Current Work - Dan Dewey updated 5/9/2012

My main research areas include Supernovae (SNe) and Supernova remnants (SNRs. See the Chandra-view of SNRs ! ) : their plasma physics and observations of them with the HETG on Chandra. The high resolution of the HETG can provide better identification and measurement of the emission lines in some SNRs, helping to determine the plasma properties. In addition, measurement of Doppler shifts of lines gives velocity information along the line-of-sight, adding a "third dimension" to the structure of the remnant. For more details see the review article "Kinematics of SN/SNRs: Status of X-Ray Observations", http://arxiv.org/abs/1011.4292 .

In the past years I've continued research of core-collapse supernova remnants (SNRs) using high resolution data from the Chandra HETG. Research focussed on three objects: SN 1987A, SN 1996cr and the Cas A SNR.
For SN 1987A, HETG lineshapes indicate two Doppler components, hydrodynamic models of these can be combined to model the observed spectra and light curves. The results were recently published, see Dewey et al (2012), http://arxiv.org/abs/1111.5314 .
After initial global hyrodynamic modeling of SN 1996cr (Dwarkadas, Dewey & Bauer, 2010) detailed fitting was done of the HETG line shapes using simple 3D models of the ejecta-CSM emission geometry as summarized in a GRB meeting proceedings article, http://arxiv.org/abs/1102.1442 .
Following the 3-D Cas A modeling progress of DeLaney et al. (2010, http://arxiv.org/abs/1011.3858), a second epoch HETG observation of Cas A was taken and analyzed. Spatial-spectral models of individual bright features were used to determine their velocities and better resolve closely-spaced emission lines.

Most recently I am working on the 3-epochs of HETG observations of the SNR E0102 . . .


Rendering of SN 1996cr
from HETG line shapes.



SN 1987A based on
"2x1D" hydrodynamics.
(click for movie)

Recent projects:


SN 1987A model components

HETG observations of E0102

Some random items from the past:
BD+30 3639 , Vik-Viz , Ia-Viz , SubApert , MEM .


Related links:
General: Galactic SNR's: LMC/SMC SNR's: