Hostname: page-component-78c5997874-j824f Total loading time: 0 Render date: 2024-11-02T22:21:10.506Z Has data issue: false hasContentIssue false

Thermal and non-thermal connection in radio mini-halos

Published online by Cambridge University Press:  07 April 2020

A. Ignesti
Affiliation:
DIFA, University of Bologna, Via Gobetti 93/2, 40129Bologna, Italy email: [email protected] IRA INAF, Via Gobetti 101, 40129Bologna, Italy
G. Brunetti
Affiliation:
IRA INAF, Via Gobetti 101, 40129Bologna, Italy
M. Gitti
Affiliation:
DIFA, University of Bologna, Via Gobetti 93/2, 40129Bologna, Italy email: [email protected] IRA INAF, Via Gobetti 101, 40129Bologna, Italy
S. Giacintucci
Affiliation:
U.S. NRL, 4555 Overlook Avenue SW, Code 7213, Washington, DC20375, USA
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Several cool-core clusters are known to host a radio mini-halo, a diffuse, steep-spectrum radio source located in their cores, thus probing the presence of non-thermal components as magnetic field and relativistic particles on scales not directly influenced by the central AGN. The nature of the mechanism that produces a population of radio-emitting relativistic particles on the scale of hundreds of kiloparsecs is still unclear. At the same time, it is still debated if the central AGN may play a role in the formation of mini-halos by providing the seed of the relativistic particles. We aim to investigate these open issues by studying the connection between thermal and non-thermal components of the intra-cluster medium. We performed a point-to-point analysis of the radio and the X-ray surface brightness of a compilation of mini-halos. We find that mini-halos have super-linear scalings between radio and X-rays, with radio brightness declining more steeply than the X-ray brightness. This trend is opposite to that generally observed in giant radio halos, thus marking a possible difference in the physics of the two radio sources. Finally, using the scalings between radio and X-rays and assuming a hadronic origin of mini-halos we derive constraints on the magnetic field in the core of the hosting clusters.

Type
Contributed Papers
Copyright
© International Astronomical Union 2020

References

Ahnen, M. L., Ansoldi, S., Antonelli, L. A., et al. 2016, Astronomy and Astrophysics, 589, A33CrossRefGoogle Scholar
Blasi, P. & Colafrancesco, S. 1999, Astroparticle Physics, 12, 169CrossRefGoogle Scholar
Brunetti, G. & Jones, T. W. 2014, International Journal of Modern Physics D, 23, 30007CrossRefGoogle Scholar
Brunetti, G. & Lazarian, A. 2016, Monthly Notices of the RAS, 458, 2584CrossRefGoogle Scholar
Carilli, C. L. & Taylor, G. B. 2002, Annual Review of Astronomy and Astrophysics, 40, 319CrossRefGoogle Scholar
Cavaliere, A. & Fusco-Femiano, R. 1976, Astronomy and Astrophysics, 49, 137Google Scholar
Doria, A., Gitti, M., Ettori, S., et al. 2012, Astrophysical Journal, 753, 47CrossRefGoogle Scholar
Feretti, L., Fusco-Femiano, R., Giovannini, G., & Govoni, F. 2001, Astronomy and Astrophysics, 373, 106CrossRefGoogle Scholar
Giacintucci, S., Markevitch, M., Cassano, R., et al. 2017, Astrophysical Journal, 841, 71CrossRefGoogle Scholar
Gitti, M., Brunetti, G., & Setti, G. 2002, Astronomy and Astrophysics, 386, 456CrossRefGoogle Scholar
Govoni, F., Enßlin, T. A., Feretti, L., & Giovannini, G. 2001, Astronomy and Astrophysics, 369, 441CrossRefGoogle Scholar
Hudson, D. S., Mittal, R., Reiprich, T. H., et al. 2010, Astronomy and Astrophysics, 513, A37CrossRefGoogle Scholar
Pfrommer, C. & Enßlin, T. A. 2004, Astronomy and Astrophysics, 413, 17CrossRefGoogle Scholar
Sun, M. 2009, Astrophysical Journal, 704, 1586CrossRefGoogle Scholar
Tribble, P. C. 1993, Monthly Notices of the RAS, 263, 31CrossRefGoogle Scholar