Is there a giant Kelvin-Helmholtz instability in the sloshing cold front of the Perseus cluster?
MetadataShow full item record
This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2017 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.
Deep observations of nearby galaxy clusters with Chandra have revealed concave ‘bay’ structures in a number of systems (Perseus, Centaurus and Abell 1795), which have similar X-ray and radio properties. These bays have all the properties of cold fronts, where the temperature rises and density falls sharply, but are concave rather than convex. By comparing to simulations of gas sloshing, we find that the bay in the Perseus cluster bears a striking resemblance in its size, location and thermal structure, to a giant (≈50 kpc) roll resulting from Kelvin–Helmholtz instabilities. If true, the morphology of this structure can be compared to simulations to put constraints on the initial average ratio of the thermal and magnetic pressure, β = pth/pB, throughout the overall cluster before the sloshing occurs, for which we find β = 200 to best match the observations. Simulations with a stronger magnetic field (β = 100) are disfavoured, as in these the large Kelvin–Helmholtz rolls do not form, while in simulations with a lower magnetic field (β = 500), the level of instabilities is much larger than is observed. We find that the bay structures in Centaurus and Abell 1795 may also be explained by such features of gas sloshing.
Showing items related by title, author, creator and subject.
Gendron-Marsolais, M.; Hlavacek-Larrondo, J.; van Weeren, R.; Clarke, T.; Fabian, A.; Intema, Hubertus; Taylor, G.; Blundell, K.; Sanders, J. (2017)We present a low-frequency view of the Perseus cluster with new observations from the Karl G. Jansky Very Large Array (JVLA) at 230-470 MHz. The data reveal a multitude of new structures associated with the mini-halo. The ...
MEASUREMENTS of the SUNYAEV-ZEL'DOVICH EFFECT in MACS J0647.7+7015 and MACS J1206.2-0847 at HIGH ANGULAR RESOLUTION with MUSTANGYoung, A.; Mroczkowski, T.; Romero, C.; Sayers, J.; Balestra, I.; Clarke, T.; Czakon, N.; Devlin, M.; Dicker, S.; Ferrari, C.; Girardi, M.; Golwala, S.; Intema, Hubertus; Korngut, P.; Mason, B.; Mercurio, A.; Nonino, M.; Reese, E.; Rosati, P.; Sarazin, C.; Umetsu, K. (2015)We present high resolution (9?) imaging of the Sunyaev-Zel'dovich Effect (SZE) toward two massive galaxy clusters, MACS J0647.7+7015 (z = 0.591) and MACS J1206.2-0847 (z = 0.439). We compare these 90 GHz measurements, ...
Savini, F.; Bonafede, A.; Brüggen, M.; Rafferty, D.; Shimwell, T.; Botteon, A.; Brunetti, G.; Intema, Huib; Wilber, A.; Cassano, R.; Vazza, F.; Van Weeren, R.; Cuciti, V.; De Gasperin, F.; Röttgering, H.; Sommer, M.; Bîrzan, L.; Drabent, A. (2019)Centrally located diffuse radio emission has been observed in both merging and non-merging galaxy clusters. Depending on their morphology and size, we distinguish between giant radio haloes, which occur predominantly in ...