Conference on Mathematical Physics and Computational Simulation
- ISBN (Print)
- 978-1-83558-131-5
- ISBN (Online)
- 978-1-83558-132-2
- Published Date
- 17 November 2023
- Series
- Theoretical and Natural Science
- ISSN (Print)
- 2753-8818
- ISSN (Online)
- 2753-8826
- DOI
- 10.54254/2753-8818/10/20230310
- Copyright
- 17 November 2023
- Open Access
- This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited