Faraday Rotation Observations of the Extragalactic Radio Source 1741-038 During an Extreme Scattering Event
Session 36 -- ISM: Structure, Molecular Clouds
Display presentation, Wednesday, June 14, 1995, 9:20am - 6:30pm

## [36.06] Faraday Rotation Observations of the Extragalactic Radio Source 1741-038 During an Extreme Scattering Event

Andrew W. Clegg (Naval Research Laboratory), Alan L. Fey (U.S. Naval Observatory), R. L. Fiedler (Naval Research Laboratory)

The extragalactic radio source 1741-038 underwent an extreme scattering event in 1992. During the middle of the event, and 1.5 years after the end of the event, we obtained Faraday rotation observations of this source. The results are consistent with no change in rotation measure during the scattering event. Based on previous models of the scatterer, we constrain the parallel component of the magnetic field within the scatterer to between 5 $\mu$G and 1 mG. While the general interstellar field is substantially less than these constraints (about 2 $\mu$G), the field strength within a scatterer is expected to be greatly increased over typical interstellar values if the scattering medium is, as suggested by many models, the result of plasma density enhancements due to a passing shock.