Particle Outflow and Pulsar Timing Noise

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Particle Outflow and Pulsar Timing Noise
Based on Chin. Phys. Lett. Vol. 28, No. 1 (2011)
019701

• Xiong Wei Liu

Department of Astronomy, Peking University
2011-05-09
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Outline

• Background
• Our Model
• Observational Checking
• Discussion.

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Background
Theoretically, pulsars spin stably

Standard Clock

GW detection
Observationally, timing niose exist everywhere
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Background
Explainations for timing noise a.
unmodelled companions b. gravitational
waves c. free-precession of neutron star.
...
But, timing noise still cant be eliminated
completely, especially the noise in long
timescale of years.
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Our Model
Main Idea A new kind of intrinsic Timing Noise
of pulsar Theoretical Basis The Partical
outflow from a pulsar should be unstable,so is
the spin of the pulsar
(Xu Qiao 2001 ApJL. 561 L85)
is the power carried away by relativistic
particles which rise from unipolar induction, and
is the power of magnetic dipole radiation.
is the variation.
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Our Model
Observational Clue Variations of flux density
may indicate the
variations of particle outflow
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Our Model
Theoretical Result The relationship between
variations of particle outflow and Timing
Noise The longer,
the stronger the noise!
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Our Model
Simulation
Variations of particle outflow
Timing noise
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Our Model
Resemble with observations Profile feature,
range feature
and time dependence
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Observational Checking
Checking 1 Relationship between Timing Noises
and distribution of pulsars
Estimate from
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Observational Checking
Checking 2 Relationship between spin frequency,
frequency derivative and Timing Noise
Statistics from approximately 450 distinct
pulsars
Ryan M. et al. (arXiv1010.4794v1)
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Observational Checking
Checking 3 Random walks in frequency and
frequency derivativePhenomenon and the essence
Cordes Downs (1985) and DAlessandro et
al.(1995)
Ryan M. et al. (arXiv1010.4794v1)
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Discussion
New mechanism of TN The fluctuation of particle
outflow can lead to significant timing noise in
long time span of years. New Challenges
Intrinsic Timing Noise, unavoidable! The
millisecond pulsars chose to detecting GW or act
as Standard Clock, which havent found
signigicant long time span TNs, will effect by
their intrinsic TNs in longer time New Question
How to avert the bad effect of this kind of TNs?
Thank you!