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

Autori
Adam, J. ; ... ; Antičić, Tome ; ... ; Erhardt, Filip ; ... ; Gotovac, S. ; ... ; ... ; Planinić, Mirko ; ... ; Poljak, Nikola ; ... ; Simatović, Goran ; ... ; Utrobičić, Antonija ; ... ; Vicković, Linda ; ... ; Zyzak, M.

Kolaboracija
ALICE Collaboration

Izvornik
Nature physics (1745-2473) 11 (2015); 811-814

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
mass difference ; nuclei ; anti-nuclei ; ALICE ; CERN

Sažetak
The measurement of the mass differences for systems bound by the strong force has reached a very high precision with protons and anti- protons1, 2. 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 theories3, 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-), and 3He and 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 nuclei5, 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).

Izvorni jezik
Engleski

Znanstvena područja
Fizika

POVEZANOST RADA