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)

Explain displacement, Explain displacement x(t) is known as displaceme...

Explain displacement x(t) is known as displacement and it denotes the position of a body at time. If the displacement is positive then that body is to the right of the chosen

Using the goal seek tool determine the velocity, Using formulas, absolute a...

Using formulas, absolute addresses, and x-y plot: Supplies are dropped from an airplane to land at a certain point.  The velocity of the package at release from the airplane is

Detection (receiver), Detection (Receiver): The antenna receiver these mod...

Detection (Receiver): The antenna receiver these modulated waves from different transmitting stations. Channel selector selects the desired signals. The selected signals are am

Determine the current taken by the capacitor, A motor has an output of 4.8k...

A motor has an output of 4.8kW, an efficiency of 80% and a power factor of 0.625 lagging when operated from a 240V, 50Hz supply. It is needed to improve the power factor to 0.9

Explain electric lawn-mower, Explain electric lawn-mower A television ...

Explain electric lawn-mower A television set having a power rating of 120W and electric lawn-mower of power rating 1 kW are both linked to a 240V supply. If 3A, 5A and 10A

What do the negative sign tell you about the image, Q. What do the negative...

Q. What do the negative sign tell you about the image? A single lens is utilized to form an image of an actual physical object. You compute the image position i and find that

What is zener breakdown, When reverse bias is enhanced the electric field a...

When reverse bias is enhanced the electric field at the junction also enhances. At some stage the electric field becomes so high that it breaks the covalent bonds building electron

Precaution to minimize radiation danger, Precaution to minimize Radiation D...

Precaution to minimize Radiation Danger: 1. One should keep safe distance away from radiation emitting source. 2. The radiation from the reactor are shielded by thick concr

Communication physics, In a transmitter the final stage class C amplified ...

In a transmitter the final stage class C amplified with 18V DC supply calculate what equivalent Road the transistor to an antenna with 50ohm load impedance design and draw an L n

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