We employ a 32-anode photomultiplier tube (PMT) in a fluorescence detection system and demonstrate its ability to record broad fluorescence spectra at frame rates in excess of 1.4×103 Hz, which is 56× faster than the frame rate of an intensified charge coupled device detector. The multi-anode PMT has single-photon detectable sensitivity. A new data acquisition and processing system for the multi-anode PMT, together with the system-controlling software, has been developed. The performance characteristics of the fluorescence detection system, including the data rate capability, dynamic range, signal-to-noise ratio, and crosstalk among the different anodes, are reported. The 32-anode PMT and acquisition system are suitable for a real-time, field-portable, multichannel optical analyzer.

We present a measurement of the intensity around the focus of a N.A.-0.95 lens using a tapered optical fiber probe. An asymmetry introduced by the vector nature of the incident polarized light is evident, although it is inconsistent with that predicted theoretically by considering the magnitude squared of the electric field. The sensitivity of the probe to different components of the electromagnetic field is considered, and it is shown that the measurement is consistent with vector diffraction theory when the probe properties are taken into account.

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Primordial Black Holes (PBHs), which may have been created in the early Universe, are predicted to be detectable by their Hawking radiation. The Fermi Gamma-ray Space Telescope observatory offers increased sensitivity to the gamma-ray bursts produced by PBHs with an initial mass of ∼ 5 × 10 14 g expiring today. PBHs are candidate progenitors of unidentified Gamma-Ray Bursts (GRBs) that lack X-ray afterglow. We propose spectral lag, which is the temporal delay between the high and low energy pulses, as an efficient method to identify PBH evaporation events with the Fermi Large Area Telescope (LAT).

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