Imperial College London
Alternate

ProfessorMicheleDougherty

Faculty of Natural Sciences, Department of Physics

Head of Department of Physics, Professor of Space Physics
 
 
 
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Contact

 

+44 (0)20 7594 7770m.dougherty Website

 
 
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Assistant

 

Ms Lida Mnatsakanian +44 (0)20 7594 7503

 
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Location

 

Blackett 900aBlackett LaboratorySouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Sulaiman:2015:10.1103/PhysRevLett.115.125001,
author = {Sulaiman, AH and Masters, A and Dougherty, MK and Burgess, D and Fujimoto, M and Hospodarsky, GB},
doi = {10.1103/PhysRevLett.115.125001},
journal = {Physical Review Letters},
title = {Quasiperpendicular high Mach number shocks},
url = {http://dx.doi.org/10.1103/PhysRevLett.115.125001},
volume = {115},
year = {2015}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Shock waves exist throughout the Universe and are fundamental to understanding the nature of collisionless plasmas. Reformation is a process, driven by microphysics, which typically occurs at high Mach number supercritical shocks. While ongoing studies have investigated this process extensively both theoretically and via simulations, their observations remain few and far between. In this Letter we present a study of very high Mach number shocks in a parameter space that has been poorly explored and we identify reformation using in situ magnetic field observations from the Cassini spacecraft at 10 AU. This has given us an insight into quasiperpendicular shocks across 2 orders of magnitude in Alfvén Mach number (MA) which could potentially bridge the gap between modest terrestrial shocks and more exotic astrophysical shocks. For the first time, we show evidence for cyclic reformation controlled by specular ion reflection occurring at the predicted time scale of ∼0.3τc, where τc is the ion gyroperiod. In addition, we experimentally reveal the relationship between reformation and MA and focus on the magnetic structure of such shocks to further show that for the same MA, a reforming shock exhibits stronger magnetic field amplification than a shock that is not reforming.
AU  - Sulaiman,AH
AU  - Masters,A
AU  - Dougherty,MK
AU  - Burgess,D
AU  - Fujimoto,M
AU  - Hospodarsky,GB
DO  - 10.1103/PhysRevLett.115.125001
PY  - 2015///
SN  - 1079-7114
TI  - Quasiperpendicular high Mach number shocks
T2  - Physical Review Letters
UR  - http://dx.doi.org/10.1103/PhysRevLett.115.125001
UR  - http://hdl.handle.net/10044/1/26260
VL  - 115
ER  -
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