Precision measurement of the mass difference between light nuclei and anti-nuclei

0450498 - ÚJF 2016 RIV GB eng J - Journal Article
Adam, J. - Adamová, Dagmar - Bielčík, J. - Bielčíková, Jana - Broz, M. - Čepila, J. - Contreras, J. G. - Eyyubova, G. - Ferencei, Jozef - Křelina, M. - Křížek, Filip - Kučera, Vít - Kushpil, Svetlana - Mareš, Jiří A. - Petráček, V. - Pospíšil, Jan - Schulc, M. - Špaček, M. - Šumbera, Michal - Vajzer, Michal - Vaňát, Tomáš - Závada, Petr … Total 987 authors
Precision measurement of the mass difference between light nuclei and anti-nuclei.
Nature Physics. Roč. 11, č. 10 (2015), s. 811-814. ISSN 1745-2473. E-ISSN 1745-2481
R&D Projects: GA MŠMT(CZ) LG13031
Institutional support: RVO:68378271 ; RVO:61389005
Keywords : ALICE collaboration * spectroscopy * antihydrogen
Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders; BF - Elementary Particles and High Energy Physics (FZU-D)
Impact factor: 18.791, year: 2015

The extension of such measurement from (anti-)baryons to (anti-) nuclei allows one to probe any difference in the interactions between nucleons and anti-nucleons encoded in the (anti-) nuclei masses. This force is a remnant of the underlying strong interaction among quarks and gluons and can be described by effective theories(3), but cannot yet be directly derived from quantum chromodynamics. Here we report a measurement of the difference between the ratios of the mass and charge of deuterons (d) and anti-deuterons ((d) over bar), and He-3 and (3)(He) over bar nuclei carried out with the ALICE (A Large Ion Collider Experiment)(4) detector in Pb-Pb collisions at a centre-of-mass energy per nucleon pair of 2.76 TeV. Our direct measurement of the mass-over-charge differences confirms CPT invariance to an unprecedented precision in the sector of light nuclei(5,6). This fundamental symmetry of nature, which exchanges particles with anti-particles, implies that all physics laws are the same under the simultaneous reversal of charge(s) (charge conjugation C), reflection of spatial coordinates (parity transformation P) and time inversion (T).
Permanent Link: http://hdl.handle.net/11104/0251801