Pseudoscalar mesons in the c-c and b-b systems

It is shown that the pseudoscalar η_c and “η_c” (η_b and “η_b”) 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 “η_c” and “η_b” are the excited 0^- states in the $\text{c-}\text{c}$ and $\text{b-}\text{b}$ systems, respectively, and the former would correspond to the observed 0^- meson with M ≈ 3.45 GeV in charmonium.     

Superconducting properties of ZnCr and ZnMn alloys

Measurements on the superconducting critical temperature T_c and critical field, H_c, of $\text{Zn}$Cr and $\text{Zn}$Mn alloys, down to 0.037°K are presented.The variation of T_c with increasing concentration depends strongly on T_cp/θ, with θ a characteristic temperature, while effects of H_c are similar to previously studied alloys.     

The impurity resistivity and resistivity minima in AlCr and AlMn alloys

The impurity resistivity of $\text{Al}$Cr between 1.5 and 50°K was determined with a characteristic temperature for the T² variation θ₁=960±40°K. The behaviour of the resistivity minimum both in $\text{Al}$Cr and $\text{Al}$Mn alloys with impurity concentration provides evidence that a T³ phonon resistivity is found also in aluminium with anomalous impurity resistivity.     

Magnetostriction of dilute AuYb and AuTb monocrystals

We have made magnetostriction measurements on dilute $\text{Au}$Yb and $\text{Au}$Tb monocrystals at low temperatures. The shape magnetostriction follows the sign of the quadrupolar Stevens factor α_J of the earth but, in contrast to our recent results on silver-rare earth dilute alloys, the 〈001〉 and 〈111〉 effects have opposite signs. We obtain very good agreement between experiment and calculations based on the known cubic crystal-field parameters and we estimate the ion-lattice coupling parameters. The volume magnetostriction is positive, but very small, about two orders of magnitude smaller than the shape effect.     

Angular distribution of polarization transfer in 2H(d, p)3H

Measurements have been made of seven polarization transfer coefficients for the ²H($\text{d}$, $\text{p}$)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 K_x^x′, K_y^y′ and K_z^x′, and the tensor transfer coefficients K_xx^y′, K_yy^y′, K_zz^y′ and K_xz^y′.     

D-state effects in (d, t) and (d, 3He) reactions

The influence of the deuteron and triton [³He] D-state on the form factor required in the DWBA analyses of the ($\text{d}$, t) [($\text{d}$, ³He)] reactions has been studied. The wave functions of Phillips are used for three-nucleon systems because they are designed to yield the correct asymptotic form for the (d, t) and (d, ³He) overlaps. The zero-range parameters D₀ and D₂ which enter into the calculation of the cross section and the tensor analysing power in the DWBA with the local energy approximation are calculated and found to yield values consistent with experimental data.     

Isospin bounds for energy partition in ee and NN annihilation

In reactions such as $\text{e}$e → anything, $\text{N}$N → 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 $\text{X<}\text{(9+√41)}\text{20}\text{≈0.77}$, when I₃ = 0 (e.g., for ee, pp, nn) and by $\text{X>}\text{(11?√41)}\text{40}\text{≈0.115}$, when I₃=±1 (e.g., for pn or np).     

Nuclear magnetic resonance of extremely dilute CrFe

We report nuclear orientation and pulsed NMR on radioactive ⁵¹Cr$\text{Fe}$ samples. The zero-field resonance frequency of 13.543(18) MHz from polycrystalline foil samples yields a hyperfine field B_hf = ?6.655(35) T in the dilute, low-temperature limit for Cr$\text{Fe}$.     

Dispersion relation constraints on low energy KN scattering

The measurements of the real parts of the kaon-nucleon amplitudes are shown to impose, via dispersion relations, powerful constraints on the analysis of low energy K^?p data. These constraints are used in the determination of the S wave $\text{K}$N parameters and in the calculation of coupling constants. We find g_Λ²=13.7±1.9 and g_Σ²?3.7 ± 1.3.     

QQG hybrid mesons in the MIT bag model

We suggest that hybrid (q$\text{q}$g) mesons could exist with rather light masses. The spectrum of the ground state nonets, J^PC = (0, 1, 2)^?+; 1^?? is calculated in the MIT bag model including O(α_s) energy shifts. We discuss hadronic transitions among these states, consider their possible production at LEAR and SPEAR and indicate some interesting decay signatures.     

Carrier drifttime from pulsed photoconductivity in as-grown trans-polyacetylene

Nanosecond pulsed photoconductivity experiments in as-grown trans-polyacetylene at room temperature are reported. From the decay of the photoresponse the free drift time of photogenerated carriers is found to be τ_fd<10^?9sec. From the amount of collected charge the upper limit of τ_fd is reduced to picoseconds so that the relaxation of electrons and holes into $\text{mobile}$ solitons and anti-solitons is questionable.     

Evidence for high mass NN and NNπ enhancements observed in pd interactions at 5.55 GeV/c

Based on 4085 $\text{p}\text{n→Xπ}{}^{\mathrm{?}}$ events, X denoting a neutral $\text{N}$N or $\text{N}\text{Nπ}$ system, we present evidence for 5.1 and 3.1 standard deviation enhancements at the X mass of 2.85 and 3.05 GeV/c², respectively. The lower mass bump has a width of Λ ? 39 GeV/c² while the 3.05 GeV/c² is seen as a one bin accumulation (20 GeV/c² width). The relevance of these peaks is discussed.     

Elastic pp scattering in the cern sps energy region

The pronounced dip-bump structure with a sharp minimum at |t| = 1.5 (GeV/c)², recently observed in elastic $\text{p}$p scattering at P_L = 50 GeV/c at the CERN SPS, is explained by the quark multiple scattering model with a realistic wavefunction for the proton and the antiproton. It is predicted that a second dip will appear around |t| = 7 (GeV/c)² at P_L = 50 GeV/ c and at higher energies.     

The long range forces in KN and KN scattering

We calculate the long range forces in KN and $\text{K}$N scattering and show how they can be used to provide consistent predictions of many experimental results. In particular, we strongly favour the existence of a Z₀¹ resonance near 1700 MeV/c²     

Energies of the n2S12 and n2D32,52 states of Cs

Using the technique of Doppler-free two-photon spectroscopy the energies of the n²S_{$\text{1}\text{2}$} (12 ? n ? 35) and n²D_{$\text{3}\text{2}$,$\text{5}\text{2}$} (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 ²S_{$\text{1}\text{2}$} and 5 and 6 ²D_{$\text{3}\text{2}$,$\text{5}\text{2}$} states measured by other authors and using an extended Ritz-formula we found the ionization limit to be E_i = 31406.468 ± 0.006 cm^-1.     

HD structural isotope effect in hydrogen-bonded 2-aminoethanol

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 r_s 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 r_s structural parameters $\text{r}\text{OH = 1.14}\text{A}\text{?}$ 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.     

Polarization transfer in the 2H(d,n)3He reaction at θ = 0°

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

Deviation from Matthiessen rule in Mg-Cd and Cd-Mg

The interference term between electron-phonon and electron impurity scattering has been evaluated for $\text{Mg}$Cd and $\text{Cd}$Mg and found to be negative, in agreement with experiment. It is shown that measurements on single crystal should give valuable information.     

Experimental susceptibility of CuFe, AgFe and MoFe and the results of the Wilson theory

The low temperature susceptibility of the local moment system $\text{Mo}$Fe has been measured by the Mössbauer effect. The susceptibility for this system and for the system $\text{Cu}$Fe, $\text{Ag}$Fe and $\text{Au}$Fe show general agreement with the prediction of the Wilson theory.     

A generalized VMD mechanism for radiative decays of cc mesons

A generalized VMD mechanism, implemented through the OPC model, is proposed for E1 and M1 decays of $\text{c}\text{c}$ mesons wherein the photon couples to two infinite sequences of radial excitations of ³S₁ and ³D₁$\text{c}\text{c}$ states. The results reveal good accord with data under the conventional assignments, with a parameter signifying a reduced magnetic coupling of ψ-ions with c quarks.