X-ray sources from laser -plasma acceleration: development ...
Recent Progress in Understanding Particle Acceleration in Astrophysical Sources: Better Observations...
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Recent Progress in Understanding Particle Acceleration in Astrophysical Sources: Better Observations + Bigger Computers = Neither Sources nor Acceleration Theories Quite What Expected …. P. Coppi, Yale With apologies to D. McCray (19 On-Demand, Ultra-Fast Reconnecti on (Mini- jets?) Convenient Charge Starvation and Current Sheet Topology – Direct Field (LINAC) Acceleration? Striped Jets And Winds? Fermi I, II, I.5? High σ /quasi- perpendicular shocks “Bad”? Kill σ! Weibel, Weibel, Weibel … Two beam instability? L AGN/GRB ~ 40 c/ω p , right? Wave Resonance & Breaking Drift, Kink Mode? Tearing Modes Radiation Reaction and Feedback/Drag? To Guide or Not Guide Field? m e vs. m p still annoying Injection Problem? Ion Ring Instability But Dad, MHD is so twentieth century … Hey, world is not 1.5D + homogenous or toroidal – 3D + Turbulence!? PIC 2.5D >1.5 but still < 3D
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Transcript of Recent Progress in Understanding Particle Acceleration in Astrophysical Sources: Better Observations...
Recent Progress in Understanding Particle Acceleration in Astrophysical Sources: Better Observations + Bigger Computers = Neither Sources nor Acceleration Theories Quite What Expected ….
P. Coppi, Yale
With apologies to D. McCray (1979)
On-Demand, Ultra-Fast Reconnection(Mini-jets?)
Convenient Charge Starvation and Current Sheet Topology – Direct Field (LINAC) Acceleration?
Striped JetsAnd Winds?
Fermi I, II, I.5?
High σ /quasi-perpendicular shocks “Bad”? Kill σ! Weibel, Weibel, Weibel …
Two beam instability?LAGN/GRB~ 40 c/ωp , right?
Wave Resonance & Breaking
Drift, Kink Mode?
Tearing Modes
Radiation Reaction and Feedback/Drag?
To Guide or Not Guide Field?
me vs. mp still annoying
Injection Problem?
Ion Ring InstabilityBut Dad, MHD is so twentieth century …
Hey, world is not 1.5D + homogenous or toroidal – 3D + Turbulence!?
PIC
2.5D >1.5 but still < 3D
Recent Progress in Understanding Particle Acceleration in Astrophysical Sources?
With apologies to D. McCray + K. Nalewajko
Dobje, dobje …
(Nature 2007)
HADRONIC
LEPTONIC
Morlino, Amato & PB 2009
RXJ1713
RX
J17
13
From P. Blasi,Brasil lectures
RXJ1713 with fermi data
1. e/p Equilibration downstream? (Morlino et al. 2009)2. Very low value of Kep at given time 3. Lines from non-equilibrium ionization ? (Ellison et al. 2010)4. What are those Fermi data points telling us?
A Puzzling situationCourtesy of S. Funk
• Most SNR detected by Fermi have steep spectra (some exceptions, such as RXJ1713)
• The predicted spectra would naively require steep diffusion D(E)~E0.7 in conflict with anisotropy measurements
Marshall et al. 2010 Pictor A rapid X-ray Variability?
Centaurus A - Chandra
Two components!
Optical polarizedSynchrotron TeV+ electrons!
Uchiyama et al. 2007
Usual Observer Questions for particle acceleration people…
• What fraction of free energy goes into protons vs. electrons?
• What are overall acceleration efficiencies?
• What’s the electron energy spectrum? [Probably there are multiple acceleration/dissipation regions – what are energy >spectra< and how do they depend on ambient parameters?]
• Marek believes jet is kinetic dominated by the end (?) – is there a preferred conversion region/location? Why? Termination shock analog
Crab? Pair loading (breeder)? Mass entrainment/baryon loading?
• How fast can you make things go? (PKS 2155 o.k.?)
• Coherent processes important or not? (High brightness temperature cores?)
• Anything interesting at boundary layer ? (cf. sheath/spine geometry? Edge brightening?)
• How much turbulence do you need/expect/what generates it?
Tammi & Duffy 2009 – no problem with “conventional” acceleration timescales in PKS 2155?
RX
TE
AS
M
months??t
192 225 monthcm!
Unlikely....
t
Problem: In "standard model," single blob would be at R 5 10c t
May-June 2002
1959 flares!(RXTE TOO)
TIMESCALES: TeV (and GeV) blazars appear to have discrete “flare” states… :
vs.
6 hr rapid variability timescalein Mrk 421??
Takahashi et al. 2001
Structure Function
2 (naive SSC)TeV xL L
(ERC, SSC,
hadronic model)
TeV xL L
Steady X-RayComponent??
N.B. June 1997 data (after main flaring) included!
The stability problem…
LinearAxes!
Key – 3 keV fluxtracks TeV fluxrelatively poorly
3C 454.3 2009 Flare – SMARTS + Fermi (Chatterjee et al.)
Oops!! -- 1ES1959 May-Aug 2002
Krawczynski et al. 2004
Multiple EmissionComponents!
In case you still thought things were simple…
Mkn 421 2002 X-ray/TeV campaign
(Dieter Horns, preliminary)
X-ray
TeV
X-ray hardness ratio (spectrum)
Counts
G. Senturk et al. 2011
Neronov et al. 2011
Markarian 501 – Just after the big multi-wavelength campaign
One zone fit to 3C 454.3 Dec 2-3 2009, Bonoli et al. X-gamma + SMARTS NIR/opt
0235 PKS 1510
PKS 2155 OJ 287
Bonning et al.
(SMARTS)
STATES!?
Different Components??
Radio Quiet vs. FSRQ Optical Variability (Bauer et al. 2009, QUEST)
Some phenomenological observations/clues/questions –
•To me, seems like we often need Emin for acceleration process?Agreed? Is it obviously γmin ~ 2σ1/2 (mp/me)? Do we actually need a large range of γ?
•Except for few cases, don’t see evidence of mono-energeticparticle distribution, i.e., no pile-up (usual result for tacc < tcool). How/why to separate emission/cooling region from acceleration region?
•Definitely multiple emission regions? One size/mechanismneed not fit all.
•Blazars more dramatic than expected. Needles/mini-jets fine, but how do we avoid GRB efficiency/cannonball problems? (Really small region has to process a lot of power.)
