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61.
62.
F. de Oliveira Santos P. Himpe M. Lewitowicz I. Stefan N. Smirnova N. L. Achouri J. C. Angélique C. Angulo L. Axelsson D. Baiborodin F. Becker M. Bellegui E. Berthoumieux B. Blank C. Borcea A. Cassimi J. M. Daugas G. de France F. Dembinski C. E. Demonchy Z. Dlouhy P. Dolégiéviez C. Donzaud G. Georgiev L. Giot S. Grévy D. Guillemaud Mueller V. Lapoux E. Liénard M. J. Lopez Jimenez K. Markenroth I. Matea W. Mittig F. Negoita G. Neyens N. Orr F. Pougheon P. Roussel Chomaz M. G. Saint Laurent F. Sarazin H. Savajols M. Sawicka O. Sorlin M. Stanoiu C. Stodel G. Thiamova D. Verney A. C. C. Villari 《The European Physical Journal A - Hadrons and Nuclei》2005,24(2):237-247
The excitation function for the elastic-scattering reaction p( 18Ne, p) 18Ne was measured with the first radioactive beam from the SPIRAL facility at the GANIL laboratory and with a solid cryogenic hydrogen target. Several broad resonances have been observed, corresponding to new excited states in the unbound nucleus 19Na. In addition, two-proton emission events have been identified and are discussed. 相似文献
63.
O. Volkova E. Goodilin A. Vasiliev D. Khomskii N. Tristan P. Kerschl Yu. Skourski K. -H. Mueller B. Buechner 《JETP Letters》2005,82(10):642-645
The ferrimagnetic compounds Ca(CuxMn3?x)Mn4O12 of the double distorted perovskites AC3B4O12 family exhibit a rapid increase of the ferromagnetic component in magnetization at partial substitution of square coordinated (Mn3+)C for (Cu2+)C. In the transport properties, this is seen as a change of the semiconducting type of resistivity for the metallic one. The evolution of magnetic properties of Ca(CuxMn3?x)Mn4O12 is driven by strong antiferromagnetic exchange interaction of (Cu2+)C with (Mn3+/Mn4+)B coordinated octahedra. The competing interactions of (Mn3+)C with (Mn3+/Mn4+)B lead to the formation of noncollinear magnetic structures that can be aligned by magnetic fields. 相似文献
64.
Gade A Bazin D Brown BA Campbell CM Church JA Dinca DC Enders J Glasmacher T Hansen PG Hu Z Kemper KW Mueller WF Olliver H Perry BC Riley LA Roeder BT Sherrill BM Terry JR Tostevin JA Yurkewicz KL 《Physical review letters》2004,93(4):042501
The 9Be(32Ar, 31Ar)X reaction, leading to the 5/2+ ground state of a nucleus at the proton drip line, has a cross section of 10.4(13) mb at a beam energy of 65.1 MeV/nucleon. This translates into a spectroscopic factor that is only 24(3)% of that predicted by the many-body shell-model theory. We introduce refinements to the eikonal reaction theory used to extract the spectroscopic factor to clarify that this very strong reduction represents an effect of nuclear structure. We suggest that it reflects correlation effects linked to the high neutron separation energy (22.0 MeV) for this state. 相似文献
65.
Asner DM Dytman SA Mehrabyan S Mueller JA Nam S Savinov V Huang GS Miller DH Pavlunin V Sanghi B Shibata EI Shipsey IP Adams GS Chasse M Cummings JP Danko I Napolitano J Cronin-Hennessy D Park CS Park W Thayer JB Thorndike EH Coan TE Gao YS Liu F Stroynowski R Artuso M Boulahouache C Blusk S Butt J Dambasuren E Dorjkhaidav O Haynes J Menaa N Mountain R Muramatsu H Nandakumar R Redjimi R Sia R Skwarnicki T Stone S Wang JC Zhang K Mahmood AH Csorna SE Bonvicini G Cinabro D Dubrovin M Bornheim A 《Physical review letters》2004,92(14):142001
We report on the observation of the eta(')(c)(2(1)S0), the radial excitation of the eta(c)(1(1)S0) ground state of charmonium, in the two-photon fusion reaction gammagamma-->eta(')(c)-->K(0)(S)K+/-pi(-/+) in 13.6 fb(-1) of CLEO II/II.V data and 13.1 fb(-1) of CLEO III data. We obtain M(eta(')(c))=3642.9+/-3.1(stat)+/-1.5(syst) MeV and M(eta(c))=2981.8+/-1.3(stat)+/-1.5(syst) MeV. The corresponding values of hyperfine splittings between 1S0 and 3S1 states are DeltaM(hf)(1S)=115.1+/-2.0 MeV and DeltaM(hf)(2S)=43.1+/-3.4 MeV. Assuming that the eta(c) and eta(')(c) have equal branching fractions to K(S)Kpi, we obtain Gamma(gammagamma)(eta(')(c))=1.3+/-0.6 keV. 相似文献
66.
Van Roosbroeck J Guénaut C Audi G Beck D Blaum K Bollen G Cederkall J Delahaye P De Maesschalck A De Witte H Fedorov D Fedoseyev VN Franchoo S Fynbo HO Górska M Herfurth F Heyde K Huyse M Kellerbauer A Kluge HJ Köster U Kruglov K Lunney D Mishin VI Mueller WF Nagy S Schwarz S Schweikhard L Smirnova NA Van de Vel K Van Duppen P Van Dyck A Walters WB Weissman L Yazidjian C 《Physical review letters》2004,92(11):112501
Using resonant laser ionization, beta-decay studies, and for the first time mass measurements, three beta-decaying states have been unambiguously identified in 70Cu. A mass excess of -62 976.1(1.6) keV and a half-life of 44.5(2) s for the (6-) ground state have been determined. The level energies of the (3-) isomer at 101.1(3) keV with T(1/2)=33(2) s and the 1+ isomer at 242.4(3) keV with T(1/2)=6.6(2) s are confirmed by high-precision mass measurements. The low-lying levels of 70Cu populated in the decay of 70Ni and in transfer reactions compare well with large-scale shell-model calculations, and the wave functions appear to be dominated by one proton-one neutron configurations outside the closed Z=28 shell and N=40 subshell. This does not apply to the 1+ state at 1980 keV which exhibits a particular feeding and deexcitation pattern not reproduced by the shell-model calculations. 相似文献
67.
Parity-violating electron deuteron scattering and the proton's neutral weak axial vector form factor
Ito TM Averett T Barkhuff D Batigne G Beck DH Beise EJ Blake A Breuer H Carr R Clasie B Covrig S Danagoulian A Dodson G Dow K Dutta D Farkhondeh M Filippone BW Franklin W Furget C Gao H Gao J Gustafsson K Hannelius L Hasty R Hawthorne-Allen AM Herda MC Jones CE King P Korsch W Kowalski S Kox S Kramer K Lee P Liu J Martin JW McKeown RD Mueller B Pitt ML Plaster B Quéméner G Réal JS Ritter J Roche J Savu V Schiavilla R Seely J Spayde D Suleiman R Taylor S Tieulent R Tipton B Tsentalovich E 《Physical review letters》2004,92(10):102003
We report on a new measurement of the parity-violating asymmetry in quasielastic electron scattering from the deuteron at backward angles at Q2=0.038 (GeV/c)2. This quantity provides a determination of the neutral weak axial vector form factor of the nucleon, which can potentially receive large electroweak corrections. The measured asymmetry A=-3.51+/-0.57 (stat)+/-0.58 (syst) ppm is consistent with theoretical predictions. We also report on updated results of the previous experiment at Q2=0.091 (GeV/c)2, which are also consistent with theoretical predictions. 相似文献
68.
69.
Liang JF Shapira D Gross CJ Beene JR Bierman JD Galindo-Uribarri A Gomez del Campo J Hausladen PA Larochelle Y Loveland W Mueller PE Peterson D Radford DC Stracener DW Varner RL 《Physical review letters》2003,91(15):152701
Evaporation residue cross sections have been measured with neutron-rich radioactive 132Sn beams on 64Ni in the vicinity of the Coulomb barrier. The average beam intensity was 2 x 10(4) particles per second and the smallest cross section measured was less than 5 mb. Large sub-barrier fusion enhancement was observed. Coupled-channel calculations taking into account inelastic excitation significantly underpredict the measured cross sections below the barrier. The presence of several neutron transfer channels with large positive Q values suggests that multinucleon transfer may play an important role in enhancing the fusion of 132Sn and 64Ni. 相似文献
70.