Imperial College London
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DrHeliHietala

Faculty of Natural Sciences, Department of Physics

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Contact

 

+44 (0)20 7594 7660h.hietala CV

 
 
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Location

 

6M58Blackett LaboratorySouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Turner:2021:2041-8213/abec78,
author = {Turner, DL and Wilson, LB and Goodrich, KA and Madanian, H and Schwartz, SJ and Liu, TZ and Johlander, A and Caprioli, D and Cohen, IJ and Gershman, D and Hietala, H and Westlake, JH and Lavraud, B and Le, Contel O and Burch, JL},
doi = {2041-8213/abec78},
journal = {The Astrophysical Journal Letters},
pages = {1--11},
title = {Direct multipoint observations capturing the reformation of a supercritical fast magnetosonic shock},
url = {http://dx.doi.org/10.3847/2041-8213/abec78},
volume = {911},
year = {2021}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Using multipoint Magnetospheric Multiscale (MMS) observations in an unusual string-of-pearls configuration, we examine in detail observations of the reformation of a fast magnetosonic shock observed on the upstream edge of a foreshock transient structure upstream of Earth's bow shock. The four MMS spacecraft were separated by several hundred kilometers, comparable to suprathermal ion gyroradius scales or several ion inertial lengths. At least half of the shock reformation cycle was observed, with a new shock ramp rising up out of the "foot" region of the original shock ramp. Using the multipoint observations, we convert the observed time-series data into distance along the shock normal in the shock's rest frame. That conversion allows for a unique study of the relative spatial scales of the shock's various features, including the shock's growth rate, and how they evolve during the reformation cycle. Analysis indicates that the growth rate increases during reformation, electron-scale physics play an important role in the shock reformation, and energy conversion processes also undergo the same cyclical periodicity as reformation. Strong, thin electron-kinetic-scale current sheets and large-amplitude electrostatic and electromagnetic waves are reported. Results highlight the critical cross-scale coupling between electron-kinetic- and ion-kinetic-scale processes and details of the nature of nonstationarity, shock-front reformation at collisionless, fast magnetosonic shocks.
AU  - Turner,DL
AU  - Wilson,LB
AU  - Goodrich,KA
AU  - Madanian,H
AU  - Schwartz,SJ
AU  - Liu,TZ
AU  - Johlander,A
AU  - Caprioli,D
AU  - Cohen,IJ
AU  - Gershman,D
AU  - Hietala,H
AU  - Westlake,JH
AU  - Lavraud,B
AU  - Le,Contel O
AU  - Burch,JL
DO  - 2041-8213/abec78
EP  - 11
PY  - 2021///
SN  - 2041-8205
SP  - 1
TI  - Direct multipoint observations capturing the reformation of a supercritical fast magnetosonic shock
T2  - The Astrophysical Journal Letters
UR  - http://dx.doi.org/10.3847/2041-8213/abec78
UR  - https://iopscience.iop.org/article/10.3847/2041-8213/abec78
UR  - http://hdl.handle.net/10044/1/88334
VL  - 911
ER  -
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