首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
We have performed precision laser spectroscopy on individual 6He (t(1/2)=0.8 s) atoms confined and cooled in a magneto-optical trap, and measured the isotope shift between 6He and 4He to be 43 194.772+/-0.056 MHz for the 2(3)S1-3(3)P2 transition. Based on this measurement and atomic theory, the nuclear charge radius of 6He is determined for the first time in a method independent of nuclear models to be 2.054+/-0.014 fm. The result is compared with the values predicted by a number of nuclear structure calculations and tests their ability to characterize this loosely bound halo nucleus.  相似文献   

2.
The intrinsic quadrupole moment of176Lu has been determined by Coulomb excitation with α-particles to be 6.98±0.10 b. Evidence for a new level at approximately 578 keV with presumably collective structure is presented.  相似文献   

3.
The nuclear electric quadrupole moment (Q moment) of the neutron-rich nucleus 33Al (I = 5/2 , T 1/2 = 41 ms) has been measured by the $ \beta$ -ray detected nuclear quadrupole resonance ( $ \beta$ -NQR) method for the first time. The 33Al nucleus is considered to be on the border of the island of inversion within which a significant intrusion of the pf orbits occurs across the N = 20 shell gap and the intrusion causes an anomalous enhancement of the Q moment. Polarized 33Al nuclei were produced from 36S (77.5MeV/u beams through the fragmentation process and separated by LISE fragment separator at GANIL. The 33Al nuclei were implanted into a Al2O3 single-crystal plate and the $ \beta$ -NQR spectrum was successfully obtained.  相似文献   

4.
The large discrepancy between the value 0·4 D Å measured by Buckingham for the quadrupole moment of oxygen and the recent value 1·21 D Å used by Yamamoto and Cattani and by Bouanich in line-broadening calculations is examined. When hexadecapolar and repulsive interactions are included, the discrepancy in the values of the quadrupole moment obtained by the bi-refringence method and line width calculations is resolved provided a value of Φ ~ 8 D Å3 is used for the hexadecapole moment of oxygen.  相似文献   

5.
We estimate the electric quadrupole moment of theΩ ? within current non-relativistic quark models. With only one-gluon exchange as a source of tensor forces we get typically a valueQ ω=0.004 fm2 which is probably very hard to measure experimentally.  相似文献   

6.
The ground state nuclear moments of186Ir (j π=5(+)) have been determined with NMR on oriented186Ir in Ni as |μ|=3.80 ?0.02 +0.12 μ n andQ=?3.00 (15)b. The quadrupole moment is consistent with an anamolousj π K=5+0 or 5+1 ground state configuration. The explanation of the magnetic moment in terms of pure 5+0 or 5+1 configurations would require a high collectiveg R-factor ofg R≧0.76. On the other hand the magnetic moment can be explained with a “normal”g R and a mixed ground state configuration.  相似文献   

7.
8.
We report the measurement of the energies of the 4f → 3d, 3d → 2p and 2p → 1s atomic transitions in muonic 181Ta. Using transitions to and from the 1s and 2p levels, as well as the hyperfine splittings of the 2p and 3d states, we obtained the radial charge parameters assuming deformed Fermi distributions. We found the intrinsic static quadrupole moment Q0 = 6.82 ± 0.06 e · b, in excellent agreement with Coulomb excitation results. We verified that the dynamic (corresponding to transitions to the first excited state) and the static (ground state) E2 moments were equal to within 1.1 %. The intrinsic hexadecapole moment was determined to be Π0 = ?0.12 ± 0.40 e · b2.  相似文献   

9.
The quadrupole moment ratio of9Li and11Li was measured by a combination of in-beam laser induced nuclear polarization and Β-NMR in LiNbO3. The result ¦Q(11Li)/Q(9Li)¦=1.14(16) is consistent with cluster models describing11Li as composed of a9Li core and a far extended halo of two loosely bound neutrons.  相似文献   

10.
We present the Ernst potential and the line element of an exact solution of Einstein’s vacuum field equations that contains as arbitrary parameters the total mass, the angular momentum, and the quadrupole moment of a rotating mass distribution. We show that in the limiting case of slowly rotating and slightly deformed configuration, there exists a coordinate transformation that relates the exact solution with the approximate Hartle solution. It is shown that this approximate solution can be smoothly matched with an interior perfect fluid solution with physically reasonable properties. This opens the possibility of considering the quadrupole moment as an additional physical degree of freedom that could be used to search for a realistic exact solution, representing both the interior and exterior gravitational field generated by a self-gravitating axisymmetric distribution of mass of perfect fluid in stationary rotation.  相似文献   

11.
Microwave transitions between the Zeeman split doublet states 22 P 1/2 and 22 P 3/2 of7Li have been measured using the optical double resonance method. The fine structure separation was determined to bev fs=10.053.184(58) MHz. The hyperfine structure was well resolved and led to considerably improved precision of the diagonal coupling constantsa 1/2=45.914(25) MHz,a 3/2=?3.055(14) MHz,b=?0.221(29) MHz. Furthermore, the contact, spin dipolar and orbital magnetic hyperfine constants are evaluated using additional results from level crossing experiments, which are more sensitive on the non-diagonal magnetic hyperfine constanta 3/2,1/2. The results are in good agreement with recent theoretical calculations. The nuclear quadrupole moment is derived fromb to beQ(7Li)=?41(6) mbarn.  相似文献   

12.
13.
The persistent internal quadrupole moment which has been observed in Li-doped ZnO crystals is studied theoretically. The quadrupole moment is expressed in terms of relaxation coefficients and effective cross sections characterizing the scattering and capture processes of the photo carriers. Furthermore, it is related to the anisotropy of the mobility and of the persistent internal polarization.  相似文献   

14.
15.
Due to CP-invariance violation a vector particle can acquire a T- and P-odd electric dipole moment and a magnetic quadrupole one. The W-boson magnetic quadrupole moment is calculated in the Kobayashi-Maskawa model. This is the only known CP-odd moment arising in this model in two-loop approximation.  相似文献   

16.
Doug Beder 《Nuclear Physics A》1978,305(2):411-417
The quadrupole moment of the ground state of the μ+e? atom is calculated to be (3memμ)?1; effects in a crystal are briefly discussed.  相似文献   

17.
18.
19.
Yamaguchi  T.  Sato  K.  Ha  C.  Morishita  A.  Tanaka  K.  Miyake  T.  Sasaki  M.  Minamisono  K.  Akai  H.  Mihara  M.  Fukuda  M.  Matsuta  K.  Nojiri  Y.  Minamisono  T. 《Hyperfine Interactions》1999,120(1-8):689-694
The sign of the quadrupole coupling constant eqQ of 8B in ZrB2 is determined to be positive through the β-delayed α-ray anisotropy measurement combined with the spin manipulation technique by use of the β-NMR. According to the theoretical calculation of the electric field gradient in ZrB2, the sign of the quadrupole moment of 8B is deduced to be positive. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号