共查询到20条相似文献,搜索用时 281 毫秒
1.
R.E. Warner D.C. Martin G.C. Ball W.G. Davies A.J. Ferguson D. Horn 《Nuclear Physics A》1979,326(1):209-224
We have searched for double spectator pole events in the reaction , such that the deuteron from the projectile goes forward with the beam velocity while α or d from the target remains at rest. Triple coincidence studies of the reaction show such events, but with the 0° deuteron energy spectrum peaked at slightly higher velocities. Similar effects are seen in d-6Li double coincidence spectra from the single breakup reaction . Quasi-free inelastic scattering, where the d from the projectile receives no momentum transfer while the α excites the target to its first excited state, is also shown to be an important mechanism. 相似文献
2.
The cross section, vector analyzing power, and proton polarization have been measured for the ln = 0 reaction 116Sn(d, p)117Sn(g.s.) at 8.22 MeV. In addition, cross section and analyzing power data have been obtained at 8.22 MeV for and for 116Sn(d, p)117Sn leading to excited states of 117Sn at 0.159, 0.317, 1.020, 1.179, 1.308 and 1.497 MeV. The cross section and analyzing power for and for leading to the 1.294 MeV state of 116Sn have also been measured at 12.91 MeV. The data for 116Sn(d, p)117Sn(g.s.) have been used to separate the contributions to the analyzing power arising from spin-dependent forces in the proton and deuteron channels. A similar analysis is presented for an transition at 11 MeV. Optical-model analyses have been performed for the elastic scattering data. The reaction data have been compared with distorted-wave calculations in order to investigate the validity of various deuteron potentials, as well as to extract spectroscopic information. 相似文献
3.
H.G. Kirk R. Schulte P. Sixel M. Klein M. Walter M.J. Counihan D.J. Kocher P. Kostka P.K. Malhotra D.R.O. Morrison H. Saarikko K.L. Wernhard K.W.J. Barnham R.M. Eason D.P. Dallman F. Mandl M. Markytan 《Nuclear Physics B》1976,116(1):99-117
The inclusive production of K?1(890) and K?1(1420) is studied in K??p interactions at 10 and 16 GeV/c. At 10 GeV/c an enhancement in the () mass distribution is found at 1.74 GeV, but no clear signal is seen at 16 GeV/c. The fraction of coming from decay of the is large, being (50 ± 6)% and (45 ± 5)% at 10 and 16 GeV/c, respectively. The inclusive cross sections for K1?(890) and production are almost constant with energy from 8 to 32 GeV/c with values of 3.5 and 3.3 mb, respectively. The production cross section is studied as a function of transverse and longitudinal variables and found to derive mainly from fragmentation of the incident K? meson. The spectra of resulting from the decay of are studied. 相似文献
4.
Angular distributions of the vector analyzing power and the absolute cross section were measured for the 58Ni(d, p)59Ni reaction at a deuteron energy of 10 MeV. The observed j-dependence of the vector analyzing power allowed unambiguous spin assignments for the following states in 59Ni with excitation energies in ; ; . The data are well reproduced by DWBA calculations employing deuteron and proton optical model parameters obtained from analyses of elastic scattering cross sections and polarizations. A tentative spin assignment of is made for the level at 3.061 MeV. A assignment to the level at 3.538 MeV is suggested on the basis of the empirical behavior of the j-dependence of the vector analyzing power for l = 2 transitions. Measurements of the vector analyzing power for the four low-lying 59Ni states formed by l = 1 transfer were made for angles from 2.5° to 15° using a magnetic spectrograph. A very strong j-dependence was observed for these far-forward-angle measurements in agreement with DWBA predictions. 相似文献
5.
Angular distributions of γ-rays from the 2H(d, γ)4He reaction have been measured at the deuteron energies Ed = 6.05, 8.96 and 11.67 MeV with a 12.7 cm × 15.2 cm NaI(Tl) crystal enclosed in a Cerenkov anticoincidence shield. A least-square fit of the angular distributions indicates that the differential cross section is proportional to sin2θ cos2θ and that the process proceeds through an E2 transition of the type . 相似文献
6.
James A. Thomson 《Nuclear Physics A》1974,227(3):485-505
reactions have been studied with 10 MeV vector polarized deuterons over the angular range 15° ≦ θp ≦ 80°. Angular distributions of the vector analysing power and the differential cross section have been measured for reactions leading to levels in 57Fe. Distorted wave Born approximation calculations are compared to the measurements. The observed j-dependence of the vector analysing power results in eighteen new spin-parity assignments for levels in 57Fe. Spectroscopic factors are extracted from the differential cross-section measurements. The results are compared to the predictions of the single-particle shell model and to models including collective structure. 相似文献
7.
The reaction has been studied in a kinematically complete experiment using a tensor-polarized deuteron beam to investigate the isospin-forbidden pn final-state interaction. A clear dependence of the cross section near Epn = 0 on the spin state of the incoming deuterons has been found as expected if the bumps observed by several authors at small pn relative energies are indeed due to the isospin-forbidden proton-neutron FSI in the 1S0, T = 1 state. 相似文献
8.
The cross sections for proton capture by 11B to the ground and excited states of 12C have been measured in the proton energy interval between 18 and 43 MeV. The ground-state cross section shows good agreement with theoretical calculations including correlations. Capture photons have also been observed to all the residual 1p-1h states of 12C having a dominant hole: the corresponding cross sections systematically show a giant resonance whose energy increases with the increasing excitation energy of the “background” level. The resonances at 27.4, 31, 33.2, 37 and 43 MeV, seem to show observable interference effects. 相似文献
9.
E. Arai M. Futakuchi H. Kamada J. Komaki T. Matsuzaki M. Ogawa Y. Oguri 《Nuclear Physics A》1982,378(2):259-272
Using a proton beam with an overall resolution of 300–400 eV (FWHM) spins, parities and partial widths were determined for all resonances observed (99 s-wave, 42 p-wave, 106 d-wave and one g-wave resonances). Differential cross sections for proton elastic scattering from 56Fe were measured at proton energies between 3.1 and 4.2 MeV. Spectroscopic factors and Coulomb displacement energies were extracted for the fragmented analogue resonances which correspond to the , and states in 57Fe. A value of the s-wave proton strength function was deduced. 相似文献
10.
11.
R. Kroth S.K. Bhattacherjee C. Günther M. Guttormsen K. Hardt H. Hübel A. Kleinrahm 《Physics letters. [Part B]》1980,97(2):197-199
The g-factors of the 10+ isomeric states in 194Hg and 196Hg have been measured using the in beam IPAD method. The results and are in agreement with the value expected for an (?2) neutron satructure and clearly contradict the previous assignment as () proton configurations. Cranking model calculations show that the neutron excitation energies in the rotating frame agree satisfactorily with the experimental energies and that the proton excitations are expected ≈2 MeV above the experimental yrast line 相似文献
12.
W.C. Haxton 《Nuclear Physics A》1981,367(3):517-525
The solar neutrino capture rate for the reaction is calculated for the standard solar and weak interaction models. The results show that the capture cross section is dominated by the lowest Gamow-Teller transition to the metastable state in 81Kr. As the inverse electron capture rate for this transition has been measured recently, one can then argue that the cross section is well determined experimentally. Thus uncertainties in nuclear physics should not be an obstacle to the recently proposed 81Br radiochemical measurement of the 7Be solar neutrino flux. 相似文献
13.
Although the ground states of 151Eu and 153Eu both have , the (p, t) transition connecting these states is extremely weak. A level at 261 keV with a large (p, t) cross section is assigned as the deformed [413] state in the “spherical” nucleus 151Eu. 相似文献
14.
The analysing power of the reaction for vector and tensor polarization of an 800 keV deuteron beam, as well as the relative cross section for the unpolarized beam were measured at 7 to 9 angles between 0° and 160°, using a thick target. Analysis in terms of (l, s, Jπ) matrix elements shows that two intermediate states with and present, strongly interfering with each other. Assignments to known 9Be levels and to threshold resonances as suggested by Hackenbroich and Seligman are briefly discussed. The magnitude of the vector analysing power makes the reaction interesting as a monitor for the vector polarization of low-energy deuteron beams. 相似文献
15.
P. Hille K. Rudolph M. Hille P. Sperr W. Mannhart H. Münzer G. Gaul 《Nuclear Physics A》1976,266(1):253-261
The total fusion cross section for the system 35Cl+48Ti was measured at . Evaporation residues are identified by a time-of-flight mass spectrometer using a pulsed beam and solid state fission detectors. In addition, the mass yields of evaporation residues were measured by activation analysis. The results are compared to statistical model predictions. 相似文献
16.
D. Chultem V.S. Evseev V.M. Sidorov V.A. Khalkin R. Engfer H.H. Müller H.K. Walter 《Nuclear Physics A》1979,316(3):290-294
A search for the existence of the tetraneutron has been made using the double charge exchange reaction residuals for 4n production and the capture process in the same target, , for the 4n detection. No event has been found, giving an upper limit for the product of the production cross section σp, the detection cross section σd and the 4n lifetime τ. Assuming 10?18 ≦ τ ≦ 10?9 sec it follows that σpσdτ ≦ 2.5 × 10?65cm4 sec with 90 % confidence, and for with 90 % confidence. The magnitude of this value is comparable to the experimental limit of the 4He(π?, π+)4n cross section. 相似文献
17.
The reaction was studied using 17 MeV polarized tritons from the tandem Van de Graaff accelerator at the Los Alamos Scientific Laboratory. The α-particles were analyzed using a Q3D magnetic spectrometer and detected with a helical-cathode position-sensitive counter. The overall resolution was ~ 18 keV FWHM. Measurements of the 150Nd(3He, d)151Pm reaction were made using 24 MeV 3He beams from the McMaster University tandem accelerator. The deuteron spectra were analyzed with a magnetic spectrograph using photographic emulsions for detectors, yielding a resolution of ~ 13 keV FWHM. By comparing the measured angular distributions of () and (3He, d) cross sections and () analyzing powers with DWBA predictions it was possible to assign spins and parities to many levels. The present results confirm earlier assignments of rotational bands based on the low-lying orbitals. In addition, states at higher excitation have now been assigned to the orbitals, and members of the bands are tentatively proposed. The spectroscopic strengths can be explained reasonably well by the Nilsson model when pairing and Coriolis mixing effects are included. 相似文献
18.
Three-body break-up in n-p final-state interaction regions has been investigated through the reactions . In all cases, the proton and the neutron were detected at the same angle in a kinematically complete experiment for a deuteron bombarding energy of 27.5 MeV. Helium and deuterium gas targets in a small gas cell cooled with liquid nitrogen were used. No indication of any possible contribution from the (isospin-forbidden) 1S0 p-n final-state interaction was observed in the first three reactions. For the 3He + d reaction, the data shown pronounced enhancements due to the p-n final-state interaction. In the forward regions the observed peaks are broader than the predictions of final-state interaction models. 相似文献
19.
G. Köbschall E. Fein C. Ottermann K. Maurer K. Röhrich Ch. Schmitt V.H. Walther 《Nuclear Physics A》1984,412(2):294-300
Double differential cross sections for electron-3He scattering leading to continuum states were measured between break-up threshold and the region of quasi-free interaction in a momentum transfer range of . The cross sections for the quasi-free scattering calculated in plane-wave impulse approximation were found to be in good agreement with the experimental results for momentum transfer . 相似文献
20.
Differential cross sections, vector and tensor analysing powers have been measured for the 61Ni(d, p) reaction at a deuteron energy of 12.3 MeV. Most of the 30 transitions observed below 8.5 MeV excitation are dominated by a single j-value, which was determined from behaviour of the analysing power data. For a number of transitions it was possible to make unambiguous j-assignment relying on the established j-dependence of the T22 tensor analysing power. The deduced spectroscopic factors indicate that the full strength of neutron transfer to the () and orbits was found and seven transitions were located above 5.3 MeV. The separated strengths of the transitions are compared with shell-model calculations for the low-lying states of 62Ni. 相似文献