Sodium iodide crystal (nai), Physics

Assignment Help:

Sodium iodide crystal (NaI)


It scintillate with good efficiency when gamma ray is absorbed, these crystals where attached directly to the PTM to detect a weak flashes of light .They where improved by adding a trace amounts of thallium(Tl)and often referred as NaI(Tl) detector. It is the most widely used detector in medicine .

A nuclear medicine scintillation detector system


1-Scince the NaI(Tl)detector is very sensitive ,it has to be well shielded from background  radiation .
2- five or more cm of lead surrounding the NaI(Tl)crystal except at the collimator .
3-The electron emitted at the photocathode of PTM produce an electrical pulse  at the output .
4-this pulse is electronically amplified at the amplifier.
5-The pulse can be directly counted by the scalar.
6-The pulse pass to the single channel  pulse height analyzer(PHA) to determine the energy of the gamma rays

It contain  an upper discriminator (it rejects the pulses larger than a chosen size)

                  lower  discriminator ( reject the pulses smaller than a chosen size)

                 window(it is the energy difference between the upper and lower limits )


Multi Chanel analyzer (MCA): it determine the pulse height distribution of all the pulses from the detector ,so it sorts the pulses according to the size.

 

12_Sodium iodide crystal (NaI).png


Related Discussions:- Sodium iodide crystal (nai)

Determine chamber reading and value to radiation exposure, 1. An ionization...

1. An ionization chamber is used on Tuesday (T=22°C, P=760mmHg) and then on Wednesday (T=25°C, P=740 mmHg) to monitor the output from an x-ray tube. If the output from the tube is

Ac output resistance in common base configuration, AC  Output  Resistance  ...

AC  Output  Resistance  in  Common  Base  Configuration Ratio  of  change  in collector-base  voltage  ( ? V CB )  to  resulting  change  in  collector  current  ( ? I C )  at

Determine the frequency spectrum of a signal, Figure shows the frequency sp...

Figure shows the frequency spectrum of a signal at 1184kHz displayed by a high-speed virtual DSO. Determine (a) The harmonic relationship among the signals marked 'o' and 'x',

Faraday constant, Faraday constant; F (M. Faraday) The electric charge...

Faraday constant; F (M. Faraday) The electric charge carried through one mole of electrons (or singly-ionized ions). This is equivalent to the product of the Avogadro constant

Scalar and vector, example of problems of vector and scalar with solution

example of problems of vector and scalar with solution

Main features of simple harmonic motion, 1. Particle travels in straight li...

1. Particle travels in straight line and the motion is periodic 2. The acceleration of particle is always proportional to the displacement from the equilibrium position and alwa

The number of unpaired electrons in the fe2+ ion is, The number of unpair...

The number of unpaired electrons in the  Fe2 +   ion is: (1) 0          (2) 4         (3) 6   (4)3 Ans: 4

Explain the focal length of the convex lens, Convex lens can be used as a m...

Convex lens can be used as a magnifying glass. When an object that is 15.0 cm from the lens has an image that is exactly 55 times the size of the object, what is the focal leng

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd