I tried and I got a ridiculous large number for the neutrino mass. I basically used [tex]E=\gamma m c[/tex] and then, for 10 MeV neutrinos, time taken is t + 10 seconds to reach Earth, for 50 MeV neutrinos, time taken is t seconds.(adsbygoogle = window.adsbygoogle || []).push({});

[tex]Speed = \frac{100 000}{(t+10)}[/tex] for 10 MeV and [tex]Speed = \frac{100 000}{t}[/tex] for 50 MeV. Here's the question:

Neutrinos were detected from a supernova (distance ~ 100 000 light years) over a time period of ~ 10 seconds. The neutrinos have an energy range from 10 MeV to 50 MeV.

What's the mass of the neutrino, assuming all neutrinos were produced at the same time and their mass is small compared to their energy.

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# Neutrino mass

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