Radiation Detector

Radiation Detector or particle detector is a device that measures this ionization of many types of radiation, like- beta radiation, gamma radiationsand alpha radiation with the matter. Thus, creating electrons and positively charged ions.

What is radiation detector?

Radiation Detector is an instrument used to detect or identify high-energy particles, such as those produced by nuclear decay, cosmic radiation, or reactions in a particle accelerator.

Evolution of radiation detector

Earlier, photographic plates were used to identify tracks left by nuclear interactions. Sub-nuclear particles are discovered by using cloud chambers which needed photographic recordings and a tedious measurement of tracks from the photographs.

Electronic detectors developed with the invention of the transistor. Modern detectors use calorimeters to measure the energy of the detected radiation. They may also be used to measure other attributes such as momentum, spin, charge etc. of the particles.

Type of Detectors

Scintillator

When excited by ionizing radiation, a scintillator exhibits scintillation which is nothing but the property of luminescence. When a scintillator is coupled to an electronic light sensor such as a photomultiplier tube (PMT), photodiode, or silicon photomultiplier, a scintillator detector. Scintillator-type detectors first convert light into electrical pulses. They use vacuum tubes to perform so.

Gaseous Ionization Detectors

A radiation detection instrument used in particle physics to detect the presence of ionising particles, and in radiation protection applications to measure ionizing radiation is called Gaseous ionization detectors.

Geiger Counter

Geiger-Mueller counter, commonly called the Geiger counter is the most commonly used detector. A central wire in between a gas-filled tube at high voltage is used to collect the ionization produced by incident radiation. Although it cannot distinguish between them, it can detect alpha, beta, and gamma radiation.

Types of radiations

The types of radiation detected by these detectors are Alpha, Beta and Gamma radiation.

Alpha radiation

  • Alpha particles or double ionised helium nuclei are the fast moving helium atoms.
  • They have high energy ranging in MeV.
  • They have low penetration depth; typically few cms of air or skin due to their large mass.

Beta radiation

  • They are fast-moving electrons.
  • Their energy ranges from hundreds of KeV to several MeV.
  • They have better penetration depth due to their comparatively lighter mass. Typically several feet of air, several millimetres of lighter materials.

Gamma radiation

  • They are the stream of photons.
  • Typical energy ranges from Several KeV to Several MeV.
  • They have comparatively very low mass. Thus, possess good penetration depth. Typically a few inches of lead

Practice Questions on Radiation Detectors

Q1: What is a radiation detector?

Ans: Radiation Detector is an instrument used to detect high-energy particles, such as those produced by nuclear decay, cosmic radiation, or reactions in a particle accelerator.

Q2: Name a few radiation detectors.

Ans: Few commonly known radiation detectors are scintillator, Gaseous ionization detector, Geiger-Mueller counter

Q3: Name the detector which uses the property of luminescence to detect radiations

Ans: The detector which uses the property of luminescence to detect radiations is Scintillator.

Q4: What is the function of vacuum tubes in scintillators?

Ans: Vacuum tubes in scintillators convert light into electric pulses.

Q5: What does the abbreviation PTM stand for?

Ans: PTM stands for Photomultiplier tube

Q6: What is used in the Geiger-Mueller counter to collect ionised radiations?

Ans: A central wire in between a gas-filled tube at high voltage is used to collect the ionization produced by incident radiation

Q7: Name the types of radiation the Geiger-Mueller counter detects.

Ans: the Geiger-Mueller counter detects Alpha, Beta and Gamma radiations.

Q8: Can the Geiger-Mueller counter differentiate between the types of radiation it detects?

Ans: No. the Geiger-Mueller counter detects Alpha, Beta and Gamma radiations. But it cannot distinguish between them

Q9: Name the types of radiation.

Ans: Alpha radiation, Beta radiation and Gamma radiation.

Q10: Arrange the following radiations in the ascending order of their penetration depth.

Alpha radiation, Beta radiation and Gamma radiation.

Ans: The radiations arranged according to the ascending order of their penetration depth is as follows-

Alpha radiation < Beta radiation < Gamma radiation.

Q11: Arrange the following radiations in the ascending order of their mass.

Alpha radiation, Beta radiation and Gamma radiation.

Ans: The radiations arranged according to the ascending order of their mass is as follows-

Gamma radiation < Beta radiation < Alpha radiation

Q12: What is Alpha radiation?

Ans: Alpha radiation is the stream of doubly ionised helium nuclei.

Q13: What is Beta radiation?

Ans: Beta radiation is the stream of electrons.

Q14: What is Gamma radiation?

Ans: Gamma radiation is the stream of photons.

Q15: What is the energy range of Alpha rays?

Ans: Energy of Alpha rays are in the range of MeV.

Hope you have understood about Radiation detector, their types, functions along with types of radiations and their properties.

Physics Related Topics:

Stay tuned with BYJU’S for more such interesting articles. Also, register to “BYJU’S-The Learning App” for loads of interactive, engaging physics related videos and an unlimited academic assist.


Practise This Question

__________ is the surest test for magnetism.