[Previous] | [Session 24] | [Next]
D. Dewey (MIT CSR)
SNR E0102 is made up of an outer, spherical blastwave region delimited by the forward shock progress into the CSM and an inner "ring" of reverse-shocked ejecta. In addition, there are a variety of spoke-like structures visible in the center of the ring. Velocity effects seen in the optical and X-ray (Flanagan et al. 2004) add a third dimension, suggesting a roughly cylindrical ejecta geometry. This allows the construction of a coarse 3D model for the emitting plasma: a set of 3D-arrays each specifing the emission measure (model "norm") for the emission from one of the X-ray-visible ions, plus an outer blast wave region given by a "vnei" spectrum (Hughes et al. 2000.)
The geometry (3D array values) and global velocity field are iteratively adjusted to roughly agree with the HETG data which includes the dispersed spectral images, the 2D-projected image on the sky, and the zeroth-order global spectrum. The resulting arrays give each ions' emission measure in discrete 3D regions in space. These are then converted self-consistently (i.e., ne is in agreement with nions) into local and global properties which are presented: ne(x,y,z), nion(x,y,z), the mass of each element, etc. The effects of explicit assumptions, e.g., the amount of non-observed ion states like O VI and Ne VIII, are discussed.
Although applied here to the case of a supernova remnant observed with the Chandra HETG, this work is exploratory for a general purpose development effort, "Hydra", which will combine i) explicit 3D source models, ii) ray/photon generation from them, iii) simulating observations for multiple missions, iv) the filtering and comparison of multi-dimensional data sets, and v) the iterative fitting of the model parameters.
This work was carried out in the supportive and stimulating X-ray Group at M.I.T. and was supported by NASA through contract NAS8-01129.
If you would like more information about this abstract, please follow the link to http://space.mit.edu/HETG. This link was provided by the author. When you follow it, you will leave the Web site for this meeting; to return, you should use the Back comand on your browser.
The author(s) of this abstract have provided an email address for comments about the abstract: dd@space.mit.edu
[Previous] | [Session 24] | [Next]
Bulletin of the American Astronomical Society, 36 #3
© 2004. The American Astronomical Soceity.