THE ABUNDANCE OF BULLET GROUPS IN ΛCDM
Abstract
We estimate the expected distribution of displacements between the two dominant dark matter (DM) peaks (DM-DM displacements) and between the DM and gaseous baryon peak (DM-gas displacements) in DM halos with masses larger than 10{sup 13} h {sup –1} M {sub ☉}. As a benchmark, we use the observation of SL2S J08544–0121, which is the lowest mass system (1.0 × 10{sup 14} h {sup –1} M {sub ☉}) observed so far, featuring a bi-modal DM distribution with a dislocated gas component. We find that (50 ± 10)% of the DM halos with circular velocities in the range 300-700 km s{sup –1} (groups) show DM-DM displacements equal to or larger than 186 ± 30 h {sup –1} kpc as observed in SL2S J08544–0121. For DM halos with circular velocities larger than 700 km s{sup –1} (clusters) this fraction rises to (70 ± 10)%. Using the same simulation, we estimate the DM-gas displacements and find that 0.1%-1.0% of the groups should present separations equal to or larger than 87 ± 14 h {sup –1} kpc, corresponding to our observational benchmark; for clusters, this fraction rises to (7 ± 3)%, consistent with previous studies of DM to baryon separations. Considering both constraints on the DM-DM and DM-gasmore »
- Authors:
-
- Departamento de Física, Universidad de los Andes, Cra. 1 No. 18A-10, Edificio Ip, Bogotá (Colombia)
- Instituto de Física y Astronomía, Universidad de Valparaíso, Avda. Gran Bretaña 1111, Playa Ancha, Valparaíso 2360102 (Chile)
- Publication Date:
- OSTI Identifier:
- 22365816
- Resource Type:
- Journal Article
- Journal Name:
- Astrophysical Journal Letters
- Additional Journal Information:
- Journal Volume: 787; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 2041-8205
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BARYONS; BENCHMARKS; COMPUTERIZED SIMULATION; COSMOLOGICAL CONSTANT; COSMOLOGY; GALAXIES; GALAXY CLUSTERS; LIMITING VALUES; MASS; MAXIMUM PERMISSIBLE CONCENTRATION; NONLUMINOUS MATTER; STAR CLUSTERS
Citation Formats
Fernández-Trincado, J. G., Forero-Romero, J. E., Foex, G., Motta, V., and Verdugo, T., E-mail: jfernandez@obs-besancon.fr, E-mail: je.forero@uniandes.edu.co. THE ABUNDANCE OF BULLET GROUPS IN ΛCDM. United States: N. p., 2014.
Web. doi:10.1088/2041-8205/787/2/L34.
Fernández-Trincado, J. G., Forero-Romero, J. E., Foex, G., Motta, V., & Verdugo, T., E-mail: jfernandez@obs-besancon.fr, E-mail: je.forero@uniandes.edu.co. THE ABUNDANCE OF BULLET GROUPS IN ΛCDM. United States. https://doi.org/10.1088/2041-8205/787/2/L34
Fernández-Trincado, J. G., Forero-Romero, J. E., Foex, G., Motta, V., and Verdugo, T., E-mail: jfernandez@obs-besancon.fr, E-mail: je.forero@uniandes.edu.co. 2014.
"THE ABUNDANCE OF BULLET GROUPS IN ΛCDM". United States. https://doi.org/10.1088/2041-8205/787/2/L34.
@article{osti_22365816,
title = {THE ABUNDANCE OF BULLET GROUPS IN ΛCDM},
author = {Fernández-Trincado, J. G. and Forero-Romero, J. E. and Foex, G. and Motta, V. and Verdugo, T., E-mail: jfernandez@obs-besancon.fr, E-mail: je.forero@uniandes.edu.co},
abstractNote = {We estimate the expected distribution of displacements between the two dominant dark matter (DM) peaks (DM-DM displacements) and between the DM and gaseous baryon peak (DM-gas displacements) in DM halos with masses larger than 10{sup 13} h {sup –1} M {sub ☉}. As a benchmark, we use the observation of SL2S J08544–0121, which is the lowest mass system (1.0 × 10{sup 14} h {sup –1} M {sub ☉}) observed so far, featuring a bi-modal DM distribution with a dislocated gas component. We find that (50 ± 10)% of the DM halos with circular velocities in the range 300-700 km s{sup –1} (groups) show DM-DM displacements equal to or larger than 186 ± 30 h {sup –1} kpc as observed in SL2S J08544–0121. For DM halos with circular velocities larger than 700 km s{sup –1} (clusters) this fraction rises to (70 ± 10)%. Using the same simulation, we estimate the DM-gas displacements and find that 0.1%-1.0% of the groups should present separations equal to or larger than 87 ± 14 h {sup –1} kpc, corresponding to our observational benchmark; for clusters, this fraction rises to (7 ± 3)%, consistent with previous studies of DM to baryon separations. Considering both constraints on the DM-DM and DM-gas displacements, we find that the number density of groups similar to SL2S J08544–0121 is ∼6.0 × 10{sup –7} Mpc{sup –3}, three times larger than the estimated value for clusters. These results open up the possibility for a new statistical test of ΛCDM by looking for DM-gas displacements in low mass clusters and groups.},
doi = {10.1088/2041-8205/787/2/L34},
url = {https://www.osti.gov/biblio/22365816},
journal = {Astrophysical Journal Letters},
issn = {2041-8205},
number = 2,
volume = 787,
place = {United States},
year = {Sun Jun 01 00:00:00 EDT 2014},
month = {Sun Jun 01 00:00:00 EDT 2014}
}