CVD diamond for beta particle detection in a gamma-ray background

In this paper, Neutron Activation Technique (NAT) is used for neutron flux mapping in homogenous boron concentrated paraffin wax. For this purpose, activator detectors were prepared by irradiating process in an Americium-Beryllium (241Am–9Be) neutron field for the required time period to induce approximate saturation activity. After this, the induced activity was measured by time coincidence method using a Sodium iodide (thallium) NaI (Tl) crystal detector and organic scintillation “Anthracene” detector for gamma ray and beta particle detection respectively. The activator detectors were activated at different radii from the irradiator neutron source in boron mixed paraffin wax. The flux profile was mapped by measuring induced activity. Errors in measurements and calculations were estimated by Poisson distribution.

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Vertically Integrated Amorphous Silicon Particle Sensors

MRS Proceedings ◽

10.1557/proc-808-a10.7 ◽

2004 ◽

Vol 808 ◽

Cited By ~ 5

Author(s):

N. Wyrsch ◽

C. Miazza ◽

S. Dunand ◽

A. Shah ◽

D. Moraes ◽

...

Keyword(s):

Amorphous Silicon ◽

Material Properties ◽

Dark Current ◽

Silicon Particle ◽

Particle Beam ◽

High Energy ◽

Beta Particle ◽

Particle Detection ◽

Glass Substrates ◽

Hydrogenated Amorphous

ABSTRACTVertically integrated particle sensors have been developed using thin-film on ASIC technology. Hydrogenated amorphous silicon n-i-p diodes have been optimized for particle detection. These devices were first deposited on glass substrates to optimize the material properties and the dark current of very thick diodes (with thickness up to 50 m). Corresponding diodes were later directly deposited on two types of CMOS readout chips. These vertically integrated particle sensors were tested in beta particle beam from 63Ni and 90Sr sources. Detection of single low- and high- energy beta particle was achieved.

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Secondary gamma rays excited by the passage of neutrons through matter

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1935.0127 ◽

1935 ◽

Vol 150 (871) ◽

pp. 637-668 ◽

Cited By ~ 21

Keyword(s):

High Pressure ◽

Gamma Rays ◽

Alpha Particle ◽

Ionization Chamber ◽

Gamma Ray ◽

Beta Particle ◽

Nuclear Excitation ◽

Ionization Chambers ◽

Scattering Material ◽

Pass Through

It is well known that the absorption of neutrons in their passage through matter is due to nuclear collisions, and not appreciably to interaction with extranuclear electrons. A collision of a neutron with a nucleus may result in the scattering of the neutron, or in the disintegration of the nucleus. The experiments of Feather and of Harkins, Gans, and Newson§ have shown that several light elements, C, N, O, F, Ne are disintegrated, the mechanism probably being absorption of the neutron and emission of an alpha particle. Fermi|| has reported that a variety of elements when bombarded by neutrons show the phenomenon of induced radioactivity, emitting beta rays. He suggests that the disintegration process takes place usually by absorption of a neutron and emission of an alpha particle or proton, the resulting nucleus being an unstable radio element, transforming into a stable body by emission of a beta particle. The experiments here to be described show that when neutrons pass through various substances, gamma rays are produced. The origin of this radiation has not definitely been established; nuclear excitation appears to be the most plausible explanation in most cases. 2—Experimental Method The general method consisted in measuring the ionization current produced by a Po + Be source (usually of about 10-15 millicuries) placed above a high pressure ionization chamber, and observing the increased ionization when a block of scattering material was placed immediately above the source. A correction was applied for the diminution of the natural effect caused by the scatterer. The increase in ionization amounted usually to 2-3%, and thus to obtain even a rough measurement of the effect, accurate measurements of the ionization currents were required. For this reason the high pressure ionization chamber was usually used in preference to the counter, since measurements to one part in a thousand are impracticable with the latter. The ionization method has, however, the disadvantage that both gamma rays and neutrons are detected. To distinguish between the two radiations, two similar ionization chambers were used, one containing argon at a pressure of 90 atmospheres, the other hydrogen at about 60 atmospheres. The former is more sensitive to gamma radiation, the latter to neutrons. The ionization chambers were of steel and had cylindrical walls 1 cm thick; the radiations entered through the roofs of the chambers, which were 2·5 cm thick. The inside dimensions were 16 cm high and 12 cm diameter, with a 2-cm diameter central electrode. Collecting potentials of 250-500 volts were used. Measurements were made by a balance method and followed standard practice. From the measurements of ionization currents in argon and hydrogen estimates may be made of the neutron ( n ) and gamma ray (γ) intensities separately. The method by which this is achieved is described in § 11.

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Beta-particle feeding distributions for 138–141Cs from total absorption gamma-ray spectrometer (TAGS)

Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment ◽

10.1016/0168-9002(94)91803-1 ◽

1994 ◽

Vol 339 (1-2) ◽

pp. 189-199 ◽

Cited By ~ 10

Author(s):

R.G Helmer ◽

R.C Greenwood ◽

K.D Watts ◽

M.H Putnam

Keyword(s):

Gamma Ray ◽

Beta Particle ◽

Total Absorption ◽

Gamma Ray Spectrometer ◽

Particle Feeding

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Semiconductor detectors

Particle Detectors ◽

10.1093/oso/9780198858362.003.0008 ◽

2020 ◽

pp. 255-372

Author(s):

Hermann Kolanoski ◽

Norbert Wermes

Keyword(s):

Particle Physics ◽

Nuclear Physics ◽

Gamma Ray ◽

Semiconductor Detectors ◽

Silicon Detectors ◽

Particle Detection ◽

Semiconductor Physics ◽

Pixel Detectors ◽

Drift Chambers ◽

Electronic Measurement

Already since the early 1960s semiconductor detectors have been employed in nuclear physics, in particular for gamma ray energy measurement. This chapter concentrates on position sensitive semiconductor detectors which have been developed in particle physics since the 1980s and which feature position resolutions in the range of 50–100 μ‎m by structuring the electrodes, thus reaching the best position resolutions of electronic detectors. For the first time this made the electronic measurement of secondary vertices and therewith the lifetime of heavy fermions possible. The chapter first conveys the basics of semiconductor physics, of semiconductor and metal-semiconductor junctions used in electronics and detector applications as well as particle detection with semiconductor detectors. It follows the description of different detector types, like strip and pixel detectors, silicon drift chambers and charged-coupled devices. New developments are addressed in the sections on ‘Monolithic pixel detectors’ and on ‘Precision timing with silicon detectors’. In the last sections detector deterioration by radiation damage is described and an overview of other semiconductor detector materials but silicon is given.

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