Imperial College London

Dr Jonathan P. Eastwood

Faculty of Natural SciencesDepartment of Physics

Senior Lecturer



+44 (0)20 7594 8101jonathan.eastwood Website




6M63Blackett LaboratorySouth Kensington Campus






BibTex format

author = {Farrugia, CJ and Lugaz, N and Alm, L and Vasquez, B and Argall, MR and Kucharek, H and Matsui, H and Torbert, RB and Lavraud, B and LeContel, O and Cohen, IJ and Burch, JL and Russell, CT and Strangeway, RJ and Shuster, J and Dorelli, JC and Eastwood, JP and Ergun, RE and Fuselier, SA and Gershman, DJ and Giles, BL and Khotyaintsev, YV and Lindqvist, PA and Marklund, GT and Paulson, KW and Petrinec, SM and Phan, TD and Pollock, CJ},
doi = {10.1002/2017JA024563},
journal = {Journal of Geophysical Research: Space Physics},
pages = {9934--9951},
title = {MMS Observations of Reconnection at Dayside Magnetopause Crossings During Transitions of the Solar Wind to Sub-Alfvénic Flow},
url = {},
volume = {122},
year = {2017}

RIS format (EndNote, RefMan)

AB - We present MMS observations during two dayside magnetopause crossings under hithertounexamined conditions: (i) when the bow shock is weakening and the solar wind transitioning tosub-Alfvénic flow and (ii) when it is reforming. Interplanetary conditions consist of a magnetic cloud with (i)a strongB(∼20 nT) pointing south and (ii) a density profile with episodic decreases to values of∼0.3 cm−3followed by moderate recovery. During the crossings the magnetosheath magnetic field is stronger thanthe magnetosphere field by a factor of∼2.2. As a result, during the outbound crossing through the iondiffusion region, MMS observed an inversion of the relative positions of the X and stagnation (S) lines fromthat typically the case: the S line was closer to the magnetosheath side. The S line appears in the form of aslow expansion fan near which most of the energy dissipation is taking place. While in the magnetospherebetween the crossings, MMS observed strong field and flow perturbations, which we argue to be due tokinetic Alfvén waves. During the reconnection interval, whistler mode waves generated by an electrontemperature anisotropy (Te>Te) were observed. Another aim of the paper is to distinguish bowshock-induced field and flow perturbations from reconnection-related signatures. The high-resolutionMMS data together with 2-D hybrid simulations of bow shock dynamics helped us to distinguish betweenthe two sources. We show examples of bow shock-related effects (such as heating) and reconnectioneffects such as accelerated flows satisfying the Walén relation.
AU - Farrugia,CJ
AU - Lugaz,N
AU - Alm,L
AU - Vasquez,B
AU - Argall,MR
AU - Kucharek,H
AU - Matsui,H
AU - Torbert,RB
AU - Lavraud,B
AU - LeContel,O
AU - Cohen,IJ
AU - Burch,JL
AU - Russell,CT
AU - Strangeway,RJ
AU - Shuster,J
AU - Dorelli,JC
AU - Eastwood,JP
AU - Ergun,RE
AU - Fuselier,SA
AU - Gershman,DJ
AU - Giles,BL
AU - Khotyaintsev,YV
AU - Lindqvist,PA
AU - Marklund,GT
AU - Paulson,KW
AU - Petrinec,SM
AU - Phan,TD
AU - Pollock,CJ
DO - 10.1002/2017JA024563
EP - 9951
PY - 2017///
SN - 2169-9380
SP - 9934
TI - MMS Observations of Reconnection at Dayside Magnetopause Crossings During Transitions of the Solar Wind to Sub-Alfvénic Flow
T2 - Journal of Geophysical Research: Space Physics
UR -
UR -
VL - 122
ER -