How does a sodium iodide detector work?

NaI(Tl) detectors The thallium-activated sodium iodide detector, or NaI(Tl) detector, responds to the gamma ray by producing a small flash of light, or a scintillation. The scintillation occurs when scintillator electrons, excited by the energy of the photon, return to their ground state.

What type of detector is NaI?

A NaI(Tl) scintillation counter is a radiation detector which uses the effect known as scintillation. Scintillation, which occurs in the NaI(Tl) crystal, is a flash of light produced in a transparent material by the passage of a particle (an electron, an alpha particle, an ion, or a high-energy photon).

Why is sodium iodide used in scintillation detector?

Sodium Iodide. Sodium Iodide crystals have a very high luminescence (scintillation) efficiency and are available in a wide variety of sizes and geometries that makes it the most widely used scintillator. Thallium-doped Sodium Iodide produces one of the highest signals in a PMT per amount of radiation absorbed.

What is sodium iodide crystals?

Sodium iodide (chemical formula NaI) is an ionic compound formed from the chemical reaction of sodium metal and iodine. Under standard conditions, it is a white, water-soluble solid comprising a 1:1 mix of sodium cations (Na+) and iodide anions (I−) in a crystal lattice.

Which detector is useful for V ray spectroscopy?

Silicon detectors are most heavily used in charged-particle spectroscopy and are also used for Compton- recoil spectroscopy of high-energy gamma rays. Other solid-state detection media besides germanium and silicon have been applied to gamma-ray spectroscopy.

What are scintillators used for?

Scintillators are materials that are able to convert high energy radiation such as X or gamma-rays to a near visible or visible light. They are widely used as detectors in medical diagnostics, high energy physics and geophysical exploration (ref. Knoll).

How does a CZT detector work?

The CZT detector works as a semiconductor with direct conversion of gamma radiation to electric signal. This mechanism results in better spatial resolution and sensitivity, what means lower administered dose of radiopharmaceutics and/or shorter acquisition time.

What is the basic principle of scintillation detector?

The basic principle is the same for every scintillation-type detector: when radiation strikes the scintillator it causes it to give off photons of visible light (that’s the scintillation part).

How do you identify sodium iodide?

Sodium iodide is an inorganic chemical compound composed of sodium ions and iodide ions. The chemical formula of this compound is NaI. It is an ionic compound. It has a white color and is a water-soluble compound.

How do scintillators work?

In scintillation detectors the material of the detector is excited to luminescence (emission of visible or near-visible light photons) by the absorbed photons or particles. The number of photons produced is proportional to the energy of the absorbed primary photon. The light pulses are collected by a photo- cathode.

What is used to detect xrays?

In a Geiger-Müller tube, or Geiger counter, incoming X-ray photons ionize atoms in a gas-filled volume. An applied high voltage induces further ionizations from collisions between liberated electrons and neutral atoms, creating an avalanche of charged particles and a large electrical pulse that is easily detected.