The rotational dynamics of spherical, conducting dust grains in collisionless plasmas due to asymmetric momentum and current collection in the presence of a uniform magnetic field was modeled using the Monte Carlo code DiMPl. The dependence of the torque, equilibrium rotation rate, and equilibration timescale on the strength of the magnetic field and the surface potential was determined. The direction and magnitude of the rotational velocity were found to depend on the sign and magnitude of the surface potential. At a fixed positive charge, dust rotated anti-parallel to the magnetic field due to accumulation of angular momentum from electron impact while at the floating potential, dust rotated parallel to the magnetic field. This model was used to explain existing experimental observations of isolated dust grain rotation in low temperature discharges. In isothermal tokamak plasmas, equilibrium rotation rates of the order 105 Hz are anticipated to occur over time-scales of 20 ms which will have important consequences for dust dynamics.

A silicon surface-barrier detector may be evaluated by determining certain parameters from a fission fragment energy spectrum recorded by that detector. This paper describes the computer program ANLZE which determines these spectrum parameters in a consistent manner by using a combination of smoothing and fitting routines in the analysis of the data. The effect of the statistical uncertainty of the data on the values of the parameters determined by the program is discussed for various fitting procedures.

The measured yield of K x rays emitted from fission fragments of Cf 252 is reported as a function of the time after fission for times between 1 and 56 nsec, and as a function of the mass of the fragment emitting the x ray. In the experiment, three-parameter data were recorded event by event. The first and second parameters contained information about the energies of both fission fragments from which it was possible to calculate the mass of each fragment. The third parameter contained a signal that was proportional to the time that elapsed between the detection of one of the fission fragments and the detection of an x ray. The timing data were sorted to yield x-ray timing spectra for fission-fragment mass intervals 4 amu wide. Each timing spectrum was fitted with a function that was derived from folding the prompt-response function of the system into a sum of three exponential decays. This analytical technique permitted the determination of the percent of the total x-ray emissions coming from each of the three half-life groups. These results, in conjunction with the yield data, were then interpreted in terms of fragment excitation states and comparisons were made with previously reported data.

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It has been known for more than a century that, counter to one’s intuition, the frequency of occurrence of the first significant digit in a very large number of numerical data sets is nonuniformly distributed. This result is encapsulated in Benford’s law, which states that the first (and higher) digits follow a logarithmic distribution. An interesting consequence of the counter intuitive nature of Benford’s law is that manipulation of data sets can lead to a change in compliance with the expected distribution—an insight that is exploited in forensic accountancy and financial fraud. In this investigation we have applied a Benford analysis to the distribution of price paid data for house prices in England and Wales pre and post-2014. A residual heat map analysis offers a visually attractive method for identifying interesting features, and two distinct patterns of human intervention are identified: (i) selling property at values just beneath a tax threshold, and (ii) psychological pricing, with a particular bias for the final digit to be 0 or 5. There was a change in legislation in 2014 to soften tax thresholds, and the influence of this change on house price paid data was clearly evident.