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111.
The lifetime and magnetic moment of43Ti (Iπ-7/2, T1/2=0.50 sec), one of the mirror beta-radioactive nuclei in the f7/2-shell, have been measured with a fragment separator built at the Bevalac of the LBL. By means of the beta-NMR method on43Ti, a preliminary value of the magnetic moment of43Ti was determined to be μ=(0.70±0.07) μπ.  相似文献   
112.
The nuclear electric quadrupole moment of41Sc(Iπ=7/2) was experimentally determined by use of the NMR detection in which the asymmetric β-ray distribution from spin polarized nuclei was monitored. The magnetic interaction of the state with high external magnetic field and the nuclear quadrupole interaction with the electric field gradient obtained in TiO2 crystal were studied. The field gradient seen to the implanted41Sc was measured independently by the high field NMR detection on the stable isotope45Sc located in the equivalent41Sc site with. |Q(41Sc;Iπ=7/2)|=(0.120±0.006) b was determined.  相似文献   
113.
The nuclear magnetic dipole moment mu and electric quadrupole moment Q of the beta-emitting 16N(Ipi = 2(-), T(1/2) = 7.13 s) nucleus have been determined for the first time by detecting its beta-NMR in a MgO crystal and beta-NQR (nuclear quadrupole resonance) in a TiO (2) crystal to be /mu/ = (1.9859+/-0.0011) mu(N) and /Q/ = (17.9+/-1.7) mb, respectively. Although the prediction of mu given by the Hartree-Fock calculation agrees well with the experiment, an abnormally small effective charge for neutrons is required to account for the experimental Q.  相似文献   
114.
The alignment correlation term in the β-ray angular distribution from purely nuclear spin aligned 20F has been measured to test the G-parity conservation law which is one of the fundamental symmetries in the weak nucleon current. We utilized the hyperfine interaction of 20F in an MgF2 single crystal and successfully created the pure alignment from the polarization by means of the spin manipulation technique based on the β-NMR method.  相似文献   
115.
The magnetic moment of short lived β-emitter 24mAl (426 keV, I π ?=?1?+?, T 1/2?=?131 ms) has been measured by means of β-NMR technique, for the first time. From the β-NMR spectrum, the magnetic moment was determined as $\left| {\upmu}\left( ^{\rm 24m}{\rm Al} \right) \right|=\left( {2.99\pm 0.09} \right){\upmu}_{\rm N}$ . Combined with the known magnetic moment of the mirror partner 24mNa, the expectation value of <?S z?> is obtained to be (0.08 ± 0.12). These values are reproduced well by the shell model calculation.  相似文献   
116.
We measured the polarization of the $\upbeta $ -emitting 23Ne (I π ?= 5/2?+?, T 1/2?= 37.24 s) and 25Al(I π ?= 5/2?+?, T 1/2?= 7.18 s) produced through the one nucleon pickup reactions and 24mAl(I π ?= 1?+?, T 1/2?= 131 ms, E ex?= 426 keV) and 28P(I π ?= 3?+?, T 1/2?= 270 ms) produced through charge-exchange reactions in the intermediate energy heavy ion collisions. We compared them with those from the projectile fragmentation process. The larger polarization seems to persistently be positive throughout the momentum distribution, and sharper momentum distributions suggest that nuclear friction mechanism is responsible for the polarization phenomena.  相似文献   
117.
Sato  K.  Miyake  T.  Morishita  A.  Matsuta  K.  Minamisono  T.  Tanigaki  M.  Takeda  S.  Mihara  M.  Fukuda  M.  Nojiri  Y.  Minamisono  K.  Fukao  T.  Matsumoto  Y.  Ohtsubo  T.  Fukuda  S.  Momota  S.  Yoshida  K.  Ozawa  A.  Kobayashi  T.  Tanihata  I.  Sagawa  H.  Kitagawa  H.  Krebs  Gray F.  Alonso  Jose R.  Symons  T. James M. 《Hyperfine Interactions》1999,120(1-8):661-665
The electric quadrupole interaction of 19O(Iπ=(5/2)+, T1/2=27.0 s) in TiO2 single crystal was studied in detail by means of the β-NQR to determine the electric quadrupole moments Q of short-lived β-emitting nuclei 19O and 13O(Iπ=(3/2)-, T1/2=8.6 ms). Two implantation sites were found for the implanted O nucleus and the quadrupole coupling constants of 19O at these sites were determined. We observed FT-NMR of the enriched stable isotope 17O in TiO2 and obtained the electric field gradient (EFG) at the oxygen substitutional site. With this knowledge, we have determined Q(13O)=11.0 ± 1.3 mb and Q(19O)=3.7 ± 0.4 mb. The present results are compared with the theoretical values calculated by the shell model code, OXBASH and by the Hartree–Fock calculation with the realistic potential. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
118.
Sato  K.  Akai  H.  Maruyama  Y.  Minamisono  T.  Matsuta  K.  Fukuda  M.  Mihara  M. 《Hyperfine Interactions》1999,120(1-8):145-149
We present ab initio calculations of electric field gradients (EFGs) at impurity sites in ionic crystals TiO2, Al2O3 and CaCO3. The electronic structure was calculated self-consistently by the KKR method in the framework of the local spin density approximation of the density functional theory. The system with a single impurity was simulated by the super cell method. It was found that EFGs for the transition metal impurities (Sc, Nb, Cd and Ta) in TiO2 were well reproduced by the calculations if the charge state of them in TiO2 was taken into account. The present method was applied to the determination of the implantation sites of N and O nuclei in TiO2. The calculation of EFGs at a Si impurity in Al2O3 and at Ca site in CaCO3 were used to derive the quadrupole moments of 27Si and 39Ca from their quadrupole coupling constants. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
119.
Matsuta  K.  Minamisono  T.  Tanigaki  M.  Onishi  T.  Fukuda  M.  Mihara  M.  Akai  H.  Sasaki  M.  Yamaguchi  T.  Miyake  T.  Sato  K.  Minamisono  K.  Ha  C.  Tanaka  K.  Kidera  K.  Morishita  A.  Kaminaka  S.  Tsubota  T.  Sumikama  T.  Kitagawa  A.  Torikoshi  M.  Kanazawa  M.  Nishio  T.  Koda  S.  Ohtsubo  T.  Nojiri  Y.  Momota  S.  Hanna  S.S.  Alonso  J.R.  Krebs  G.F.  Symons  T.J.M. 《Hyperfine Interactions》1999,120(1-8):719-723
The Knight shifts K for short-lived β emitters 12N and 27Si implanted in Pt have been measured by means of β-NMR technique. The results were K(12N in Pt)= +(5.8 ± 2.1)× 10-4 and K(27Si in Pt)= +(1.4 ± 0.8)× 10-3. The spin–lattice relaxation time T1 was measured for 12N in Pt. The result was T1(12N in Pt, T=300 K)= 66 ± 8 ms, thus, T1T= 20 ± 2 Ks. The present Knight shifts are in good agreement with the KKR band structure calculation with local lattice relaxation determined theoretically. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
120.
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