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)

Electrostatics, can whole charge of a body be transfered to other?

can whole charge of a body be transfered to other?

Shape memory alloys, SHAPE MEMORY ALLOYS: A group of metallic materials ...

SHAPE MEMORY ALLOYS: A group of metallic materials that can return to some previously defined shape or size when subjected to the appropriate thermal producer. That is to say, s

Electrostatics – two kinds of charges, Electrostatics – Two kinds of Charge...

Electrostatics – Two kinds of Charges     Introduction: If a glass rod is rubbed with silk cloth it acquires a positive charge, while silk cloth acquires an equal amo

Explain amplitude, Amplitude: The maximum displacement of a body on either...

Amplitude: The maximum displacement of a body on either side of the mean position during simple harmonic motion is known as amplitude and it is shown by x.

Determine the length required for the tube heat exchanger, A concentric tub...

A concentric tube heat exchanger is comprised of a thin wall inner tube of 25.4 mm diameter and an outer tube of 47 mm diameter. The heat exchanger is used for cooling lubricating

define electric cell, The device which changes chemical energy into electr...

The device which changes chemical energy into electrical energy is called as electric cell. Battery is a host of constant emf but not constant current.

Na+ ion is isoelectronic with, Na + ion is isoelectronic with: (1) Li ...

Na + ion is isoelectronic with: (1) Li +                     (2)  Mg +2               (3) Ca +2                                (4) Ba +2 Ans:(b) Mg +2

Determine displacement current, Show that the displacement current flowing ...

Show that the displacement current flowing between the two plaes of the capacitor is similar to the conduction current utilized in charging the capacitor.

Determine the magnitude and direction of a single force, The cantilevered b...

The cantilevered beam below is supported at O.  F1 and F2 in kN are given in P21 and P22 respectively and act on the beam as shown.  Determine the magnitude and direction of a sing

Find the temperature of the gas?, In accrued model of a rotating diatomic m...

In accrued model of a rotating diatomic molecule of (Cl 2 ), the two Cl atoms are 2.00´ 10? -10  m apart and rotate about their center of mass with angular speed w = 2.00 ´10 12 ra

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