Neutron-antineutron(n−n)oscillations in the deuteron are considered.Specifically,the deuteron lifetime is calculated in terms of the free-space n−n oscillation time τn−n based on NN and NN interactions derived within...Neutron-antineutron(n−n)oscillations in the deuteron are considered.Specifically,the deuteron lifetime is calculated in terms of the free-space n−n oscillation time τn−n based on NN and NN interactions derived within chiral effective field theory(EFT).This results in(2.6±0.1)×10^22τ2^n−n s,which is close to the value obtained by Dover and collaborators more than three decades ago,but disagrees with recent EFT calculations that were performed within the perturbative scheme proposed by Kaplan,Savage,and Wise.Possible reasons for the difference are discussed.展开更多
The renormalization of the iterated onepion exchange(OPE)has been studied in chiral effective field theory(χEFT)for the antinucleon-nucleon(NN)scattering in some partial waves(Phys.Rev.C 105,054005(2022)).In this pap...The renormalization of the iterated onepion exchange(OPE)has been studied in chiral effective field theory(χEFT)for the antinucleon-nucleon(NN)scattering in some partial waves(Phys.Rev.C 105,054005(2022)).In this paper,we go further for the other higher partial waves but with total angular momenta J≤3.Contact interactions are represented by a complex spherical well in the coordinate space.Changing the radius of the spherical well means changing the cutoff.We check the cutoff dependence of the phase shifts,inelasticities,and mixing angles for the partial waves and show that contact interactions are needed at leading order in channels where the singular tensor potentials of OPE are attractive.The results are compared with the energy-dependent partial-wave analysis of NN scattering data.Comparisons between our conclusions and applications of χEFT to the nucleon-nuc-leon system are also discussed.展开更多
基金supported in part by the DFG and the NSFC through funds provided to the Sino-German CRC 110"Symmetries and the Emergence of Structure in QCD"(DFG grant.no.TRR 110)the VolkswagenStiftung(93562)supported in part by The Chinese Academy of Sciences(CAS)President’s International Fellowship Initiative(PIFI)(2018DM0034)
文摘Neutron-antineutron(n−n)oscillations in the deuteron are considered.Specifically,the deuteron lifetime is calculated in terms of the free-space n−n oscillation time τn−n based on NN and NN interactions derived within chiral effective field theory(EFT).This results in(2.6±0.1)×10^22τ2^n−n s,which is close to the value obtained by Dover and collaborators more than three decades ago,but disagrees with recent EFT calculations that were performed within the perturbative scheme proposed by Kaplan,Savage,and Wise.Possible reasons for the difference are discussed.
基金Supported by the Doctoral Fund Project of Nanfang College,Guangzhou(2020BQ03)。
文摘The renormalization of the iterated onepion exchange(OPE)has been studied in chiral effective field theory(χEFT)for the antinucleon-nucleon(NN)scattering in some partial waves(Phys.Rev.C 105,054005(2022)).In this paper,we go further for the other higher partial waves but with total angular momenta J≤3.Contact interactions are represented by a complex spherical well in the coordinate space.Changing the radius of the spherical well means changing the cutoff.We check the cutoff dependence of the phase shifts,inelasticities,and mixing angles for the partial waves and show that contact interactions are needed at leading order in channels where the singular tensor potentials of OPE are attractive.The results are compared with the energy-dependent partial-wave analysis of NN scattering data.Comparisons between our conclusions and applications of χEFT to the nucleon-nuc-leon system are also discussed.