Laser spectroscopy of muonic deuterium

Pohl, Randolf, Nez, Francois, Fernandes, Luis M. P., Amaro, Fernando D., Biraben, Francois, Cardoso, Joao M. R., Covita, Daniel S., Dax, Andreas, Dhawan, Satish, Diepold, Marc, Giesen, Adolf, Gouvea, Andrea L., Graf, Thomas, Hänsch, Theodor W., Indelicato, Paul, Julien, Lucile, Knowles, Paul, Kottmann, Franz, Le Bigot, Eric-Olivier, Liu, Yi-Wei, Lopes, Jose A. M., Ludhova, Livia, Monteiro, Cristina M. B., Mulhauser, Francoise, Nebel, Tobias, Rabinowitz, Paul, dos Santos, Joaquim M. F., Schaller, Lukas A., Schuhmann, Karsten, Schwob, Catherine, Taqqu, David, Veloso, Joao F. C. A. and Antognini, Aldo (2016): Laser spectroscopy of muonic deuterium. In: Science, Vol. 353, No. 6300: pp. 669-673

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 r(d) and the polarizability serve as important benchmarks for understanding the nuclear forces and structure. Muonic deuterium mu d is the exotic atom formed by a deuteron and a negative muon mu-. We measured three 2S-2P transitions in md and obtain r(d) = 2.12562(78) fm, which is 2.7 times more accurate but 7.5 sigma smaller than the CODATA-2010 value r(d) = 2.1424(21) fm. The md value is also 3.5 sigma smaller than the rd value from electronic deuterium spectroscopy. The smaller rd, 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.

• Item Type: Journal article
• Faculties: Physics
• Subjects: 500 Science > 530 Physics
• ISSN: 0036-8075
• Language: English