A radioactive source emits a collimated beam containing alpha (α\alphaα), beta-minus (β−\beta^-β−), and gamma (γ\gammaγ) radiation into a region of uniform magnetic field directed perpendicularly into the page, as shown in the diagram below.
Which of the following statements is correct regarding the emissions XXX, YYY, and ZZZ?
ZZZ consists of α\alphaα-particles because their greater charge (+2e+2e+2e) causes a stronger magnetic force, leading to a much sharper curve.
YYY consists of γ\gammaγ-radiation, which has the greatest penetrating power and can be completely stopped by a thin sheet of aluminium.
XXX consists of α\alphaα-particles and has the greatest ionizing power of the three emissions.
XXX consists of β−\beta^-β−-particles because a negative charge experiences an upward magnetic force when moving perpendicular to a magnetic field pointing into the page.