Uganka protonskega radija

V članku je predstavljeno neskladje meritev nabojnega radija protona, ki v svetu jedrske fizike zadnje desetletje odmeva pod vzdevkom “uganka protonskega radija”. Podrobneje je predstavljena meritev radija z obravnavo elastičnega sipanja elektronov na protonih in eksperiment na mikrotronu v Mainzu. V članku so predstavljeni rezultati ponovne regresije s pridobljenima radijema (0.876±0.006) fm in (0.868±0.048) fm, ki podpirata večjo vrednost radija. Sledi kratek pregled meritve Lambovih premikov in eksperimentov, ki napovedujejo razrešitev uganke ter obravnava pomena uganke za jedrsko in atomsko fiziko

Proton radius puzzle

This article deals with discrepancies between measurements of the proton charge radius which gained their reputation over the past decade under the nickname ”proton radius puzzle”. Firstly the elastic electron-proton scattering measurements are discussed with emphasis on the experiment at the Mainz Microtron. After that the results of the reanalysis of the data from Mainz are presented yielding charge radius values of (0.876 ± 0.006) fm and (0.868 ± 0.048) fm which coincide with the larger proton radius. Then, Lamb shift measurements are explained and a short overview of the latest experiments which may foreshadow the solution of the puzzle is provided. aT the end the impact of the puzzle on nuclear and atomic physics is discussed.