<html><head></head><body><div style="font-family:lucida console, sans-serif;font-size:13px;"><div>Hey all, <br><br>The paper for next week's journal club is titled "Measurement of the neutron lifetime using an asymmetric magneto-gravitational trap and in situ detection", and is attached. It can also be found here: https://arxiv.org/abs/1707.01817 . The paper details a major result from the UCNtau collaboration, so it will surely be published somewhere real pretty soon. <br><br><br>Questions for reading and/or discussion: <br><br>* What are "quasi-trapped" neutrons, and why is it important to avoid them?<br>* Why use both a magnetic Halbach array and an additional magnetic holding field?<br>* Why pair the runs up into sets of long and short runs?<br>* Is this result good enough to extract any further constraints on cosmological or BSM physics? <br>* Does this result actually resolve the long held discrepancy between neutron lifetime measurement techniques?<br><div><br></div><div><br></div><div>Cheers, </div><div><br></div><div>- Melissa<br></div><br></div></div></body></html>