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Biggest dark matter detector spots a single weird particle

science.org

21–30 of 152 posts

Re: Biggest dark matter detector spots a single weird particle

#21

I read their preprint[1] and they did a thorough job. They investigated a number of the things I'd suspect if I were looking for mis-reconstructed events or weird backgrounds. So it's certainly interesting! That said, particle physics history is full of 3 sigma particle "discoveries" that disappeared with more data. They're collecting more, so hopefully we'll learn more in a few more years. [1] https://lz.lbl.gov/wp-…

This sort of thing is really useful for helping people to understand what the purpose of scientific publication is. It's not about presenting finished products to society, it's more like a Discord where you communicate new findings with other authors. Often the reason for a communication is because you found something weird, and you want other people to know about it so they can help you confirm or rule it out as bad data. People shouldn't feel gunshy about this. (My field even has a conference for failed results, CFAIL.) I like to highlight examples of this stuff, because I see so many angry online comments when a paper turns out to be "wrong" or doesn't replicate.

Re: Biggest dark matter detector spots a single weird particle

#22

I read their preprint[1] and they did a thorough job. They investigated a number of the things I'd suspect if I were looking for mis-reconstructed events or weird backgrounds. So it's certainly interesting! That said, particle physics history is full of 3 sigma particle "discoveries" that disappeared with more data. They're collecting more, so hopefully we'll learn more in a few more years. [1] https://lz.lbl.gov/wp-…

This sort of thing is really useful for helping people to understand what the purpose of scientific publication is. It's not about presenting finished products to society, it's more like a Discord where you communicate new findings with other authors. Often the reason for a communication is because you found something weird, and you want other people to know about it so they can help you confirm or rule it out as bad…

You have accurately described a email mailing list. Where in the value-add here?

Re: Biggest dark matter detector spots a single weird particle

#23

Earlier quoted context omitted.

This sort of thing is really useful for helping people to understand what the purpose of scientific publication is. It's not about presenting finished products to society, it's more like a Discord where you communicate new findings with other authors. Often the reason for a communication is because you found something weird, and you want other people to know about it so they can help you confirm or rule it out as bad…

You have accurately described a email mailing list. Where in the value-add here?

You think that people's findings should be communicated by email? that their email chains are what should go into the permanent record and be cited and printed out and included in journals and such?

would you include all the quoted text in the reply-alls, or is that too much?

Re: Biggest dark matter detector spots a single weird particle

#24

So you have 7 tons of Xenon as the detector, hoping that some dark matter will bump into a nucleus. How do you exclude other effects?

To start with, they do a lot of work to eliminate radioactive backgrounds in the materials they're using, and they put the detector deep underground to shield from cosmic rays. Additionally, when a particle interacts with the nucleus, the ratio of how much energy ends up as scintillation light versus ionization is different than when a particle interacts with an electron, which is most of the background processes. Th…

Yeah, it's funny, for experiments like this you spend 90% of your time modeling and subtracting noise, and 10% analyzing the signal that results. Had the same experience in X-ray astronomy. 3 years building a detailed model of all the sources of noise, then subtracting it out and finally starting on the science.

Re: Biggest dark matter detector spots a single weird particle

#25

Earlier quoted context omitted.

I agree. Moreover, I'm not sure if it's the same team, but in a similar experiment while removing all the other effects, they discovered that Xenon 124 is radioactive, but the half life is super long and no one had seen it before. https://xenonexperiment.org/observing-the-rarest-decay-proce...

That's a pretty cool discovery in its own right.

Wow! That's in https://en.wikipedia.org/wiki/Xenon now.

Xe-124, half-life 1.1 * 10^22 years. That's crazy.

Re: Biggest dark matter detector spots a single weird particle

#26

I read their preprint[1] and they did a thorough job. They investigated a number of the things I'd suspect if I were looking for mis-reconstructed events or weird backgrounds. So it's certainly interesting! That said, particle physics history is full of 3 sigma particle "discoveries" that disappeared with more data. They're collecting more, so hopefully we'll learn more in a few more years. [1] https://lz.lbl.gov/wp-…

This sort of thing is really useful for helping people to understand what the purpose of scientific publication is. It's not about presenting finished products to society, it's more like a Discord where you communicate new findings with other authors. Often the reason for a communication is because you found something weird, and you want other people to know about it so they can help you confirm or rule it out as bad…

They were - in the past. I imagine that right now, Discord is their Discord.

Re: Biggest dark matter detector spots a single weird particle

#27

Earlier quoted context omitted.

This sort of thing is really useful for helping people to understand what the purpose of scientific publication is. It's not about presenting finished products to society, it's more like a Discord where you communicate new findings with other authors. Often the reason for a communication is because you found something weird, and you want other people to know about it so they can help you confirm or rule it out as bad…

You have accurately described a email mailing list. Where in the value-add here?

Instead of reading everybody's spam or having to have a centralized body decide who gets to send messages to the mailing list, journal editors filter which things are worthy of publication and in which journal such that readers don't have to wade through garbage or uninteresting results.

Re: Biggest dark matter detector spots a single weird particle

#29

Earlier quoted context omitted.

Are there any other candidate particles besides WIMPs that the observation could be from, assuming it’s a real signal?

In one sense anything that passed all their background rejection is a WIMP. To interact with a nucleus through so much matter, it's not interacting electromagnetically. The main candidate for a strong force interaction would be a neutron, and they did a lot of work to model that and eliminate it as a background. So definitionally it would be a WIMP. They were pretty model agnostic in what they were looking for. They…

If neutrons are on the list, how are they ruled out from a random decay event emitting particles, from some mineral in the surrounding rock?

Re: Biggest dark matter detector spots a single weird particle

#30
I think it's cool that there's still unconfirmed hypothesizes, and still unexplained phenomena in the science that's investigating these hypothesizes.

I hope this turns into a real discovery about something; but even if it's an equipment malfunction, hopefully it's a lesson that can be turned into improving the detector.

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