Colorado Research Associates of Boulder, Colorado (a division of NorthWest Research Associates, Bellevue, Washington) invites applications for a postdoctoral position in solar physics, specifically spectropolarimetry/vector magnetic field observations. The successful candidate will be responsible for the analysis and interpretation of vector magnetograph data primarily from the Imaging Vector Magnetograph (Mees Solar Obs/U. Hawai`i) and the Advanced Stokes Polarimeter (NSO/HAO) for studies related to solar activity.

A PhD (or Masters' plus at least 3 years additional relevant experience) in astronomy, physics or related discipline is required; experience with spectroscopy, polarimetry and image processing is desired, as is familiarity with UNIX and the IDL programming language. Minimum annual salary is $40,000, plus full benefits. Please send a curriculum vita, list of publications (including preprints or URLs for those manuscripts submitted but not yet published), and the names, addresses and phone numbers for three references to: Dr. K.D. Leka, Colorado Research Associates, 3380 Mitchell Ln., Boulder, CO 80301, by Friday, 17 March 2000. The position has a negotiable starting date of 1 June, and is currently open for one year with likely renewals contingent on performance and funding. CoRA is an Affirmative Action/Equal Opportunity Employer; women and minorities are encouraged to apply. Inquiries should be made to Dr. KD Leka, leka@colorado-research.com, (303) 415-9701 x219.

DETAILS, DETAILS
The project for which the position is advertised uses data from the Imaging Vector Magnetograph. The goal is to detect changes in the photospheric magnetic fields (if any) that may routinely occur prior to solar flares. Details on the IVM can be found in: Mickey, D. L., Canfield, R.C., LaBonte, B. J., Leka, K. D., Waterson, M. F., and Weber, H. M., 1996, "The Imaging Vector Magnetograph at Haleakala", Solar Physics, 168, p229. and in Mickey, D. L., LaBonte, B. J., and Leka, K. D., 1999, "The Imaging Vector Magnetograph at Haleakala II: Reconstruction of Stokes Spectra", Solar Physics (in press) (click here for a preprint of the latter.) This instrument provides quantitative magnetic flux maps at the solar photosphere, and is capable of high time resolution, as can be seen in IVM (white-light quick-look)movies.

Two approaches have been proposed, the first is a quantitative and statistical analysis of the solar parameters measured by vector magnetograms including the changes in the magnetic flux, its curl, velocities, and appropriate gradients of these quantities. A preliminary attempt using this approach has been performed, and looks promising. The second approach is to apply the Minimum Current Corona analysis to the data. This aspect will work closely with Dr. Dana Longcope, of Montana State University. This approach has been used for one small flare and one magnetogram (Longcope, D., Silva, A. V. R., 1998, "A Current Ribbon Model for Energy Storage and Release with Application to the Flare of 7 January 1992", Solar Physics,179, p349.). Our interest is now to apply this coronal modeling approach to a wider set of flaring and non-flaring active regions.

The position will involve: data acquisition from U. Hawai`i archives, data reduction including improvements to the current algorithms, and application of both the statistical and "MCC" analysis approaches. The candidate will be working closely with both Dr. Leka and Dr. Longcope, as well as colleagues at the University of Hawai`i. Travel between Colorado, Hawai`i and Montana is part of the package. The position is currently funded for just over one year, with possible additional funding pending. The candidate would be expected to spend approximately 10% of their time helping to write proposals for additional funding on projects related to the one outlined herein and other topics of their interest.