Almog Yalinewich - Pulsar Coffee 12.6.20
Plan of the Talk:
Mini EMP from SGR 1806-20
on 21:30:26.5 UT, Dec 27, 2004
10% of the magnetic energy
400-800 MHz band
two 5ms bursts separated by 30ms pause
8 second delay after x ray
Fluence: 6 MJy ms
Fluence 6.8e−7 erg /cm^2
Energy 8e38 erg
Peak photon energy 70 keV
Magnetars are terribly inefficient at producing FRBs
Luminosity 5e40 erg/s
Mature magnetar originally detected in X ray by swift
Distance 6.6kpc
Age 1.6e4
Precision 10%
E oscillating, B static, both mutually orthogonal
Is the radio transient part of the population of previous FRBs?
Energy budget
Time averaged radio luminosity
Lifetime
No galactic magnetar is as potent as cosmic FRB sources
Exotic formation channel? (SLSNe, AIC)
otherwise burst is masked
Time changing linear polarisation angle
Simultaneous x ray and radio
Blackbody x ray spectrum
Comparable energy in X rays and radio
curvature radiation
Outflow interaction with the magnetosphere
Spindown models
Similar X -ray and radio energies
changes in period?
Stimulated Emission
Antenna emission
Relativistic cyclotron frequency
The reason such low frequencies were never observed is that they are up - scattered by induced Compton
Incoherent synchrotron
At the nebula - remnant interface
Lower radio to X-ray luminosity ratio compared to FRB200428
Collision with previously ejected material
can be made to fit X-ray to luminosity ratio
Association of SGR1935-20 with other FRBs is inconclusive
Magnetar models where the emissions happens inside the magnetosphere produce a radio to X-ray luminosity ratio that is too high
Shock wave at the nebula - remnant boundary produce a ratio that is too small
Internal shocks can reproduce this ratio and also the peak X-ray photon energy
questions?