Extinction and Scattering Properties of Dust Around Red Supergiants

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

We have been amassing a unique dataset which can be used to investigate the amount and nature of dust produced by red supergiants (RSGs) in very different environments. To this end, optical spectra are being obtained for RSGs in various galaxies in the Local Group. Moderate-resolution, high S/N, spectrophotometry, covering 3500-9000A, has been obtained for a sample of RSGs in the Milky Way and the Magellanic Clouds. Using the the MARCS stellar atmosphere models to fit the SEDs, we are deriving extinction curves from 3500A to the K-band for the Local Group RSGs. In particular, for the LMC and SMC stars, the problem is more tractable than for the Milky Way RSGs, given the small and relatively uniform foreground extinction of the Clouds. We will construct extinction curves using the classic "pair method". The feasibility of using the model SEDs as "unreddened" standards will be examined, as well as the more conventional pairing of stars that are closely matched in spectral type but have different reddenings. These extinction curves are actually attenuation curves since the RSG circumstellar dust shells are not resolved and light can be scattered back into the beam. In particular, we plan to examine the apparent NUV excess seen in the Galactic RSG extinction curves. The NUV excess is possibly due to scattering of the star's light by circumstellar dust and/or a larger average size than that typical of grains found in the diffuse interstellar medium.
This project is being supported by NSF grant AST-0707691 and a LaSPACE Undergraduate Research Assistantship (NASA grant NNG05GH22H).

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Extinction and Scattering Properties of Dust Around Red Supergiants 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 Extinction and Scattering Properties of Dust Around Red Supergiants, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Extinction and Scattering Properties of Dust Around Red Supergiants will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1479723

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.