https://hackerpaper.kaipfister.de/p/1410.8530/Collected HN comments and submissions linking this paper.enMon, 02 Nov 2026 11:16:22 GMThttps://news.ycombinator.com/item?id=35548220urn:hackerpapers:mention:1410.8530:35548220Wed, 12 Apr 2023 22:59:38 GMT<p>In this case they are detecting inverse beta decay events. The antineutrino interacts with a proton producing a positron and a neutron. The positron annihilates with an electron producing two gamma rays and the neutron then captures on a proton and releases a 2.22 MeV gamma ray. I think the only realistic way to determine the direction is by looking at the direction of the neutron by comparing the position of the positron annihilation with the neutron capture, but typically the neutron scatters so much in these detectors that it is not possible to do on an event by event basis (although see…</p><p><a href="https://hackerpaper.kaipfister.de/p/1410.8530/">Paper and discussion history</a>. A mention is not an endorsement.</p>physics.ins-det