The low-energy s-wave limit for the given square-well potential reduces to the form shown in option B, as indicated by the provided expressions and the answer key.

The Sun's energy is generated by nuclear fusion reactions in its core.

Yukawa proposed that nuclear forces are mediated by mesons (pions) exchanged between nucleons.

By definition, a nucleus with a bound hyperon is called a hyperfragment; the other choices are not standard terms.

Each electron (or positron) has rest energy ~0.51 MeV, so the pair has twice that, about 1.02 MeV.

For a meson at rest decaying into two photons, conservation of momentum requires the photons to be emitted in opposite directions (option C).

A helium nucleus (alpha particle) consists of two protons and two neutrons, so it does not contain two electrons.

The OCR answer hint for this block indicates option B as correct according to the scanned material.

Crystallography uses X-ray analysis to determine crystal structures and analyze material properties.

In a solid metal, atoms vibrate about equilibrium positions rather than moving freely.