pfrommer: particle acceleration and radiation from galaxy clusters

8/14/2019 Pfrommer: Particle Acceleration and Radiation from Galaxy Clusters

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Cosmological simulations with cosmic rays

Gamma-ray emission from clusters

Diffuse radio emission in clusters

Particle Acceleration and Radiationfrom Galaxy Clusters

Christoph Pfrommer1,2

in collaboration with

Anders Pinzke3, Torsten Enlin4, Volker Springel4,Nick Battaglia1, Jon Sievers1, Dick Bond1

1

Canadian Institute for Theoretical Astrophysics, Canada2Kavli Institute for Theoretical Physics, Santa Barbara

3Stockholm University, Sweden4Max-Planck Institute for Astrophysics, Germany

2 Oct 2009 / KITP Conference on Astrophysical Plasmas

Christoph Pfrommer Particle Acceleration and Radiation from Galaxy Clusters
http://goforward/http://find/http://goback/


2/54




Outline

1 Cosmological simulations with cosmic rays

Motivation and observations

Cosmological galaxy cluster simulations

Non-thermal processes in clusters

2 Gamma-ray emission from clusters

Spectra and morphology

Predictions for Fermi and IACTs

MAGIC observations of Perseus

3 Diffuse radio emission in clustersThe cosmic magnetized web

Properties of cluster magnetic fields

Cluster turbulence

http://find/http://goback/


3/54







Outline

1 Cosmological simulations with cosmic rays




2 Gamma-ray emission from clustersSpectra and morphology





Cluster turbulence



4/54







How universal is diffusive shock acceleration (DSA)?What can galaxy clusters teach us about the process of shock acceleration?

Cosmological structure formation shock physics complementary tointerplanetary and SNR shocks:

probing unique regions of DSA parameter space: Mach numbers M 2 . . .10 with infinitely extended (Mpc)and lasting (Gyr) shocks (observationally accessible @ z = 0) plasma- factors of 102 . . .105

origin and evolution of large scale magnetic fields and nature ofturbulent models in a cleaner environment (1-phase medium)

consistent picture of non-thermal processes in galaxy clusters(radio, soft/hard X-ray, -ray emission) illuminating the process of structure formation history of individual clusters: cluster archeology



5/54







Shocks in galaxy clusters

1E 0657-56 (Bullet cluster)

(X-ray: NASA/CXC/CfA/M.Markevitch et al.; Optical:

NASA/STScI; Magellan/U.Arizona/D.Clowe et al.; Lensing:

NASA/STScI; ESO WFI; Magellan/U.Arizona/D.Clowe et al.)

Abell 3667

(radio: Johnston-Hollitt. X-ray: ROSAT/PSPC.)


C l i l i l i i h i M i i d b i


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Radiative simulations with GADGET flowchart

CP, Enlin, Springel (2008)


C l i l i l ti ith i M ti ti d b ti


7/54







Radiative simulations with cosmic ray (CR) physics

CP, Enlin, Springel (2008)


Cosmological simulations with cosmic rays Motivation and observations


8/54







Diffusive shock acceleration Fermi 1 mechanism (1)

Spectral index depends on the Mach number of the shock,

M = shock/cs:

log p

strong shock

10 GeV

weak shock

keV

log f




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Diffusive shock acceleration efficiency (2)

CR proton energy injection efficiency, inj = CR/diss:

2.0 2.5 3.0 3.5 4.0

0.001

0.010

0.100

1.000

CR

energ

yinjectionefficiencyinj

inj

Mach number M

kT2 = 10 keVkT2 = 0.3 keVkT2 = 0.01 keV

3 5 11/3 3




10/54







Radiative cool core cluster simulation: gas density

10-1

100

101

102

-15 -10 -5 0 5 1 0 15-15

-10

-5

0

5

10

15

-15 -10 -5 0 5 10 15

x [ h-1 Mpc ]

-15

-10

-5

0

5

10

15

y

[h-1Mpc]

-15 -10 -5 0 5 1 0 15-15

-10

-5

0

5

10

15

1+

gas




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Mass weighted temperature

105

106

107

108

-15 -10 -5 0 5 1 0 15-15

-10

-5

0

5

10

15

-15 -10 -5 0 5 10 15

x [ h-1 Mpc ]

-15

-10

-5

0

5

10

15

y[h-1Mpc]

-15 -10 -5 0 5 1 0 15-15

-10

-5

0

5

10

15

T

gas

/gas

[K]




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Mach number distribution weighted by diss

1

10

-15 -10 -5 0 5 1 0 15-15

-10

-5

0

5

10

15

-15 -10 -5 0 5 10 15

x [ h-1 Mpc ]

-15

-10

-5

0

5

10

15

y

[h-1Mpc]

-15 -10 -5 0 5 1 0 15-15

-10

-5

0

5

10

15

M

diss/

diss




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g y





Mach number distribution weighted by CR,inj

1

10

-15 -10 -5 0 5 1 0 15-15

-10

-5

0

5

10

15

-15 -10 -5 0 5 10 15

x [ h-1 Mpc ]

-15

-10

-5

0

5

10

15

y

[h-1Mpc]

-15 -10 -5 0 5 1 0 15-15

-10

-5

0

5

10

15

M

CR,

inj

/CR

,inj




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g y





CR pressure PCR

10-17

10-16

10-15

10-14

10-13

10-12

-15 -10 -5 0 5 1 0 15-15

-10

-5

0

5

10

15

-15 -10 -5 0 5 10 15

x [ h-1 Mpc ]

-15

-10

-5

0

5

10

15

y[h-1Mpc]

-15 -10 -5 0 5 1 0 15-15

-10

-5

0

5

10

15

PCRgas

/gas

[erg

cm3h2

]




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Relative CR pressure PCR/Ptotal

10-2

10-1

100

-15 -10 -5 0 5 1 0 15-15

-10

-5

0

5

10

15

-15 -10 -5 0 5 10 15

x [ h-1 Mpc ]

-15

-10

-5

0

5

10

15

y[h-1Mpc]

-15 -10 -5 0 5 1 0 15-15

-10

-5

0

5

10

15

PCR

/Ptotgas

/gas




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Multi messenger approach for non-thermal processes



G i i f l


C l i l l l i l i


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G i i f l t


C l i l l l t i l ti


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Gamma ray emission from clusters




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Non-thermal emission from clustersExploring the memory of structure formation

primary, shock-accelerated CR electrons resemble currentaccretion and merging shock waves

CR protons/hadronically produced CR electrons trace the timeintegrated non-equilibrium activities of clusters that is modulated

by the recent dynamical activities

How can we read out this information about non-thermal populations? new era of multi-frequency experiments, e.g.:

GMRT, LOFAR, MWA, LWA, SKA: interferometric array of radio

telescopes at low frequencies ( (15 240) MHz)

Simbol-X/NuSTAR: future hard X-ray satellites (E (1100) keV)

Fermi -ray space telescope (E (0.1 300) GeV)

Imaging air Cerenkov telescopes (E (0.1 100) TeV)


Cosmological simulations with cosmic raysGamma-ray emission from clusters

Motivation and observationsCosmological galaxy cluster simulations


21/54





Non-thermal emission from clustersExploring the memory of structure formation

primary, shock-accelerated CR electrons resemble currentaccretion and merging shock waves

CR protons/hadronically produced CR electrons trace the timeintegrated non-equilibrium activities of clusters that is modulated

by the recent dynamical activities

How can we read out this information about non-thermal populations? new era of multi-frequency experiments, e.g.:

GMRT, LOFAR, MWA, LWA, SKA: interferometric array of radio

telescopes at low frequencies ( (15 240) MHz)

Simbol-X/NuSTAR: future hard X-ray satellites (E (1100) keV)

Fermi -ray space telescope (E (0.1 300) GeV)

Imaging air Cerenkov telescopes (E (0.1 100) TeV)



Spectra and morphologyPredictions for Fermi and IACTs


22/54



Predictions for Fermi and IACT s


Outline

1 Cosmological simulations with cosmic raysMotivation and observations








Cluster turbulence





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Predictions for Fermi and IACT s


CR proton and -ray spectrum (Pinzke & CP 2009)

10-2 100 102 104 106 108

p = Pp / (mp c)

10-3

10-2

10-1

1.0

f(p)p

2

10-2

100

102

104

106

108

1010

E[ GeV ]

10-12

10-11

10-10

10-9

F

(>E

)E

[GeVcm

2s

1]

sIC

pIC

Pion decay





24/54

y

Diffuse radio emission in clusters MAGIC observations of Perseus

Hadronic -ray emission, E > 100 GeV

10-12

10-11

10-10

10-9

10-8

S

(E

>100GeV)[ph

cm-2s

-1]

-5 0 5

-5

0

5

-8 -6 -4 -2 0 2 4 6 8

x[Mpc ]

-8

-6

-4

-2

0

2

4

6

8

y[Mpc]

-8 -6 -4 -2 0 2 4 6 8-8

-6

-4

-2

0

2

4

6

8





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y


Inverse Compton emission, EIC > 100 GeV

10-12

10-11

10-10

10-9

10-8

SIC,total

(E

>100GeV)[phcm-2s

-1]

-5 0 5

-5

0

5

-8 -6 -4 -2 0 2 4 6 8

x[Mpc ]

-8

-6

-4

-2

0

2

4

6

8

y[Mpc]

-8 -6 -4 -2 0 2 4 6 8-8

-6

-4

-2

0

2

4

6

8





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Total -ray emission, E > 100 GeV

10-12

10-11

10-10

10-9

10-8

Stotal

(E

>100GeV)[phcm-2s

-1]

-5 0 5

-5

0

5

-8 -6 -4 -2 0 2 4 6 8

x[Mpc ]

-8

-6

-4

-2

0

2

4

6

8

y[Mpc]

-8 -6 -4 -2 0 2 4 6 8-8

-6

-4

-2

0

2

4

6

8





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Correlation between thermal X-ray and -ray emission

10-3

10-2

10-1

100

correlationspace

density[arbitraryunits]

10-10 10-9 10-8 10-7 10-6 10-5 10-4 10-310-10

10-9

10-8

10-7

10-6

10-5

10-4

10-10 10-9 10-8 10-7 10-6 10-5 10-4 10-3

SX

[ ergcm-2 s-1h703]

10-10

10-9

10-8

10-7

10-6

10-5

10-4

S

(>100Me

V)[

cm-s-h70]

10-10 10-9 10-8 10-7 10-6 10-5 10-4 10-310-10

10-9

10-8

10-7

10-6

10-5

10-4

merger, 10

15

h

-1

MO

:

Correlation with pion decay/sec. IC emission,

X-ray and secondary emission n2

(CP, Enlin, Springel 2008)

10-3

10-2

10-1

100

correlationspace

density[arbitraryunits]

10-10 10-9 10-8 10-7 10-6 10-5 10-4 10-310-10

10-9

10-8

10-7

10-6

10-5

10-4

10-10 10-9 10-8 10-7 10-6 10-5 10-4 10-3

SX [ ergcm-2 s-1h70

3]

10-10

10-9

10-8

10-7

10-6

10-5

10-4

S

(>100MeV)[

cm-2s

-1h70

2]

10-10 10-9 10-8 10-7 10-6 10-5 10-4 10-310-10

10-9

10-8

10-7

10-6

10-5

10-4

merger, 1015

h-1

MO :

Correlation with primary IC emission,

correlation space substructure

oblique curved shocks; B-generation!



Diff di i i i l


MAGIC b i f P


28/54


Photon index - variations on large scales

0.80

0.87

0.93

1.00

1.07

1.13

1.20

(100M

eV,1GeV)

-5 0 5

-5

0

5

-8 -6 -4 -2 0 2 4 6 800000000

x [Mpc ]

-8

-6

-4

-2

0

2

4

6

8

00000000

y[

Mpc]

-8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8-8

-7

-6

-5

-4

-3

-2

-1

0

1

2

3

4

5

6

7

8-8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8

-8

-7

-6

-5

-4

-3

-2

-1

0

1

2

3

4

5

6

7

8

1 GeV100 MeV

(Fermi): pion bump (center)

transition to pIC (strong accretion shocks)

1.00

1.10

1.20

1.30

1.40

1.50

1.60

(100G

eV,

1TeV)

-5 0 5

-5

0

5

-8 -6 -4 -2 0 2 4 6 800000000

x [Mpc ]

-8

-6

-4

-2

0

2

4

6

8

00000000

y[Mpc]

-8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8-8

-7

-6

-5

-4

-3

-2

-1

0

1

2

3

4

5

6

7

8-8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8

-8

-7

-6

-5

-4

-3

-2

-1

0

1

2

3

4

5

6

7

8

1 TeV100 GeV

(IACTs): pion-decay (center)

pIC (accretion shocks, cutoff Emax)



Diff di i i i l t


MAGIC b ti f P


29/54


Universal CR spectrum in clusters

Fermi: ~ 2.5

IACT: ~ 2.2p

p

10-4

10-2

100

102

104

106

108

1010

p

0.001

0.01

0.1

1

10

Normalized CR spectrum shows universal concave shape governed by

hierarchical structure formation and the implied distribution of Mach numbers

that a fluid element had to pass through in cosmic history (Pinzke & CP 2009).







30/54


An analytic model for the cluster -ray emissionComparison: simulation vs. analytic model, Mvir (10

14, 1015)M

10-32

10-31

10-30

10-29

10-28

10-27

(r,

E

=100M

eV)[phcm-3s

-1]

g72a

g914

pion decay profile:

simulation

analytic model

0.01 0.10 1.00R / Rvir

-0.4-0.20.00.20.4

/

Spatial -ray emission profile

10-13

10-12

10-11

10-10

10-9

g72a

g914

pion decay spectrum:

simulation

analytic model

10-2 100 102 104 106 108 1010

E[ GeV ]

-0.4-0.20.00.20.4

F

(>E

)E

[GeVcm

2s

1]

F

/F

Pion decay spectrum







31/54


Gamma-ray scaling relations

1014 1015

Mvir [ MO ]

1041

1042

1043

1044

1045

1046

L

(E

>100MeV)[phs-

1]

total -ray emission, excl. galaxies, R


32/54


Predicted cluster sample for Fermiand IACTs

0 20 40 60 80 100

10-10

10-9

10-8

0 20 40 60 80 100

10-13

10-12

10-10

10-9

10-8

OPHIU

CHU

COMA

FORN

AX

A3627

PERS

EUS

A352

6

A1060

3C129

AWM7

M49

A075

4

CRs with galaxiesCRs witout galaxies

F

(E

>100GeV)

F

(E

>100MeV)

extended HIFLUGCS cluster ID

black: optimistic model, including galactic point sources that bias -ray flux

high; red: realistic model, excluding galactic point sources







33/54


Predicted cluster sample for Fermi brightest objects

10-10

10-9

10-8

0

2

4

6

8

10

12

14

excl. galaxies

Ophiuch

us

Com

aA36

27,Perseus

Fo

rnax

A36

26,A10

60

3C

129

Nclusters

F [phcm2 s1]







34/54









35/54

Upper limit on the TeV -ray emission from Perseus

100 1000

E[GeV]

10-14

10-13

10-12

10-11

10-10

F

(>E

)[phs-1c

m-2]

radiative physics w/ gal. x 3.5radiative physics w/ gal.

radiative physics w/o gal.

F, min (B0 = 10 G, B < th / 3)

The MAGIC Collaboration: Aleksic et al. & CP et al. 2009







36/54

Results from the Perseus observation by MAGIC

assuming f p with = 2.1, PCR Pth:ECR < 0.017Eth most stringent constraint on CR pressure!

upper limits consistent with cosmological simulations:Fupper limits(100GeV) = 3.5 Fsim (optimistic model)

simulation modeling of pressure constraint yieldsPCR/Pth < 0.07 (0.14) for the core (entire cluster)

3 physical effects that resolve the apparent discrepancy:

concave curvature hides CR pressure at GeV energies

galactic point sources bias -ray flux high and pressurelimits low (partly physical)relative CR pressure increases towards the outer parts(adiabatic compression and softer equation of state of CRs)







37/54

Minimum -ray flux in the hadronic model

0.1 1.0 10.0

10-3

10-2

10-1

100

10

1

B[G]

j,IC(B)/j

,IC(BCMB)

j(B)/j(BCMB)

jIC(B)/jIC(BCMB)

For j(B) : = 1

= 1.15

= 1.30

= 1.45

Synchrotron emissivity of high-

energy, steady state electron

distribution is independent of the

magnetic field for B BCMB!

Synchrotron luminosity:

L = A

dV nCRngas

(+1)/2B

CMB + B

A dV nCRngas (B CMB)-ray luminosity:

L = A

dV nCRngas

minimum -ray flux:

F,min =AA

L4D2







38/54

Minimum -ray flux in the hadronic model

0.1 1.0 10.0

10-3

10-2

10-1

100

101

B[G]

j,IC(B)/j

,IC(BCMB)

j(B)/j(BCMB)

jIC(B)/jIC(BCMB)

For j(B) : = 1

= 1.15

= 1.30

= 1.45

Synchrotron emissivity of high-

energy, steady state electron

distribution is independent of the

magnetic field for B BCMB!

Synchrotron luminosity:

L = A

dV nCRngas

(+1)/2B

CMB + B

A dV nCRngas (B CMB)-ray luminosity:

L = A

dV nCRngas

minimum -ray flux:

F,min =AA

L4D2







39/54

Minimum -ray flux in the hadronic model: Fermi

Minimum -ray flux (E > 100 MeV) for the Coma cluster:

CR spectral index 2.0 2.3 2.6 2.9

F [1010 phcm2s1] 0.8 1.6 3.4 7.1

These limits can be made even tighter when considering energyconstraints, PB < Pgas/30 and B-fields derived from Faradayrotation studies, B0 = 3 G:F,COMA (1.1 . . .1.5) 10

9cm2s1 FFermi, 2yr

Non-detection by Fermi seriously challenges the hadronicmodel.

Potential of measuring the CR acceleration efficiency fordiffusive shock acceleration.







40/54

Minimum -ray flux in the hadronic model: IACTs

Minimum -ray flux (E > 100 GeV) for the Coma cluster:

CR spectral index 2.0 2.3 2.6 2.9

F [1014 phcm2s1] 20.2 7.6 2.9 1.1

These limits can be made even tighter when considering energyconstraints, PB < Pgas/30, FRM B-fields with B0 = 3 G, andp < 2.3 (caution: this assumes a power-law scaling):F,COMA (5.3 . . .7.6) 10

13cm2s1

Potential of measuring the CR spectrum, the effectiveacceleration efficiency for diffusive shock acceleration, andrelate this to the history of structure formation shock waves(Mach number distribution).




The cosmic magnetized webProperties of cluster magnetic fields

Cluster turbulence


41/54

Outline

1 Cosmological simulations with cosmic raysMotivation and observations








Cluster turbulence





Cluster turbulence


42/54

Cosmic web: Mach number

1

10

-15 -10 -5 0 5 1 0 15-15

-10

-5

0

5

10

15

-15 -10 -5 0 5 10 15

x [ h-1 Mpc ]

-15

-10

-5

0

5

10

15

y

[h-1Mpc]

-15 -10 -5 0 5 1 0 15-15

-10

-5

0

5

10

15

M

diss/

diss





Cluster turbulence


43/54

Radio gischt (relics): primary CRe (1.4 GHz)

10-8

10-6

10-4

10-2

100

S,primary

[mJyarcm

in-2h70

2]

-15 -10 -5 0 5 10 15-15

-10

-5

0

5

10

15

-15 -10 -5 0 5 10 15

x [ h-1Mpc ]

-15

-10

-5

0

5

10

15

y

[h-1Mpc]

-15 -10 -5 0 5 10 15-15

-10

-5

0

5

10

15





Cluster turbulence


44/54

Radio gischt: primary CRe (150 MHz)

10-8

10-6

10-4

10-2

100

S,primary

[mJyarcmin-2h70

2]

-15 -10 -5 0 5 10 15-15

-10

-5

0

5

10

15

-15 -10 -5 0 5 10 15

x [ h-1Mpc ]

-15

-10

-5

0

5

10

15

y

[h-1Mp

c]

-15 -10 -5 0 5 10 15-15

-10

-5

0

5

10

15





Cluster turbulence


45/54

Radio gischt: primary CRe (15 MHz)

10-8

10-6

10-4

10-2

100

S,primary

[mJyarcmin-2h70

2]

-15 -10 -5 0 5 10 15-15

-10

-5

0

5

10

15

-15 -10 -5 0 5 10 15

x [ h-1Mpc ]

-15

-10

-5

0

5

10

15

y

[h-1Mp

c]

-15 -10 -5 0 5 10 15-15

-10

-5

0

5

10

15





Cluster turbulence

R di i h i CR (15 MH )


46/54

Radio gischt: primary CRe (15 MHz), slower magnetic decline

10-8

10-6

10-4

10-2

100

S,primary

[mJyarcmin-2h70

2]

-15 -10 -5 0 5 10 15-15

-10

-5

0

5

10

15

-15 -10 -5 0 5 10 15

x [ h-1Mpc ]

-15

-10

-5

0

5

10

15

y

[h-1Mp

c]

-15 -10 -5 0 5 10 15-15

-10

-5

0

5

10

15





Cluster turbulence

R di i ht ill i t i ti fi ld


47/54

Radio gischt illuminates cosmic magnetic fields

1

3

2

-2 -1 0 1 2-2

-1

0

1

2

-2 -1 0 1 2

x [ h-1 Mpc ]

-2

-1

0

1

2

y[

h-1Mpc]

-2 -1 0 1 2-2

-1

0

1

2

Mdiss

/diss

Structure formation shocks triggered

by a recent merger of a large galaxy

cluster.

-2 -1 0 1 2-2

-1

0

1

2

-2 -1 0 1 2

x [ h-1Mpc ]

-2

-1

0

1

2

y[

h-1Mpc]

-2 -1 0 1 2-2

-1

0

1

2-2 -1 0 1 2

-2

-1

0

1

2

red/yellow: shock-dissipated energy,

blue/contours: 150 MHz radio gischt

emission from shock-accelerated CRe





Cluster turbulence

Diff l t di i i i bl


48/54

Diffuse cluster radio emission an inverse problemExploring the magnetized cosmic web

Battaglia, CP, Sievers, Bond, Enlin (2008):

By suitably combining the observables associated with diffusepolarized radio emission at low frequencies ( 150 MHz,GMRT/LOFAR/MWA/LWA), we can probe

the strength and coherence scale of magnetic fields on scales ofgalaxy clusters,

the process of diffusive shock acceleration of electrons,

the existence and properties of the WHIM,

the exploration of observables beyond the thermal clusteremission which are sensitive to the dynamical state of thecluster.





Cluster turbulence

P l ti f f i t di li i i l t


49/54

Population of faint radio relics in merging clustersProbing the large scale magnetic fields

Finding radio relics in 3D cluster simulations using a friends-of-friends finderwith an emission threshold relic luminosity function

10-3

10-2

10-1

1

101

S[

mJyarcmin-2]

-2 -1 0 1 2-2

-1

0

1

2

-2 -1 0 1 2

x [ h-1Mpc ]

-2

-1

0

1

2

y

[h-1Mpc]

-2 -1 0 1 2-2

-1

0

1

2

radio map with GMRT emissivity threshold

10-3

10-2

10-1

1

101

S[

mJyarcmin-2]

-2 -1 0 1 2-2

-1

0

1

2

-2 -1 0 1 2

x [ h-1Mpc ]

-2

-1

0

1

2

y

[h-1Mpc]

-2 -1 0 1 2-2

-1

0

1

2

theoretical threshold (towards SKA)





Cluster turbulence

Relic luminosity function theory


50/54

Relic luminosity function theory

Relic luminosity function is very sensitive to large scale behavior of the

magnetic field and dynamical state of cluster:

1

10

Numberofrelics

25 26 27 28 29 30 31 32

10-2 10-1 100 101 102 103 104F [mJy] for a cluster @ z ~ 0.05

B = 0.3

= 150MHz, B0 = 5 G

B = 0.5B = 0.7

B = 0.9

log(J/J0), J0 = 1 erg/Hz/s/ster

varying magnetic decline with radius

1

10

Numberofrelics

25 26 27 28 29 30 31 32

10-2 10-1 100 101 102 103 104F [mJy] for a cluster @ z ~ 0.05

B0 = 10 G

= 150MHz, B = 0.5

B0 = 5 GB0 = 2.5 G

log(J/J0), J0 = 1 erg/Hz/s/ster

varying overall normalization of the mag-

netic field





Cluster turbulence

Rotation measure (RM)


51/54

Rotation measure (RM)

RM maps and power spectra have the potential to infer the magnetic

pressure support and discriminate the nature of MHD turbulence in clusters:

-150

-75

0

75

150

RM[radm-2]

-0.4 -0.2 0.0 0.2 0.4x [ Mpc]

-0.4

-0.2

0.0

0.2

0.4

y[Mpc]

-5 0 5arcmin

-5

0

5

arcmin

1

10

P[RM](k)k2[

rad2m

-4]

10-7

10-6

P

[Bz]

(k)k2[

G2M

pc]

P[RM] (k)P[Bz]

(k)

1 10 100k[h Mpc-1]

1

10

P

[RM](k)k2[

rad2m

-4]

MFR1

MFR2

MFR3

Left: RM map of the largest relic, right: Magnetic and RM power spectrum comparing

Kolmogorow and Burgers turbulence models.





Cluster turbulence

Conclusions


52/54

Conclusions

In contrast to the thermal plasma, the non-equilibrium distributions ofCRs preserve the information about their injection and transportprocesses and provide thus a unique window of current and paststructure formation processes and diffusive shock acceleration!

1 Universal distribution of CR protons determined by maximum

shock acceleration efficiency max and adiabatic transport:mapping between the hadronic -ray emission and max cosmological simulations are indispensable for exploring this(non-linear) map spectral shape illuminates the process of structure formation

2 Primary radio (gischt) emission traces the magnetized cosmicweb; sensitive to electron acceleration efficiency Faraday rotation on polarized Mpc-sized relics allowsdetermining the nature of the intra-cluster turbulence





Cluster turbulence

Conclusions


53/54

Conclusions









The cosmic magnetized web


Cluster turbulence

Conclusions


54/54

Conclusions






pfrommer: particle acceleration and radiation from galaxy clusters

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