[evlatests] Temperature-Dependent Gains at P-band...

[Rick Perley]

     Indeed -- but hard to understand how that would translate into an 
unusual temperature sensitivity ...  The observations were mostly at 
night, with ideal weather conditions...

     Antennas 1, 2 and 24 were adjacent (W6, W4 and W8 respectively), 
while ea28 was down the arm a bit, at W14.

     Rick


On 02/14/2019 11:05 AM, Dan Mertely wrote:
> Hi Rick. I notice that all 4 antennas referenced are on the
> west arm.  -Mert
>
> On 2/14/2019 9:07 AM, Rick Perley wrote:
>>      In reviewing the data from the lunar polarization experiment, I 
>> note that some antennas have a very strong temporal variation in 
>> their gains.  These changes are as large at 75%, are quite slow, and 
>> seem highly correlated with temperature -- for all the affected 
>> antennas, the maximum gain occurred at ~6AM, when temperatures were 
>> coldest.
>>
>>      The most strongly affected antennas are:
>>
>>      ea02 (max/min power ratio = 1.75)
>>
>>      ea01 (1.50)
>>
>>      ea24 (1.40)
>>
>>      ea28 (2.0 -- although the time dependency for this one is not 
>> the same as the others).
>>
>>      For all, the rise and fall of the power is gradual.  And for 
>> all, the switched power values seem to perfectly track the gain 
>> changes (as they should!).
>>
>>      Why should these antennas be (apparently) temperature sensitive, 
>> while the others are not?
>>
>>      Rick
>>
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