Pulsar Pulsar A pulsar (from "pulse" and "-ar" as in quasar) is a highly magnetized rotating neutron star that emits a beam of electromagnetic radiation. This radiation can be observed only when the beam of emission is pointing toward Earth (much like the way a lighthouse can be seen only when the light is pointed in the direction of an observer), and is responsible for the pulsed appearance of emission. Neutron stars are very dense, and have short, regular rotational periods. This produces a very precise interval between pulses that ranges from milliseconds to seconds for an individual pulsar. Pulsars are
POlarization Emission of Millimeter Activity at the Sun of observing at 45 and 90 GHz comes from the necessity to determine the "upturn" frequency in the so-called "THz events": if the main radiation mechanism is synchrotron radiation from accelerated electrons emitting at chromospheric or coronal heights, it is expected a spectrum with a long and descending logarithmic tail towards millimeter wavelengths. In some cases this classical ("textbook") shape is broken and an "upturn" or "spectral reversion" is observed. Since the reversion or "upturn" frequency has been estimated around 50 to 100 GHz for the observed cases, the importance of POEMAS is justified. POlarization Emission of Millimeter Activity at