Dispersive property of a G-M tube HV - + In the proportional region a G-M tube has dispersive properties 0 250 500 750 1 10 2 10 4 10 6 10 810 tube voltage.

Slides:



Advertisements
Similar presentations
Radiation Detection ionization chambers (dosimeters, pulse chambers, particle track chambers) scintillation detectors semiconductor detectors photographic.
Advertisements

Lab B4: The Creation and Annihilation of Antimatter SFSU Physics 490 Spring 2004 Professor Roger Bland.
Photoreflectance of Semiconductors Tyler A. Niebuhr.
LECTURE- 5 CONTENTS  PHOTOCONDUCTING MATERIALS  CONSTRUCTION OF PHOTOCONDUCTING MATERIALS  APPLICATIONS OF PHOTOCONDUCTING MATERIALS.
Scintillators. When radiation interacts with certain types of materials, it produces flashes of light (scintillation) Materials that respond this way.
Photomultipliers. Measuring Light Radiant Measurement Flux (W) Energy (J) Irradiance (W/m 2 ) Emittance (W/m 2 ) Intensity (W/sr) Radiance (W/sr m 2 )
X-ray Astronomy Lee Yacobi Selected Topics in Astrophysics July 9.
Department of Aeronautics and Astronautics NCKU Nano and MEMS Technology LAB. 1 Chapter III June 1, 2015June 1, 2015June 1, 2015 Carrier Transport Phenomena.
Doped Semiconductors Group IVA semiconductors can be “doped” by adding small amounts of impurities with more or fewer than 4 valence electrons. e.g. add.
Solar Cell Operation Key aim is to generate power by:
Principles of Radiation Detection
Lesson 17 Detectors. Introduction When radiation interacts with matter, result is the production of energetic electrons. (Neutrons lead to secondary processes.
Ionization. Measuring Ions A beam of charged particles will ionize gas. –Particle energy E –Chamber area A An applied field will cause ions and electrons.
1 Detectors RIT Course Number Lecture Single Element Detectors.
Detectors. Measuring Ions  A beam of charged particles will ionize gas. Particle energy E Chamber area A  An applied field will cause ions and electrons.
Radiation Safety level 5 Frits Pleiter 02/07/2015radiation safety - level 51.
Techniques for detecting X-rays and gamma-rays Pair production Creation of elementary particle and its antiparticle from a photon. Occurs only if enough.
Main detector types Scintillation Detector Spectrum.
Unit-II Physics of Semiconductor Devices. Formation of PN Junction and working of PN junction. Energy Diagram of PN Diode, I-V Characteristics of PN Junction,
Instruments for Radiation Detection and Measurement
Radiation Sensors Zachariadou K. | TEI of Piraeus.
Photomultiplier Tube. What is it? Extremely sensitive detector of light in the ultraviolet, visible and near infrared Multiplies the signal produced by.
Radiation Detection and Measurement II IRAD 2731.
Detectors The energy loss of particles in matter can be used detect and identify those particles. There are different types of “detectors”: - Gas-filled.
Instruments for Radiation Detection and Measurement Lab # 3 (1)
Chapter 4 Photonic Sources.
Photon detection Visible or near-visible wavelengths
Higher Physics Semiconductor Diodes. Light Emitting Diode 1  An LED is a forward biased diode  When a current flows, electron-hole pairs combine at.
References Hans Kuzmany : Solid State Spectroscopy (Springer) Chap 5 S.M. Sze: Physics of semiconductor devices (Wiley) Chap 13 PHOTODETECTORS Detection.
1 Semiconductor Detectors  It may be that when this class is taught 10 years on, we may only study semiconductor detectors  In general, silicon provides.
Lecture 5.0 Properties of Semiconductors. Importance to Silicon Chips Size of devices –Doping thickness/size –Depletion Zone Size –Electron Tunneling.
Techniques for determination of deep level trap parameters in irradiated silicon detectors AUTHOR: Irena Dolenc ADVISOR: prof. dr. Vladimir Cindro.
Incident light with an energy of hv>Eg excites an electron and causes it to jump from the valence band to the conduction band, thereby creating an electron-hole.
Tools for Nuclear & Particle Physics Experimental Background.
Interplay of polarization fields and Auger recombination in the efficiency droop of nitride light-emitting diodes APPLIED PHYSICS LETTERS 101, (2012)
NEEP 541 Ionization in Semiconductors - II Fall 2002 Jake Blanchard.
SCINTILLATION COUNTER. PRINCIPLE When light radiations strike fluorescent material it produces flashes of light called scintillations. These are detected.
SILICON DETECTORS PART I Characteristics on semiconductors.
References Hans Kuzmany : Solid State Spectroscopy (Springer) Chap 5 S.M. Sze Physics of semiconductor devices (Wiley) Chap 13 PHOTODETECTORS.
TCAD simulation of Si crystal with different clusters. Ernestas Zasinas, Rokas Bondzinskas, Juozas Vaitkus Vilnius University.
Carrier Transport Phenomena And Measurement Chapter 5 26 February 2014
ECEE 302: Electronic Devices
Medical Image Analysis Interaction of Electromagnetic Radiation with Matter in Medical Imaging Figures come from the textbook: Medical Image Analysis,
Modulators and Semiconductors ERIC MITCHELL. Acousto-Optic Modulators Based on the diffraction of light though means of sound waves travelling though.
Introduction to semiconductor technology. Outline –4 Excitation of semiconductors Optical absorption and excitation Luminescence Recombination Diffusion.
Wednesday, Oct. 18, 2006PHYS 3446, Fall 2006 Jae Yu 1 PHYS 3446 – Lecture #12 Wednesday, Oct. 18, 2006 Dr. Jae Yu 1.Particle Detection Ionization Detectors.
1 Stephen SchultzFiber Optics Fall 2005 Semiconductor Optical Detectors.
Photoluminescence and Photocurrent in a Blue LED Ben Stroup & Timothy Gfroerer, Davidson College, Davidson, NC Yong Zhang, University of North Carolina.
Optoelectronics.
Lecture 3-Building a Detector (cont’d) George K. Parks Space Sciences Laboratory UC Berkeley, Berkeley, CA.
Chapter 4 Excess Carriers in Semiconductors
Photovoltaic effect and cell principles. 1. Light absorption in materials and excess carrier generation Photon energy h = hc/ (h is the Planck constant)
Ideal Detector Fast Cheap Rugged Responds to all wavelengths of light Can distinguish different wavelengths Sensitive Low LOD.
Chapter V Radiation Detectors.
(a)luminescence (LED) (b)optical amplifiers (c)laser diodes.
3/2003 Rev 1 II.3.5 – slide 1 of 23 IAEA Post Graduate Educational Course Radiation Protection and Safe Use of Radiation Sources Session II.3.5 Part IIQuantities.
It converts light energy into electrical energy.
PN-junction diodes: Applications
PAN-2013: Radiation detectors
Chapter 4 Excess Carriers in Semiconductors
Scintillation Counter
Lecture 1—Basic Principles of Scintillation
Radiation Sensors Radiation is emission if either particles or electromagnetic rays from a source. Particles are usually nuclear particles which can be.
Radioactivity B. Sc. -III Feb Dr. Wagh G. S. M. Sc. M. Phil. Ph
Photomultiplier (PMT) Tubes
PRINCIPLE AND WORKING OF A SEMICONDUCTOR LASER
PDT 264 ELECTRONIC MATERIALS
PHYS 3446 – Lecture #16 Monday ,April 2, 2012 Dr. Brandt
PHYS 3446 – Lecture #17 Wednesday ,April 4, 2012 Dr. Brandt
Presentation transcript:

dispersive property of a G-M tube HV - + In the proportional region a G-M tube has dispersive properties tube voltage pulse size C

Solid Radiation Detectors Advantage: High density improves the efficiency of radiation absorption. Recombination is not a serious problem. Types: Scintillation detectors. Semiconductors detectors.

Excitation and Recombination in Solids energy Conduction Band Valence Band Crystal structure Electronic Band Structure electronhole defect A D

Scintillation energy Conduction Band Valence Band A D 1) Deliberately added impurities enhance trapping of charge carriers and recombination. 2) Excess energy is released in a form of visible radiation. 3) Due to the size of the band gap, the light is not absorbed in the crystal.

Properties of Selected Scintillators scintillatorDensity (g/cm 3 ) Emission (Å) Decay time (ns) Anthacene p-Terphenyl Stilbene NaI (Tl) ZnS (Ag) Sodium iodide activated with thallium may produce one electron-hole pair for every 50 eV of radiation energy. The intensity of the emitted light is proportional to the energy of the radiation.

Scintillation Detector _ – 1500 V dynodes anode output signal scintillator photocathod e Scintillation detectors are suitable for radiation spectroscopy.

Scintillation Statistics channel counts Monoenergetic radiation results in a response distributed about the most probable value. The primary reasons are: The overall response of a scintillator detector obeys Poisson statistics, convergent to normal distribution for large numbers. FWHM random nature of electron-hole pair formation variations in energy distribution between light and other recombination mechanisms uneven efficiency of reaching the PM tube nonuniform distribution of sensitivity at the photocathode and dynodes.

charge collection in semiconductor detectors V - + i Preferably each generated carrier should be collected by its attracting electrode. The signal (fraction of collected carriers) depends on both the lifetime and mobility of the carriers. The equilibrium carrier concentration should be small (low conductivity). Detectors of this type must be cooled (with LN) for proper operation.

depletion layer semiconductor detectors V - + np depletion layer Low intrinsic concentration is achieved in the depletion region. The diode conducts only after electron-hole pairs are generated by the radiation in the depletion region.

surface-barrier semiconductor detectors np Small combined thickness of the n-layer and the gold contact results in very low radiation absorption in these two regions. (Front surface detector.) V - + output signal

Multi Channel Analyzer (MCA) Multi channel analyzer counts separately (in a channel) pulses with amplitudes in a specific range. channel number of pulses When connected to a dispersive detector, each channel resisters radiation particles with energy in a corresponding energy range.

 - spectroscopy In a magnetic field, charged particle moves along a circular path determined by the magnetic field, mass and charge of the particle, and its kinetic energy (speed) G-M scaler ++