Lepton number, family number, and where family number fails

What endpoint energy does a calibrated spectrum from a sealed beta source support, and how much energy per decay is unaccounted for if nothing but an electron leaves? Useful evidence includes an energy calibration from a conversion-electron line such as Bi-207 or Cs-137, a background-subtracted spectrum, a Kurie fit with an interval on the endpoint compared with the tabulated Q value, and detector resolution and backscatter named as the limit that blocks any neutrino-mass claim.

This GioPhysics course map is an adaptable learning sequence, not academic credit, accreditation, or a universal university syllabus. It is written for a four-credit course of roughly three lecture hours plus two to three laboratory or computational hours a week across fifteen weeks, and it is deliberately more mathematical than University Physics I–IV: linear algebra and differential equations are working tools here, not background. Twenty units are mapped against a suggested fifteen-week delivery, so several units share a teaching week. Departments differ widely in how much formalism they expect at this stage; follow your institution's published scope, notation, laboratory programme, and assessment rules. A result should be checked against units, signs, limiting cases, and the conditions under which its model was derived.