What is GM counter experiment?

What is GM counter experiment?

A Geiger counter (also known as a Geiger–Müller counter) is an electronic instrument used for detecting and measuring ionizing radiation. It is widely used in applications such as radiation dosimetry, radiological protection, experimental physics and the nuclear industry.

What is the role of resistance in GM counter?

One can notice a resistance. This is the same resistance, which if increased to a large value would serve the purpose of external quenching. A capacitance has been shown to be connected to the ground. This actually represents all sort of capacitance which can be generated due to the tube, wiring etc.

What are the characteristics of GM counter?

A typical Geiger-Müller (GM) Counter consists of a GM tube having a thin end-window (e.g. made of mica), a high voltage supply for the tube, a scaler to record the number of particles detected by the tube, and a timer which will stop the action of the scaler at the end of a preset interval.

What is operating voltage of GM counter?

The GM counter is a halogen quenched, end window (a thin mica window) type detector. The counter is able to detect alpha, beta, and gamma radiations. According to the manufacturer of the detector, the typical deadtime of this model is 200 µs at the recommended operating voltage of 900 V.

Which gas is used in GM counter?

A Geiger counter (Geiger-Muller tube) is a device used for the detection and measurement of all types of radiation: alpha, beta and gamma radiation. Basically it consists of a pair of electrodes surrounded by a gas. The electrodes have a high voltage across them. The gas used is usually Helium or Argon.

How do you use a GM tube?

Setting up

1. Put a radioactive source in a holder.
2. Put the Geiger-Müller tube in a stand.
3. Plug the Geiger-Müller tube into the scaler (counter) and switch on.
4. Start the voltage at about 200 volts.
5. Increase the voltage in steps of 25 volts.
6. You will find that the counts vary with voltage and then reach a plateau.

Why mica window is used in GM counter?

The metal wall of the GM tube serves as the cathode of the GM Tube. The front of the tube is a thin Mica window sealed to the metal cylinder. The thin mica window allows the passage and detection of the weak penetrating alpha particles.

What is pulse in GM counter?

Pulse height distributions of an organic GM counter were investigated. The experiment was so performed that the pulse height held a one-to-one relation with respect to the electric charge released within the counter. Some of the distributions observed showed two or three peaks.

Why is argon used in GM counter?

Argon is heavy (compared to neon or helium) which allows for more deposition of energy within the gas. This increases the detector’s efficiency. Since GM detectors are generally used for detecting gamma or beta radiation the atomic density increases the probability of interaction.

Why ethyl alcohol is used in GM counter?

It is the process to prevent the continuous discharge. Self quenching is done by vapors of ethyl alcohol because its ionization energy is less than the ionization energy of Argon atom. The G M Counter can count about 5000 particles / sec. The counting rate depends upon the death and recovery time of G M Counter.

What is the principle of GM tube?

The Geiger-Müller tube works on the same principle as the spark counter: an ionisation between two high voltage electrodes produces a pulse of current (an avalanche of charge) between the electrodes.

Which mixture is filled in GM tube?

The mixture is composed of an inert gas such as helium, argon or neon which is ionized by incident radiation, and a “quench” gas of 5–10% of an organic vapor or a halogen gas to prevent spurious pulsing by quenching the electron avalanches.