Measurements are presented of the photofission cross section and the mean number fi of neutrons per fission for 232Th made using bremsstrahlung from the Harwell electron linear accelerator HELIOS and a high efficiency neutron detector to record neutron multiplicity distributions. The cross section is interpreted in terms of a fission barrier with shallow wells in two separate outer barriers. In...

Searching for innovative approaches to detect single photons remains at the center of science and technology for decades. This paper proposes a zero transit-time, non-avalanche quantum capacitive photodetector to register single photons. In this detector, the absorption of a single photon changes the wave function of a single electron trapped in a quantum dot (QD), leading to a charge density r...

A passive diffusion method for the determination of radon concentration has been optimised and calibrated. The device consists of a scintillation vial containing activated charcoal, a diffusion barrier and a desiccant agent. The response to diverse atmospheric humidity and variable exposure intervals was studied. The result is a detector independent of atmospheric humidity till 7 days of exposu...

We discuss the propagation of wave packets through interacting environments. Such environments generally modify the dispersion relation or shape of the wave function. To study such effects in detail, we define the distribution function PX(T ), which describes the arrival time T of a packet at a detector located at point X. We calculate PX(T ) for wave packets traveling through a tunneling barri...

We experimentally demonstrate an atom number detector capable of simultaneous detection of two mesoscopic ensembles with single-atom resolution. Such a sensitivity is a prerequisite for quantum metrology at a precision approaching the Heisenberg limit. Our system is based on fluorescence detection of atoms in a hybrid trap in which a dipole barrier divides a magneto-optical trap into two separa...

The notion of " location " physics really needs is exclusively the one of " detection at a given detector " and the time for each such detection is most primitively assessed as the readout of some specific material clock. The redundant abstraction of a macroscopic spacetime organizing all our particle detections is unproblematic and extremely useful in the classical-mechanics regime. But I here...

We discuss the propagation of wave packets through interacting environments. Such environments generally modify the dispersion relation or shape of the wave function. To study such effects in detail, we define the distribution function PX(T ), which describes the arrival time T of a packet at a detector located at point X. We calculate PX(T ) for wave packets travelling through a tunnelling bar...

In vivo transcranial and noninvasive cavitation detection with blood-brain barrier (BBB) opening in nonhuman primates is hereby reported. The BBB in monkeys was opened transcranically using focused ultrasound (FUS) in conjunction with microbubbles. A passive cavitation detector, confocal with the FUS transducer, was used to identify and monitor the bubble behavior. During sonication, the cavita...

In this paper, the sampling current characteristics of external circuit and internal mechanism generation in APD irradiated by a millisecond pulse laser were studied. The photocurrent with different energy densities was obtained resistance circuit. can be divided into stage, conduction stage recovery time domain. This is mainly due to carrier flow APD, which leads lowering barrier between PN ju...