Penningmittarit

Penningmittarit are scientific instruments used to measure the pressure of very low-pressure gases, typically in the range of 10⁻³ to 10⁻⁸ Pascals. The principle behind their operation involves ionizing gas particles within a magnetic field and then detecting the resulting ions. A Penning gauge consists of a vacuum chamber containing a cylindrical anode and a coaxial cathode, typically in the shape of a ring or cage. A strong magnetic field is applied radially across the chamber. Electrons emitted from the cathode are accelerated towards the anode, but their path is bent by the magnetic field, causing them to spiral. This extended path increases the probability of collisions with gas atoms, leading to ionization. The positive ions produced are attracted to the cathode, and the resulting current is proportional to the gas pressure. The magnetic field confines the electrons, enhancing ionization efficiency. Calibration is crucial for accurate pressure readings. Penningmittarit are widely used in applications requiring ultra-high vacuum, such as particle accelerators, thin-film deposition systems, and scientific research. Their main advantage lies in their sensitivity and ability to operate in a wide pressure range. However, they can be susceptible to contamination and may require periodic cleaning or recalibration.