Determination of the local dark matter density using K-dwarfs from Gaia DR2
Local dark matter density, ρdm, is one of the crucial astrophysical inputs for the estimation of detection rates in dark matter direct search experi- ments. Knowing the value also helps us to investigate the shape of the Galactic dark halo, which is of importance for indirect dark matter searches, a...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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EDP Sciences
2020-01-01
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| Series: | EPJ Web of Conferences |
| Online Access: | https://www.epj-conferences.org/articles/epjconf/pdf/2020/16/epjconf_seaan2020_04002.pdf |
| _version_ | 1818652948439236608 |
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| author | Wardana M. Dafa Wulandari Hesti Sulistiyowati Khatami Akbar H. |
| author_facet | Wardana M. Dafa Wulandari Hesti Sulistiyowati Khatami Akbar H. |
| author_sort | Wardana M. Dafa |
| collection | DOAJ |
| description | Local dark matter density, ρdm, is one of the crucial astrophysical inputs for the estimation of detection rates in dark matter direct search experi- ments. Knowing the value also helps us to investigate the shape of the Galactic dark halo, which is of importance for indirect dark matter searches, as well as for various studies in astrophysics and cosmology. In this work, we performed kinematics study of stars in the solar neighborhood to determine the local dark matter density. As tracers we used 95,543 K-dwarfs from Gaia DR2 inside a heliocentric cylinder with a radius of 150 pc and height 200 pc above and below the Galactic mid plane. Their positions and motions were analyzed, assum- ing that the Galaxy is axisymmetric and the tracers are in dynamical equilib- rium. We applied Jeans and Poisson equations to relate the observed quantities, i.e. vertical position and velocity, with the local dark matter density. The tilt term in the Jeans equation is considered to be small and is therefore neglected. Galactic disk is modelled to consist of a single exponential stellar disk, a thin gas layer, and dark matter whose density is constant within the volume consid- ered. Marginalization for the free parameters was performed with Bayesian theorem using Markov Chain Monte Carlo (MCMC) method. We find that ρdm = 0.0116 ± 0.0012 MO/pc or ρdm = 0.439 ± 0.046 GeV/cm3, in agreement within the range of uncertainty with results of several previous studies. |
| first_indexed | 2024-12-17T02:30:07Z |
| format | Article |
| id | doaj.art-33f1e5d5e3db4d089c5d152620eaded1 |
| institution | Directory Open Access Journal |
| issn | 2100-014X |
| language | English |
| last_indexed | 2024-12-17T02:30:07Z |
| publishDate | 2020-01-01 |
| publisher | EDP Sciences |
| record_format | Article |
| series | EPJ Web of Conferences |
| spelling | doaj.art-33f1e5d5e3db4d089c5d152620eaded12022-12-21T22:06:59ZengEDP SciencesEPJ Web of Conferences2100-014X2020-01-012400400210.1051/epjconf/202024004002epjconf_seaan2020_04002Determination of the local dark matter density using K-dwarfs from Gaia DR2Wardana M. Dafa0Wulandari Hesti1Sulistiyowati2Khatami Akbar H.3Astronomy Study Program, Institut Teknologi BandungAstronomy Research Division, Institut Teknologi BandungSkyLabs, DepokAstronomy Study Program, Institut Teknologi BandungLocal dark matter density, ρdm, is one of the crucial astrophysical inputs for the estimation of detection rates in dark matter direct search experi- ments. Knowing the value also helps us to investigate the shape of the Galactic dark halo, which is of importance for indirect dark matter searches, as well as for various studies in astrophysics and cosmology. In this work, we performed kinematics study of stars in the solar neighborhood to determine the local dark matter density. As tracers we used 95,543 K-dwarfs from Gaia DR2 inside a heliocentric cylinder with a radius of 150 pc and height 200 pc above and below the Galactic mid plane. Their positions and motions were analyzed, assum- ing that the Galaxy is axisymmetric and the tracers are in dynamical equilib- rium. We applied Jeans and Poisson equations to relate the observed quantities, i.e. vertical position and velocity, with the local dark matter density. The tilt term in the Jeans equation is considered to be small and is therefore neglected. Galactic disk is modelled to consist of a single exponential stellar disk, a thin gas layer, and dark matter whose density is constant within the volume consid- ered. Marginalization for the free parameters was performed with Bayesian theorem using Markov Chain Monte Carlo (MCMC) method. We find that ρdm = 0.0116 ± 0.0012 MO/pc or ρdm = 0.439 ± 0.046 GeV/cm3, in agreement within the range of uncertainty with results of several previous studies.https://www.epj-conferences.org/articles/epjconf/pdf/2020/16/epjconf_seaan2020_04002.pdf |
| spellingShingle | Wardana M. Dafa Wulandari Hesti Sulistiyowati Khatami Akbar H. Determination of the local dark matter density using K-dwarfs from Gaia DR2 EPJ Web of Conferences |
| title | Determination of the local dark matter density using K-dwarfs from Gaia DR2 |
| title_full | Determination of the local dark matter density using K-dwarfs from Gaia DR2 |
| title_fullStr | Determination of the local dark matter density using K-dwarfs from Gaia DR2 |
| title_full_unstemmed | Determination of the local dark matter density using K-dwarfs from Gaia DR2 |
| title_short | Determination of the local dark matter density using K-dwarfs from Gaia DR2 |
| title_sort | determination of the local dark matter density using k dwarfs from gaia dr2 |
| url | https://www.epj-conferences.org/articles/epjconf/pdf/2020/16/epjconf_seaan2020_04002.pdf |
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