For folks who want my take on the announcement today by #xenon1t that they may have detected solar axions, I gave comments to @RafiLetzter of @LiveScience yesterday: https://www.livescience.com/first-evidence-for-axions-xenon.html

Watch the talk in real time here: https://efi.uchicago.edu/events/event/1361/

Truly tragic that this announcement is coming just a week or so after Roberto Peccei passed away. Thrilled that I got a warm email from Helen Quinn about #Strike4BlackLives last week.

Axions are a product of the Peccei-Quinn mechanism.

What I'm getting from this talk is that there are a lot of background issues that make it complicated to be sure about what's happening here. This is potentially exciting, but I remain skeptical and look forward to more data, collected independently.

I'm personally concerned that the stellar constraint line is missing from the top plot in figure 10 here. We have constraints on ALPs from neutron star cooling, supernovae, and red giants: https://www.science.purdue.edu/xenon1t/wp-content/uploads/2020/06/xenon1tlowersearches.pdf

h/t to Sam McDermott for finding plots 4 and 5 in this paper, which highlights, for example, the red giant limit: https://arxiv.org/pdf/2004.08121.pdf

In @RafiLetzter's article a scientist says this wouldn't solve the strong CP problem, but in fact if the detection is real, the QCD axion could be these solar axions. So that comment in the article is wrong. (Not sure how much the commentator knew about results when he made it.)

Mentioned in the talk . . . there is tension with stellar constraints. But they don't really say this in the paper?!? Actually instead they kind of wave the stellar constraints off.

Which reminds me: this paper is not peer reviewed yet! (I would have done that b4 announcing...)

Right now, solar axions (new big deal physics) are only slightly preferred to tritium and neutrinos (known physics)