Evaluation of radiation interaction parameters of some shape memory alloys

In this study, effective atomic number (Zeff), atomic (σta) and electronic cross section (σte) values of some shape memory alloys (SMA) were calculated at energies 5.9, 6.1, 8, 11.2, 25, 59.543, 75, 112, 149 keV. It has been observed that the obtained values of the calculated parameters vary depending on the photon intensity, chemical constitution and density of the alloys. Calculations were made using the WinXCom program and the graph of the change according to the energy of the obtained results was drawn. The results of this study are thought to be beneficial in the application of various fields.

Optical intensity interferometry observations using the MAGIC imaging atmospheric Cherenkov telescopes

Imaging Atmospheric Cherenkov Telescopes (IACTs) currently in operation feature large mirrors and order of 1 ns time response to signals of a few photo-electrons produced by optical photons. This means that they are ideally suited for optical interferometry observations. Thanks to their sensitivity to visible wavelengths and long baselines optical intensity interferometry with IACTs allows reaching angular resolutions of tens to microarcsec. We have installed a simple optical setup on top of the cameras of the two 17 m diameter MAGIC IACTs and observed coherent fluctuations in the photon intensity measured at the two telescopes for three different stars. The sensitivity is roughly 10 times better than that achieved in the 1970’s with the Narrabri interferometer.

Proton Radiation Therapy for Local Control in a Case of Osteosarcoma of the Neck

A 33-year-old man with symptomatic, unresectable osteosarcoma of the neck experienced disease progression despite treatment with multiple systemic agents. Given the tumor location, adjacent to the spinal cord and encasing the brachial plexus, proton beam therapy was recommended instead of conventional photon radiation therapy. The treatment was delivered in 3 weekly 10 cobalt-gray equivalents fractions, and there was minimal associated toxicity. There has been significant improvement in the patient's presenting symptoms as well as radiologically stable disease at 1 year. A photon intensity–modulated radiation therapy plan was created retrospectively for dosimetric comparison and demonstrated noninferiority, thereby highlighting the need for judicious use of proton therapy in certain cases.

FPGA-Based TDC for Single-Photon Intensity Interferometry

A prototype intensity interferometer readout for single-photon detectors is presented as a time-to-digital converter (TDC) implemented on a field-programmable gate array (FPGA). We briefly discuss the history and scientific motivations for the instrument. A comparison is drawn between the use of photomultiplier tubes in linear mode and single-photon avalanche diodes (SPAD) in Geiger mode. Different FPGA-based TDC configurations are discussed. We describe the design and implementation of a four-phase FPGA-based TDC. The paper concludes with the application of the design to investigate SPAD after-pulsing and a description of future work.