
TY  - JOUR
A1  - Cim&ograve;, Giuseppe 
A1  - Beckert, T. 
A1  - Krichbaum, T. P. 
A1  - Fuhrmann, L. 
A1  - Kraus, A. 
A1  - Witzel, A. 
A1  - Zensus, J. A. 
T1  - A Very Rapid Extreme Scattering Event in the IDV Source 0954+658
JF  - Publications of the Astronomical Society of Australia
JO  - Publ. Astron. Soc.  Aust.
Y1  - 2002
VL  - 19
IS  - 1
SP  - 10
EP  - 13
KW  - quasars: individual (0954+658) &#8212; ISM: structure
UR  - https://doi.org/10.1071/AS01097 
N2  - Extreme scattering events (ESEs) are dramatic variations of the flux density at gigahertz frequencies caused by ray path distortions within an isolated inhomogeneity (&#8216;plasma lens&#8217;) in the interstellar medium. These events are characterised by a deep flux density minimum in the light curve with, in some cases, surrounding maxima. The variability time scales range from weeks to months. These phenomena show a strong frequency dependence, in which the variability amplitudes increase with wavelength. During an intraday variability (IDV) monitoring project (March 2000), a feature resembling an ESE-like event appeared in the variable light curve of 0954+658, however with a time scale of less than two days. We will discuss this effect and its implications for a better description of the interstellar medium. 
ER  -

