| Literature DB >> 27516595 |
Randolf Pohl1, François Nez2, Luis M P Fernandes3, Fernando D Amaro3, François Biraben2, João M R Cardoso3, Daniel S Covita4, Andreas Dax5, Satish Dhawan5, Marc Diepold6, Adolf Giesen7, Andrea L Gouvea3, Thomas Graf8, Theodor W Hänsch9, Paul Indelicato2, Lucile Julien2, Paul Knowles10, Franz Kottmann11, Eric-Olivier Le Bigot2, Yi-Wei Liu12, José A M Lopes13, Livia Ludhova10, Cristina M B Monteiro3, Françoise Mulhauser14, Tobias Nebel6, Paul Rabinowitz15, Joaquim M F dos Santos3, Lukas A Schaller10, Karsten Schuhmann16, Catherine Schwob2, David Taqqu17, João F C A Veloso4, Aldo Antognini18.
Abstract
The deuteron is the simplest compound nucleus, composed of one proton and one neutron. Deuteron properties such as the root-mean-square charge radius rd and the polarizability serve as important benchmarks for understanding the nuclear forces and structure. Muonic deuterium μd is the exotic atom formed by a deuteron and a negative muon μ(-). We measured three 2S-2P transitions in μd and obtain r(d) = 2.12562(78) fm, which is 2.7 times more accurate but 7.5σ smaller than the CODATA-2010 value r(d) = 2.1424(21) fm. The μd value is also 3.5σ smaller than the r(d) value from electronic deuterium spectroscopy. The smaller r(d), when combined with the electronic isotope shift, yields a "small" proton radius r(p), similar to the one from muonic hydrogen, amplifying the proton radius puzzle.Entities:
Year: 2016 PMID： 27516595 DOI： 10.1126/science.aaf2468
Source DB: PubMed Journal: Science ISSN： 0036-8075 Impact factor: 47.728