2025ApJ...985L..20X

Query : 2025ApJ...985L..20X

2025ApJ...985L..20X - Astrophys. J., 985, L20 (2025/May-3)

XRISM Forecast for the Coma Cluster: Stormy, with a Steep Power Spectrum.

XRISM COLLABORATION, AUDARD M., AWAKI H., BALLHAUSEN R., BAMBA A., BEHAR E., BOISSAY-MALAQUIN R., BRENNEMAN L., BROWN G.V., CORRALES L., COSTANTINI E., CUMBEE R., DIAZ TRIGO M., DONE C., DOTANI T., EBISAWA K., ECKART M.E., ECKERT D., EGUCHI S., ENOTO T., EZOE Y., FOSTER A., FUJIMOTO R., FUJITA Y., FUKAZAWA Y., FUKUSHIMA K., FURUZAWA A., GALLO L., GARCIA J.A., GU L., GUAINAZZI M., HAGINO K., HAMAGUCHI K., HATSUKADE I., HAYASHI K., HAYASHI T., HELL N., HODGES-KLUCK E., HORNSCHEMEIER A., ICHINOHE Y., ISHI D., ISHIDA M., ISHIKAWA K., ISHISAKI Y., KAASTRA J., KALLMAN T., KARA E., KATSUDA S., KANEMARU Y., KELLEY R., KILBOURNE C., KITAMOTO S., KOBAYASHI S., KOHMURA T., KUBOTA A., LEUTENEGGER M., LOEWENSTEIN M., MAEDA Y., MARKEVITCH M., MATSUMOTO H., MATSUSHITA K., McCAMMON D., McNAMARA B., MERNIER F., MILLER E.D., MILLER J.M., MITSUISHI I., MIZUMOTO M., MIZUNO T., MORI K., MUKAI K., MURAKAMI H., MUSHOTZKY R., NAKAJIMA H., NAKAZAWA K., NESS J.-U., NOBUKAWA K., NOBUKAWA M., NODA H., ODAKA H., OGAWA S., OGORZALEK A., OKAJIMA T., OTA N., PALTANI S., PETRE R., PLUCINSKY P., PORTER F.S., POTTSCHMIDT K., SATO K., SATO T., SAWADA M., SETA H., SHIDATSU M., SIMIONESCU A., SMITH R., SUZUKI H., SZYMKOWIAK A., TAKAHASHI H., TAKEO M., TAMAGAWA T., TAMURA K., TANAKA T., TANIMOTO A., TASHIRO M., TERADA Y., TERASHIMA Y., TSUBOI Y., TSUJIMOTO M., TSUNEMI H., TSURU T., TUMER A., UCHIDA H., UCHIDA N., UCHIDA Y., UCHIYAMA H., UEDA S., UEDA Y., UNO S., VINK J., WATANABE S., WILLIAMS B.J., YAMADA S., YAMADA S., YAMAGUCHI H., YAMAOKA K., YAMASAKI N., YAMAUCHI M., YAMAUCHI S., YAQOOB T., YONEYAMA T., YOSHIDA T., YUKITA M., ZHURAVLEVA I., FABIAN A., NELSON D., OKABE N., PILLEPICH A., POTTER C., REGAMEY M., SAKAI K., SHISHIDO M., TRUONG N., WIK D.R. and ZUHONE J.

Abstract (from CDS):

The XRISM Resolve microcalorimeter array measured the velocities of hot intracluster gas at two positions in the Coma galaxy cluster: ${3}^{{\prime} }\times {3}^{{\prime} }$ squares at the center and at 6$^{\prime} $ (170 kpc) to the south. We find the line-of-sight velocity dispersions in those regions to be σz = 208 ± 12 km s–1 and 202 ± 24 km s–1, respectively. The central value corresponds to a 3D Mach number of M = 0.24 ± 0.015 and a ratio of the kinetic pressure of small-scale motions to thermal pressure in the intracluster plasma of only 3.1% ± 0.4%, at the lower end of predictions from cosmological simulations for merging clusters like Coma, and similar to that observed in the cool core of the relaxed cluster A2029. Meanwhile, the gas in both regions exhibits high line-of-sight velocity differences from the mean velocity of the cluster galaxies, Δvz = 450 ± 15 km s–1 and 730 ± 30 km s–1, respectively. A small contribution from an additional gas velocity component, consistent with the cluster optical mean, is detected along a sight line near the cluster center. The combination of the observed velocity dispersions and bulk velocities is not described by a Kolmogorov velocity power spectrum of steady-state turbulence; instead, the data imply a much steeper effective slope (i.e., relatively more power at larger linear scales). This may indicate either a very large dissipation scale, resulting in the suppression of small-scale motions, or a transient dynamic state of the cluster, where large-scale gas flows generated by an ongoing merger have not yet cascaded down to small scales.

Abstract Copyright: © 2025. The Author(s). Published by the American Astronomical Society.

Journal keyword(s): Galaxy clusters - Coma Cluster - Intracluster medium - High resolution spectroscopy

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 - 2026 		#notes
1 ACO 426 ClG 03 19 47.6 +41 30 54           ~ 2508 1
2 ACO 3526 ClG 12 48 49.2 -41 18 17           ~ 1154 2
3 NGC 4839 BiC 12 57 24.3563164776 +27 29 52.203087132 13.56 13.02 12.06     ~ 482 3
4 NGC 4874 LIN 12 59 35.7093764280 +27 57 33.293892204 13.01 13.7 12.71 12.27 11.386 ~ 814 3
5 ACO 1656 ClG 12 59 44.40 +27 54 44.9           ~ 5141 2
6 NGC 4889 EmG 13 00 08.097 +27 58 37.29 12.93 13.0 11.30 11.652 10.906 ~ 742 1
7 ACO 2029 ClG 15 10 54.2 +05 44 23           ~ 1020 0

To bookmark this query, right click on this link: simbad:objects in 2025ApJ...985L..20X and select 'bookmark this link' or equivalent in the popup menu