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11.
G. Neyens D.L. Balabanski K. Vyvey S. Ternier N. Coulier R. Coussement P.M. Walker A.P. Byrne G.D. Dracoulis P. Blaha 《Zeitschrift für Physik A Hadrons and Nuclei》1997,358(2):267-268
The method of the level mixing spectroscopy (LEMS) was applied for the first time for the study of the static quadrupole moments of high-K isomers in the A ≈ 180 mass region. Results from a preliminary experiment for the static quadrupole moment of the (750 ns) isomer in 179W give a limit for its upper value Q < 7b, corresponding to a quadrupole deformation of β2< 0.343. 相似文献
12.
D. L. Balabanski M. Ionescu-Bujor A. Iordachescu D. Bazzacco F. Brandolini D. Bucurescu S. Chmel M. Danchev M. De Poli G. Georgiev H. Haas H. Hübel N. Marginean R. Menegazzo G. Neyens P. Pavan G. Rainovski C. Rossi Alvarez C. A. Ur K. Vyvey S. Frauendorf 《The European Physical Journal A - Hadrons and Nuclei》2003,20(1):191-192
The quadrupole interaction of high-spin isomers in 193Pb implanted into solid Hg cooled at a temperature T = 170 K has been investigated by the time-differential perturbed
-ray angular-distribution method. Spectroscopic quadrupole moment values of
eb and 0.45(4) eb have been deduced for the 21/2- and 33/2 + three-neutron states, respectively. A much higher value
eb has been determined for the 29/2- isomer, the band head of a magnetic rotational band.Received: 4 November 2002, Published online: 2 March 2004PACS:
21.10.Ky Electromagnetic moments - 27.80. + w
相似文献
13.
Neyens G Kowalska M Yordanov D Blaum K Himpe P Lievens P Mallion S Neugart R Vermeulen N Utsuno Y Otsuka T 《Physical review letters》2005,94(2):022501
Unambiguous values of the spin and magnetic moment of 31Mg are obtained by combining the results of a hyperfine-structure measurement and a beta-NMR measurement, both performed with an optically polarized ion beam. With a measured nuclear g factor and spin I=1/2, the magnetic moment mu(31Mg)=-0.88355(15)mu(N) is deduced. A revised level scheme of 31Mg (Z=12, N=19) with ground state spin/parity I(pi)=1/2(+) is presented, revealing the coexistence of 1p-1h and 2p-2h intruder states below 500 keV. Advanced shell-model calculations and the Nilsson model suggest that the I(pi)=1/2(+) ground state is a strongly prolate deformed intruder state. This result plays a key role for the understanding of nuclear structure changes due to the disappearance of the N=20 shell gap in neutron-rich nuclei. 相似文献
14.
Balabanski DL Vyvey K Neyens G Coulier N Coussement R Georgiev G Lèpine-Szily A Ternier S Teughels S Mineva M Walker PM Blaha P Almehed D Frauendorf S 《Physical review letters》2001,86(4):604-607
The spectroscopic quadrupole moment of the high-spin, high- K five-quasiparticle isomer (K(pi) = 35/2(-), T(1/2) = 750(80) ns, E(i) = 3349 keV) in (179)W has been determined using the level mixing spectroscopy method. A value Q(s) = 4.00(+0.83-1.06)e b was derived, which corresponds to an intrinsic quadrupole moment Q0 = 4.73(+0.98-1.25)e b and to a quadrupole deformation beta(2) = 0.185(+0.038-0.049). These values differ significantly from the deduced ground-state quadrupole moments and are in disagreement with the current theoretical predictions in this mass region. 相似文献
15.
Yordanov DT Kowalska M Blaum K De Rydt M Flanagan KT Lievens P Neugart R Neyens G Stroke HH 《Physical review letters》2007,99(21):212501
We report on the first determination of the nuclear ground-state spin of 33Mg, I=3/2, and its magnetic moment, mu= -0.7456(5) mu(N), by combining laser spectroscopy with nuclear magnetic resonance techniques. These values are inconsistent with an earlier suggested 1 particle-1 hole configuration and provide evidence for a 2 particle-2 hole intruder ground state with negative parity. The results are in agreement with an odd-neutron occupation of the 3/2 [321] Nilsson orbital at a large prolate deformation. The discussion emphasizes the need of further theoretical and experimental investigation of the island of inversion, a region previously thought to be well understood. 相似文献
16.
T. Nagatomo K. Shimada K. Asahi D. L. Balabanski J. M. Daugas M. Depuydt M. De Rydt L. Gaudefroy S. Grévy Y. Hasama Y. Ichikawa D. Kameda P. Morel L. Perrot C. St?del J. C. Thomas W. Vanderheijden N. Vermeulen P. Vingerhoets A. Yoshimi G. Neyens H. Ueno 《The European Physical Journal A - Hadrons and Nuclei》2009,42(3):383-385
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
17.
Two types of decoupling experiments are described: decoupling of the quadrupole interaction of an isomer in a non-cubic host
and decoupling of the electron-nucleus interaction of a recoiling free atom in vacuum or gases. Both perturbation interactions
can be decoupled from the nuclear system by applying a large magnetic field. Some examples and results of both types of experiments
are given.
Dedicated to Stan Hanna on the occasion of his 70th birthday 相似文献
18.
J. Odeurs R. Coussement K. Vyvey H. Muramatsu S. Gheysen R. Callens G. Neyens I. Serdons R. N. Shakhmuratov Y. Rostovtsev O. Kocharovskaya 《Hyperfine Interactions》2002,143(1-4):97-110
A significant reduction of absorption of single gamma photons has been observed using the Mössbauer spectra of 57Fe in a FeCO3 crystal. The absorption deficit can be ascribed to partially destructive interference for absorption because of two indistinguishable absorption paths. The necessary coherence is created by means of level mixing produced by a suitable combination of a magnetic dipole and electric quadrupole interaction. 相似文献
19.
Krieger A Blaum K Bissell ML Frömmgen N Geppert Ch Hammen M Kreim K Kowalska M Krämer J Neff T Neugart R Neyens G Nörtershäuser W Novotny Ch Sánchez R Yordanov DT 《Physical review letters》2012,108(14):142501
The nuclear charge radius of (12)Be was precisely determined using the technique of collinear laser spectroscopy on the 2s(1/2)→2p(1/2,3/2) transition in the Be(+) ion. The mean square charge radius increases from (10)Be to (12)Be by δ(10,12)=0.69(5) fm(2) compared to δ(10,11)=0.49(5) fm(2) for the one-neutron halo isotope ^{11}Be. Calculations in the fermionic molecular dynamics approach show a strong sensitivity of the charge radius to the structure of ^{12}Be. The experimental charge radius is consistent with a breakdown of the N=8 shell closure. 相似文献
20.
Chevrier R Daugas JM Gaudefroy L Ichikawa Y Ueno H Hass M Haas H Cottenier S Aoi N Asahi K Balabanski DL Fukuda N Furukawa T Georgiev G Hayashi H Iijima H Inabe N Inoue T Ishihara M Ishii Y Kameda D Kubo T Nanao T Neyens G Ohnishi T Rajabali MM Suzuki K Takeda H Tsuchiya M Vermeulen N Watanabe H Yoshimi A 《Physical review letters》2012,108(16):162501
We report on the spectroscopic quadrupole moment measurement of the 7/2(1)(-) isomeric state in (16)(43)S(27) [E*=320.5(5) keV, T(1/2)=415(3) ns], using the time dependent perturbed angular distribution technique at the RIKEN RIBF facility. Our value, |Q(s)|=23(3) efm(2), is larger than that expected for a single-particle state. Shell model calculations using the modern SDPF-U interaction for this mass region reproduce remarkably well the measured |Q(s)|, and show that non-negligible correlations drive the isomeric state away from a purely spherical shape. 相似文献