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1.
Shanshan Yu Alireza Shayesteh Dominique R.T. Appadoo 《Journal of Molecular Spectroscopy》2005,229(2):257-265
The X3Σ− ground state vibration-rotation spectrum of SbH and the near infrared spectra of the b1Σ+-X3Σ− transitions of SbH and SbD have been measured at high resolution by Fourier transform spectroscopy. The SbH and SbD radicals were generated in a tube furnace with a D.C. discharge of a flowing mixture of argon, hydrogen (or deuterium), and antimony vapor. In the infrared region, the 1-0 and 2-1 bands of the three components (0+, 1e, and 1f) as well as the 0+ component of the 3-2 band were observed for 121SbH and 123SbH. In the near infrared region, the 0-0, 1-1, and 2-2 bands of the b1Σ+-X3Σ− system of both SbH and SbD as well as the 3-3 band of SbD were observed. Except for a few lines, the antimony isotopic shift was not resolved for these electronic spectra. The present data set was combined with the available ground state data on SbD and a1Δ data for SbH and SbD from previous work, and a least-squares fit was performed for each of the four isotopologues: 121SbH, 123SbH, 121SbD, and 123SbD. Improved spectroscopic constants were obtained for the observed vibrational levels of the X3Σ−, a1Δ, and b1Σ+ states of these four isotopologues. In addition, all the above data were also fitted simultaneously to a multi-isotopologue Dunham model, which yielded Dunham constants and Born-Oppenheimer breakdown parameters for these three electronic states. Interestingly, we found that Born-Oppenheimer breakdown corrections were also required for some of the spin-spin and spin-rotation parameters of the X3Σ− state. 相似文献
2.
The halo-structure of a nucleus is analyzed on the basis of potential energy consideration and separation energy calculations and thereby characterized a nucleus as a halo nucleus. The separation energy analysis showed that 11Be, 14B, 15, 17, 19C, 22N, 23O, 24, 26F, and 29Ne are 1n-halo nuclei since the 1n separation energy S(n) is the lowest and 6, 8He, 11Li, 14Be, 17B, 22C, and 29F are 2n-halo candidates as 2n separation energy S(2n) is the lowest. The potential energy calculations are consistent with the predictions based on separation energy calculations except for 12Be, 19B, and 27F which can be considered as 2n-halo candidates by potential energy consideration. Also, a discrepancy is noticed in the case of the proposed 2n-halo 8He and 17B nuclei. Further, the possibility of emitting halo nucleus via heavy particle decay of heavy nuclei, within the range 82?≤?Z?≤?102, has been studied using the Coulomb and proximity potential model (CPPM). It is observed that the probability of emission of a halo nucleus is lower than that of a normal cluster Nevertheless, there is a finite chance of emission of a halo nucleus in the decay of a heavy nucleus. 相似文献
3.
H. G. Bohlen W. von Oertzen R. Kalpakchieva B. Gebauer S. M. Grimes A. Lenz T. N. Massey M. Milin Ch. Schulz Tz. Kokalova S. Torilov S. Thummerer 《Physics of Atomic Nuclei》2003,66(8):1494-1500
The structure of neutron-rich beryllium isotopes has been investigated using different heavy-ion-induced transfer reactions. In neutron transfer reactions, the population of final states shows a strong sensitivity to the chosen core nucleus, i.e., the target nuclei 9Be or 10Be, respectively. Molecular rotational bands up to high excitation energies are observed with 9Be as the core due to its pronounced 2α-cluster structure, whereas only a few states at low excitation energies are populated with 10Be as the core. For 11Be, a detailed investigation has been performed for the three states at 3.41, 3.89, and 3.96 MeV, which resulted in the most probable spin-parity assignments 3/2+, 5/2?, and 3/2?, respectively. Furthermore, we have studied particle-hole states of 16C using the 13C(12C, 9C)16C reaction and found 14 previously unknown states. Using the 12C(12C, 9C)15C reaction, five new states were observed for 15C. 相似文献
4.
I. Shlimak 《Journal of magnetism and magnetic materials》2009,321(7):884-887
Si, Ge as well as SiGe structures are the promising materials for spintronics and quantum computation due to the fact that in both crystals only one isotope (29Si and 73Ge) has nuclear spin. As a result, isotope engineering of Si and Ge permits to control the density of nuclear spins and vary the spin coherence time, a crucial parameter in spintronics. In the first part we discuss the NMR study of nuclear spin decoherence in Ge single crystals with different abundance of the 73Ge isotope. It was observed that the slow component of the dephasing process is elongated with depletion of Ge crystal with isotope 73Ge. The second part is devoted to the development of the Kane's model of nuclear spin-based quantum computer, which uses the nuclear spin of 31P impurity atoms in a 28Si matrix as quantum bits (qubits). We discuss a new method of placing 31P atoms in a 28Si based on neutron-transmutation-doping of isotopically engineered Si and Ge. In the proposed structure, interqubit coupling is due to indirect hyperfine interaction of 31P nuclear spins with electrons localized in a 28Si quasi-one-dimensional nanowire, which allows one to control the coupling between distant qubits. 相似文献
5.
R. A. Kuzyakin V. V. Sargsyan G. G. Adamian N. V. Antonenko 《Physics of Atomic Nuclei》2013,76(6):716-731
Within the quantum diffusion approach, the capture of a projectile nucleus by a target nucleus is studied at bombarding energies above and below the Coulomb barrier. The effects of deformation of interacting nuclei and neutron transfer between them on the total and partial capture cross sections and the mean angular momentum of the captured system are studied. The results obtained for the 16O + 112Cd, 152Sm, and 184W; 19F +175Lu; 28Si +94,100Mo and 154Sm; 40Ca +96Zr; 48Ca+ 90Zr; and 64Ni +58,64Ni, 92,96Zr, and 100Mo reactions are in good agreement with available experimental data. 相似文献
6.
A. Müller N. Mohan S.J. Cyvin N. Weinstock O. Glemser 《Journal of Molecular Spectroscopy》1976,59(2):161-170
The complete infrared spectrum of gaseous NSCl, including the hitherto unobserved ν3, is reported. A set of force constants for gaseous NSCl consistent with a number of pieces of independent data such as the isotopic shifts (14N32S35Cl, 15N32S35Cl, 14N32S37Cl, 15N32S37Cl, 14N34S35Cl and 15N34S35Cl), centrifugal distortion constants (14N32S35Cl), and the inertia defect (14N32S35Cl) has been computed. Also, the force field of NSF has been redetermined using the vibrational frequencies and the centrifugal distortion constants. 相似文献
7.
OH−- and Cu+-codoped NaCl crystals are colored electrolytically by using a pointed anode and a flat cathode at various temperatures and under various voltages. Absorption and fluorescence spectral properties of colored crystals are investigated. Absorption, excitation and fluorescence spectra reveal existence of V2, V2m, V3, OH−, U, UA, O2−–Va+, O2+, Cu+, Cu0, Cu− and OH−-perturbed Cu+ color centers in colored crystals. Formations of color centers are explained. 相似文献
8.
Using a theory of mode-mode coupling between the two-phonon 0+ mode and the pairing-vibrational mode, we have extensively investigated the first excited 0+(022) states in spherical and transitional nuclei. The results tell us that the 02+ states in a wide range of nuclei are strongly mixed states of both the modes. By making use of these results, the matrix elements for the E0 transitions from the 02+ states to the ground states are calculated for the Zn, Ge, Se, Kr, Sr, Zr, Mo, Ru, Pd, Cd and Sn isotopes. For some of the Cd and Sn isotopes, the matrix elements between the 02+ and 02+ states are also obtained. These numerical calculations make a rather good fit to the E0 experiments. 相似文献
9.
Shanshan Yu 《Journal of Molecular Spectroscopy》2005,230(2):105-116
The vibration-rotation emission spectra for the X2Π ground state and the near infrared emission spectra of the X2Π1/2-X2Π3/2 system of the TeH and TeD free radicals have been measured at high resolution using a Fourier transform spectrometer. TeH and TeD were generated in a tube furnace with a DC discharge of a flowing mixture of argon, hydrogen (or deuterium), and tellurium vapor. In the infrared region, for the X2Π3/2 spin component we observed the 1-0, 2-1, and 3-2 vibrational bands for most of the eight isotopologues of TeH and the 1-0 and 2-1 bands for three isotopologues of TeD. For the X2Π1/2-X2Π3/2 transition, we observed the 0-0 and 1-1 bands for TeH and the 0-0, 1-1, and 2-2 bands for TeD. Except for a few lines, the tellurium isotopic shift was not resolved for the X2Π1/2-X2Π3/2 transitions of TeH and TeD. Local perturbations with Δv = 2 between the two spin components of the X2Π state of TeH were found: X2Π1/2, v = 0 with X2Π3/2, v = 2; X2Π1/2, v = 1 with X2Π3/2, v = 3. The new data were combined with the previous data from the literature and two kinds of fits (Hund’s case (a) and Hund’s case (c)) were carried out for each of the 10 observed isotopologues: 130TeD, 128TeD, 126TeD, 130TeH, 128TeH, 126TeH, 125TeH, 124TeH, 123TeH, and 122TeH. 相似文献
10.
Active yttrium was separated from 235U fission products and the decay of 94Y, 95Y and 96Y to the levels of 94Zr, 95Zr and 96Zr, respectively, has been studied with the aid of a 17 cm3 Ge(Li) detector. Gamma-ray energies and intensities were accurately determined. In the decay of 94Y four new transitions at 1232.78 ± 0.35, 1324.97 ± 0.35, 1363.48 ± 0.35 and 2467.00 ± 2.75 keV were observed. The data obtained support the level scheme proposed for 94Zr by Knight et al. and that deduced from more recent reaction data. Evidence supporting the location of the 0+ excited state at 1300 keV is presented. Branching ratios are calculated and a modified level scheme for 94Zr is proposed. In the decay of 95Y the energies of 13 γ-rays, previously identified with the decay of this nuclide, have been accurately measured and are presented in a partial level scheme for 95Zr. The data obtained in this work support the level structure deduced from reaction data by Cohen and Chubinsky and by other workers. New γ-transitions at 550.10 ± 0.23, 1723.30 ± 0.90 and 1805.0 ± 1.0 keV were measured in the decay of 96Y. 相似文献
11.
From a He-beam excited by electron impact we eliminated the He(21 S) component to better than 0.5% by irradiating light from a He discharge. The quenching process ishv(21 P→21 S)+He(21 S)→He(21 P)→He(11 S +hv) (21 P 1)1 S. By measuring the ions produced in collisions of the He-metastables with various target gases in a mass spectrometer, singlet to triplet Penning-cross section ratios were obtained. These ratios are without exception close to one, which is taken as evidence for the previously proposed electron exchange mechanism of the Penning ionization. In the case that more ions are produced in the collision of He (21 S) and He(23 S) with a target gas, separate relative production cross sections are obtained for the two metastables. For the rare gases the measurements are performed at two temperatures of the He-beam, 320 and 90 °K. It is found that the cross section ratio of associative — to Penning ionization increases considerably as the temperature is decreased for both, He(21 S) and He(23 S), the effect being much more pronounced for He(21 S). The results of this work are found to confirm conclusions drawn from measured energy distributions of the electrons ejected in the Penning process. 相似文献
12.
Jorge E. Spangenberg 《Isotopes in environmental and health studies》2013,49(3):231-238
A preparation of organic working standards for the online measurement of 13C/12C and 18O/16O ratios in biological material is presented. The organic working standards are simple and inexpensive C3 and C4 carbohydrates (sugars or cellulose) from distinct geographic origin, including white sugar, toilet and XEROX papers from Switzerland, maize from Ivory Coast, cane sugar from Brazil, papyrus from Egypt, and the core of the stem of a Cyperus papyrus plant from Kenya. These photosynthetic products were compared with International Atomic Energy standards CH-3 and CH-6 and other calibration materials. The presented working standards cover a 15 ‰ range of 13C/12C ratios and 9 ‰ for 18O/16O, with a precision<±0.2 ‰ for n>10. 相似文献
13.
The mean lifetimes of 15 levels in 30Si and of 7 levels in 30P have been measured by the Doppler-shift attenuation method. Limits on the lifetimes of a further 8 levels in 30Si and of the 3018 keV level in 30P have been obtained. Branching ratios and excitation energies have been measured in both nuclei. The levels were populated by the reactions 27Al(α, p)30Si and 27Al(α, n)30P at α-particle bombarding energies of 5.0, 6.3 and 8.0 MeV. Theγ-rays were detected with a Ge(Li)-NaI(Tl) escape suppressed and pair escape spectrometer. 相似文献
14.
W.C. Ma A.V. Ramayya J.H. Hamilton S.J. Robinson M.E. Barclay K. Zhao J.D. Cole E.F. Zganjar E.H. Spejewski 《Physics letters. [Part B]》1984,139(4):276-278
The energy levels of 182Hg have been identified for the first time through comparison of in-beam studies of the reactions 156,154Gd(32S, 4n)184,182Hg and γ-X-ray coincidences. Levels up to 12+ in 182Hg were established from γ-γ coincidences and singles measurements. The data establish that the ground state shape is near spherical, and that the ground band is crossed by a well-deformed band at 4+. In contrast to IBA model predictions that the deformed band will rise in energy in 182Hg compared to 184Hg, the energies of the deformed levels in 182Hg continue to drop. 相似文献
15.
《Nuclear Physics A》2004,730(3-4):285-298
The 6He+12C elastic and inelastic scattering and the 6He+12C→α+14C reaction have been measured using a 18.0 MeV 6He beam. Experimental results for the elastic scattering are in fair agreement with optical model predictions, using the potentials found in the analysis of 6Li scattering on 12C at similar energies. In triple coincidences, the 6He+12C→10Be+2α reactions were clearly seen, with the 10Be nucleus left in ground and several excited states. The dominant mechanism of this reaction is sequential decay through cluster states of 14C. 相似文献
16.
Shigetō Okabe 《Nuclear Physics A》1984,427(1):87-124
A new technique for calculating the resonating-group-method (RGM) kernels is proposed by use of frequency transformations in order to treat cluster systems involving unequal oscillator frequencies. The present technique is useful for both analytical and numerical deviations of matrix elements of the RGM kernels. The eigenvalue problem of the norm kernel of the RGM is solved for a wide range of systems consisting of an α-particle and a closed-shell nucleus (16O, 40Ca, 48Ca, 56Ni, 80Zr, 90Zr, 120Sn, 140Yb or 208Pb) with realistic oscillator frequencies. These eigenvalues and eigenfunctions are shown to have characteristic features. With these eigenvalues, α-particle reducedwidth amplitudes and spectroscopic factors of the ground states of 20Ne, 44Ti, 94Mo, 124Te and 212Po are calculated by employing simple configurations of the harmonic-oscillator shell model. In heavy nuclei the results with realistic oscillator frequencies are shown to be very different from those with a common oscillator frequency. The effect of the spurious c.m. motion in the generator coordinate method is discussed. 相似文献
17.
A. A. Kulko N. K. Skobelev V. Kroha V. Burjan Z. Hons A. V. Daniel N. A. Demekhina R. Kalpakchieva A. Kugler J. Mrázek Yu. E. Penionzhkevich Š. Piskoř Yu. G. Sobolev E. Šimečková 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(4):538-543
Experimental excitation functions are presented for 45Sc(d, p)46Sc, 45Sc(d, t)44Sc, 45Sc(6He, 5He*)46Sc and 45Sc(6He, α)47Sc reactions at projectile energies near the Coulomb barrier. The obtained excitation functions for reactions 45Sc(d, p)46Sc and 45Sc(6He, 5He*)46Sc have similar behavior and have a maxima near the Coulomb barriers of these reactions. The compilation of the available experimental data, obtained at deuteron- and 6He-energies near the Coulomb barrier, showed that the values of the cross sections at the maxima of the excitation functions obtained in (d, p) reactions and the reactions for one-neutron pickup from the 6He projectiles have a different Z-dependence. 相似文献
18.
19.
J. Gerl G.D. Dracoulis A.P. Byrne A.R. Poletti S.J. Poletti A.E. Stuchbery 《Nuclear Physics A》1985,443(2):348-364
High-spin states in 166W and 167W were populated by the reactions 142Nd(28Si,4n)166W, 142Nd(28Si,3n)167W and 147Sm(24Mg,4n)167W. From the γ-decay the yrast band and a side band (with assumed negative parity) were identified to high spins. There is evidence for a second side band in 167W. The observed backbend of the yrast sequences and band-crossing anomalies in the side bands are discussed in conjunction with cranked-shell-model calculations. A systematic comparison is made between the yrast bands of 166,167,168W in order to understand the structure of the second backbend in 168W. 相似文献
20.
Funaki Y. Tohsaki A. Horiuchi H. Schuck P. Röpke G. 《The European Physical Journal A - Hadrons and Nuclei》2005,24(3):321-342
The states with Jπ = 0+, 2+, and 4+ of 12C with excitation energies less than about 15 MeV are investigated with the alpha condensate wave function with spatial deformation and by using the method of ACCC (analytic continuation in the coupling constant) which is necessary for a proper treatment of resonance states. The calculated energy and width of the recently observed 22+ state are found to be well reproduced. The obtained 22+ wave function has a large overlap with a single condensate wave function of 3α gas-like structure. The density distribution is shown to be almost the same as that of the 02+ state that is regarded as a 3α Bose-condensed state, if the energy of the 22+ state is scaled down to the same value as the one of the 02+ state. Furthermore, the kinetic energy, nuclear interaction energy, and Coulomb interaction energy of the calculated 22+ state are shown to be very similar to those of the 02+ state. We conclude that the 22+ state has a structure similar to the 02+ state of Bose-condensate character with a dilute 3α gas-like structure. In addition, the resonance states, 03+, 04+, 42+, are also discussed. 相似文献