CEDAR email: Physics of Incoherent Scatter, Arecibo Observatory Colloquium on Sep. 29

[Jens Lautenbach]

Dear CEDAR community,

The Arecibo Observatory Colloquium Series presents on September 29, 2020 2:00PM (AST) the talk:

"The Physics of Incoherent Scatter with Application to the Understanding of the Plasma Line Spectrum with Narrow Peaks in the Electron Velocity Distribution Function" by Dr. Michael Sulzer from the Arecibo Observatory - UCF, Space and Atmospheric Sciences group, Arecibo, Puerto Rico, US.

The colloquium will be streamed via Zoom (https://zoom.us/)<https://ucf.zoom.us/j/97529242519> or join by phone: +1 929 205 6099, conference ID: 975 2924 2519. Further information can be found at the Colloquium Series Website<https://nam02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.naic.edu%2Fpkg%2Fwebutils%2Fseries%2F%23.%2Fpages%2Fblog%2Fphysics-of-incoherent-scatter.html&data=02%7C01%7CJens.Lautenbach%40ucf.edu%7C398d1563dbfe4677b0c408d85ff6ad11%7Cbb932f15ef3842ba91fcf3c59d5dd1f1%7C0%7C0%7C637364860373177112&sdata=7Re8R%2F1pHVMpAvAGXXqAvrq0GLW0YI4mpcfY%2FwzHjPU%3D&reserved=0>. If you like to join the Arecibo Observatory Colloquium mailing list please see this page<https://areciboobservatory.us4.list-manage.com/subscribe?u=3057031f1c6bb49feeefdf63d&id=a7d471a7b5>.

Abstract:
Incoherent scatter is a very useful diagnostic of the ionospheric plasma. A theoretical description of the scattered spectrum  has been available for several decades, describing all the features, ion, plasma, and gyro lines, including the possibility of both Maxwellian and non-Maxwellian particle velocity distributions.  Recently Djuth and Carlson (2018) identified features in the plasma line spectrum that they convincingly attributed to narrow peaks in the electron velocity distribution function caused by the solar ionizing EUV radiation.  The observed features had unexpected narrow valleys in the spectrum as well as peaks, and all the features had unexpected frequency locations. However, the equations describing the incoherent scatter spectrum do predict the observed behavior of these features, but this alone is not completely satisfying.
In this talk we review the physical principles of incoherent scatter, considering in particular two limiting cases, first with the radar looking along the earth's magnetic field, and second with very high gyro frequency.  Then we show that the characteristics of these observed features are, from this point of view, expected.


Best regards,

Dr. Jens Lautenbach
Observatory Scientist
Arecibo Observatory - University of Central Florida
Space & Atmospheric Sciences
HC-3 BOX 53995
Arecibo, Puerto Rico 00612

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://mailman.ucar.edu/pipermail/cedar_email/attachments/20200924/6772ec67/attachment.html>