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Applications of Scintillation for Compact Binaries:

The Double Pulsar

Diego Montalvo

With the great help of Marten van Kerkwijk, Ue-Li Pen, Daniel Baker, Ashley Stock, Jacob Askew

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Compact Binaries

Hu, et al., 2020

Image: Space Australia

Aid in the MOI uncertainty measurement; current uncertainties with Galactic measurements state 17% for d = 0.4kpc, and 43% for d = 1.6kpc, with possibilities to go down to 11%.

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Brisken, et al., 2010

Reardon, et al., 2020

Baker, et al., 2022

Advancements in the scintillometry toolkit

Reardon, et al., 2024

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An scintillation arc attempt

 

 

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Constructing the effective motion

Pulsar orbital motion

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Constructing the effective motion

System schematic (not to scale)

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Constructing the effective motion

System schematic (not to scale)

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Constructing the effective motion

System schematic (not to scale)

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Constructing the effective motion

System schematic (not to scale)

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Constructing a new dynamic spectrum

 

 

 

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Constructing a new dynamic spectrum

Askew J., et al., 2024

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Methods for constructing an effective motion curve

  • Secondary spectrum subtraction

A bad choice of orbital parameters:

A better choice for orbital parameters:

A better choice of orbital parameters:

A bad choice of orbital parameters:

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Some results

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A second screen!

MJD 60397

MJD 60455

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A second screen!

An approach

Scaled by screen 1 (tall one)

Scaled by screen 2 (lower one)

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A curvature-reliant measurement

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A curvature-reliant measurement

Screen 1

Screen 2

Warning!! We do not trust these values yet!

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A coherent method with phases

Simulation for a dominant image (from a 1D screen)

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Conclusions:

Thank you!

- We have developed a set of scintillation techniques to study arcs and infer physical parameters from fast binaries.

- We found evidence for a second scintillation screen for the double pulsar.

- We have applied these methods to the two screens of the double pulsar with improved precision (were we hope to improve the confidence on the inferred parameters). As well as applying a similar analysis to J1946+2052

J1946+2052

J0737-3039

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EXTRA SLIDES

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MJD 59943

Simulation with two screens

Resampled under the tall screen (blue)

Bright but short second screen, hidden at low delays (orange)

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