In this tutorial we will recover the spin period of the Crab nebula pulsar. A pulsar is a highly magnetized rotating compact star (a neutron star or a white dwarf) that emits beams of electromagnetic radiation out of its magnetic poles. This radiation can be observed only when a beam of emission is pointing toward Earth, 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.

We will use a dataset of 626,387 observations (energy levels) obtained with the XMM-Newton telescope by Dr. Fred Jansen (European Space Agency ESA) on 2006, Feb 25th. XMM-Newton is an X-ray space observatory launched by the ESA in December 1999 on an Ariane 5 rocket. It is a/o tasked with investigating interstellar X-ray sources.

We extracted the Crab nebula pulsar dataset from Dr. Guillaume Belanger's (ESA) Github page.  The observations are expressed in seconds (X Axis) vs Corrected Energy (Y Axis). As Peranso uses days (or hours) for the X Axis, we have converted the values to (Julian) days, before importing the dataset in Peranso

We know from literature that the Crab nebula pulsar spins (rotates) at approx. 30 Hz = 30 cycles per second (c/s). In the above cited Github page, Dr. Belanger finds a spin period of 29.7735689 c/s. Converted to cycles per hour, this corresponds with 107,184.8480 c/h.

As this is the largest dataset used in our Tutorials, the spin period analysis will clearly require a lot of compute power from your PC. 

This tutorial uses observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA.