Seyfert Jets : weak, slow

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Seyfert Jets weak, slow heavy

• Mark Whittle (Virginia)
• David Rosario (Virginia)
• John Silverman (Virginia/CfA)
• Charlie Nelson (Drake)
• Andrew Wilson (Maryland)

• Markarian 78 provides ideal access to
• Jet-gas interactions
  
• Nature of jets in radio quiet AGN

AJ papers I Data, II Ionization, III Jet
properties
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Overall Context

• Several inter-dependent components
• Jet flow relativistic material
• Lobe ionized line-emitting
  gas
• ISM thermal (low density)
  gas

LOBE
Relativistic gas
Line Emitting gas
ISM
Thermal gas
3
Overall Context

• Several physical processes
• entrainment of ISM by jet
• acceleration of line-emitting gas
• lobe expansion into ISM

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Available Data

• Emission Line image OIII (HST)
• Radio image 3.6cm (VLA)
• Emission Line kinematics (HST-STIS)
• Briefly review this ?

5
Overlay Radio (contours) OIII (image)
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4 STIS Slit Positions
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STIS low dispersion spectral data
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STIS high dispersion OIII 5007 data
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Slit B kinematic measurements
Peak Velocity
FWHM
-2 -1 0 1
2 3
East Nuc
West
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Extinction
Density
Line flux
Mass
Momentum
KE
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Region Properties

• 3 regions W-knot / E-fan / W-lobe
• Age size/velocity 0.4 / 4 / 8 Myr
• Ionized gas
• Mass 0.4 / 1.0 / 1.1 x 106 Msun
• Filling factor 30 / 1.5 / 0.5 x 10-4
• Covering factor 0.5 / 0.5 / 0.5

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Pressures Prel, Pem, Prad

• High 1-few x 10-10 dyne cm-2
• All decrease with radius ( r -1)
• both consistent with presence in bulge ISM
• Prel Pem ( Prad)
• pressure balance between relativistic ionized
  gas
• Prel can drive lobe expansion into ISM at VOIII
• Prel Prad cant quite accelerate ionized gas
• may need dynamical (ram) pressure of jet

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Energies Luminosities

• For each region, independently
• LUV(intercept) 1000 x 1040 erg s-1
• Lem 10LOIII 1000
• Lmec KE/age 1
• Lrel Erel/age 1
• (Lexp 1)
• Lradio 0.2

• NLR ionized by nuclear UV (not shocks)
• Nuclear photon power dominates all others
• KEgas Eexp come from radio-emitting flow

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The Jet Flow

• Jet properties are illusive but important
• Radio provides some access
• pressures, stored internal energy
• Emission lines very useful
• estimate jets luminosity momentum
• We follow approach of Bicknell et al (98)
• But, with different starting assumptions
• these lead to very different jet properties

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Starting Assumptions

• Jet Luminosity
• B98 Lj Lem 100LOIII (since shock
  generated)
• W04 Lj (EKE aeErel)/age aeElobe/age
• Lj(W) 10-3 Lj(B) 1040.5 erg s-1
• Jet Momentum Flux
• B98 Fj/Aj Pram ?emV2sh ?emV2OIII
• W04 Fj/Aj Pram am Gem /age /Aj
• Fj(W) 10-2 Fj(B) 1033.5 dyne

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JET LUMINOSITY
Emission Lines Lem
Bicknell et al 98
Shock
Lj
Lj Lem 100 x L5007
Our analysis
EKE S½M V2
Lj
1040.5 erg s-1
Elobe PV aeErel
Lj (EKE aeErel)/tage
ae asyn aad aff 2 10
For Mkn 78 other Seyferts Lj (us) 10-3
x Lj (B98)
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JET MOMENTUM FLUX
VshVem 500 km/s
Our analysis
Gem SM V
Fj
Gradual acceleration
Fj amGem / tage
1033.5 dyne
am adrag alcf 2 5
For Mkn 78 other Seyferts Fj (us) 10-2 x
Fj (B98)
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Starting Assumptions

• Jet Luminosity
• B98 Lj Lem 100LOIII (since shock
  generated)
• W04 Lj (EKE aeErel)/age aeElobe/age
• Lj(W) 10-3 Lj(B) 1040.5 erg s-1
• Let Momentum Flux
• B98 Fj/Aj Pram ?emV2sh ?emV2OIII
• W04 Fj/Aj Pram am Gem /age /Aj
• Fj(W) 10-2 Fj(B) 1033.5 dyne
• Our jets are much weaker

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Derivation of jet properties

• Model jet as 2 component system
• 1 Relativistic ratio defined by
  filling factor
• 2 Thermal ffrel (1 ffth)
• assume pressure balance Pth Prel B2min/8p
• Energy Ej KEth (5/2) Pth 4Prel KErel
  0
• Momentum Gj Gth Grel Gth Grel
  0
• Use estimates of Ej Gj Bmin Aj tage
• to derive many jet properties

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Jet Properties

• Jet energy (1040.5 erg s-1) momentum fluxes
• (1033.5 dyne) both dominated by thermal gas
• RKE KEj/Eint 10 / 2 / 1 ( Mj2)
• decrease suggests KE converted to internal
• Ram pressure Pram Fj/Aj 30 / 7 / 4 x Prel
• Pram(W04) 10-2 10-3 Pram(B98)
• Our jet is gentle
• Pram is significantly greater than Prel Prad
• hydrodynamic acceleration of ionized gas
• shocks in ionized gas are slow 10-50 km s-1

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Jet Properties

• Jet velocity Vj 2Lj/ Fj (1 Rke-1)
• Vj 0.3 3 x 103 km s-1 1 few x VOIII
• cf. Vj (B98) 15 90 x 103 km s-1
• our jet is slow
• Jet density ?j Fj/PramAj 0.15 cm-3
  ?ISM
• consistent with entrained ISM
• our jet is dense ? ?j /?ISM 1
• future simulations should consider ? 1 jets

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Jet Properties

• Jet temperature Mach
• Tth Pj /knth ? 106.5 107.5 K
• temp 0.2 0.7 fully virialized (cf. Pram gt
  Prel)
• Mj 5 / 2.5 / 1.5 ? jet is transonic
• ? efficient entrainment
  decollimation
• Jet mass transport Mth Fj/ Vj 0.5 Msun yr-1
  
• Mth tage 106 Msun thermal content of lobe
• Jet supplies lobes thermal component ?

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Jet Properties

• Jet synchrotron efficiency
• Rsyn Lradio /Lj Lradio tage /Elobe
• 0.1 Fff P-103/4
  t6 1-few
• similar to other radio sources (e.g. CSS
  FR-I,II)
• not obvious why very different types of jet

• cf. Rsyn(B98) 10-4 ltlt Rsyn(us)
• ? sub-equipartition fields, or
• ? low ffrel ? thermal component dominates

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Jet Base / Inner Jet

• Previous analysis applies to scales gt 100pc
• ? thermally dominated flow slow dense
• Is the flow created like this?
• could it start with ffrel 1.0, then entrain
  thermal gas
• probably not need Fj-b Fj-kpc
• Lj-b gt
  Lj-kpc
• S8Ghz lt
  3mJy
• implies Vj-b c and Lj-b 1043 erg s-1
• Most energy lost in core ? bright radio ? not
  seen
• Jet created with thermal component
• may define nature of radio quiet jets
• note cant be pure thermal (Rsyn too high)

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Conclusions

• Mkn 78 gives excellent access to jet properties
• Must combine radio and emission line data
• ? pressure, internal energy, KE, momentum, age
• For three regions, we find
• Age sequence 106 Msun low ff high cf
• P PISM Prel Pem Prad lobe expansion
  VOIII
• LUV Lem dominate shocks Erel EKE
• Model jet as 2 component relativistic thermal
• follow Bicknell et al 98 but dont use shocks
• instead, take Lj aeElobe/tage Fj amGem /
  tage
• derive jet properties ?

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Conclusions

• The jet is weak Lj 1040.5 erg/s Fj 1033.5
  dyne
• Thermal gas dominates jet energy momentum
• Pram 4 - 30 Pint gentle jet
• adequate to accelerate ionized gas
• drives slow shocks into ionized clouds (10-50 km
  s-1)
• Jet velocity 1-few VOIII relatively slow
  jet
• Jet density ?ISM dense jet
• Transonic Mj 2-5 Tth 106.5 K Rsyn
  normal
• Thermal content may fill radio lobe
• Jet base jet created with thermal component

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New HST Project 1 or 2 slits on six other
objects with evidence for JGI.
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Comparison Ours is a kinder, gentler jet.
Maybe more plausible ?
Jet Property Our Jet Bicknell et al
Energy flux Lj x 1 x 1000
Momentum flux Fj x 1 x 100
Velocity Vj 300 3000 km/s (1 few Vem) 15 90 x103 km/s (0.05c 0.3c)
Density nj 0.1 5 cm-3 0.1 5 cm-3
Ram pressure Pj x 1 x 100
Cloud shock Vsh 10 50 km/s 500 1000 km/s
Temperature Tj 106 K 109 K
Mach No. Mj 2 5 1 few