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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Turbulence-induced magnetic fields in shock precursors

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Author(s):
del Valle, M. V. [1] ; Lazarian, A. [2] ; Santos-Lima, R. [3]
Total Authors: 3
Affiliation:
[1] Inst Argentino Radioastron, CC-5, RA-1894 Buenos Aires, DF - Argentina
[2] Univ Wisconsin, Dept Astron, 475 N Charter St, Madison, WI 53706 - USA
[3] Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, BR-05508090 Sao Paulo, SP - Brazil
Total Affiliations: 3
Document type: Journal article
Source: Monthly Notices of the Royal Astronomical Society; v. 458, n. 2, p. 1645-1659, MAY 11 2016.
Web of Science Citations: 8
Abstract

Galactic cosmic rays are believed to be mostly accelerated at supernova shocks. However, the interstellar magnetic field is too weak to efficiently accelerate galactic cosmic rays up to the highest energies, i.e. 10(15) eV. A stronger magnetic field in the pre-shock region could provide the efficiency required. Bell's cosmic ray non-resonant streaming instability has been claimed to be responsible for the amplification of precursor magnetic fields. However, an alternative mechanism has been proposed in which the cosmic ray pressure gradient forms the shock precursor and drives turbulence, amplifying the magnetic field via the small-scale dynamo. Key ingredients for the mechanism to operate are the inhomogeneities present in the interstellar medium. These inhomogeneities are the consequence of turbulence. In this work we explore the magnetic field amplification in different interstellar medium conditions through 3D magnetohydrodynamic numerical simulations. (AU)

FAPESP's process: 09/54006-4 - A computer cluster for the Astronomy Department of the University of São Paulo Institute of Astronomy, Geophysics and Atmospheric Sciences and for the Cruzeiro do Sul University Astrophysics Center
Grantee:Elisabete Maria de Gouveia Dal Pino
Support Opportunities: Multi-user Equipment Program
FAPESP's process: 13/15115-8 - Study of collisionless plasma effects: application to the turbulent intracluster medium of galaxies
Grantee:Reinaldo Santos de Lima
Support Opportunities: Scholarships in Brazil - Post-Doctoral