How to show 400 neutrinos are present?

Thread starter hraghav
Start date Nov 18, 2024
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Calculation Detection Neutrinos

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To demonstrate the presence of 400 neutrinos, the calculation starts with detecting 12 neutrinos per 3 million kg of water, resulting in a detection rate of 4*10^-6 neutrinos per kg. When scaled to the weight of a human eyeball, approximately 0.01 kg, this equates to 4*10^-8 neutrinos per eyeball. The poster struggles to scale this data effectively to reach a total of 400 neutrinos, having arrived at values of either 3.69*10^9 or 4*10^-8 neutrinos. The discussion also touches on the number of human eyeballs present in 1987, indicating a broader inquiry into neutrino detection methods. Assistance is requested to clarify the scaling process to achieve the target of 400 neutrinos.

Nov 18, 2024

hraghav

Homework Statement: Twelve electron neutrinos from SN 1987A were detected at Kamiokande in Japan. This
experiment consisted of a tank filled with 3x10^6 kg of water and surrounded by photomultiplier tubes to detect the Cerenkov radiation. Scale this to show that about 400 neutrinos could have been “seen” by humans, if we assume that eyeballs are composed primarily of water and weigh about 10 g each.

Relevant Equations: 12/3*10^6 kg
4*10^-6 neutrinos * 0.01kg

Number of neutrinos detected per kg of water = 12/3*10^6 kg = 4*10^-6 neutrinos
Neutrinos detected by 1 eyeball = 4*10^-6 neutrinos * 0.01kg = 4*10^-8 neutrinos

I am not sure how to scale this to get 400 neutrinos. I did try multiple ways but either ended up with 3.69*10^9 or 4*10^-8 neutrinos. Could someone please help me with this. Thanks!

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Nov 18, 2024

Orodruin

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How many (human) eyeballs in 1987?

Nov 18, 2024

WWGD

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Roll call on neutrinos.

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