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Chandra X-ray Observations of Jovian Low-latitude Emissions: Morphological, Temporal, and Spectral CharacteristicsChandra observed X-rays from Jupiter during 24-26 February 2003 for about 40 hours with the ACIS-S and HRC-I instruments. The analysis of Jovian low-latitude "disk" Xray emissions are presented and compared with the high-latitude "auroral" emissions. We report the first Chandra ACIS-S measured X-ray spectrum (0.3-2 keV) of Jupiter's low-latitude disk The disk X-ray emission is harder and extends to higher energies than the auroral spectrum. The temporal variation in the Jovian disk X-rays is on an average consistent with those in the solar X-rays observed by GOES, and TIMED/SSE. Contrary to the auroral X-rays, the disk emissions are uniformly distributed over Jupiter; no indication of longitudinal dependence or correlation with surface magneh field strength is visible. Also, unlike the approx. 40 +/- 20 min periodic oscillations seen in the auroral X-ray emissions, the disk emissions do not show any periodic oscillations. The disk spectrum seems to be consistent with resonant and fluorescent scattering of solar X-rays by the Jovian upper atmosphere. Jupiter's disk is found to be about 50% dimmer in soft X-rays in February 2003 compared that in December 2000, which is consistent with the decrease in solar activity. No evidence of lightning-induced X-rays is seen in the Chandra X-ray data. The Jovian disk spectra observed with Chandra-ACIS is stronger than that observed with XMM-Newton two months later during April 28-29, 2003. The XMM-Newton Xray image of Jupiter shows evidence of limb darkening on the anti-sunward side as seen from Earth, as well as an asymmetry with respect to the subsolar point: suggesting a solar driven process.
Document ID
20050041809
Document Type
Conference Paper
Authors
Bhardwaj, Anil (NASA Marshall Space Flight Center Huntsville, AL, United States)
Elsner, Ronald F. (NASA Marshall Space Flight Center Huntsville, AL, United States)
Gladstone, G. Randall (Southwest Research Inst. San Antonio, TX, United States)
Cravens, Thomas E. (Kansas Univ. Lawrence, KS, United States)
Waiate J. Hunter, Jr. (Michigan Univ. Ann Arbor, MI, United States)
Branduardi-Raymont, Graziella (University Coll. London, United Kingdom)
Ford, Peter (Massachusetts Inst. of Tech. Cambridge, MA, United States)
Date Acquired
August 22, 2013
Publication Date
January 1, 2004
Subject Category
Lunar and Planetary Science and Exploration
Meeting Information
36th Annual Meeting of the American Astronomical Society''s Division for Planetary Sciences(Louisville, KY)
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.