Imperial College London
Portrait Picture

Mr Chris Carr

Faculty of Natural Sciences, Department of Physics

Senior Research Lecturer
 
 
 
//

Contact

 

+44 (0)20 7594 7765c.m.carr

 
 
//

Assistant

 

Mr Luke Kratzmann +44 (0)20 7594 7770

 
//

Location

 

6M72Huxley BuildingSouth Kensington Campus

//

Summary

 

Publications

Citation

BibTex format

@article{Goetz:2016:0004-6361/201527728,
author = {Goetz, C and Koenders, C and Richter, I and Altwegg, K and Burch, J and Carr, C and Cupido, E and Eriksson, A and Güttler, C and Henri, P and Mokashi, P and Nemeth, Z and Nilsson, H and Rubin, M and Sierks, H and Tsurutani, B and Vallat, C and Volwerk, M and Glassmeier, KH},
doi = {0004-6361/201527728},
journal = {Astronomy & Astrophysics},
title = {First detection of a diamagnetic cavity at comet 67P/Churyumov-Gerasimenko},
url = {http://dx.doi.org/10.1051/0004-6361/201527728},
volume = {588},
year = {2016}
}
Download

RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Context. The Rosetta magnetometer RPC-MAG has been exploring the plasma environment of comet 67P/Churyumov-Gerasimenko since August 2014. The first months were dominated by low-frequency waves which evolved into more complex features. However, at the end of July 2015, close to perihelion, the magnetometer detected a region that did not contain any magnetic field at all. Aims. These signatures match the appearance of a diamagnetic cavity as was observed at comet 1P/Halley in 1986. The cavity here is more extended than previously predicted by models and features unusual magnetic field configurations, which need to be explained. Methods. The onboard magnetometer data were analyzed in detail and used to estimate the outgassing rate. A minimum variance analysis was used to determine boundary normals. Results. Our analysis of the data acquired by the Rosetta Plasma Consortium instrumentation confirms the existence of a diamagnetic cavity. The size is larger than predicted by simulations, however. One possible explanation are instabilities that are propagating along the cavity boundary and possibly a low magnetic pressure in the solar wind. This conclusion is supported by a change in sign of the Sun-pointing component of the magnetic field. Evidence also indicates that the cavity boundary is moving with variable velocities ranging from 230-500 m/s.
AU  - Goetz,C
AU  - Koenders,C
AU  - Richter,I
AU  - Altwegg,K
AU  - Burch,J
AU  - Carr,C
AU  - Cupido,E
AU  - Eriksson,A
AU  - Güttler,C
AU  - Henri,P
AU  - Mokashi,P
AU  - Nemeth,Z
AU  - Nilsson,H
AU  - Rubin,M
AU  - Sierks,H
AU  - Tsurutani,B
AU  - Vallat,C
AU  - Volwerk,M
AU  - Glassmeier,KH
DO  - 0004-6361/201527728
PY  - 2016///
SN  - 1432-0746
TI  - First detection of a diamagnetic cavity at comet 67P/Churyumov-Gerasimenko
T2  - Astronomy & Astrophysics
UR  - http://dx.doi.org/10.1051/0004-6361/201527728
UR  - http://hdl.handle.net/10044/1/31059
VL  - 588
ER  -
Download