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 = {Horbury, T and Woolley, T and Laker, R and Matteini, L and Eastwood, J and Bale, SD and Velli, M and Chandran, BDG and Phan, T and Raouafi, NE and Goetz, K and Harvey, PR and Pulupa, M and Klein, KG and De, Wit TD and Kasper, JC and Korreck, KE and Case, AW and Stevens, ML and Whittlesey, P and Larson, D and MacDowall, RJ and Malaspina, DM and Livi, R},
doi = {1538-4365/ab5b15},
journal = {The Astrophysical Journal: an international review of astronomy and astronomical physics},
pages = {1--8},
title = {Sharp Alfvenic impulses in the near-Sun solar wind},
url = {},
volume = {246},
year = {2020}

RIS format (EndNote, RefMan)

AB - Measurements of the near-Sun solar wind by Parker Solar Probe have revealed the presence of largenumbers of discrete Alfv enic impulses with an anti-Sunward sense of propagation. These are similarto those previously observed near 1 AU, in high speed streams over the Sun’s poles and at 60 solarradii. At 35 solar radii, however, they are typically shorter and sharper than seen elsewhere. Inaddition, these spikes occur in “patches” and there are also clear periods within the same stream whenthey do not occur; the timescale of these patches might be related to the rate at which the spacecraftmagnetic footpoint tracks across the coronal hole from which the plasma originated. While the velocityfluctuations associated with these spikes are typically under 100 km/s, due to the rather low Alfv enspeeds in the streams observed by the spacecraft to date, these are still associated with large angulardeflections of the magnetic field - and these deflections are not isotropic. These deflections do notappear to be related to the recently reported large scale, pro-rotation solar wind flow. Estimates ofthe size and shape of the spikes reveal high aspect ratio flow-aligned structures with a transverse scaleof≈104km. These events might be signatures of near-Sun impulsive reconnection events.
AU - Horbury,T
AU - Woolley,T
AU - Laker,R
AU - Matteini,L
AU - Eastwood,J
AU - Bale,SD
AU - Velli,M
AU - Chandran,BDG
AU - Phan,T
AU - Raouafi,NE
AU - Goetz,K
AU - Harvey,PR
AU - Pulupa,M
AU - Klein,KG
AU - De,Wit TD
AU - Kasper,JC
AU - Korreck,KE
AU - Case,AW
AU - Stevens,ML
AU - Whittlesey,P
AU - Larson,D
AU - MacDowall,RJ
AU - Malaspina,DM
AU - Livi,R
DO - 1538-4365/ab5b15
EP - 8
PY - 2020///
SN - 0004-637X
SP - 1
TI - Sharp Alfvenic impulses in the near-Sun solar wind
T2 - The Astrophysical Journal: an international review of astronomy and astronomical physics
UR -
UR -
UR -
VL - 246
ER -