magneticsector

Magnetic sector refers to a component within certain scientific instruments, particularly mass spectrometers, that uses magnetic fields to separate charged particles based on their momentum. This separation is achieved because the magnetic force exerted on a charged particle is proportional to its momentum and velocity, and inversely proportional to the radius of its curved path. As particles with different momenta travel through a uniform magnetic field, they will follow paths of different radii.

In a typical magnetic sector mass spectrometer, ions are accelerated to a known kinetic energy and then enter a magnetic field. The magnetic field bends the path of the ions. Lighter ions or ions with higher velocities will be deflected more than heavier ions or ions with lower velocities, assuming they have the same charge. This differential deflection allows for the spatial separation of ions based on their mass-to-charge ratio. After being separated by the magnetic field, the ions are detected.

Magnetic sectors were among the earliest designs for mass analyzers and are still utilized in various scientific applications. They are known for their high resolution and accuracy. The principle of magnetic deflection is fundamental to understanding how mass spectrometers differentiate between different isotopes of elements or identify different molecular fragments. The strength of the magnetic field and the geometry of the sector are critical parameters in determining the instrument's performance.