Measurement of the real-to-imaginary ratio of the pp forward amplitude at beam momenta between 400 and 730 MeV/c

Differential cross sections of $\text{p}\text{p}$ forward elastic scattering were measured between 400 and 730 MeV/c, and the real-to-imaginary ratio, ?, of the forward amplitude was deduced. We found that ρ increases from ～ 0.1 to ～ 0.4 in this momentum range. A dispersion-relation analysis shows the existence of a pole-like structure in the real part of the $\text{p}\text{p}$ amplitude near threshold.     

Measurement of the proton polarization in deuteron photodisintegration at photon energies between 350 and 700 MeV

The proton polarization in the γd → pn reaction has been measured at a c.m. angle of 90° and photon energies between 350 and 700 MeV, using a carbon polarimeter. The magnitude of the polarization shows a sharp energy dependence with a peak of about ?80% at around 500–550 MeV. This feature cannot be explained by conventional models and seems to indicate a new mechanism in the dibaryon system.     

Van der corput’s difference theorem

We obtain a sufficient condition for a subsetH of positive integers to satisfy that the equidistribution (mod 1) of the sequences (u _n+h − u _n; n=1, 2, ···) for allh ∈H implies the equidistribution of (u _n). Our condition is satisfied, for example, for the following sets: (1)H={n − m; n ∈ I, m ∈ I, n>m}, whereI is any infinite subset of integers; (2)H={| ψ (n)|; ψ(n)≠0,n ∈ Z}, where ψ is a nonconstant polynomial with integral coefficients having at least one integral zero (modq) for allq=2, 3, ···; (3)H={p+1;p is a prime} andH={p − 1;p is a prime}.     

Information of relative pairwise comparisons

We study the amount of information obtained by a set of relative pairwise comparisons. From this point of view, two kinds of entropy are introduced for graphs.