Change search
ReferencesLink to record
Permanent link

Direct link
Energetic neutral atom imaging of comets
Institutet för rymdfysik (IRF).
2008 (English)In: Geophysical Research Letters, ISSN 0094-8276, Vol. 35, no L05103Article in journal (Refereed) Published
Abstract [en]

We present the first computer simulated images of energetic neutral atoms (ENAs) produced by charge exchange between solar wind protons and cometary neutrals. Proton bulk flow and temperature from MHD simulations are used along with a model of cometary neutral densities. The emission of hydrogen ENAs from the comet is then calculated using cross sections for the charge exchange collisions. The ENA production rate is integrated along lines of sight to produce an image of the fluxes. We find detection of hydrogen ENAs feasible and most favorable at solar zenith angles between 80 and 130 degrees.

Place, publisher, year, edition, pages
2008. Vol. 35, no L05103
URN: urn:nbn:se:umu:diva-3362DOI: 10.1029/2007GL032955OAI: diva2:142029
Available from: 2008-09-04 Created: 2008-09-04Bibliographically approved
In thesis
1. Numerical modelling of ENAs from stellar wind interactions
Open this publication in new window or tab >>Numerical modelling of ENAs from stellar wind interactions
2008 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Energetic neutral atoms (ENAs) are produced whenever a stellar wind encounters a neutral atmosphere. If a stellar wind proton comes sufficiently close to a neutral a charge-exchange reaction may take place, transforming the proton into an ENA. Unaffected by magnetic and electric fields, ENAs provide an opportunity for global imaging of stellar wind interactions.

This thesis presents methods and results of numerical modelling of stellar wind interactions. In particular it treats in depth production of ENAs at comets, Mars and the extrasolar planet HD 209458b.

Sufficiently accurate numerical models of stellar wind interactions require extensive computations. Parallel computing has therefore been used throughout the work, both for fluid and particle simulations of space plasmas. This thesis describes the use of a general simulation tool, providing parallel computing for space plasma simulations.

The thesis presents estimations of the magnitude and morphology of the ENA production at comets and HD 209458b. It compares the results obtained with observations and analyzes them in the light of ENA production at similar objects. Also, simulated ENA images for Mars were produced and compared to observations.

Place, publisher, year, edition, pages
Kiruna: Institutet för rymdfysik (IRF), 2008. 52 p.
IRF Scientific Report, ISSN 0284-1703 ; 297
Space physics, Space technology, Astrophysics
National Category
Aerospace Engineering
urn:nbn:se:umu:diva-1804 (URN)978-91-977255-5-2 (ISBN)
Public defence
2008-09-26, Aulan, Institutet för rymdfysik, Etian 100, Kiruna, 10:00
Available from: 2008-09-04 Created: 2008-09-03Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text
In the same journal
Geophysical Research Letters

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 26 hits
ReferencesLink to record
Permanent link

Direct link