共查询到20条相似文献,搜索用时 78 毫秒
1.
Dr. W. Henning 《Zeitschrift für Physik A Hadrons and Nuclei》1968,217(5):438-456
Isomer shifts ofγ rays from rotational bands of deformed nuclei have been determined in Mössbauer effect measurements. The following changes of the mean square nuclear charge radii have been deduced:Δ〈r 2〉(156Gd, 89keV)=(+2.6±0.8)·l0?3fm2,Δ〈r 2〉(170Yb, 84keV)=(+1.2±0.3)·10?3fm2,Δ〈r 2〉(171Yb, 67keV)=(+1.1±0.2)·10?3fm2. The results are compared with theoretical calculations and additional experimental data, to study the effect of the Coriolis and centrifugal forces in rotational excitation on the motion of the nucleons. 相似文献
2.
F. E. Wagner D. Kucheida U. Zahn G. Kaindl 《Zeitschrift für Physik A Hadrons and Nuclei》1974,266(3):223-232
From Mössbauer spectra of the 36.2keV and 69.5keV gamma rays of189Os, isomer shifts and electric quadrupole interactions for a number of chemical compounds of osmium in the oxidation states +8, +6, +4, +3, and +2 were obtained. The results show that the dependence of the isomer shifts on the oxidation state of Os follows the general pattern established for other transition elements like Ru and Ir. A comparison of the isomer shift data with electron densities at the Os nuclei resulting from relativistic self-consistentfield calculations for free Os ions yieldsΔ 〈r2〉 [36 keV]=?2.0 · 10?3 fm2 andΔ 〈r2〉 [69 keV]=?0.13 · 10?3 fm3 for the changes of the mean-square nuclear charge radius of189Os. These values are in qualitative agreement with an interpretation of the low-energy level scheme of189Os in terms of two rotational bands. 相似文献
3.
W. Potzel F. E. Wagner R. L. Mössbauer G. Kaindl H. E. Seltzer 《Zeitschrift für Physik A Hadrons and Nuclei》1971,241(2):179-187
The recoilless nuclear gamma resonance of the 127 keV γ-rays of101Ru was observed in ruthenium metal, RuO2 and [Ru(NH3)4(HSO3)2]. By comparison of the isomer shifts observed in these materials for the 127 keV absorption line with the corresponding shifts of the 90keV γ-rays of99Ru one obtains δ〈r 2〉 [127 keV]/ δ〈r 2〉 [90 keV]=1.78±0.26 for the ratio of the changes of the mean square nuclear charge radii between the first excited and the ground states in these nuclei. An estimate of electron density differences based on free-ion relativistic self-consistent field calculations yields δ〈r 2〉[90keV]≈+1.4·10?3 for99Ru and δ〈r 2〉/〈r 2〉 [127 keV]≈+2.4·10?3 for the101Ru case. These results are discussed in terms of the core excitation model. 相似文献
4.
Dorothee Walcher 《Zeitschrift für Physik A Hadrons and Nuclei》1971,246(2):123-150
Using the Mössbauer technique the magnetic hyperfine splitting of the 130 keV transition in195Pt has been observed in a Pt-Fe alloy. The derived magnetic moment is μ130=(0.81 ?0.25 +0.13 μ k . Isomershift measurements with the 130 keV and the 99 keV transitions in alloys yielded Δ〈r 2〉130/Δ〈r 2〉99=1.5±0.2 for the ratio of the changes in the mean square charge radius of the two excited states. From isomershifts of the 99 keV transition in compounds an estimate of Δ〈r 2〉99/〈r 2〉=?(1.6 ?0.9 +4.4 ) · 10?4 is made for the change in radius of the first excited state. The linewidth of the Mössbauer spectrum of the 32.2 keV transition in201Hg gives a lower limit of 0.1 ns for the half-life of the second excited state. The results are compared with values for other nuclides in this mass region. 相似文献
5.
P. Heinecke 《Zeitschrift für Physik A Hadrons and Nuclei》1971,245(5):411-424
The isotope shift of the stable151Eu,153Eu, and the radioactive152Eu,154Eu isotopes and the hyperfine splitting of the152Eu isotope was investigated using a digital recording Fabry-Perot-spectrometer. From isotope shift measurements on the line λ 5 765 Å (4f 7 6s 6p z6P7/2-4f 7 6s2 a8S7/2) the relative isotope shift was derived:151Eu:0;152Eu: 0.923(8);153Eu: 1;154Eu: 1.197(8). The results show that there is a strong increase in the change of the mean square nuclear charge radius δ〈r2〉 when only one neutron is added to the 88 neutrons of the151Eu nucleus, whereas the change of δ〈r2〉 between152Eu and153Eu is of the same order of magnitude as that between153Eu and154Eu. From the hyperfine splitting of the radioactive isotope152Eu in the line δ 6865 Å (4f 7 6s 6p z 10 P 9/2-4f 7 6s2 a8S7/2) the sign of the magnetic dipole moment μI(152Eu) was found to be negative, and with this result and earlier experimental data the signs of the nuclear quadrupole momentsQ(152Eu) andQ (154Eu) could be determined to be positive. 相似文献
6.
G. Crecelius 《Zeitschrift für Physik A Hadrons and Nuclei》1972,256(2):155-175
Using the Mössbauer effect, the ratios of theg factors and the hyperfine splitting constants for the 21.6 keV state and the ground state in151Eu and of the 103 keV state and the ground state in153Eu have been measured. From these results values for the hyperfine anomaly of0Δ 151 22 =?0.81(8)% and0Δ 153 103 =+ 1.8(8)% have been derived for151Eu and153Eu, respectively. 相似文献
7.
R. Baldini-Celio M. Bozzo G. Capon R. Del Fabbro M. Grilli E. Iarocci M. Locci C. Mencuccuni G.P. Murtas M.A. Spano M. Spinetti V. Valente C. Bacci G. Penso B. Stella 《Physics letters. [Part B]》1975,58(4):471-474
The reactions e+e?→ hadrons and e+e+e?→e+e? have been studied at the J/gY (3100) resonance). The relative weights of the topological cross sections for fixed charged multiplicity are σ2=(32±5)%, σ4=(49±8)%, σ6=(18±3)%, and σ8=(1±0.6)%. The average pion multiplicities are 〈nch〉=3.8±0.3 and 〈nπo〉=3.1±0.8. The decay widths are Γe=(4.6±0.8) keV, Γh=(59±24) keV, and Γ=(68±26) keV. 相似文献
8.
Dr. H. Bokemeyer Dr. K. Wohlfahrt E. Kankeleit D. Eckardt 《Zeitschrift für Physik A Hadrons and Nuclei》1975,274(4):305-318
The Mössbauer Conversion (MBC) Spectroscopy and criteria for its useful application are discussed and compared with other MB-techniques. By help of the MBC spectroscopy the isomer shift of the first excited state in182W was measured and a change in radius ?0.05 · 10?4>Δ 〈r 2〉/〈r 2〉>?0.28 · 10?4 derived. The ratio of quadrupole moments of first excited states in180W and182W turns out to be180 Q/182 Q=0.976 (30). Due to the excellent statistical quality of the spectra the interference parameter of the 100keVE2 transition in182W could be determined to 2β=0.0165(9) for theL-shell. The MB-effect for the 61 keV transition in the instable145Pm has been detected for the first time. A widthΛ exp=2.15(58) mm/s was obtained. 相似文献
9.
Changes of the radioactive decay rate of71Ge (T 1/2=11.43 days) have been studied experimentally for71Ge in some compounds of bivalent and quadrivalent germanium. Relative changes Δλ/λ of the electron capture probability have been measured, and the chemical changes Δρ(0) of the electron density at the germanium nuclei have been determined from these measurements. Values for the Mössbauer isomer shift calibration constants for the 67 keV γ-transition of73Ge have been estimated:C=δ/Δρ(0)=(0.061±0.020) mm·s?1/a.u., Δ〈r 2〉=(21±7)·10?3 fm2, ΔR/R=(6.9±2.3)·10?4. 相似文献
10.
《Nuclear Physics A》1986,456(3):373-396
Three new methods are applied to the problem of extracting the deuteron rms matter radius from the experimental ratio of (e, d) to (e, p) scattering. A new value rEd = 1.953 (3) fm is obtained. The asymptotic method also yields 〈r4〉 = 54.5 ± 0.3 fm4 and 〈r6〉 = 1914 ± 20 fm6. Potential models of the deuteron are apparently unable to explain this rEd simultaneously with the low energy effective-range parameters of the neutron-proton system. 相似文献
11.
G. D. Alkhazov A. E. Barzakh V. P. Denisov V. S. Ivanov I. Ya. Chubukov V. S. Letokhov V. I. Mishin S. K. Sekatsky V. N. Fedoseyev 《Zeitschrift für Physik A Hadrons and Nuclei》1990,337(4):367-370
Optical isotope shifts and hyperfine structures of the147–153,155,157,159 Tb isotopes have been measured by the resonance ionization spectroscopy method. Nuclear moments and changes in nuclear charge radiiΔ 〈r 2〉 have been deduced. The “jump” inΔ 〈r 2〉 atN=88–90 has been revealed. It is compared with the relevant data for nuclei with other proton numbers. 相似文献
12.
A.R. de L. Musgrove B.J. Allen J.W. Boldeman D.M.H. Chan R.L. Macklin 《Nuclear Physics A》1976,259(3):365-377
The neutron capture cross section of 40Ca has been measured with ≈ 0.2 % energy resolution below En = 300 keV. Resonance parameters have been extracted for many new p- and d-wave resonances. Gamma-ray spectra were also measured following capture in one doublet and two resolved resonances below 50 keV. Strong feeding of low-lying p-wave levels was observed in all cases. Calculations showed that valence transitions were inadequate to account for the observed dominance of these transitions and a further mechanism is required. The average resonance parameters obtained from the data are as follows: 〈D〉 = 37 + 4keV, 104S1 = 0.16 ± 0.05, 104S2 = 2.0 ± 0.7. The average radiative widths and standard deviations of their distributions were found to be strongly l-dependent as follows: 〈Γγ〉s = 1.5 ± 0.9 eV, 〈Γγ〉p = 0.36 ± 0.09 eV and 〈Γγ〉d = 0.7 ± 0.4 eV. 相似文献
13.
G. Kaindl 《Zeitschrift für Physik A Hadrons and Nuclei》1970,240(2):100-122
The magnetic hyperfine splitting of the 72.5 keV γ rays of145Nd was investigated in intermetallic compounds of Nd and in the paramagnetic salts Nd x Y 1-x Cl3·6H2O (withx=0.02 andx=0.05) at 4.2 K. With the magnetic hyperfine tensorA of Nd0.01Y0.99Cl3·6H2O known from EPR spectroscopy, the analysis of the unresolved magnetic hyperfine spectra yieldsI e =5/2 for the spin of the 72.5 keV state, in contradiction to a previous result. The multipolarity of the 72.5 keV γ transition was found to be essentiallyM1 with δ2=0.010±0.014, and the magnetic moment of the 72.5 keV state was determined as μ(5/2)=?0.319±0.004 nm. For various divalent and trivalent Nd compounds as well as for metallic Nd the isomer shift IS of the 72.5 keV γ line was measured. A value for the change of the mean square nuclear charge radius during the 72.5 keV γ transition of Δ〈r 2〉=+(1.9±0.9)·10?3fm2 was deduced using electron density differences from free-ion Hartree-Fock calculations. 相似文献
14.
R. Yanovsky E.R. Bauminger D. Levron I. Nowik S. Ofer 《Solid State Communications》1975,17(12):1511-1514
Mössbauer studies of the 84.3 keV gamma ray of Yb170 emitted from Yb in TmxHo1?xFe2 at various temperatures were performed. These yield the crystalline field parameters (A4〈r4〉 = 36 ± 5 K, A6〈r6〉 = -3 ± 2K, the exchange field (μBHexch = 116 ± 4 K) and the Yb3+ free ion hyperfine constants (H4f = 4100 ± 150 kOe, eqQ = 2400 ± 250 MHz and H (conduction electrons) = 350±100 kOe). Spin relaxation phenomena observed in TmFe2 at low temperatures give a value of ~ 0.03 for |?(EF)Jsf|. Spectra observed in Tm0.2Ho0.8Fe2 in the spin reorientation transition region indicate that the transition is of second order. 相似文献
15.
S. Antman H. Pettersson Z. Zehlev I. Adam 《Zeitschrift für Physik A Hadrons and Nuclei》1970,237(4):285-291
The internal conversion subshell intensities of the (21.529±0.014) keV transition in151Eu and the (22.494±0.011) keV transition in149Sm have been determined in a high resolution investigation using a double-focussing iron-core spectrometer. The subshell ratios yielded unambiguousM1+E2 multipole mixtures for both transitions. δ2(E2/M1) for the 21.53 keV transition was determined to be (8.8±0.7)·10?4 and for the 22.49 keV transition to be (5.5±1.2)·10?3. 相似文献
16.
T. von Egidy W. Kaiser W. Mampe C. Hillenbrand W. Stöffl R. G. Lanier K. Mühlbauer O. W. B. Schult H. R. Koch H. A. Baader R. L. Mlekodaj R. K. Sheline E. B. Shera J. Ungrin P. T. Prokofjev L. I. Simonova M. K. Balodis H. Seyfarth B. Kardon W. Delang P. Göttel D. Breitig W. R. Kane R. F. Casten H. J. Scheerer P. Glässl E. Huenges M. Löffler H. Rösler H. K. Vonach 《Zeitschrift für Physik A Hadrons and Nuclei》1978,286(4):341-380
The transitional nucleus152Eu has been studied using the (n, e), (n, γ), (n res,γ), (n, γγ), (d, p), (d, t) and (p, d) reactions. The experiments have been performed at nine different laboratories. A model independent level scheme was established including 95 levels below 510 keV and nearly 900 transitions by combination of low energy transitions and reaction data. More than 20 additional levels result from gamma rays and/or charged particle reactions. The level scheme is interpreted in terms of the Nilsson model indicating that152Eu is a deformed nucleus. Seven rotational bands and Nilsson configurations are established. An additional 27 rotational bands are tentatively or speculatively assugned. Gallagher-Moszkowski splittings are discussed. The neutron binding energy was determined as 6305.2±0.5 keV. The energy of the 9.3 h 0? isomer is 45.599 keV. The lifetimes of four levels were measured. Nuclear Reactions151Eu(n,γ),E n =thermal and resonance; measuredE γ ,I γ ,E c.e.,I c.e.,γγ Coinc.,γγΔt coinc.;151Eu(d, p),E=12MeV and 14MeV;153Eu(d, t),E=12MeV;153Eu(p, d),E =18MeV; deduced level scheme of152Eu,J, π, T 1/2,cc, Nilsson configurations. Magnetic electron spectrometer, curved crystal spectrometer, Ge(Li) and Si(Li) detectors, magnetic spectrographs. Enriched targets. 相似文献
17.
Dr. Heinz Prange 《Zeitschrift für Physik A Hadrons and Nuclei》1968,212(5):415-434
Using the Mössbauer technique electric hyperfine interactions of the first excited non-rotational states at 64 keV in157Gd and at 86.5 keV in155Gd have been determined in GdF3 and GdCl3· 6H2O. For the ratio of quadrupolmoments the ratiosQ 64 157 /Q g 157 =1.74±0.04,Q 86.5 155 /Q g 157 =?0.07 ± 0.21 andQ g 155 /Q g 157 =0.78 ± 0.06 were found. In addition isomer shifts were observed from which a ratio δ〈r2〉 64 157 /δ〈r2〉 86.5 155 =?2.6±0.15 can be inferred. 相似文献
18.
T. F. Hoang 《Zeitschrift fur Physik C Particles and Fields》1997,73(1):149-152
The charged multiplicity distribution of hadronic decays of Z 0 from LEP and those of inclusive $e^{+}+e^{-}?ghtarrow h{?erline h} at E_{? cm}=14 {? to} 60 {? GeV}$ at E cm = 14 to 61 GeV are analyzed using a Poisson-type distribution for photon statistics, due to Scully-Lamb. Its two parameters are expressed in terms of 〈n〉 and f 2 = 〈n(n ? 1)〉 ? 〈n〉2 of the data in order to perform no-free-parameter fits. It is found that f2 behaves like $E_{? cm}^{a}$ with a = 2.01 ± 0.11, whereas C 2 = 〈n 2〉/〈n〉2 ~ E cm with ΔC 2/ΔE cm = (1.81 ± 0.14)·10?3. 相似文献
19.
Ull Erich 《Zeitschrift für Physik A Hadrons and Nuclei》1969,227(1):25-44
With the Möβbauer technique the hyperfine splittings of the 67.4 keV transition of61Ni in compounds and alloys have been studied. A magnetic momentΜ 61,4=+ (0,477 ±0.031)Μ n of the first excited state has been determined. From isomer shifts an order of magnitude estimate of the change in radius ofδ〈r 2〉/〈r 2〉=?6· 10?4 can be inferred. The electric quadrupole interaction of the first excited level has been observed in Ni-J-boracite. In addition the hyperfine fields at the nickel sites were determined in the alloy series Ni x Fe1-x (0≦x≦1). In one case an effect of polarization in a high external field is measured. The fields in some rare earth (RE) intermetallic compounds of the form RENi2 were deduced from linewidth to be less than 15 kOe. 相似文献
20.
It is well known that the observation of a nonzero Fermi matrix element for a β-transition between states that differ in isospin can provide information about the relative isospin purity of the states involved. We have determined the log ft value for the 0+ → 0+ (ΔT ≠ 0) β-transition in decay as 6.516 ± 0.020. From this log ft value, we have deduced |MF| = (43.4 ± 1.1) × 10?3, |α| = (21.7 ± 0.6) × 10?3 and |〈VCD〉| = 41.7 ± 1.1 keV, where MF,α2 and 〈VCD〉 represent the Fermi matrix element, isospin impurity and Coulomb matrix element, respectively. The Coulomb matrix element of 41.7 keV found for 64Ga is one of the largest known from β-decay experiments. The experimental procedure involved a careful measurement of the intensity of the annihilation radiation relative to that of the other γ-rays from 64Ga decay. As a by-product, we have obtained an improved 64Ga decay scheme. We have also summarized the existing information on the isospin impurities of nuclear states as deduced from β-decay experiments. 相似文献