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)

What is the velocity of the ball - magnitude and direction, A boy is standi...

A boy is standing on an elevator which is travelling downward with constant velocity of 30 meters per second.  The boy throws a ball vertically upward with velocity of 10 meter

Scattering, derive an expression for the total cross section for the scatte...

derive an expression for the total cross section for the scattering of light by a polorisable molecule in term of the incedent wave length.

Absorption and emission of A-B coefficients of einstein, Explain the absorp...

Explain the absorption and emission transitions of A and B coefficients of Einstein. Assume that N 1 and N 2 be the number of atoms per unit volume along with energy E 1 and

Dynamic Casimir effect, We can produce energy from dynamic Casimir effect?

We can produce energy from dynamic Casimir effect?

What are non ohmic and ohmic devices, What are non ohmic and ohmic devices?...

What are non ohmic and ohmic devices? Give examples The manganin wire is used in the manufacturing of standard resistances. Why?

Semiconductor materials: gallium arsenide, Energy gap: 1.4ev at room temper...

Energy gap: 1.4ev at room temperature Its charactistics are very closely related to those of germanium. This is under stable, since Gallium is the third column neighbour and a

Explain about the amplitude mode of data presentation, Explain about the am...

Explain about the amplitude mode of data presentation. The A-mode: The A-mode or the Amplitude mode of data presentation exhibits the amount of obtained ultrasonic energy li

Are fiber optics systems difficult to install, Are fiber optics systems dif...

Are fiber optics systems difficult to install? This becomes significant to establish a fair comparison with other components, in this case normal light fixtures. Fiber optics s

State ohms law, Q State Ohm's law. At a steady temperature that the st...

Q State Ohm's law. At a steady temperature that the steady current flowing through a conductor is directly proportional to the potential difference between the two ends of the

Lenz’s law , LENZ’S LAW   A change of flux in a closed circuit indu...

LENZ’S LAW   A change of flux in a closed circuit induces an emf and sets up a current.  The direction of this current is such that its magnetic field tends to oppose the c

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