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Interactive MU Model - Online Computations and Plots
Virtual MU Radar - Realtime Ionosphere Prediction
MU Radar IS Observation and Data

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The MU (Middle and Upper atmosphere) radar (34.8N, 136.1E) is a 46.5-MHz,
pulse-modulated, monostatic, Doppler radar with an active phased-array
antenna which consists of 475 Yagis. This MST radar is also designed to be
able to observe the weak incoherent scatter (IS) from free electrons of
the ionosphere. Measurements are made at 4 beam directions simultaneously.

The MU Radar Ionosphere Model is based on the MU radar IS experiments
taken between 1986 - 2003, and archived in the Madrigal Database (http://www.openmadrigal.org). So
far models for electron density, ion and electron temperature have been
created, using a bin-fit technique, similar to what has been used for the
local Millstone Hill models. Details of the technique have been given
in *Regional and local ionospheric models based on Millstone Hill
incoherent scatter radar data*, Geophys. Res. Lett., 29(8),
10.1029 / 2002GL014678, 2002. (PDF
file),
and in *
Local Empirical Model of the E and F Region Ionosphere Based on 30 Years
of Millstone Hill Incoherent Scatter Data *

The data were binned by month and local time in 1-hour increments. Least
squares fits for model parameter profiles were then computed in each of
the 12x24=288 bins. Ne profiles are piecewise-linear with 30 nodes between
200 - 600 km at 10 km spacing giving a fine height resolution, while Te
and Ti profiles have 9 nodes at 228.50, 273.60, 318.70, 363.80, 408.90,
454.00, 499.10, 544.20, 589.30 km for which altitudes MU radar temperature
data are always given. To increase the amount of data into statistics,
each of the 12 monthly bins contains 3 month data from the current month
plus before and after the month. There are relatively small amount of Te
and Ti data which have been obtained from the separated 4-pulse
experiments from the Barker-coded pulse Ne profile experiments. So for the
temperature models, we have included data within 3 hours for each hourly
bin, e.g., for the 1200LT bin, data are from 1000-1300 LT.

The parameters are assumed to be linear in F10.7 for the previous day and
the Ap index for the previous 3 hour period. The least squares fit yields
model coefficients for each parameters. A 3×3 median filter in local time
and season is then applied to these coefficients.

The model can be provided to interested users with recovery FORTRAN codes
and coefficient data files. It is also available for online interactive
calculations and plots; the URL is
http://madrigal.haystack.edu/models/MUisrm_form.html. Based
on
near realtime solar geophysical indices, a Virtual MU Radar (VMUR) is
created which predicts the ionospheric conditions for Ne, Te and Ti at
current local time as well as for the whole day at Shigaraki. The VMUR is
at
http://madrigal.haystack.edu/models/vmur/. Please contact Shunrong Zhang or John Holt for more details
about the model.

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The Middle and Upper Atmosphere (MU) radar belongs to and is operated by the
Radio Science Center for
Space and Atmosphere, RASC (now
Research Institute for Sustainable Humanosphere, RISH) of Kyoto University.
The MU radar data has been obtained from Dr. Kawamura, and installed into
and maintained with the MADRIGAL
system at MIT Haystack Observatory.
The Millstone Hill
incoherent scatter radar is supported by a cooperative agreement
between the National Science Foundation
and the Massachusetts Institute of
Technology.
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This project is based upon work supported by the National Science Foundation under Grant
Number 0207748.
Any opinions, findings, and conclusions or recommendations expressed
in this material are those of the author(s) and do not necessarily reflect
the views of the National Science
Foundation.