If you’re talking about the neutron it’s because concrete has a lot of hydrogen. Alpha particles, beta particles, and light (gamma rays in this picture) interact with electrons, with the probability of being stopped increasing with electron density. Lead has a lot of electrons (its lower on the periodic table, called a “high z” element).
Neutrons, however, don’t care about electrons and instead interact with the nucleus, with the probability of being stopped depending on the spin state of the nucleus and the neutron. This doesn’t follow a specific pattern on the periodic table, but hydrogen has a big chance of interacting with the neutron while lead doesn’t. Cadmium, boron, and I think lithium 7 also would stop neutrons easily (there are more of course but those are what I remember offhand).
Nah, that’s not what they’re talking about. Superman’s vision is capable of penetrating concrete, but gets reliably stopped by lead. None of the particles here (or, I’m guessing, anywhere) have that property.
What prevents Superman from being able to see through lead but not concrete?
Narrativium
Comic book authors
If you’re talking about the neutron it’s because concrete has a lot of hydrogen. Alpha particles, beta particles, and light (gamma rays in this picture) interact with electrons, with the probability of being stopped increasing with electron density. Lead has a lot of electrons (its lower on the periodic table, called a “high z” element).
Neutrons, however, don’t care about electrons and instead interact with the nucleus, with the probability of being stopped depending on the spin state of the nucleus and the neutron. This doesn’t follow a specific pattern on the periodic table, but hydrogen has a big chance of interacting with the neutron while lead doesn’t. Cadmium, boron, and I think lithium 7 also would stop neutrons easily (there are more of course but those are what I remember offhand).
Nah, that’s not what they’re talking about. Superman’s vision is capable of penetrating concrete, but gets reliably stopped by lead. None of the particles here (or, I’m guessing, anywhere) have that property.
Gamma rays kinda do, you need 10x more concrete to block them than lead: https://en.wikipedia.org/wiki/Half-value_layer
Phew, good to know. I was beginning to think Superman isn’t real.
Gammas might be able to penetrate a little bit of concrete, since concrete has lower electron density than lead
what do neutrons care about though? how do we appeal to that demographic?
https://media1.tenor.com/m/mijyy4ehvEkAAAAd/ill-try-spinning-spinning.gif