Viper Transmission Calculation
To calculate Viper transmission, what was needed was a
measurement of incident power to the dewar, as well as received power to
the dewar. The ratio should be the transmission.
Using 13 different observations of Ngc6334, the incident flux was
calculated, taking into account atmospheric absorbtion. The next step was
to calculate the power incident to the .7 m diameter of the primary
that is illuminated, taking into account the large frequency bandwidth,
6.68 E10 Hz.
To calculate the incident power to the dewar, this was multiplied by .75
to correct for the transmission of the filter, multiplied by .8 to correct
for the transmission of the pressure window, and multiplied by .85 to
correct for the amount of time the chopper spends on source.
Next to calculate was the recieved power. Every measurement is given in
terms of the integ-unit, which, because of the electronics involved,
corresponds to about 1.83 E-16 W. Then, correcting for the preamp gain
of 10000 and the 1.3% transmission of the dewar, a received power
was calculated.
The average ratio of the received power to the incident power is
49.08%.
Another calculation was made using SgrB2, using the same methodology, of
46.06%