Constraints on the Density and Elemental Abundances in the Local InterstellarCloud From Photoionization Models

Details Constraints on the Density and Elemental Abundances in the Local InterstellarCloud From Photoionization Models Constraints on the Density and Elemental Abundances in the Local InterstellarCloud From Photoionization Models

May 2007

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2007aas...210.1903s&link_type=abstract

American Astronomical Society Meeting 210, #19.03; Bulletin of the American Astronomical Society, Vol. 39, p.119

Physics

Scientific paper

The Local Interstellar Cloud (LIC) is the warm (T 6300 K), low density (n(H) 0.25 cm-3), partially ionized (X(H) 0.2) region of the interstellar medium (ISM) that immediately surrounds the Solar System. The motion of the Sun through the LIC (v = 26 km/s) and the interaction of the solar wind with the ISM results in the bow shaped heliosphere, which excludes ions and electrons from the Solar System but allows in neutral particles (except those neutrals that charge exchange in the heliopause) that are then observable in several different ways. The ionization of the LIC is a critical factor in determining the nature of the heliosphere since the interstellar ions exert ram pressure and the neutrals, which get ionized inside the heliosphere, mass-load the solar wind. We present results from modeling the thermal balance and photoionization of the LIC by the interstellar radiation field made up of stellar FUV and EUV, diffuse soft X-ray emission from the hot gas of the Local Bubble and EUV/soft X-ray emission from the thermally conductive boundary between the LIC and the Local Bubble. We find that we can satisfy the observational constraints, including the temperature and density of He0 at the Sun, for a range of model parameters that affect the radiation field. Despite the variation in the radiation field, the resulting constraints on the HI and electron density at the Sun are quite tight, n(HI) = 0.19 — 0.20 cm-3 and n(e) = 0.05 — 0.08 cm-3. We find that abundances required in the LIC indicate significant depletion of elements contained in silicate dust while C has supersolar abundance.
This research was supported by NASA Solar and Heliospheric Physics Program grants NNG05GD36G and NNG06GE33G, and by NNG05EC85C to SWRI.

Affiliated with

Also associated with

No associations

Rating

Constraints on the Density and Elemental Abundances in the Local InterstellarCloud From Photoionization Models does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Constraints on the Density and Elemental Abundances in the Local InterstellarCloud From Photoionization Models, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Constraints on the Density and Elemental Abundances in the Local InterstellarCloud From Photoionization Models will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1028915