The Galactic Centre Murder Mystery

Supernova as a Murder Mystery

Rules of a

Criminal Investigation

Motive

Means

Opportunity

Rules of a

Galactic Investigation

Opportunity

Trivial for field supernovae, as coincidence probability is 1e-6

star forming regions, however...

Supernova Forensics 101

Energy = 1e51 erg

Sun's total radiative output

Most supernovae make neutron stars

Neutron stars are kicked

Supernova Shock Propagation

Ejecta dominated phase

transition when

R \propto t
M_e \approx R^3 \rho_{\rm CSM}

Sedov Taylor Phase

R \propto t^{2/5}

transition to snowplough when radiation kicks in

R \propto t^{1/4}

Neutron Star Natal Kicks

Slow and steady wins the race

The Scene of the Crime

The Victims

SGR A East

SGR X Ray Lobes

The Suspects

The Cannonball

The Magnetar

Previous Investigation

Dust Extinction

First Detection of SGR East - 1989

Supernova Remnant!

Molecular lines!

Age Determination

Molecular clouds are very dense, around 1e2/cc

Sedov Taylor age 1e4 years

t \approx \left(\frac{\rho R^5}{E}\right)

Bonus: the cannonball passes through the centre

New Evidence

Chandra density measurements,

much smaller than molecular clouds!

Magnetar spin down age 1e4 years

SGR east is dusty - should have been destroyed in ST phase

Aeolian Environment

How do supernovae evolve in such environments?

star cluster

wind

supernova explosion

Numerical Simulations

600y

1500y

6000y

9000y

Numerical Simulations

600y

1500y

6000y

9000y

Numerical Simulations

600y

1500y

6000y

9000y

Phase Diagram

Implications for Relic - Remnant Associations

X - ray lobes - magnetar

age 1e4 years

SGR East only 1500 yo

Calls into question association with the cannonball

Crime Reconstruction

SGR East and the cannonball are not associated

Conclusion

SGR East - Cannonball association

X ray lobes - Magnetar association

Made with Slides.com