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Physics Girl: Super-Kamiokande – Imaging the sun by detecting neutrinos [video]

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Re: Physics Girl: Super-Kamiokande – Imaging the sun by detecting neutrinos [video]

#61

Is this long Covid or depression or Major Depressive Disorder (MDD)? Because in her earlier videos she talks about becoming bed-bound again due to her emotional state after finding news her friend who had a similar condition died.

Dunno, personally I don't think its that much of my business. Sure I'm curious, but that doesn't mean I have a right, or that its a nice thing™ to publicly speculate

She’s been pretty open about it. She even touched on it at the end of this video.

Re: Physics Girl: Super-Kamiokande – Imaging the sun by detecting neutrinos [video]

#62
post #45

video about her long-covid battle and recovery here: https://www.youtube.com/watch?v=vqeIeIcDHD0 (caution for those currently sick as it's a rough watch at first)

I know someone whose CFS is about 10% of hers and it was still a rough watch. She got hit really fucking hard.

Re: Physics Girl: Super-Kamiokande – Imaging the sun by detecting neutrinos [video]

#63
post #34

Earlier quoted context omitted.

It's not the same photon though. The fusion happens in the core, then takes millennia for the energy to escape. During that time photons are emitted and absorbed by the atoms, until the surface emits one that finally travels to the earth in 8 minutes. Anyway that's taking you from the ELI5 to the ELI9 version. I'm sure someone on here can correct it further.

I haven’t tried to look up the history of this claim, but here are some guesses: 1. There’s a sort of diffusion process going on. Photons from the core have some mean free path as a function of radial position (and, obnoxiously, of wavelength as well, so maybe we ignore that). You could calculate the mean time for a hypothetical object emitted from the core and traveling according to those mean free paths to escape.…

The canonical Q/A pair "Why does the Sun shine?"/"Fusion in its core" perhaps contributes confusion here? Where the question is silently swapped out for "Why is the Sun still shining after 4+ Gyr?". You're primed for a close connection between core and surface photons. Asking "Why is there fog over the uncovered corner of the pool?", one seems unlikely to appreciate "the fog comes from a small aquarium heater somewhere on the bottom!" (IIRC the magnitudes). "The Sun is hot, and hot things glow" creates less of that association between core and light.

> You could calculate how long it would take to notice anything if the core suddenly stopped fusing.

FW(little)IW (very not my field, just AI, quick&sloppy), for a Sun magically switched to contraction-dominated heating, I'm sloping order 10^6-7 yr for a 1% increase in surface temp, with core contraction dynamics being just one uncertainty.

Re: Physics Girl: Super-Kamiokande – Imaging the sun by detecting neutrinos [video]

#65
post #60

I think Super-K is the place with water so pure that it will leach pretty much anything which was discovered when one of the tech's hair got wet while leaning over the water. The hair looked bleached after it went into the water. My googlfu is not finding anything to confirm though

Isn’t that also the one where a sensor imploded and caused a chain reaction that destroyed like a third of the other sensors?

Yes, except about half. This[1] article goes into how and why, without the fluff.

The chain reaction escalated uncontrollably, and within ten seconds, approximately 6,800 of the 11,129 PMTs were destroyed.

[1]: https://physicscommunication.ie/neutrino-detector-in-peril-t...

Re: Physics Girl: Super-Kamiokande – Imaging the sun by detecting neutrinos [video]

#66

The video mentions that this image was taken during the night time. If the neutrinos do not interact with the entire Earth on their way through, then how do they interact with the sensor?

Watch the video

Re: Physics Girl: Super-Kamiokande – Imaging the sun by detecting neutrinos [video]

#67

The video mentions that this image was taken during the night time. If the neutrinos do not interact with the entire Earth on their way through, then how do they interact with the sensor?

Watch the video

Thanks. I watched half the video, but couldn't finish it. Now that I've finished it I see that the neutrinos interact with water in the tank.

Thirty interactions on average per day, that's crazy - earlier in the video the host mentions that the cross section of a thumbnail has a billion neutrinos flowing through every second!

Re: Physics Girl: Super-Kamiokande – Imaging the sun by detecting neutrinos [video]

#68

I think Super-K is the place with water so pure that it will leach pretty much anything which was discovered when one of the tech's hair got wet while leaning over the water. The hair looked bleached after it went into the water. My googlfu is not finding anything to confirm though

Reminds me of the scene in Kung Panda 1 where one feather of the goose, Peng, falls into the tunnel which Tai Lung uses to unlock his cage and escape.

Re: Physics Girl: Super-Kamiokande – Imaging the sun by detecting neutrinos [video]

#70
It's a giant long term project with a fascinating history and engineering. One notable event which is interesting from engineering perspective was a catastrophic failure of roughly half tubes in 2001. It took them five years to fully restore 6K tubes.
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