Incorrect barycentric correction

Message boards : Nebula : Incorrect barycentric correction
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Profile David Anderson
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Message 1833607 - Posted: 2 Dec 2016, 7:58:22 UTC

The Arecibo telescope is accelerated by the Earth's rotation and by the gravitational pull of the Sun and the planets. These various accelerations cause drift in the detected frequency of an ET signal. Fortunately, it's possible to calculate this offset and subtract it from the detection frequency; this is called the signal's "barycentric frequency".

Eric Korpela recently discovered that we were doing this wrong; essentially, we were adding instead of subtracting. D'oh! We're in the process of fixing this in the Nebula code, and future multiplet-finding will use the correct frequencies.
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Profile Raistmer
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Message 1833614 - Posted: 2 Dec 2016, 9:46:26 UTC - in response to Message 1833607.  

Has this any relation to client/frontend code? If yes, was it fixed in SETI MultiBeam v7 to v8 transition?
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Message 1834237 - Posted: 5 Dec 2016, 6:51:01 UTC - in response to Message 1833614.  

It's not part of the front-end code.
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Profile Chris SCrowdfunding Project Donor
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Message 1836547 - Posted: 17 Dec 2016, 19:13:44 UTC

Eric Korpela recently discovered that we were doing this wrong; essentially, we were adding instead of subtracting.

I'm really pleased that Eric nas been given full credit for that :-)
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Message boards : Nebula : Incorrect barycentric correction


 
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