The Physics and Cosmology of Tev Blazars

Physics of blazar heating The intergalactic medium Structure formation

The Physics and Cosmology of TeV Blazars

Christoph Pfrommer1

in collaboration with

Avery E. Broderick2, Phil Chang3, Ewald Puchwein1, Volker Springel1

1Heidelberg Institute for Theoretical Studies, Germany 2Perimeter Institute/University of Waterloo, Canada 3University of Wisconsin-Milwaukee, USA

Jul 11, 2012 / Meeting, DFG Research Unit FOR 1254

Christoph Pfrommer The Physics and Cosmology of TeV Blazars Physics of blazar heating The intergalactic medium Structure formation The Hitchhiker’s Guide to . . . Blazar Heating

the extragalactic TeV Universe plasma physics for cosmologists

Christoph Pfrommer The Physics and Cosmology of TeV Blazars Physics of blazar heating The intergalactic medium Structure formation The Hitchhiker’s Guide to . . . Blazar Heating

the extragalactic TeV Universe plasma physics for cosmologists consequences for intergalactic magnetic ﬁelds extragalactic gamma-ray background thermal history of the Universe Lyman-α forest “missing dwarf galaxies” H I mass function galaxy cluster bimodality

1 Physics of blazar heating TeV emission from blazars Plasma instabilities and magnetic ﬁelds Extragalactic gamma-ray background

2 The intergalactic medium Properties of blazar heating Thermal history of the IGM The Lyman-α forest

3 Structure formation Formation of dwarf galaxies Puzzles in galaxy formation Conclusions

Christoph Pfrommer The Physics and Cosmology of TeV Blazars Physics of blazar heating TeV emission from blazars The intergalactic medium Plasma instabilities and magnetic ﬁelds Structure formation Extragalactic gamma-ray background TeV gamma-ray astronomy

H.E.S.S. MAGIC I

VERITAS MAGIC II

There are several classes of TeV sources: Galactic - pulsars, BH binaries, supernova remnants Extragalactic - mostly blazars, two starburst galaxies

narrow line region relativistic jet

broad line region

dusty torus

central SMBH

continuous sequence from LBL–IBL–HBL TeV blazars are dim (very sub-Eddington) TeV blazars have rising spectra in the Fermi band (α < 2) deﬁne TeV blazar = hard IBL + HBL

Ghisellini (2011), arXiv:1104.0006

Christoph Pfrommer The Physics and Cosmology of TeV Blazars mean free path for this depends on the density of 1 eV photons: → λγγ ∼ (35 ... 700) Mpc for z = 1 ... 0 → pairs produced with energy of 0.5 TeV (γ = 106) these pairs inverse Compton scatter off the CMB photons: → mean free path is λIC ∼ λγγ /1000 → producing gamma-rays of ∼ 1 GeV

2 E ∼ γ ECMB ∼ 1 GeV

each TeV point source should also be a GeV point source

Physics of blazar heating TeV emission from blazars The intergalactic medium Plasma instabilities and magnetic ﬁelds Structure formation Extragalactic gamma-ray background Propagation of TeV photons

1 TeV photons can pair produce with 1 eV EBL photons:

+ − γTeV + γeV → e + e

Christoph Pfrommer The Physics and Cosmology of TeV Blazars these pairs inverse Compton scatter off the CMB photons: → mean free path is λIC ∼ λγγ /1000 → producing gamma-rays of ∼ 1 GeV

2 E ∼ γ ECMB ∼ 1 GeV

each TeV point source should also be a GeV point source

1 TeV photons can pair produce with 1 eV EBL photons:

+ − γTeV + γeV → e + e

mean free path for this depends on the density of 1 eV photons: → λγγ ∼ (35 ... 700) Mpc for z = 1 ... 0 → pairs produced with energy of 0.5 TeV (γ = 106)

Christoph Pfrommer The Physics and Cosmology of TeV Blazars each TeV point source should also be a GeV point source

1 TeV photons can pair produce with 1 eV EBL photons:

+ − γTeV + γeV → e + e

mean free path for this depends on the density of 1 eV photons: → λγγ ∼ (35 ... 700) Mpc for z = 1 ... 0 → pairs produced with energy of 0.5 TeV (γ = 106) these pairs inverse Compton scatter off the CMB photons: → mean free path is λIC ∼ λγγ /1000 → producing gamma-rays of ∼ 1 GeV

2 E ∼ γ ECMB ∼ 1 GeV

1 TeV photons can pair produce with 1 eV EBL photons:

+ − γTeV + γeV → e + e

2 E ∼ γ ECMB ∼ 1 GeV

each TeV point source should also be a GeV point source

Every TeV source should be associated with a 1-100 GeV gamma-ray halo – not seen! TeV spectra

expected cascade TeV detections emission

Fermi constraints

Neronov & Vovk (2010)

Christoph Pfrommer The Physics and Cosmology of TeV Blazars IC mean free path E −1 x ∼ 0.1 Mpc IC 3 TeV for the associated 10 GeV IC photons the Fermi angular resolution is 0.2◦ or θ ∼ 3 × 10−3 rad

xIC −16 > θ → B & 10 G rL

TeV beam of e+/e− are deﬂected out of the line of sight reducing the GeV IC ﬂux → lower limit on B Larmor radius E E B −1 rL = ∼ 30 Mpc eB 3 TeV 10−16 G

IC mean free path E −1 x ∼ 0.1 Mpc IC 3 TeV for the associated 10 GeV IC photons the Fermi angular resolution is 0.2◦ or θ ∼ 3 × 10−3 rad

xIC −16 > θ → B & 10 G rL

How do beams of e+/e− propagate through the IGM? plasma processes are important interpenetrating beams of charged particles are unstable consider the two-stream instability:

one frequency (timescale) and one length in the problem: s ω 4πe2n γc γ p = e , λ = ∼ 14 × 2 p 10 cm 6 γ γ me ωp 10 ρ¯(z=0)

wave-like perturbation with k||v beam, longitudinal charge oscillations in background plasma (Langmuir wave): initially homogeneous beam-e−: attractive (repulsive) force by potential maxima (minima) e− attain lowest velocity in potential minima → bunching up e+ attain lowest velocity in potential maxima → bunching up

p p

e− e −

wave-like perturbation with k||v beam, longitudinal charge oscillations in background plasma (Langmuir wave): beam-e+/e− couple in phase with the background perturbation: enhances background potential stronger forces on beam-e+/e− → positive feedback exponential wave-growth → instability

+ + Φ e e

p p e− e−

e− e −

particles with v & vphase: pair energy → plasma waves → growing modes

particles with v . vphase: plasma wave energy → pairs → damped modes

k oblique to v beam: real word perturbations don’t choose “easy” alignment = P all orientations

Bret (2009), Bret+ (2010)

excluded for collective consider a light beam plasma phenomena penetrating into relatively dense plasma maximum growth rate

oblique nbeam ∼ 0.4 γ ωp nIGM

IC oblique instability beats IC by two orders of magnitude

Broderick, Chang, C.P. (2012)

Christoph Pfrommer The Physics and Cosmology of TeV Blazars → plasma instabilities dissipate the beam’s energy, no (little) energy left over for inverse Compton scattering off the CMB

non-linear saturation: non-linear evolution of these instabilities at these density contrasts is not known expectation from PIC simulations suggest substantial isotropization of the beam assume that they grow at linear rate up to saturation

→ plasma instabilities dissipate the beam’s energy, no (little) energy left over for inverse Compton scattering off the CMB

Christoph Pfrommer The Physics and Cosmology of TeV Blazars absence of γGeV’s has signiﬁcant implications for . . . intergalactic B-ﬁeld estimates γ-ray emission from blazars: spectra, background

additional IGM heating has signiﬁcant implications for . . . thermal history of the IGM: Lyman-α forest late time structure formation: dwarfs, galaxy clusters

 IC off CMB → γGeV + −  γTeV + γeV → e + e →  plasma instabilities → heating IGM

Christoph Pfrommer The Physics and Cosmology of TeV Blazars additional IGM heating has signiﬁcant implications for . . . thermal history of the IGM: Lyman-α forest late time structure formation: dwarfs, galaxy clusters

 IC off CMB → γGeV + −  γTeV + γeV → e + e →  plasma instabilities → heating IGM

absence of γGeV’s has signiﬁcant implications for . . . intergalactic B-ﬁeld estimates γ-ray emission from blazars: spectra, background

 IC off CMB → γGeV + −  γTeV + γeV → e + e →  plasma instabilities → heating IGM

absence of γGeV’s has signiﬁcant implications for . . . intergalactic B-ﬁeld estimates γ-ray emission from blazars: spectra, background

additional IGM heating has signiﬁcant implications for . . . thermal history of the IGM: Lyman-α forest late time structure formation: dwarfs, galaxy clusters

Broderick, Chang, C.P. (2012)

Christoph Pfrommer The Physics and Cosmology of TeV Blazars → TeV blazar spectra are not suitable to measure IGM B-ﬁelds!

it is thought that TeV blazar spectra might constrain IGM B-fields this assumes that cooling mechanism is IC off the CMB + deflection from magnetic fields beam instabilities may allow high-energy e+/e− pairs to self scatter and/or lose energy isotropizes the beam – no need for B-field

. 1–10% of beam energy to IC CMB photons

→ TeV blazar spectra are not suitable to measure IGM B-ﬁelds!

collect luminosity of all 23 TeV blazars with good spectral measurements account for the selection effects (sky coverage, duty cycle, galactic occultation, TeV ﬂux limit) TeV blazar luminosity density is a scaled version (ηB ∼ 0.2%) of that of quasars!

Broderick, Chang, C.P. (2012)

Christoph Pfrommer The Physics and Cosmology of TeV Blazars → assume that they trace each other for all redshifts!

Quasars and TeV blazars are: regulated by the same mechanism contemporaneous elements of a single AGN population: TeV-blazar activity does not lag quasar activity

Broderick, Chang, C.P. (2012)

Quasars and TeV blazars are: regulated by the same mechanism contemporaneous elements of a single AGN population: TeV-blazar activity does not lag quasar activity → assume that they trace each other for all redshifts!

Broderick, Chang, C.P. (2012)

Hopkins+ (2007)

Christoph Pfrommer The Physics and Cosmology of TeV Blazars → evolving (increasing) blazar population consistent with observed declining evolution (Fermi ﬂux limit)!

number evolution of TeV blazars that are expected to have been observed by Fermi vs. observed evolution colors: different ﬂux (luminosity) limits η = 0.8, 1.6, 3.1 connecting the Fermi and the TeV band:

LTeV,min(z) = η LFermi,min(z)

Broderick, Chang, C.P. (2012)

LTeV,min(z) = η LFermi,min(z)

Broderick, Chang, C.P. (2012) → evolving (increasing) blazar population consistent with observed declining evolution (Fermi ﬂux limit)!

Hopkins+ (2007)

Christoph Pfrommer The Physics and Cosmology of TeV Blazars Physics of blazar heating TeV emission from blazars The intergalactic medium Plasma instabilities and magnetic ﬁelds Diffuse BackgroundStructure formation IntensityExtragalactic gamma-ray background Fermi probes “dragons” of the gamma-ray sky Fermi LAT Extragalactic Gamma-ray Background

-6 10 2

Intensity (GeV photons per cm sec steradian) -7 Unknown 10 contributors

Background accounted for by unresolved AGN

-8 10 0.1 1 10 100 Energy (GeV)

assume all TeV blazars have identical intrinsic spectra:

ˆ 1 FE = LFE ∝ , αL−1 α−1 (E/Eb) + (E/Eb)

Eb is break energy,

αL < α are low and high-energy spectral indexes extragalactic gamma-ray background (EGRB):

∞ 0 dN 1 Z η Λ˜ (z )Fˆ 0 0 0 2 0 B Q E −τE (E ,z ) E (E, z) = dV (z ) 2 e , dE 4π z 4πDL

E0 = E(1 + z0) is gamma-ray energy at emission, ˜ ΛQ is physical quasar luminosity density,

ηB ∼ 0.2% is blazar fraction, τ is optical depth

dotted: unabsorbed EGRB due to TeV blazars dashed: absorbed EGRB due to TeV blazars solid: absorbed EGRB, after subtracting the resolved TeV blazars (z < 0.25)

Broderick, Chang, C.P. (2012)

Christoph Pfrommer The Physics and Cosmology of TeV Blazars Physics of blazar heating Properties of blazar heating The intergalactic medium Thermal history of the IGM Structure formation The Lyman-α forest Outline

1 Physics of blazar heating TeV emission from blazars Plasma instabilities and magnetic ﬁelds Extragalactic gamma-ray background

2 The intergalactic medium Properties of blazar heating Thermal history of the IGM The Lyman-α forest

3 Structure formation Formation of dwarf galaxies Puzzles in galaxy formation Conclusions

HI,HeI−/HeII−reionization

photoheating 103 standard blazar standard blazar fit ] 1 ¡ optimistic blazar 2 10 optimistic blazar fit blazar heating 10

0.1 10x larger

Heating Rates [eV Gyr heating

photoheating 10 2

10 5 2 1 1 +z

Chang, Broderick, C.P. (2012)

Christoph Pfrommer The Physics and Cosmology of TeV Blazars 4 TIGM ∼ 10 K (1 eV) at mean density (z ∼ 2) kT ε = ∼ −9 th 2 10 mpc

radiative energy ratio emitted by BHs in the Universe (Fukugita & Peebles 2004)

−4 −5 εrad = η Ωbh ∼ 0.1 × 10 ∼ 10

fraction of the energy energetic enough to ionize H I is ∼ 0.1:

−6 εUV ∼ 0.1εrad ∼ 10 → kT ∼ keV

−3 2 photoheating efﬁciency ηph ∼ 10 → kT ∼ ηph εUV mpc ∼ eV (limited by the abundance of H I/He II due to the small recombination rate) −3 2 blazar heating efﬁciency ηbh ∼ 10 → kT ∼ ηbh εrad mpc ∼ 10 eV (limited by the total power of TeV sources)

Physics of blazar heating Properties of blazar heating The intergalactic medium Thermal history of the IGM Structure formation The Lyman-α forest Blazar heating vs. photoheating

total power from AGN/stars vastly exceeds the TeV power of blazars

Christoph Pfrommer The Physics and Cosmology of TeV Blazars radiative energy ratio emitted by BHs in the Universe (Fukugita & Peebles 2004)

−4 −5 εrad = η Ωbh ∼ 0.1 × 10 ∼ 10

fraction of the energy energetic enough to ionize H I is ∼ 0.1:

−6 εUV ∼ 0.1εrad ∼ 10 → kT ∼ keV

Physics of blazar heating Properties of blazar heating The intergalactic medium Thermal history of the IGM Structure formation The Lyman-α forest Blazar heating vs. photoheating

total power from AGN/stars vastly exceeds the TeV power of blazars 4 TIGM ∼ 10 K (1 eV) at mean density (z ∼ 2) kT ε = ∼ −9 th 2 10 mpc

Christoph Pfrommer The Physics and Cosmology of TeV Blazars fraction of the energy energetic enough to ionize H I is ∼ 0.1:

−6 εUV ∼ 0.1εrad ∼ 10 → kT ∼ keV

Physics of blazar heating Properties of blazar heating The intergalactic medium Thermal history of the IGM Structure formation The Lyman-α forest Blazar heating vs. photoheating

total power from AGN/stars vastly exceeds the TeV power of blazars 4 TIGM ∼ 10 K (1 eV) at mean density (z ∼ 2) kT ε = ∼ −9 th 2 10 mpc

radiative energy ratio emitted by BHs in the Universe (Fukugita & Peebles 2004)

−4 −5 εrad = η Ωbh ∼ 0.1 × 10 ∼ 10

Christoph Pfrommer The Physics and Cosmology of TeV Blazars −3 2 photoheating efﬁciency ηph ∼ 10 → kT ∼ ηph εUV mpc ∼ eV (limited by the abundance of H I/He II due to the small recombination rate) −3 2 blazar heating efﬁciency ηbh ∼ 10 → kT ∼ ηbh εrad mpc ∼ 10 eV (limited by the total power of TeV sources)

Physics of blazar heating Properties of blazar heating The intergalactic medium Thermal history of the IGM Structure formation The Lyman-α forest Blazar heating vs. photoheating

total power from AGN/stars vastly exceeds the TeV power of blazars 4 TIGM ∼ 10 K (1 eV) at mean density (z ∼ 2) kT ε = ∼ −9 th 2 10 mpc

radiative energy ratio emitted by BHs in the Universe (Fukugita & Peebles 2004)

−4 −5 εrad = η Ωbh ∼ 0.1 × 10 ∼ 10

fraction of the energy energetic enough to ionize H I is ∼ 0.1:

−6 εUV ∼ 0.1εrad ∼ 10 → kT ∼ keV

Christoph Pfrommer The Physics and Cosmology of TeV Blazars −3 2 blazar heating efﬁciency ηbh ∼ 10 → kT ∼ ηbh εrad mpc ∼ 10 eV (limited by the total power of TeV sources)

Physics of blazar heating Properties of blazar heating The intergalactic medium Thermal history of the IGM Structure formation The Lyman-α forest Blazar heating vs. photoheating

total power from AGN/stars vastly exceeds the TeV power of blazars 4 TIGM ∼ 10 K (1 eV) at mean density (z ∼ 2) kT ε = ∼ −9 th 2 10 mpc

radiative energy ratio emitted by BHs in the Universe (Fukugita & Peebles 2004)

−4 −5 εrad = η Ωbh ∼ 0.1 × 10 ∼ 10

fraction of the energy energetic enough to ionize H I is ∼ 0.1:

−6 εUV ∼ 0.1εrad ∼ 10 → kT ∼ keV

−3 2 photoheating efﬁciency ηph ∼ 10 → kT ∼ ηph εUV mpc ∼ eV (limited by the abundance of H I/He II due to the small recombination rate)

total power from AGN/stars vastly exceeds the TeV power of blazars 4 TIGM ∼ 10 K (1 eV) at mean density (z ∼ 2) kT ε = ∼ −9 th 2 10 mpc

radiative energy ratio emitted by BHs in the Universe (Fukugita & Peebles 2004)

−4 −5 εrad = η Ωbh ∼ 0.1 × 10 ∼ 10

fraction of the energy energetic enough to ionize H I is ∼ 0.1:

−6 εUV ∼ 0.1εrad ∼ 10 → kT ∼ keV

105 only photoheating standard BLF optimistic BLF

[K] 10

103 20 10 5 2 1 1 +z

Chang, Broderick, C.P. (2012)

Christoph Pfrommer The Physics and Cosmology of TeV Blazars blazars and extragalactic background light are uniform: → blazar heating rate independent of density → makes low density regions hot → causes inverted temperature-density relation, T ∝ 1/δ

Physics of blazar heating Properties of blazar heating The intergalactic medium Thermal history of the IGM Structure formation The Lyman-α forest Evolution of the temperature-density relation

no blazar heating

Christoph Pfrommer The Physics and Cosmology of TeV Blazars → makes low density regions hot → causes inverted temperature-density relation, T ∝ 1/δ

Physics of blazar heating Properties of blazar heating The intergalactic medium Thermal history of the IGM Structure formation The Lyman-α forest Evolution of the temperature-density relation

no blazar heating

blazars and extragalactic background light are uniform: → blazar heating rate independent of density

no blazar heating

blazars and extragalactic background light are uniform: → blazar heating rate independent of density → makes low density regions hot → causes inverted temperature-density relation, T ∝ 1/δ

no blazar heating with blazar heating

Chang, Broderick, C.P. (2012)

blazars and extragalactic background light are uniform: → blazar heating rate independent of density → makes low density regions hot → causes inverted temperature-density relation, T ∝ 1/δ

Christoph Pfrommer The Physics and Cosmology of TeV Blazars blazars completely change the thermal history of the diffuse IGM and late-time structure formation

Physics of blazar heating Properties of blazar heating The intergalactic medium Thermal history of the IGM Structure formation The Lyman-α forest Blazars cause hot voids

no blazar heating with blazar heating

Chang, Broderick, C.P. (2012)

no blazar heating with blazar heating

Chang, Broderick, C.P. (2012)

blazars completely change the thermal history of the diffuse IGM and late-time structure formation

Puchwein, C.P., Springel, Broderick, Chang (2012): L = 15h−1Mpc boxes with 2 × 3843 particles one reference run without blazar heating three with blazar heating at different levels of efﬁciency (address uncertainty)

used an up-to-date model of the UV background (Faucher-Giguère+ 2009)

no blazar heating intermediate blazar heating 7.0 -7 -7 8 6.5 − ) = N HI H ( N 6.0 10 log -6 -8 -6

5.5 ) -5 -5 K / T

( 5.0

10 -4 -4 log 4.5

4.0 -3 -3 -2 -2

1 3.5 log10(Mpix/(h− M )) Viel et al. 2009, F=0.1-0.8 Viel et al. 2009, F=0-0.9 5 6 7 8 9 10 3.0 2 1 0 1 2 3 2 1 0 1 2 3 − − − − log (ρ/ ρ ) 10 h i

Puchwein, C.P., Springel, Broderick, Chang (2012)

1.0

0.8 τ − e

0.6

0.4 transmitted ﬂux fraction 0.2 no blazar heating intermediate b. h. 0.0 0.25 0.20

τ 0.15 − e

∆ 0.10 0.05 0.00 0 1000 2000 3000 4000 1 velocity [km s− ] Puchwein+ (2012)

Christoph Pfrommer The Physics and Cosmology of TeV Blazars no blazar heating 3.5 weak blazar heating intermediate blazar heating strong blazar heating

) Becker et al. 2011 K 4 10

( 3.0 / ) ∆ ( T

2.5 temperature

2.0

2.0 2.2 2.4 2.6 2.8 3.0 redshift z Puchwein+ (2012)

Redshift evolutions of effective optical depth and IGM temperature match data only with additional heating, e.g., provided by blazars!

Physics of blazar heating Properties of blazar heating The intergalactic medium Thermal history of the IGM Structure formation The Lyman-α forest Optical depths and temperatures

no blazar heating 0.5 weak blazar heating intermediate blazar heating

eff strong blazar heating τ 0.4 Viel et al. 2004 Tytler et al. 2004 FG ’08 0.3 effective optical depth 0.2

0.1 1.8 2.0 2.2 2.4 2.6 2.8 3.0 redshift z

no blazar heating no blazar heating 0.5 3.5 weak blazar heating weak blazar heating intermediate blazar heating intermediate blazar heating strong blazar heating

) Becker et al. 2011 eff

strong blazar heating K τ 0.4 Viel et al. 2004 4 10

( 3.0 /

Tytler et al. 2004 ) ∆ FG ’08 ( T 0.3 2.5 effective optical depth temperature 0.2

2.0

0.1 1.8 2.0 2.2 2.4 2.6 2.8 3.0 2.0 2.2 2.4 2.6 2.8 3.0 redshift z redshift z Puchwein+ (2012)

Redshift evolutions of effective optical depth and IGM temperature match data only with additional heating, e.g., provided by blazars!

tuned UV background 101 no blazar heating weak blazar heating intermediate blazar heating strong blazar heating 100 Kim et al. 2007

z = 2.52

1 10− 101 PDF of transmitted ﬂux fraction

100

z = 2.94

1 10− 0.0 0.2 0.4 0.6 0.8 1.0 transmitted ﬂux fraction

Puchwein+ (2012)

decomposing Lyman-α forest into individual Voigt proﬁles allows studying the thermal broadening of absorption lines

0.08 13 2 NHI > 10 cm− no blazar heating 0.07 2.75 < z < 3.05 weak blazar heating intermediate blazar h. strong blazar heating 0.06 Kirkman & Tytler ’97 ] 1

− 0.05 skm [

b 0.04

0.03 PDF of 0.02

0.01

0.00 0 10 20 30 40 50 60 1 b[kms− ] Puchwein+ (2012)

improvement in modelling the Lyman-α forest is a direct consequence of the peculiar properties of blazar heating: heating rate independent of IGM density → naturally produces the inverted T –ρ relation that Lyman-α forest data demand recent and continuous nature of the heating needed to match the redshift evolutions of all Lyman-α forest statistics magnitude of the heating rate required by Lyman-α forest data ∼ the total energy output of TeV blazars (or equivalently ∼ 0.2% of that of quasars)

Christoph Pfrommer The Physics and Cosmology of TeV Blazars Physics of blazar heating Formation of dwarf galaxies The intergalactic medium Puzzles in galaxy formation Structure formation Conclusions Outline

1 Physics of blazar heating TeV emission from blazars Plasma instabilities and magnetic ﬁelds Extragalactic gamma-ray background

2 The intergalactic medium Properties of blazar heating Thermal history of the IGM The Lyman-α forest

3 Structure formation Formation of dwarf galaxies Puzzles in galaxy formation Conclusions

Christoph Pfrommer The Physics and Cosmology of TeV Blazars entropy evolution

only photoheating 2 10 standard BLF optimistic BLF ]

2 10 [keV cm

K 1

0.1 20 10 5 2 1 1 +z

C.P., Chang, Broderick (2012) −2/3 evolution of entropy, Ke = kTne , governs structure formation blazar heating: late-time, evolving, modest entropy ﬂoor

Physics of blazar heating Formation of dwarf galaxies The intergalactic medium Puzzles in galaxy formation Structure formation Conclusions Entropy evolution

temperature evolution

105 only photoheating standard BLF optimistic BLF

[K] 10

103 20 10 5 2 1 1 +z

temperature evolution entropy evolution

105 only photoheating only photoheating 2 standard BLF 10 standard BLF optimistic BLF optimistic BLF ]

2 10

[K] 10

T [keV cm

K 1

0.1 103 20 10 5 2 1 20 10 5 2 1 1 +z 1 +z

C.P., Chang, Broderick (2012) −2/3 evolution of entropy, Ke = kTne , governs structure formation blazar heating: late-time, evolving, modest entropy ﬂoor

Christoph Pfrommer The Physics and Cosmology of TeV Blazars hotter IGM → higher IGM pressure → higher Jeans mass:

!1/2 c3 T 3 M T 3/2 M ∝ s ∝ IGM → J,blazar ≈ blazar 30 J 1/2 & ρ ρ MJ,photo Tphoto

→ depends on instantaneous value of cs “ﬁltering mass” depends on full thermal history of the gas: accounts for delayed response of pressure in counteracting gravitational collapse in the expanding universe apply corrections for non-linear collapse

Physics of blazar heating Formation of dwarf galaxies The intergalactic medium Puzzles in galaxy formation Structure formation Conclusions Dwarf galaxy formation – Jeans mass

thermal pressure opposes gravitational collapse on small scales characteristic length/mass scale below which objects do not form

Christoph Pfrommer The Physics and Cosmology of TeV Blazars “ﬁltering mass” depends on full thermal history of the gas: accounts for delayed response of pressure in counteracting gravitational collapse in the expanding universe apply corrections for non-linear collapse

Physics of blazar heating Formation of dwarf galaxies The intergalactic medium Puzzles in galaxy formation Structure formation Conclusions Dwarf galaxy formation – Jeans mass

thermal pressure opposes gravitational collapse on small scales characteristic length/mass scale below which objects do not form hotter IGM → higher IGM pressure → higher Jeans mass:

!1/2 c3 T 3 M T 3/2 M ∝ s ∝ IGM → J,blazar ≈ blazar 30 J 1/2 & ρ ρ MJ,photo Tphoto

→ depends on instantaneous value of cs

thermal pressure opposes gravitational collapse on small scales characteristic length/mass scale below which objects do not form hotter IGM → higher IGM pressure → higher Jeans mass:

!1/2 c3 T 3 M T 3/2 M ∝ s ∝ IGM → J,blazar ≈ blazar 30 J 1/2 & ρ ρ MJ,photo Tphoto

1 + δ = 1, z = 10 blazar heating 1012 reion only photoheating M ~ 1011 M linear theory F o

] 10 10 • O 10 MF ~ 10 Mo M -1 h [ F non−linearlinear theorytheory 8 M 10 non-linear theory optimistic blazar standard blazar only photoheating 106 F

M / 10

F, blazar 1 M 10 1 1 + z

C.P., Chang, Broderick (2012)

mean density void, 1 + δ = 0.5

δ 1 + δ = 1, z = 10 12 1 + = 0.5, z = 10 1012 reion 10 reion

] 10

] 10 • O • O 10 10 M M -1 -1 h h [ [ F F linear theory linear theory 8 8 M M 10 non-linear theory 10 non-linear theory optimistic blazar optimistic blazar standard blazar standard blazar only photoheating 6 only photoheating 106 10 F F M M / / 10 10 F, blazar F, blazar 1

1 M M 10 1 10 1 1 + z 1 + z C.P., Chang, Broderick (2012) blazar heating efﬁciently suppresses the formation of void dwarfs 11 within existing DM halos of masses < 3 × 10 M (z = 0) may reconcile the number of void dwarfs in simulations and the paucity of those in observations

Springel+ (2008)

Dolphin+ (2005)

Substructures in cold DM simulations much more numerous than observed number of Milky Way satellites!

10 Myr M110

100 Myr 10 Gyr

1 Gyr

Dolphin+ (2005)

isochrone ﬁtting for different metallicities → star formation histories

Dolphin+ (2005)

τ red: form > 10 Gyr, z > 2

Christoph Pfrommer The Physics and Cosmology of TeV Blazars satellite luminosity function

no blazar heating: linear theory non−linear theory

Maccio+ (2010) blazar heating suppresses late satellite formation, may reconcile low observed dwarf abundances with CDM simulations

Physics of blazar heating Formation of dwarf galaxies The intergalactic medium Puzzles in galaxy formation Structure formation Conclusions Milky Way satellites: formation history and abundance

satellite formation time

Maccio & Fontanot (2010)

late forming satellites (< 10 Gyr) not observed!

satellite formation time satellite luminosity function

Maccio & Fontanot (2010)

no blazar heating: linear theory non−linear theory late forming satellites (< 10 Gyr) not observed!

Maccio+ (2010) blazar heating suppresses late satellite formation, may reconcile low observed dwarf abundances with CDM simulations

Mo+ (2005)

H I-mass function is too flat (i.e., gas version of missing dwarf problem!) photoheating and SN feedback too inefficient IGM entropy floor of K ∼ 15 keV cm2 at z ∼ 2 − 3 successful!

Christoph Pfrommer The Physics and Cosmology of TeV Blazars novel mechanism; dramatically alters thermal history of the IGM: uniform and z-dependent preheating rate independent of density → inverted T –ρ relation quantitative self-consistent picture of high-z Lyman-α forest signiﬁcantly modiﬁes late-time structure formation: suppresses late dwarf formation (in accordance with SFHs): “missing satellites”, void phenomenon, H I-mass function group/cluster bimodality of core entropy values

Physics of blazar heating Formation of dwarf galaxies The intergalactic medium Puzzles in galaxy formation Structure formation Conclusions Conclusions on blazar heating

Christoph Pfrommer The Physics and Cosmology of TeV Blazars signiﬁcantly modiﬁes late-time structure formation: suppresses late dwarf formation (in accordance with SFHs): “missing satellites”, void phenomenon, H I-mass function group/cluster bimodality of core entropy values

Physics of blazar heating Formation of dwarf galaxies The intergalactic medium Puzzles in galaxy formation Structure formation Conclusions Conclusions on blazar heating

explains puzzles in high-energy astrophysics: lack of GeV bumps in blazar spectra without IGM B-fields unified TeV blazar-quasar model explains Fermi source counts and extragalactic gamma-ray background novel mechanism; dramatically alters thermal history of the IGM: uniform and z-dependent preheating rate independent of density → inverted T –ρ relation quantitative self-consistent picture of high-z Lyman-α forest significantly modifies late-time structure formation: suppresses late dwarf formation (in accordance with SFHs): “missing satellites”, void phenomenon, H I-mass function group/cluster bimodality of core entropy values

mass accretion history mass accretion rates

1015 5

z0.5 = 0.42 ) z 4 ( a 14 10 z0.5 = 0.55 ]

• O 3 / d log z0.5 = 0.70 200c [ M M 200c 2 M 13 10 z0.5 = 0.86 = d log z0.5 = 0.95 S 1

1012 0 1 1 1 + z 1 + z

C.P., Chang, Broderick (2012)

most cluster gas accretes after z = 1, when blazar heating can have a large effect (for late forming objects)!

Christoph Pfrommer The Physics and Cosmology of TeV Blazars Planck stacking of optical clusters

Planck Collaboration (2011)

Do optical and X-ray/Sunyaev-Zel’dovich cluster observations probe the same population? (Hicks+ 2008, Planck Collaboration 2011)

Physics of blazar heating Formation of dwarf galaxies The intergalactic medium Puzzles in galaxy formation Structure formation Conclusions Entropy ﬂoor in clusters

Cluster entropy proﬁles

Cavagnolo+ (2009)

Cluster entropy proﬁles Planck stacking of optical clusters

Cavagnolo+ (2009) Planck Collaboration (2011)

Do optical and X-ray/Sunyaev-Zel’dovich cluster observations probe the same population? (Hicks+ 2008, Planck Collaboration 2011)

varying formation time varying cluster mass

1000 1000

13 14 z = 0 M200 = 3 x 10 MO • M200 = 1 x 10 MO • , z = 0.5 13 z = 0.5 M200 = 3 x 10 MO • , z = 0.5 13 z = 1 M200 = 1 x 10 MO • , z = 0.5 z = 2 ] ] 2 2 100 100 [keV cm [keV cm e e K K

10 optimistic blazar 10 optimistic blazar

0.01 0.10 1.00 0.01 0.10 1.00 r / R200 r / R200 C.P., Chang, Broderick (2012) assume big fraction of intra-cluster medium collapses from IGM: redshift-dependent entropy excess in cores greatest effect for late forming groups/small clusters

Borgani+ (2005) greater initial entropy K0 2 → more shock heating K 0 = 25 keV cm → greater increase in K0 over entropy ﬂoor

net K0 ampliﬁcation of 3-5 expect:

preheated 2 median Ke,0 ∼ 150 keV cm no preheating + floor 2 max. Ke,0 ∼ 600 keV cm no preheating

Borgani+ (2005)

Christoph Pfrommer The Physics and Cosmology of TeV Blazars time-dependent preheating + gravitational reprocessing → CC-NCC bifurcation (two attractor solutions) need hydrodynamic simulations to conﬁrm this scenario

Physics of blazar heating Formation of dwarf galaxies The intergalactic medium Puzzles in galaxy formation Structure formation Conclusions Cool-core versus non-cool core clusters

cool hot

Cavagnolo+ (2009)

Physics of blazar heating Formation of dwarf galaxies The intergalactic medium Puzzles in galaxy formation Structure formation Conclusions Cool-core versus non-cool core clusters

cool hot

early forming, late forming, t > t merger cool t merger < tcool

Cavagnolo+ (2009)

cool hot

early forming, late forming, t > t merger cool t merger < tcool

Cavagnolo+ (2009)

time-dependent preheating + gravitational reprocessing → CC-NCC bifurcation (two attractor solutions) need hydrodynamic simulations to conﬁrm this scenario

Christoph Pfrommer The Physics and Cosmology of TeV Blazars AGNs cannot transform CC to NCC clusters (on a buoyancy timescale)

Physics of blazar heating Formation of dwarf galaxies The intergalactic medium Puzzles in galaxy formation Structure formation Conclusions How efﬁcient is heating by AGN feedback?

E (kT = 5.9 keV) C.P., Chang, Broderick (2011) b, 2500 X 104 Eb, 2500(kTX = 3.5 keV)

Eb, 2500(kTX = 2.0 keV)

Eb, 2500(kTX = 1.2 keV) erg] 2

58 10

Eb, 2500(kTX = 0.7 keV) [10 tot PV 4 = 0

cav 10 E

cool cores non-cool cores 10-2

1 10 100 2 Ke,0 [keV cm ]

Christoph Pfrommer The Physics and Cosmology of TeV Blazars AGNs cannot transform CC to NCC clusters (on a buoyancy timescale)

Physics of blazar heating Formation of dwarf galaxies The intergalactic medium Puzzles in galaxy formation Structure formation Conclusions How efﬁcient is heating by AGN feedback?

E (kT = 5.9 keV) C.P., Chang, Broderick (2011) b, 2500 X 104 Eb, 2500(kTX = 3.5 keV)

Eb, 2500(kTX = 2.0 keV)

Eb, 2500(kTX = 1.2 keV) erg] 2

58 10

Eb, 2500(kTX = 0.7 keV) [10 tot PV 4 = 0

cav 10 E

cool cores non-cool cores 10-2

1 10 100 2 Ke,0 [keV cm ]

Christoph Pfrommer The Physics and Cosmology of TeV Blazars AGNs cannot transform CC to NCC clusters (on a buoyancy timescale)

Physics of blazar heating Formation of dwarf galaxies The intergalactic medium Puzzles in galaxy formation Structure formation Conclusions How efﬁcient is heating by AGN feedback?

E (kT = 5.9 keV) C.P., Chang, Broderick (2011) b, 2500 X 104 Eb, 2500(kTX = 3.5 keV)

Eb, 2500(kTX = 2.0 keV)

Eb, 2500(kTX = 1.2 keV) erg] 2

58 10

Eb, 2500(kTX = 0.7 keV) [10 tot PV 4 = 0

cav 10 E

cool cores non-cool cores 10-2

1 10 100 2 Ke,0 [keV cm ]

Christoph Pfrommer The Physics and Cosmology of TeV Blazars AGNs cannot transform CC to NCC clusters (on a buoyancy timescale)

Physics of blazar heating Formation of dwarf galaxies The intergalactic medium Puzzles in galaxy formation Structure formation Conclusions How efﬁcient is heating by AGN feedback?

E (kT = 5.9 keV) C.P., Chang, Broderick (2011) b, 2500 X 104 Eb, 2500(kTX = 3.5 keV)

Eb, 2500(kTX = 2.0 keV)

Eb, 2500(kTX = 1.2 keV) erg] 2

58 10

Eb, 2500(kTX = 0.7 keV) [10 tot PV 4 = 0

cav 10 E

cool cores non-cool cores 10-2

1 10 100 2 Ke,0 [keV cm ]

Christoph Pfrommer The Physics and Cosmology of TeV Blazars AGNs cannot transform CC to NCC clusters (on a buoyancy timescale)

Physics of blazar heating Formation of dwarf galaxies The intergalactic medium Puzzles in galaxy formation Structure formation Conclusions How efﬁcient is heating by AGN feedback?

E (kT = 5.9 keV) C.P., Chang, Broderick (2011) b, 2500 X 104 Eb, 2500(kTX = 3.5 keV)

Eb, 2500(kTX = 2.0 keV)

Eb, 2500(kTX = 1.2 keV) erg] 2

58 10

Eb, 2500(kTX = 0.7 keV) [10 tot PV 4 = 0

cav 10 E

cool cores non-cool cores 10-2

1 10 100 2 Ke,0 [keV cm ]

Christoph Pfrommer The Physics and Cosmology of TeV Blazars AGNs cannot transform CC to NCC clusters (on a buoyancy timescale)

Physics of blazar heating Formation of dwarf galaxies The intergalactic medium Puzzles in galaxy formation Structure formation Conclusions How efﬁcient is heating by AGN feedback?

E (kT = 5.9 keV) C.P., Chang, Broderick (2011) b, 2500 X 104 Eb, 2500(kTX = 3.5 keV)

Eb, 2500(kTX = 2.0 keV)

Eb, 2500(kTX = 1.2 keV) erg] 2

58 10

Eb, 2500(kTX = 0.7 keV) [10 tot PV 4 = 0

cav 10 E

cool cores non-cool cores 10-2

1 10 100 2 Ke,0 [keV cm ]

Christoph Pfrommer The Physics and Cosmology of TeV Blazars AGNs cannot transform CC to NCC clusters (on a buoyancy timescale)

Physics of blazar heating Formation of dwarf galaxies The intergalactic medium Puzzles in galaxy formation Structure formation Conclusions How efﬁcient is heating by AGN feedback?

E (kT = 5.9 keV) C.P., Chang, Broderick (2011) b, 2500 X 104 Eb, 2500(kTX = 3.5 keV)

Eb, 2500(kTX = 2.0 keV)

Eb, 2500(kTX = 1.2 keV) erg] 2

58 10

Eb, 2500(kTX = 0.7 keV) [10 tot PV 4 = 0

cav 10 E

cool cores non-cool cores 10-2

1 10 100 2 Ke,0 [keV cm ]

E (kT = 5.9 keV) C.P., Chang, Broderick (2011) b, 2500 X 104 Eb, 2500(kTX = 3.5 keV)

Eb, 2500(kTX = 2.0 keV)

Eb, 2500(kTX = 1.2 keV) erg] 2

58 10

Eb, 2500(kTX = 0.7 keV) [10 tot PV 4 = 0 max K0

cav 10 E

cool cores non-cool cores 10-2

1 10 100 2 Ke,0 [keV cm ]

AGNs cannot transform CC to NCC clusters (on a buoyancy timescale)

Christoph Pfrommer The Physics and Cosmology of TeV Blazars