The Proton Radius Puzzle

  title={The Proton Radius Puzzle},
  author={Carl E. Carlson},
  journal={Progress in Particle and Nuclear Physics},
  • C. Carlson
  • Published 18 February 2015
  • Physics
  • Progress in Particle and Nuclear Physics

Figures from this paper

The proton radius: are we still puzzled?

The proton radius puzzle began in 2010 when the CREMA Collaboration released their measurement of the proton radius from muonic hydrogen spectroscopy: $r_{p}=0.84184(67)$ fm, This was five standard

Review of experimental and theoretical status of the proton radius puzzle

The discrepancy between the measured Lamb shift in muonic hydrogen and expectations from electron-proton scattering and regular hydrogen spectroscopy has become known as the proton radius puzzle,

Solving the Muon Mystery

A large team made up of researchers from across the globe has repeated experiments conducted several years ago that showed a different radius for a proton when it was orbited by a muon as opposed to

The proton charge radius

Nucleons (protons and neutrons) are the building blocks of atomic nuclei, and are responsible for more than 99% of the visible matter in the universe. Despite decades of efforts in studying its

The proton size

The proton charge radius has been measured since the 1950s using elastic electron–proton scattering and ordinary hydrogen atomic spectroscopy. In 2010, a highly precise measurement of the proton

The proton radius (puzzle?) and its relatives

Laser spectroscopy of muonic deuterium

The deuteron is too small, too The radius of the proton has remained a point of debate ever since the spectroscopy of muonic hydrogen indicated a large discrepancy from the previously accepted value.

The Rydberg constant and proton size from atomic hydrogen

The authors obtained the size of the proton using very accurate spectroscopic measurements of regular hydrogen using an asymmetric fit function, which eliminates line shifts from quantum interference of neighboring atomic resonances.

The Proton Radius Anomaly from the Sheltering of Unruh Radiation

The proton radius has been measured for many years to be 0.88 fm, with experiments using electron-proton scattering and by using atomic spectoscopy to look at the Lamb shift seen by an orbiting



Toward a resolution of the proton size puzzle

We show that off-mass-shell effects arising from the internal structure of the proton provide a new proton polarization mechanism in the Lamb shift, proportional to the lepton mass to the fourth

Proton radius puzzle and large extra dimensions

We propose a theoretical scenario to solve the proton radius puzzle which recently arises from the muonic hydrogen experiment. In this framework, 4 + n dimensional theory is incorporated with

Muonic Hydrogen and the Proton Radius Puzzle

The extremely precise extraction of the proton radius obtained by Pohl et al. from the measured energy difference between the 2P and 2S states of muonic hydrogen disagrees significantly with that

Proton size anomaly.

It is found that the many constraints from low energy data disfavor new spin-0, spin-1, and spin-2 particles as an explanation for the Lamb shift in muonic hydrogen.

The PRad experiment and the proton radius puzzle

New results from the recent muonic hydrogen experiments seriously questioned our knowledge of the proton charge radius, rp. The new value, with its unprecedented less than sub-percent precision, is

Some issues concerning the proton charge radius puzzle

p i 1=2 derived from electron scattering and from the Lamb shift of muonic hydrogen has caused a considerable worry in the physics community. Since the Lamb shift is a corner stone of the tests of

Studying the proton "radius" puzzle with μp elastic scattering

The disagreement between the proton radius determined from muonic hydrogen and from electronic measurements is called the proton radius puzzle. The resolution of the puzzle remains unclear and

The MUSE Experiment: Studying the Proton Radius Puzzle with muon-proton Elastic Scattering

The Proton Radius Puzzle refers to the disagreement between the proton charge radius determined from muonic hydrogen and the radius determined from atomic hydrogen level transitions and ep elastic

Proton radius puzzle and quantum gravity at the Fermi scale

We show how the “proton radius puzzle” emerging from the measurement of the Lamb shift in muonic hydrogen may be solved by means of a binding energy contribution due to an effective Yukawian