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PhonAcq
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Message 1176981 - Posted: 10 Dec 2011, 3:34:50 UTC

Would someone explain to me why MB's are so dominant in the work stream? I have set my profile to prefer AP's, but I rarely get any; some but not a lot. I'm sure this is well know, so perhaps someone could refresh the explanation.

When AP came out, it was described as having more science content (obviously paraphrasing here). So by now, I would have thought we would see a whole lot more AP wu's.

Josef W. Segur
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Message 1176985 - Posted: 10 Dec 2011, 4:08:11 UTC - in response to Message 1176981.

Would someone explain to me why MB's are so dominant in the work stream? I have set my profile to prefer AP's, but I rarely get any; some but not a lot. I'm sure this is well know, so perhaps someone could refresh the explanation.

When AP came out, it was described as having more science content (obviously paraphrasing here). So by now, I would have thought we would see a whole lot more AP wu's.

Astropulse WUs are 13.42 seconds of the full 2.5 MHz recorded bandwidth. A "tape" file of 50.2 GB holds about 1.5 hours of recorded data, so one channel produces about 400 WUs. MB WUs have 1/256 the bandwidth, so although they last 8 times as long there are a lot more of them derived from the same data, and because subsequent groups of 256 are overlapped by nearly 21 seconds with the previous group there are about 15872 MB WUs from one channel. For good clean data which can be split both ways, the ratio is very near 40:1 MB:AP.

I don't think AP was ever described as having more science content than S@H Enhanced, but it adds to the science content derived from the recorded data.
Joe

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Message 1177150 - Posted: 10 Dec 2011, 22:13:35 UTC

Joe, the following is from the Astropulse FAQ page. You are right, they don't explicitly claim to do more science, but the wording is highly suggestive of doing so.


What else might Astropulse find?
In addition to ET, Astropulse might detect other sources, such as rapidly rotating pulsars, exploding primordial black holes, or as-yet unknown astrophysical phenomena.

You can imagine that SETI@home is a search for a gold needle (ET) in a haystack. During the search for a gold needle, Astropulse might occasionally find a silver needle (a pulsar or black hole.) These silver needles have their own scientific value, even if they don't represent extraterrestrial communications.

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Message 1177155 - Posted: 10 Dec 2011, 22:37:45 UTC - in response to Message 1176985.
Last modified: 10 Dec 2011, 22:51:19 UTC

Would someone explain to me why MB's are so dominant in the work stream? I have set my profile to prefer AP's, but I rarely get any; some but not a lot. I'm sure this is well know, so perhaps someone could refresh the explanation.

When AP came out, it was described as having more science content (obviously paraphrasing here). So by now, I would have thought we would see a whole lot more AP wu's.

Astropulse WUs are 13.42 seconds of the full 2.5 MHz recorded bandwidth. A "tape" file of 50.2 GB holds about 1.5 hours of recorded data, so one channel produces about 400 WUs. MB WUs have 1/256 the bandwidth, so although they last 8 times as long there are a lot more of them derived from the same data, and because subsequent groups of 256 are overlapped by nearly 21 seconds with the previous group there are about 15872 MB WUs from one channel. For good clean data which can be split both ways, the ratio is very near 40:1 MB:AP.

I don't think AP was ever described as having more science content than S@H Enhanced, but it adds to the science content derived from the recorded data.
Joe



That's exactly how AstroPulse work has been described, enhanced,
maybe added
, is a better word. But not having more scientific content then MultiBeam work.
It's the same data, but bigger chunks and it's (pre-)processed in a different way.
If I'm not terribly mistaken...
And they are more broadbanded, so they can detect other signals compaired to the 1.4xxxxxGHz.(H2-resonance,
water-hole, band, which is obviously, very small, (-18dB/KHz.)(?)).
(Don't see them very much, though............no chance of gettin through..:)
____________


Knight Who Says Ni N!, OUT numbered.................

Message boards : Number crunching : Astropulse Refresh

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