Emission and high-energy particles in
jets, outflows and bubbles in galaxies
and beyond galaxies
Kinwah Wu
Mullard Space Science Laboratory
University College London
United Kingdom
Collabortors:
Ziri Younsi * (ITP, Frankfurt), Ignacio Ferreras (MSSL, UCL)
Idunn Jacobsen (MSSL, UCL), Aayush Saxena * (Leiden)
Sandor Kruk * (Oxford), Curtis Saxton (Technion)
Alvina On (MSSL, UCL), Steven Fuerst * (Kavli, Stanford)
Hung-Yi Pu (ASIAA), Youske Mizuno (ITP, Frankfurt)
Content
1. A phenomenological overview
2. Some simple minded physics
3. Systems that I have looked at (I) :
Emission from plasmoids ejected from black holes
Younsi & Wu (2015), MNRAS, to be submitted
4. Systems that I have looked at (II) :
UHE neutrino fluxes from various AGN populations …
Jacobsen, Wu, et al (2015), MNRAS, in press
5. Some naïve thoughts about galactic outflows:
Galactic outflows from the starburst galaxy M82
Sutton, Ferreras, Wu, et al. (2014), MNRAS, 440, 150
1. A phenomenological overview
The Hillas plot
The Lamor radius of the
particle should not exceed
the characteristic size of
its accelerator
Source phenomenology
RCW120 nebula
superbubble in the LMC
(credit: Hershel Observatory)
(credit: C. Smith [U Michigan])
Source phenomenology
large-scale galactic
winds/outflows in the
starburst galaxy M82
(credit: HST/Chandra/Spitzer)
Source phenomenology
(credit: wikipedia)
Source phenomenology
cavity/bubbles in NGC741 group
(Jetha et al. 2008)
Source phenomenology
M87
(credit: NRAO/
U Northern Iowa)
Source phenomenology
cavities/bubbles in galaxy clusters
(Doria et al. 2012)
Source phenomenology
(credit: Nature.com)
Revisiting the Hillas plot
Now, shall we look at the
Hillas plot in a slightly
different perspective?
2. Very simple-minded physics
Magnetic fields in astro-systems
magnetic field (gauss)
10-9 ?
10-6
10-3
walls? clusters
voids?
galaxies
>1026
1025
1023
103
1
stars
106
109
1012
white dwarfs
magnetars
neutron stars
1010
109
106
106
~1
1
1
1
linear size (cm)
1013
1011
mass (solar mass)
Magnetic fields in astro-systems
non-directional magnetic flux
- magnetars
- neutron stars
- white dwarfs
- solar-like stars
- galaxies
- galaxy clusters
- superclusters, filaments, voids
in co-moving frame
1028 G cm2
1021 - 1025 G cm2
1021 - 1025 G cm2
1021 - 1023 G cm2
~1041 G cm2
~1042 G cm2
???
High-energy emission
High-energy electromagnetic radiation
-
Synchrotron radiation
(inverse) Compton scattering
Bremsstrahlung radiation
Electron-positron annihilation
How about High-energy non-photonic radiation?
- Cosmic rays
- Neutrinos
It seems to need some high-energy particles.
But what? Where? How?
Transport of high-energy emission
About the delivery of the particles/radiation
- Particle number (non-)conservation
- Particle phase space conservation
About the path of delivery of the particles/radiation
- Space-time (properties)
- Electro-magnetic force (?)
Continuity equation:
Transport of high-energy emission
Continuity equation (as a Boltzmann equation):
Continuity equation (in the covariant form):
Continuity equation for free-falling particle packets:
Producing high-energy emission
Astrophysical context (macro-phenomenological physics)
- shocks in astrophysical systems
(credit: UC Berkeley)
Producing high-energy emission
Astrophysical context (macro-phenomenological physics)
- unipolar induction (?)
(credit: NRAO/AUI, MPIfR, ASC-Lebedev, Y. Y. Kovalev)
Producing high-energy emission
Astrophysical context (macro-phenomenological physics)
- alternation of magnetic field topology
(credit:NASA-GSFC)
3. Systems that I look at (I):
Emission from plasmoids ejected
from black holes
GRMHD jet
(Pu … Wu et al 2015)
Episodic outflow from a black hole
(Meyer et al. 2015)
CME-like plasmoid ejection from
accreting black holes
(Yuan, Lin, Wu, Ho 2009)
Covariant radiative transfer
Younsi & Wu (2014)
[moment expansion: Thorne (1980), Fuerst (2005), Wu et al. (2006, 2008)
Shibata et al. (2011)]
•
•
•
•
•
•
Relativistic beaming
Doppler shift
Transverse Doppler shift
Gravitational redshift
Gravitational lensing
Reference frame dragging
spin/polarisation in strong gravity
- de-Sitter precession
- Lense-Thirring precession
- spin-curvature coupling
Ray-tracing in black hole environments
Kerr black hole
Schwarzschild black hole
( Ziri Younsi, 2013, PhD thesis, UCL)
Black hole shadowing and tori around a
rotating black hole
Movies:
1. Shadow of a Kerr black hole
2. Frequency shifts on a surface of a torus around a
Kerr black hole
3. Intensity of emission from an opaque tours around
a Kerr black hole
4. Emission image of a semi-opaque torus around a
Kerr black hole
5. Emission image of an translucent torus around a
Kerr black hole
Plasmoid launched from a black hole
(Younsi & Wu 2015)
Gravitational lensing on the plasmoid
emission
Movies:
1. Plasmoid orbiting a Schwarzschild black hole
viewed at an inclination of 45 deg
2. Plasmoid orbiting a Schwarzschild black hole
viewed at an inclination of 90 deg
3. Plasmoid orbiting a Kerr black hole viewed at an
inclination of 45 deg
4. Plasmoid robiting a Kerr black hole viewed at an
inclination of 90 deg
Lightcurves of opaque plasmoids
Younsi & Wu (2015)
Lightcurves of opaque plasmoids
( Ziri Younsi, 2013, PhD thesis, UCL)
Time corrected lightcurves of an opaque
plasmoid orbiting a Schwarzschild black
hole
Younsi & Wu (2015)
Time corrected lightcurves of an opaque
plasmoid orbiting a Schwarzschild black
hole
Younsi & Wu (2015)
Time corrected lightcurves of a transparent
plasmoid orbiting a Kerr black hole
Younsi & Wu (2015)
Lightcurves of plasmoid ejection
Younsi & Wu (2015)
Lightcurves of plasmoid ejection
Younsi & Wu (2015)
3. Systems that I look at (II):
UHE neutrino fluxes from various
AGN populations derived from X-ray
surveys
AGN as UHE neutrino sources
(credit: ESO, MPIfR, APEX, NASA,
CXC)
Testing AGN as UHE neutrino sources
UHE neutrinos
jet/outflow
accretion
Gamma-ray
hadronic interaction
accretion disk
X-rays
jet astrophysics
photo-hadronic interaction
Note that
(Pakvasa 2008)
Photo-hadronic jet models
Left: Koers & Tinyakov (2008) model; Right: Becker & Biermann (2009) model
X-ray luminosity function of AGN
AGN populations
The AGN populations and their
evolution are derived from the
X-ray luminosity functions
constructed from the Chandra
(Silverman et al. 2008) and
Swift/BAT (Ajello et al. 2009)
X-ray survey data.
(Jacobsen, Wu et al. 2015)
Neutrino fluxes from various AGN
IC59: IceCube 1-year limit
(Aartsen et al.2015)
Dashed line: Best-fit IceCube
diffuse neutrino spectrum
(Aartsen et al. 2015)
(Jacobsen, Wu et al. 2015)
Neutrino fluxes from various AGN
(Jacobsen, Wu et al. 2015)
What we have found:
1. Cen A is not a typical neutrino source or not even a
source
2. X-ray and neutrino fluxes of AGN are not universally
scaled across the sub-classes
3. The jet models by Koers & Tinyakov (2008) and Becker
& Biermann (2009) overestimated the neutrino
production rate
4. Some AGN are by nature not neutrino sources
5. Neutrino generation and X-ray generation may gave
different duty cycle
6. It is a combination of the above
3. Some comments/thoughts about
galactic outflow:
Galactic outflows from the starburst
galaxy M82
The starburst galaxy M82
(credit: R. Zmaritsch and A. Gross)
Swift/UVOT observation of M82
Hutton, Ferreras, Wu et al. (2014)
Luminosity density across M82
Hutton, Ferreras, Wu et al.
(2014)
Colour difference between the galactic
disk and the wind
Hutton, Ferreras, Wu et al. (2014)
Colour difference between the galactic
disk and the wind
x=0
Mie scattering
x=-4
Rayleigh scattering
Hutton, Ferreras, Wu et al. (2014)
Size distribution of dust grain in the
galaxy wind of M82
Hutton, Ferreras, Wu et al. (2014)
Some very naïve thoughts about
galactic outflows
1. How the dust co-exist with the high-energy radiations in
the disk wind?
2. Can we use the spatial distribution of the dust
properties to infer the cosmic ray and high-energy
particle content throughout the wind cone?