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The New Era in Stellar Populations Synthesis:

Black Magic +

Applications to active & not-so-active galaxies

R. Cid FernandesUFSC – Florianópolis -Brasil GH2004

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The team(s)• Witchcraft: L Sodré, J Gomes, Merlin, H. Potter, ...

• Seyfert 2s: Q Gu, J Melnick, E & R Terlevich, D Kunth, R Rodrigues Lacerda & B Joguet

• LLAGN: R González Delgado, H Schmitt, L Martins,T Storchi-Bergmann, E Pérez, T Heckman, C Leitherer

• SDSS: A Mateus, L Sodré, G Stasinska, J Gomes

• Ca-Triplet: L Vega, N Asari, A Garcia-Rissman,...

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The talk: Witchcraft & applications1 Witchcraft: Spectral fits using evolutionary synthesis models

HowWhat it can(’t) do for you

2 Seyfert 2s: Spectral fits using stars + FC (=AGN power-law)Residual spectra

3 LLAGN: Spectral fits using template galaxies + dustRadial variations (long-slit)

4 SDSS: Mass, age, Z*, *, ...Correlations, correlations & correlationsComparison with Kauffman et al

• Ca-Triplet: Stellar velocity dispersions & EW(CaT)

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The Conclusions1 Witchcraft: It works!! (= it fools people!)

Recovers well M*, <t*>, <Z*>, *, AV, ... Don’t recover details (but who cares?!)

2 Seyfert 2s: Heterogeneous Star-Formation historyFits uncover reflected AGN! (BLR & FC)

3 LLAGN: LINERS are all OLD & boringTransition Objects: OLD or “YOUNG” Young-TOs are dustyYoung-TOs = S(Duper)SC at 108–109 yr?

4 SDSS: A posteriori sanity check on synthesis!Correlations, correlations & correlations Comparison with Kauffman et al:

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1 – Witchcraft: Examples

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1 – Witchcraft: The recipe

’s (+ gas + dust

+ ...) ≈ SSP’s

x1 + x2 + x3

+ ...

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1 – Witchcraft: The ingredients

• 45 SSPs from Bruzual & Charlot (2003)15 ages: t = 1 Mr – 13 Gyr3 metallicites: 0.2 – 2.5 Zo

• 1 Reddening law (Cardelli et al 1989)

• 1 Gaussian LOSVD: G(v*,*)

• 2 or 3 smart collaborators

• 1 tea spoon of huitlacoche

• 5 galons of tequila

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1 – Witchcraft: The parameters

x = x(t,Z) = light FRACTION at from population t,Z

= “population vector”

= (x1,x2,...xN) = Star Formation History

Other parameters:

AV = dust (only 1 so far...) v* = “redshift”

* = velocity dispersion

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1 – Witchcraft: The nuts & bolts

+ Movies!08 , 32 , 39

• Data: O ± ; = 3650 – 8000 Ǻ – observed spectrum

• Model: M(x,AV,v*,*) – model spectrum

• Problem: How to estimate x1...xN, AV, v* e *?~ 45 + 3 = 48 paramerters!

• Method: Markov Chain Monte CarloMetropolis-Hastings + Simulated-annealingLikelyhood guided “random” walk

Prob(x,AV,v*,*| Data) ~ exp –{2 / 2}

2 = {O – M(x,AV,v*,*)}2

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Simulations: output ~ input

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Simulations: but ...

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CF, Gu, Melnick, Terlevich2, Kunth, Rodrigues Lacerda, Joguet 04

2 – The SF-History of Sey 2 nuclei

• 79 galaxies 65 Sey 2s

• ~ 200 pc

• Base = BC03 + FC

Strong FC in this Sey

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Coarse (but robust) description of the st pop

INTERMEDIATE108-9 yr

OLD 1010 yr

YOUNG (+ FC)106–7 yr

• Population vector:

Reduce x from N* ~ 20 => 3 components

x = (xY,xI,xO)

xY+ xI+ xO = 1 plane

CF et al 01, 04, GD et al 04

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Result #1: SFH of Sey 2s is very heterogenous!

• Population Vector:

x = flux-fractionx = ( Y+FC , I , O )

Y/FC = 5 Myr + -1.5 FC

I = 100 Myr – 1 Gyr

O = 1 – 10 Gyr

Old pop + burst

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Result #1: SFH of Sey 2s is very heterogenous!

~ 40% Starburst

+ Seyfert 2

composites

“pure/boring” Seyfert 2

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Result #1: SFH of Sey 2s is very heterogenous!

Continuous SF

InstantaneousBursts

Power-Law + E-gal

“Broad Line Sey 2s”

or “Sey 3s”

?!

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Result #2: Weak (scattered) BLR & FC!

• Starlight-subtracted spectra reveal weak broad H in 10/65 Seyfert 2s!

• Most of these have Hidden BLRs revealed in polarized spectra (Tran 95, 01)

• Spectral synthesis finds a strong FC component (~ 20%) in these “Broad Line Seyfert 2s”

Conclusion: Scattered light!

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WK

X [OI]/H

3 – LINERs & Transition Objects

OldYoung

Young TOs OldTOs

OldLINERs

Young LINERs

AG

N

CF etal 04GD etal 0405, 06 ...

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• Long-slit spec. of ~ 50 LLAGN

• Spatial Resolution ~ 1” ~ 100 pc

• Spectral synthesis of 521 extractions

• Base of template galaxies representing Y, I & O populations

St pop, extinction & brightness profiles

3 – LINERs & TOs

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WK(r)

3 – Radial Gradients in LLAGN

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x(r)

AV(r)

3 – Dust in LLAGN: AV(r)

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• Young-TOs have much more dust than

Old-TOs or Old-LINERs

Young-TOs

Old-TOs &

LINERs

3 – Dust in LLAGN: AV(r)

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• Young-TOs have much more dust than

Old-TOs or Old-LINERs

• Central 108-9 yr population is compact

R ≤ 100 pc

• M* ~ 107 Mo

• Super Duper SC??

Young-TOs

Old-TOs &

LINERs

3 – Dust & St pops in LLAGN

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2 + 3 = Evolution of (stars in) AGN?

<t*(Sey2)> < <t*(Young-TO)> < <t*(Old-TO)> = <t*(LINER)>

<t*(Starburst)> < <t*(Young-TO)> < <t*(Old-TO)>

To be continued....

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4 – Synthesis of 50k SDSS galaxies

Abílio Mateus (IAG), Jean Michel Gomes (UFSC)Laerte Sodré (IAG) & Grazyna Stasinska (Meudon)

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Products of the synthesis x = x(t,Z) : Star-formation & chemical histories M* : stellar Mass

t* & Z* : mean stellar age & metallicity

* : velocity dispersion

AV : extinction

Observed – Model F() = pure emission spectrum Emission line fluxes Nebular metallicity, extinction, ...

4 – SDSS: 1st results (including yesterday!)

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Stellar versus nebular extinction

AV (Balmer) = 0.3 + 1.8 AV (Stellar)

Normal Emission Line Galaxies

(= non-AGN)

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Stellar age x stellar age indicator

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Stellar age x nebular age indicator

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Stellar age x stellar mass

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Stellar mass x stellar metallicity

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Roberto: Can you read this?

Stellar X nebular metallicity

hahahahaha

blab

labl

abla

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Us X Them

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4 – SDSS: 1st results

Too much information!

Parameter

But great results!! Can’t be too wrong!

brigad!!

?