Comparison of Pulse Shape Discrimination Characteristics in Three Organic Scintillators for a High Resolution Coded-Aperture Neutron Imager

Pulse shape discrimination performances of single stilbene crystal, EJ-299-33 plastic and 6 Li loaded plastic scintillators have been compared. Pulse Gradient Analysis pulse shape discrimination algorithm has been tested for each scintillator sample, assessing their neutron/gamma separation. In this study each scintillator sample was irradiated with a 252Cf neutron source and, a real-time fast digitiser was used to collect the data. The figure-of-merit was utilised to compare the discrimination quality of the tested scintillator samples

Digital Neutron-Gamma Discrimination Performance of Stilbene in Comparison with Plastic Scintillators

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Information in the term structure of yield curve volatility

We study information in the volatility of US Treasuries. We propose a no-arbitrage term structure model with a stochastic covariance of risks in the economy, and estimate it using high-frequency data and options. We identify volatilities of the expected short rate and of the term premium. Volatility of short rate expectations rises ahead of recessions and during stress in financial markets, while term premium volatility increases in the aftermath. Volatile short rate expectations predict economic activity independently of the term spread at horizons up to one year, and are related to measures of monetary policy uncertainty. The term premium volatility comoves with a more general level of economic policy uncertainty. We also study channels through which volatility affects model-based inference about the yield curve

Electronic structure of the sigma-phase in paramagnetic Fe-V alloys. Experimental and theoretical study

The electronic structure of $\sigma$-phase Fe$_{100-x}$V$_x$ compounds with 33.3 $\le x \le 60.0$ was calculated from the charge self-consistent Korringa-Kohn-Rostoker method. For the first time, charge densities $\rho_A(0)$ and electric field gradients were determined at Fe nuclei, that occupy five nonequivalent lattice sites. The highest $\rho_A(0)$ values were found on sites A and D, and the lowest one on site B, the difference ranging between 0.162 and 0.174 $\it s$-like electrons per Fe atom for $x = 33.3$ and $x = 60$, respectively. The calculated quantities combined with experimentally determined site occupancies were successfully applied to analyze $^{57}$Fe M\"ossbauer spectra recorded on a series of 8 samples in a paramagnetic state.Comment: 4 pages, 4 figures, 15 reference