# XIIIth Quark Confinement and the Hadron Spectrum

July 31, 2018 to August 6, 2018
Maynooth University
Europe/Dublin timezone

## Spectroscopy of muonic atoms

Aug 5, 2018, 4:30 PM
30m
Hall B (Arts Bldg)

### Hall B

#### Arts Bldg

Invited talk E: QCD and New Physics

### Speaker

Aldo Antognini (Paul Scherrer Institute)

### Description

We have measured several 2S-2P transitions in muonic hydrogen ($\mu$p), muonic deuterium ($\mu$d) and muonic helium ions ($\mu^3$He, $\mu^4$He). From muonic hydrogen we extracted a proton charge radius 20 times more precise than obtained from electron-proton scattering and hydrogen high-precision laser spectroscopy but at a variance of $7\sigma$ from these values. This discrepancy is nowadays referred to as the proton radius puzzle''.

The status of the proton charge radius puzzle including the new insights obtained from spectroscopy of other muonic atoms will be discussed.

### Primary author

Aldo Antognini (Paul Scherrer Institute)