Solar Neutrino Measurements in Super-Kamiokande-IV · HackerPapers discussions

Solar Neutrino Measurements in Super-Kamiokande-IV — mentioned by 0PingWithJesus

Mon, 15 Jun 2020 21:38:00 GMT

For their more recent data they reported seeing ~32000 solar neutrino events over a 1600 day dataset (cite: top-right of page 13 https://arxiv.org/pdf/1606.07538.pdf). Their detector nowadays is more sensitive than it was when the OP was published so I would estimate the image comes from probably around 5000 neutrino events. And I don't know any specific numbers but you can be sure a large amount more of neutrinos interacted with the air/rock between the Sun and Super-K than interacted in the detector volume. But that number (whatever it is) is still tiny compared to the total flux (which is…

Paper and discussion history. A mention is not an endorsement.

Solar Neutrino Measurements in Super-Kamiokande-IV — mentioned by 0PingWithJesus

Mon, 15 Jun 2020 17:28:59 GMT

The detector does not "look" in any direction, it is in no way "pointed" at the sun. It records the direction of all events that occur within its volume. But once recorded they compare the direction of all events with the direction from the sun at the time of the event. The angle between the solar direction and the event direction is what makes up that image. If the neutrinos were not coming from the sun, the image would look like white-noise. Since there is a clear "peak" at the center you can make a good estimate about what fraction of events in your data set came from the sun. That amount…

Paper and discussion history. A mention is not an endorsement.

Solar Neutrino Measurements in Super-Kamiokande-IV — mentioned by 0PingWithJesus

Mon, 15 Jun 2020 16:20:15 GMT

This article is quite old but a more recent measurement from the same experiment (Super-K) used a 1600 day dataset. Of that 1600 days of exposure 860 "days" were nights. So it's pretty close to half and half. (Cite: Section V-B, bottom left of page 22, of https://arxiv.org/pdf/1606.07538.pdf ) The daytime data and night time data are decoupled quite easily. Whenever an event is recorded by the detector you just make sure a timestamp is associated with the event. Then you use that timestamp to determine the location of the sun at the time of the event. If the sun is below the horizon it's…

Paper and discussion history. A mention is not an endorsement.