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Phase resolved high speed photometr y and spectrophotometr y of Pulsars with the ESO FIERA CCD Controller

What is a pulsar?
A pulsar is a highly magnetised neutron star, with a radius of 10-15 km, having somewhat greater mass than the Sun (which has a radius of approximately 1 million km). Radiation is beamed by the magnetic field and pulses of radiation are received as the beam crosses the Earth, in the same manner as the beam from a lighthouse causes flashes. Being enormous cosmic flywheels with a tick attached, they make some of the best clocks known to mankind. The interval between pulses ranges from about 4 seconds, for the slowest, to about 1.55 milliseconds for the fastest (which is spinning at 642 times per second!)

C. Cumani for the 4th ESO CCD Workshop - Garching, 15 September 1999

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Phase resolved high speed photometr y and spectrophotometr y of Pulsars with the ESO FIERA CCD Controller

Pulsars: Galactic Lighthouses

C. Cumani for the 4th ESO CCD Workshop - Garching, 15 September 1999

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Phase resolved high speed photometr y and spectrophotometr y of Pulsars with the ESO FIERA CCD Controller

The Crab Pulsar

Period: 33.493528 msec (29.8565144364 Hz) Period derivative: 36.4 nsec/day

C. Cumani for the 4th ESO CCD Workshop - Garching, 15 September 1999

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Phase resolved high speed photometr y and spectrophotometr y of Pulsars with the ESO FIERA CCD Controller

PULSE PROFILE OF THE CRAB PULSAR

Peak 1 1.2
Lead Trail

Bridge
Lead

Peak 2
Trail

1.0 Intensity (arb. units)

0.8

0.6

0.4

0.2

0.0 -0.2 0.0 0.2 Phase 0.4 0.6

C. Cumani for the 4th ESO CCD Workshop - Garching, 15 September 1999

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Phase resolved high speed photometr y and spectrophotometr y of Pulsars with the ESO FIERA CCD Controller

Phase resolved photometry Major Goals

·get a reliable mean optical flux distribution of the Crab pulsar, comparing the results with the theoretical models, ·get phase resolved spectra of the Crab pulsar, searching for phase dependent spectral features.

C. Cumani for the 4th ESO CCD Workshop - Garching, 15 September 1999

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Phase resolved high speed photometr y and spectrophotometr y of Pulsars with the ESO FIERA CCD Controller

IS OUR OBJECT BRIGHT ENOUGH ?

move charges in time

Readout

C. Cumani for the 4th ESO CCD Workshop - Garching, 15 September 1999

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Phase resolved high speed photometr y and spectrophotometr y of Pulsars with the ESO FIERA CCD Controller

IS OUR OBJECT TOO FAINT ?

shift charges in time

move charges back

C. Cumani for the 4th ESO CCD Workshop - Garching, 15 September 1999

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Phase resolved high speed photometr y and spectrophotometr y of Pulsars with the ESO FIERA CCD Controller

C. Cumani for the 4th ESO CCD Workshop - Garching, 15 September 1999

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Phase resolved high speed photometr y and spectrophotometr y of Pulsars with the ESO FIERA CCD Controller

C. Cumani for the 4th ESO CCD Workshop - Garching, 15 September 1999

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Phase resolved high speed photometr y and spectrophotometr y of Pulsars with the ESO FIERA CCD Controller

C. Cumani for the 4th ESO CCD Workshop - Garching, 15 September 1999

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