blazars and neutrinos
DESCRIPTION
Blazars and Neutrinos. C. Dermer (Naval Research Laboratory) Collaborators: A. M. Atoyan (Universite de Montreal) M. Böttcher (Rice University) R. Schlickeiser (Bochum U.) Erice, June 2002 - PowerPoint PPT PresentationTRANSCRIPT
Blazars and NeutrinosBlazars and Neutrinos
C. Dermer (Naval Research Laboratory)
Collaborators: A. M. Atoyan (Universite de Montreal)M. Böttcher (Rice University)R. Schlickeiser (Bochum U.)
Erice, June 2002
“Transformation Properties of External Radiation Fields, Energy Loss Rates and Scattered Spectra, and a Model for Blazar Variability,” CD and R. Schlickeiser, ApJ, in press,
August 20th, 2002 (astro-ph/020280)
“High Energy Neutrinos from Photomeson Processes in Blazars,”A. Atoyan and CD, PRL, 87, 22, 1102 (2001)
“An Evolutionary Scenario for Blazar Evolution,” M. Böttcher and CD, ApJ, 564, 86 (2002)
“X-ray Synchrotron Spectral Hardenings from Compton and Synchrotron Losses in Extended Chandra Jets” 2002, CD and A. Atoyan, ApJ Letters, 2002, 568, L81
Outline Outline
1. Introduction1. Radio Galaxies2. Blazars3. Standard Blazar Model
2. Leptonic Models1. Radiation Processes (see Dermer and Schlickeiser 2002)2. Electron Injection and Energy Losses3. Model for Blazar Evolution
3. Hadronic Models1. Photomeson Production2. Neutrino Detection3. Neutral Beam Formation
4. Extended Jets
The Evolution of Active GalaxiesThe Evolution of Active Galaxies
The nuclear activity in a galaxy evolves in response to the changing environment, which itself imprints its presence on the spectral energy distribution of the galaxy.
External Photon field FSRQs, Intense n, beam
p + p + 0
| n + + | 2
eV Rays, cascade
FR IIs
Dilute clouds
BL Lac objects
Low luminosity
Weak jet
’sFR Is
FR I: low luminosity, twin jet sources
Cyg A
3C 2963C 465
FR II: high luminosity, lobe dominated
Radio Galaxies Radio Galaxies Fanaroff-Riley (1974) Classification Scheme
• FR I: separation between the points of peak intensity in the two lobes is smaller than half the largest size of the source
– Edge-darkened, twin jet sources
• FR II: separation between the points of peak intensity in the two lobes is greater than half the largest size of the source.
– Edge-brightened hot spots and radio lobes, classical doubles
Morphology correlates strongly with radio power at 2x1025 W/Hz at 178 MHz ( 4x1040 ergs s-1), or total radio power of 1042 ergs s-1
Optical emission lines in FR IIs brighter by an order of magnitude than in FR Is for same galaxy host brightness
3C 173.1
Blazars Blazars (see lectures by R. Sambruna for more detail)
Class of AGNs which includes optically violently variable quasars; highly polarized quasars, flat spectrum radio sources, superluminal sources
• BL Lac objects – nearly lineless (equivalent widths < 5 Å: dilute surrounding gas)
• Flat Spectrum Radio Quasars (strong emission lines: dense broad line region clouds)
Blazars: radio galaxies where jet is pointed towards us; radio galaxies = misaligned blazars
FR Is are parent population of BL Lac objects; FR IIs are parent population of FSRQs
L ~5x1048 x (f/10-9 ergs cm-2 s-1) ergs s-1L ~1045 x (f/10-10 ergs cm-2 s-1) ergs s-1
Mrk 421, z = 0.313C 279, z = 0.538
(Urry and Padovani 1995)
Blazar SED SequenceBlazar SED Sequence
Epk of synchrotron and Compton components inversely correlated with L
Sambruna et al. 1996; Fossati et al. 1998
Finding an order in the SEDs of blazars
FSRQ
BL Lac
Standard Blazar Model
Dermer and Schlickeiser 1994
-2 ≡ (sc/0.01)
•Nonthermal electron synchrotron and Compton processes
•Various sources of soft photons
•Relativistic motion accounts for lack of attenuation
Multiwavelength Blazar SpectraMultiwavelength Blazar SpectraLeptonic processes: Nonthermal synchrotron radiation
Synchrotron self-Compton radiation,
Accretion disk radiation
Disk radiation scattered by broad-line clouds
Blazar VariabilityBlazar Variability
Location of gamma-ray production site can be measured with GLAST
Blazar Sequence ComparisonBlazar Sequence Comparison
•Evolution from FSRQ to BL Lac Objects in terms of a reduction of fuel from surrounding gas and dust
FSRQ
BL Lac
What about Nonthermal Protons and Ions?What about Nonthermal Protons and Ions?
Nonthermal particles;Intense photon fields
Importance of external radiation field for photomeson production in FSRQs
Strong photomeson production
0, pnp
B and Photomeson NeutrinoProduction Calculations
)
640
K1 0.2 = 380b
K2 0.5-0.6 = 120 b
Beq
Bob
Tavecchio + 1998;Atoyan and Dermer 2001
NonthermalProton Spectrum
eVE
rGBcmr
N
sergsL
p
bL
ppp
p
p
1918
max6
2
1448
1010
)(/)101.3(
)(
102
• Nonthermal proton power corresponds to average –ray luminosity measured from 3C 279
• Unlikely to produce UHECRs in the inner jets of blazars
Proton power based on 3-week average spectral fluxes from 3C 279 in 1996 (Wehrle et al. 1998)
Photomeson production energy-loss timescale
Different Doppler factors
= 15 = 10
= 7
• photomeson energy-loss timescales in observer frame for properties derived from 3-week average spectral fluxes from 3C 279 in 1996 (Wehrle et al. 1998)
• tvar = 1 day
• compare case with no external field
Atoyan and Dermer 2001
Evolution of the proton distribution
= 7 1 day3 day,10 day,21 day,30 day
Energy Distributions of Relativistic ProtonsDifferent Doppler factors
= 15
= 10
= 7Proton distribution after 3 weeks, with and without external field
Dots: no neutron escape
Nonthermal proton accumulation
np
Neutrino and -Ray FluencesDifferent Doppler factors
= 15
= 10
= 7 • Neutrino and -ray fluences from 3C 279 based on 3-week average spectral fluxes observed in 1996 (Wehrle et al. 1998),
with tvar = 1 day
Evolution of the Neutrino Flux
= 7
1 day3 day,10 day,21 day,30 day
3-week average Neutrino FluxesDifferent Doppler factors
• Neutrino fluxes from 3C 279 based on 3-week average spectral fluxes observed in 1996 (Wehrle +
1998), with tvar = 1 day
• Compare average -ray fluxes observed during this time:
5x10-10 ergs cm-2 s-1
• ~ 10% efficiency in neutrinos compared to rays
• what is kpe?
= 15
= 10 = 7
Astronomy
High Energy Neutrino Physics
X-rays from the Outer Jet
Sambruna et al. 2001Wilson et al. 2000Wilson et al. 2001
Schwartz et al. 2000; Chartas et al. 2000
Pictor A Cygnus A
3C 273
PKS 0637-752
Pair halos(Aharonian, Coppi, and Völk 1994
Neutrino detection with km2 exposure
Three week average
P
100 TeV
Gaisser, Halzen, and Stanev 1995
-4
7
10
15
10
15
10No neutron escape
No external radiation field
Neutrino detection with km2 exposure
Parameters derived from 2 day flare of 3C 279 in 1996; tvar = 1 day
7
10
15
10
15
10No neutron escape
No external radiation field
Predict FSRQ sources of high energy neutrinos
Electromagnetic Cascade
n,
Hot Spot
Photons with energies > 100 TeV are attenuated by CMB and DIIRF background and materialize into e+-e- pairs and produces electromagnetic cascade
Neutron beam more highly directed than jet plasma; pre-accelerates IGM in FSRQs;Difference between FR I and FR II galaxies
Some beam energy is reprocessed into rays through Compton scattering, forming pair halos around radio-loud AGN (Aharonian, Coppi, & Völk 1994)
Rest of beam energy emerges as X-ray synchrotron jet
Larger magnetic field in hot spot reprocesses directed electron-positron beam energy into synchrotron radiation
?
Blazar energy in 30-100 TeV rangeinjected into IGM
IGMn,
Inner JetSMBH
Evolution of Luminous and Active Galaxies
Evolution of Blazars
will be tested by Neutrino Telescopes(Neutrinos from FSRQs rather than BL Lacs)
and Gamma Ray Telescopes (-ray halos around FR II galaxies, but not around FR I
galaxies;
Statistics of BL Lacs and FSRQs)
Radio Jet Formation Scenario
Galaxy EvolutionGalaxy Evolution
• Dark matter halos collapse from initial spectrum of density fluctuations• Press-Schechter formalism for collapse on different mass scales• Hierarchical structure formation (bottom-up) • Cluster accretion and subcluster interactions• Infrared luminous galaxies• Galaxy mergers and fueling: evolution of active galaxies• Black Hole/Jet Physics• Formation of jets in FR II and FRI radio galaxies: importance of neutral beams• Extended X-ray emission from jet sources• Neutrino and -ray test
Sensitivity of High Energy TelescopesSensitivity of High Energy Telescopes
Chandra
ASCAHESS