Transcript MHD accretion - wissenschaft

Cosmic Jets
as sources for
high-energetic
Neutrinos
Andreas Müller
12. 12. 2002
http://www.lsw.uni-heidelberg.de/~amueller/
Theoriegruppe
Prof. Camenzind
Landessternwarte
Königstuhl, Heidelberg
Overview
 Motivation
 The AGN paradigm
 Jet physics:
Formation, collimation, morphology
 Particle acceleration
 Jet simulations and sources
 Relativistic leptonic and hadronic Jets
 Ultra-relativistic GRB Jets
 Cosmic Rays
 Proton Blazars
 AGN neutrino flux
 Microquasars
 Microquasar neutrino fluxes
 Implications of UHE neutrino astronomy
 Surprise!
Motivation
p+p
hadrons
p+g
_
_
_
_
p+
pp0
p0
+
+
+
+
X
X
X
p
CC
CC
NC
EN > 300 MeV
photopion production
(inelastic scattering)
p+g
_
p+ + n
pp+
p0
_
_
_
m- + nm
m+ + nm
g + g
mm+
_
_
e- + ne + nm
e+ + ne + nm
escape via isospin flip
neutrinos
Cosmic neutrino sources
 Galactic sources:
Sgr A*
SN
SNRs
Microquasars 
 Extragalactic sources:

GRBs
GRBRs
AGN Jets

constraint: AMANDA threshold 50 GeV
AGN type 1
multi-wavelength spectrum
3 bumps
IR
opt
UV
Xg
AGN taxonomy
Type
Quasar
Blazar
(+ BQ)
BL Lac
Radio
Galaxy
Host Variability
all
Elliptical
Elliptical
Elliptical
Spectrum
Jets
Sources
strong
3C 273, 3C 48,
SDSS 1030+0524
(z = 6.28)
days
Optical: point source,
dichotomy in radio loud
and radio quiet,
emission lines, IR-, UVexcess, hard Xg
days
double-humped (SSA),
Xg to TeV (IC of UV),
highest Lg, small inc,
superluminal jets,
compact radio core
strong
Mrk 501, Mrk 421,
1219+285, 3C 279,
H1426+428
days
Optical variable, high Lb,
no em./abs. lines, strong
in radio, max. in LIR
no
BL Lac,
PKS 2155-304
months
Strong radio, core: flat;
jet, lobe and hot spots:
steep
strong
Cyg A, M87, M82,
3C 219
weak
NGC 1068,
NGC 4151,
MCG-6-30-15
Seyfert
Galaxy
Spiral
months
Comptonized continuum,
warm abs., em. lines,
reflection bump
LINER
all
yes
narrow emission lines,
O, S, N lines
yes
NGC 4258
ULIRG
merging
of all
types
yes
High LIR and LX, Fe K
complex,
yes
NGC 6240,
IRAS 05189-2524
Kerr black hole topology
Jet formation - theory
 Kerr black hole vital:
frame dragging in ergosphere
 ergospheric dynamo:
creates and sustains toroidal magnetic
flux and currents
 extraction of rotational energy of Kerr hole
 outgoing wind driven by MHD Alfvén waves
 reconnection: plasma decouples from
magnetic field as approaching to horizon
(restatement of No-Hair theorem)
 magnetized accretion disk: energy of
accreting plasma powers the wind
(B. Punsly, BH GHM, Springer 2001)
Jet formation - simulation
log(r) from 0.1 to 100 color-coded, arrows: velocity,
solid line: magnetic field
parameters: a = 0.95, t = 65 rS, vJet = 0.93c, g = 2.7
(Koide et al., 2001)
MHD-Jet
collimation and acceleration
 Lorentz force:
electric current
in jet plasma
 toroidal mag. field BF
 FII: acceleration
 total magnetic field B
 FI: collimation
additional dependencies:
 gas pressure
 centrifugal forces
 ambient pressure
Particle acceleration


I)
I)
Lorentz forces and gas pressure in Jets
Fermi acceleration
1st order:
relativistic shock waves propagate through
turbulent plasma accelerating charged particles
2nd order:
stochastical acceleration of particles when diffusing
through turbulent plasma

macroscopic kinetic energy of plasma transfered to
few charged particles!

shock fronts
Jets: internal shocks, bow shock
GRBs: fireball shock
SNs/SNRs: blast wave shock
(ApJS 141, 195-209, 2002, Albuquerque et al.)
Jet morphology
Jet simulation
cocoon
shocked ext. medium
bow shock
r
t = 1.64 Myr
M. Krause, LSW HD
Jet – emission knots
periodic bright knots associated with inner shocks
(rarefaction & compression)
complete linear size: 159 kpc
z = 1.112
Radio Jet – Cyg A
VLA
jet and counter-jet, core, hot spots, lobes
Synchrotron emission in radio from relativistic efalse color image: red is brightest radio, blue fainter.
D ~ 200 Mpc
X-ray Jet – Cyg A
Chandra
X-ray cavity formed by powerful jets
hot spots clearly visible in 100 kpc distance away from core
surrounding is hot cluster gas T ~ 107 to 108 K
resulting topology: prolate/cigar-shaped cavity
Relativistic hadronic
and leptonic Jets
 3 models:
BC – baryonic cold
LC – leptonic cold
LH – leptonic hot
 leptonic species: e-e+ (rel.)
 hadronic species: p, He (th.)
 Relativistic Hydrodynamics
(RHD) in 2D
 NEC SX-5 Supercomputer
 jet kinetic power:
1044 to 1047 erg/s
 typical lifetime: 10 Myr
 surprisingly similar
dynamic and morphology!
(Scheck et al., 2002)
log(r)
Relativistic hadronic and
leptonic Jets
lowest G
highest G
(Scheck et al., 2002)
Lorentz factor G after 6.3 Myr
Relativistic GRB-Jet
1.8 s after explosion
G= 10 a v = 0.995c
G
axis unit: 100 000 km
outer stellar
atmosphere
contour:
vr > 0.3c
eint > 0.05 e0
Jet:
8° opening angle
stellar surface
Jet core:
99.97% c
M.A. Aloy, E. Müller;
MPA Garching
Cosmic Rays
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


ultra high-energy CR: 1019 eV < E < 1020 eV
1st reported by Fly‘s Eye, AGASA air shower detectors
CR sources: homogeneous distributed and cosmological
candidates: GRBs (cp. BATSE @ CGRO)
AGN Jets: photo-produced p0 decay to gg
 CR sources generate UHE protons
 each has power-law differential proton spectrum:
dN/dE ~ E-a
 spectrum insensitive to source evolution with z and
cosmological parameters (H0)
 observable constraint: 1.8 < a < 2.8
 often assumed: a = 2.0
 neutrinos overtake a-value if secondary from p-p reaction!
 in p-g reactions weighting with photon power law
 WB limit: neutrino flux limited by parental proton energy!
(ApJ 425, L1-L4, 1995, Waxman; Waxman & Bahcall, 1999, 2001)
CR spectrum
ECR > 1017 eV
(astro-ph/0011524, Gaisser)
Proton Jet reactions
Proton blazar model
 non-conservative approach! (alternative to IC of accretion
disk thermal UV emission on accelerated electrons)
 proton acceleration in most powerful AGN Jets
 power law distribution: np(Ep)~Ep-s
 protons hit
- p-target yields n: Qppn(En)~ En-s neutrino production rate
 g-target yields:
• CMB: Greisen-Zatsepin-Kuz‘min cut-off (1966):
Ep < 1019 eV „intergalactic proton“
• Synchrotron spectrum with ng(Eg)~ Eg-a:
Qpgn(En)~ En-(s-a)
 protons undergo unsaturated synchrotron cascades
and emit Xg, electrons: synchrotron contributions
 drastic steepening of cascade spectrum above
Eg ~ 100 GeV: absorption of Xg by host galaxy
IR-photons from dust
 BUT: neutrinos not dampend!
(astro-ph/9306005, 9502085, 0202074, Mannheim)
Proton blazar
1218+258
 fit parameters:
q = 7°
gjet = 5
gp = 2 x 109
d=7
B=4G
(astro-ph/9502085, Mannheim)
Data:
NED
Montigny et al. 1994
Fink et al.
Whipple group
Quasar 3C273 –
predicted neutrino flux
 nm fluxes
 compared with
SNRs and Coma
galaxy cluster
 n oscillations
neglected!
(astro-ph/0202074, Hettlage & Mannheim)
Chandra homepage
Microquasars
Microquasar
Cyg X-3
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discovery in 1967 (Giacconi et al.)
companion: massive Wolf-Rayet as can be observed
from wind in I- and K-band (van Kerkwijk et al., 1992)
orbital period: 4.8 h derived from IR and X-ray flux
modulation via eclipses (Parsignault et al, 1972;
Mason et al., 1986)
TeV source!
optical observation possible (extinction in Galactic plane)
CO nature:
NS of ~ 1 M8 with 10-7 M8/yr and WR with 15 M8
(Heuvel & de Loore, 1973)
vs.
stellar BH with WR of 2.5 M8
(Vanbeveren et al., 1998; McCollough, 1999)
1st only one-sided jet (Mioduszewski et al., 1998)
Microquasar
Cyg X-3
 evolution sequence of
bipolar radio jet
 binary system:
Wolf-Rayet and NS/BH
 D = 10 kpc
 q = 14°
 b = 0.81
(Mioduszewski et al., 2001)
VLBA
Microquasar
GRS1915+105
 evolution sequence of
one-sided radio blob
 binary system:
normal star and BH
 GBHC: MBH ~ 14 M8
 D = 12.5 kpc
 q = 70°
 b = 0.92!
(Mirabel & Rodriguez, 1994)
VLA
SS 433 - data
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
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


most enigmatic and still unique object in the sky!
CO: neutron star or black hole?
companion: OB star with 20 M8
mass loss rate: 10-4 M8/yr (wind)
orbital period: 13.1 d
persistent source
1977 discovered, constellation Eagle
d = 3 kpc
i = 79°
b = 0.26 (nearly const!)
no continuous jet: bullets
slow wobbling period: 164 d
surrounded by diffuse nebular W50 (possible SNR)
jet: strong, variable Ha line emission
emission lines doubled
estimated: Ljet ~ 1039 erg/s
(ApJ 575, 378-383, 2002, Distefano, Guetta, Waxman & Levinson)
~ 20 cm
SNR W50A
SS 433
SS 433 in X-rays
T ~ 5 x 107 K
d ~ 5 x 1018 km
Chandra homepage 11.12. 2002
SS 433 - theory

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bullet ejection model
timescale: non-steady shocks in sub-Keplerian accretion flow
bullet shooting interval: 50-1000 s
donor matter rejection by centrifugal force
radiation pressure supported Keplerian disk
15 to 20% of accreted matter is outflow:
mean outflow rate: 1018 g/s
 mean accumulated bullet mass 1019 - 1021 g (moon 1021 g)
 bullet formation by shock oscillations due to inherent
unsteady accretion solutions
(astro-ph/0208148, Chakrabarti et al.)
Microquasars parameters
Sn
Ljet
i
G
 all jets resolved in radio (~280 known XRBs, ~50 radio-loud)
 SS 433 not present: more complicated model
(ApJ 575, 378-383, 2002, Distefano, Guetta, Waxman & Levinson)
Microquasars –
m event predictions
pulse
periodic
strong
persistent:
1 yr integration time Dt
(ApJ 575, 378-383, 2002, Distefano, Guetta, Waxman & Levinson)
Implications
of UHE neutrino astronomy
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


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


determination of two-component jet plasma:
fixing the ratio of leptonic to hadronic species
„Detection of n emitted by AGN would be a smoking gun
for hadron acceleration.“ (Hettlage & Mannheim)
deeper insight in Jet physics generally
better understanding of microquasar physics
detection of low-inclined radio-hidden microquasars
verification of neutrino oscillations on cosmological scales
clarification of neutrinos as Majorana particles
CR mapping
new issues for the origin of UHE cosmic rays
Most distant AGN
Chandra
SDSS quasars in 13 billion lightyears distance
emission starts as Universe was 1 billion years old!
MBH ~ 1010 M8
(Brandt et al., 2002)