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1.
The vector polarization transfer coefficient Kyy and the tensor analyzing power Azz have been measured for the 2H(dn)3He reaction at θ = 0° over an incident deuteron energy range from 1 to 15 MeV in 0.5 MeV steps. The results agree with the previous 2H(dn)3He measurements of Simmons et al. and are nearly identical to the 2H(dn)3H measurements of Clegg et al. in the region of overlap. The present results provide an accurate and complete set of the observables necessary to use the 2H(d,n)3He reaction as a source of polarized neutrons.  相似文献   

2.
Angular distributions of the differential cross section and the three tensor analyzing powers were measured for the reactions 117Sn(d, p)118Sn and 119Sn(d, p)120Sn at Ed = 12 MeV. In addition, excitation functions of the tensor analyzing power T20 were measured at proton lab angles of 0° and 5° for energies ranging from 10 to 12 MeV. At forward angles, the tensor analyzing powers for the ground state (ln = 0) transitions are more than an order of magnitude larger than the predictions of distorted-wave calculations which neglect the deuteron D-state. Qualitative agreement with the measurements is obtained when the D-state is included.  相似文献   

3.
Measurements have been made of seven polarization transfer coefficients for the 2H(d, p)3H reaction. The experiment used a polarized deuteron beam from the Los Alamos Scientific Laboratory Lamb-shift polarized ion source, a liquid-nitrogen cooled deuterium gas target, a magnetic quadrupole triplet for focusing the reaction protons and a helium filled polarimeter for simultaneously measuring the proton polarization along two transverse axes. Results have been obtained at 10 MeV and for lab angles of 15, 30, 45 and 60 degrees for the vector transfer coefficients Kxx, Kyy and Kzx, and the tensor transfer coefficients Kxxy, Kyyy, Kzzy and Kxzy.  相似文献   

4.
Neutron pick-up cross sections and vector analyzing powers have been measured for the reaction 55Mn(d, t)54Mn at 17 MeV. The mixture of p12 to p32 transfer to the low-lying ln = 1 states has been found. Evidence of the f72 hole nature of several strong ln = 3 states above 1 MeV has been obtained.  相似文献   

5.
Exact finite-range DWBA analyses of (d, t) and (dd, 3He) reactions have been performed for an 64Zr target at an incident deuteron energy of 13.0 MeV, leading to the ground states of the residual nuclei. The microscopic overlap functions for (d, t) and (d, 3He) systems obtained by using the Phillips triton wavefunctions have been used as projectile form factors into the calculation. The results are compared with zero-range DWBA calculations taking the finite-range effects into account by means of a local energy approximation. The results obtained by finite-range and zero-range calculations for differential cross sections as well as vector and tensor analysing powers are compared with the experimental data. The range of validity of the local energy approximation is discussed.  相似文献   

6.
Angular distributions of cross sections [α(θ)] and vector analyzing powers [iT11(γ)] have been measured for seven low-lying states or groups of states excited by the 48Ca(d, t)47Ca reaction with 13.5 MeV deuterons and analyzed by the DWBA. On the basis of comparison of vector analyzing powers with DWBA calculations, spin-parity assignments have been made or confirmed for several states. Spectroscopic factors have been extracted. Angular distributions for weak states at 3.30 and 3.57 MeV excitation in 47Ca could not be reproduced by DWBA calculations. Investigations of compound nucleus and multi-step contributions to the cross sections and analyzing powers for these states have been made by means of Hauser-Feshbach and CCBA calculations. Optical model parameters were obtained from analysis of 13.5 MeV deuteron elastic scattering cross sections and analyzing powers.  相似文献   

7.
The analyzing powers iT11, T20, T21 and T22 have been measured for the reaction 3He(d, p)4He at laboratory energies of 344, 465 and 727 keV. A polarized deuteron beam was used with quantization axis oriented perpendicular to and at 54.7° to the incident beam direction. With semi-conductor proton detectors in two perpendicular planes all four analyzing powers could be determined. The beam polarization was determined using the 3H(d, n)4He reaction at a mean energy of 130 keV. The uncertainty in this analyzing power and the effect on the results is discussed. The analyzing powers have been fitted to a Legendre polynomial expansion to four or five terms and the resulting coefficients tabulated. The results indicate that d-waves contribute to the reaction only through the 4D32 entrance channel and their contribution falls off both above and below the 32+ resonance at 430 keV.  相似文献   

8.
Angular distributions of the vector analysing power and the cross section were measured for 90Zr(d, p)91Zr. Measurements were made on two transitions at a deuteron energy of 11 MeV and on 20 transitions at 12 MeV. The observed j-dependence of the vector analysing power provided unambiguous spin assignments for most final states. Measurements of the cross section and vector analysing power were also made for deuteron elastic scattering at 11 MeV in order to determine the potential parameters for DWBA calculations. The DWBA predictions are in good agreement with the measured (d, p) cross sections and in qualitative agreement with the analysing powers. Enriched targets.  相似文献   

9.
The cross section and the analyzing powers Ay, Axx and Ayy for the reaction 4He(d, αp)n are studied with kinematically complete measurements at incident energies of 12 and 17 MeV. Spectral structures due to the final-state interactions and quasifree scattering are measured. A three-body model of the Faddeev type gives a satisfactory fit to the cross-section and Ay data, but it fails to fit adequately the tensor analyzing-power data. The tensor analyzing powers in the breakup process should be sensitive to the input two-body force, and that sensitivity seems to be somewhat greater near the three-body 1+ resonance.  相似文献   

10.
The 54Fe(p, d)53Fe and 140Ce(p, d)139Ce reactions have been studied at a proton energy of 122 MeV. Analyzing powers and angular distributions were obtained for outgoing deuterons to the strong low-lying single-particle states in both nuclei. These data along with the data of others at 26, 29, 41, 52 and 24, 35, 55 MeV for 54Fe and 140Ce respectively, have been compared with exact-finite-range DWBA calculations carried out in a consistent fashion to determine the energy dependence of the spectroscopic factors. A strong energy dependence was noticed for the spectroscopic factors when the l-values were large.  相似文献   

11.
12.
The microwave spectra of the d3 species of intramolecularly hydrogen-bonded 2-aminoethanol (ODCH2CH2ND2) as well as the d3-O18, d3-N15 and three d2 isotopic forms have been studied. The rs O-(D)?N distance of 2.8027(5) Å in the d3 species is 0.0058(7) Å shorter than the O-(H)?N distance found earlier for the d0 species (R. E. Penn and R. F. Curl, Jr., J. Chem. Phys.55, 651–658 (1971)). The anomalous rs structural parameters rOH = 1.14 A? and ∠COH = 103.7°, when corrected for the systematic error caused by the O?N “shrinkage” upon deuteration, become 1.00 Å and 108°, respectively.  相似文献   

13.
The tensor analyzing power fzz has been measured for the 3He(d, p)4He reaction at 0 = 0° over an incident deuteron energy range Ed = 6.6–15.8 MeV in steps of 0.5 MeV. The present results agree with and extend the previous measurements of Grüebler et al. The present results indicate that this reaction is a very good tensor analyzer for polarized deuteron beams with energies up to 15.8 MeV.  相似文献   

14.
It is shown that the pseudoscalar ηc and “ηc” (ηb and “ηb”) with M ≈ 2.80 and 3.51 GeV (9.17 and 9.88 GeV) can be predicted by using the radial mixing model, where the “ηc” and “ηb” are the excited 0- states in the c-c and b-b systems, respectively, and the former would correspond to the observed 0- meson with M ≈ 3.45 GeV in charmonium.  相似文献   

15.
Using the technique of Doppler-free two-photon spectroscopy the energies of the n2S12 (12 ? n ? 35) and n2D32,52 (11 ? n ? 48) states of CsI have been measured with a thermionic detector. The absorption spectrum of molecular iodine was used as a reference giving us a total estimated accuracy of about 2 × 10-7. Taking also into account the energies of the 7–11 2S12 and 5 and 6 2D32,52 states measured by other authors and using an extended Ritz-formula we found the ionization limit to be Ei = 31406.468 ± 0.006 cm-1.  相似文献   

16.
In reactions such as ee → anything, NN → anything, the final state (neglecting secondary isospin violating decays) is customarily supposed to have isospin zero or one. We show that for such states the average fraction (X) of the energy carried away by neutral pions is bounded by X<(9+√41)20≈0.77, when I3 = 0 (e.g., for ee, pp, nn) and by X>(11?√41)40≈0.115, when I3=±1 (e.g., for pn or np).  相似文献   

17.
The s-dependence of dσdt at fixed t reveals important features of the underlying mechanism. In particular, it can clarify the origin of the structure near t = ?1.2 in high-energy pp elastic scattering. If this structure comes from destructive interference between two terms of different energy dependence (e.g. between single and double pomeron exchanges), the plot of ln dσdtversus ln s in the interference region will show an inflexion or dip; dσdt may even rise with increasing s through a limited interval. Other mechanisms have no such feature. We give illustrations and stress the interest of measurements in the NAL and ISR momentum range.  相似文献   

18.
The 68Zn(d, α)66Cu reaction populating low-lying states in 66Cu has been studied at θlab = 4° using deuteron beams in the energy range 9.0 to 10.5 MeV. Tensor analyzing powers were calculated and natural- or unnatural-parity assignments were made for thirteen states in 66Cu. By combining these results with existing limits unambiguous Jπ assignments of 2+, 2+, 2+ and 1+ have been made for the levels at 186, 465, 822 and 1344 keV respectively. The previous tentative assignments to seven other levels have been confirmed while that for the 1247 keV level has been shown to be incorrect. The identification of the quartet of levels based on the π(P32)v(f52) configuration has been confirmed.  相似文献   

19.
Measurements on the superconducting critical temperature Tc and critical field, Hc, of ZnCr and ZnMn alloys, down to 0.037°K are presented.The variation of Tc with increasing concentration depends strongly on Tcp/θ, with θ a characteristic temperature, while effects of Hc are similar to previously studied alloys.  相似文献   

20.
We have measured the resistivity of AlMg and AlMn up to 0.5 at. % impurity concentration between 0° and 100°C. The results for the resistivity for both systems can be analysed within one generalized model in which spinfluctuations as well as changes in the electron-phonon interaction are considered. For AlMn a calculation of the impurity contribution to d?/dT is attempted. For AlMg there are indications that the superconducting Tc will increase with Mg concentration.  相似文献   

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