red stellar populations ir spectra abundance patterns & kinematics extreme environments -...
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red stellar populationsred stellar populations
IR spectraIR spectra
abundance patterns & kinematics abundance patterns & kinematics
extreme environmentsextreme environments
-- galactic bulgegalactic bulge - young extragalactic clusters- young extragalactic clusters - SB galaxies- SB galaxies
resolvedresolved into single stars: • in galaxy fields up to a few Mpc• in stellar clusters within the LG
integratedintegrated: • stellar clusters up to a few Mpc
• galaxies pop synthesis multiple ages, metallicities
NGC1569 – SSCsNGC1569 – SSCs HHST – NICMOS
D = 2.2 MpcD = 2.2 Mpc
ddSSCSSC 100 mas100 mas
Aloisi et al. 2001, AJ 121, 1425Aloisi et al. 2001, AJ 121, 1425 Origlia et al. 2001, AJ 122, 815Origlia et al. 2001, AJ 122, 815
M31 – G1 M31 – G1 HST – ACS
D = 0.77 MpcD = 0.77 Mpc
ddG1G1 a few arcseca few arcsec
each sequence in the most suitable rangeeach sequence in the most suitable range hothot in the in the UV-opticalUV-optical, , coolcool in the in the IRIR
largerlarger bbaasseelliinne e
betterbetter definition of stellar & population parameters definition of stellar & population parameters
temperature, gravity, metallicity, mass, IMF, reddening etc.temperature, gravity, metallicity, mass, IMF, reddening etc. nebular nebular vsvs stellar contributions, mass loss, SF rates etc. stellar contributions, mass loss, SF rates etc.
each environment in the most suitable rangeeach environment in the most suitable range
metal poormetal poor, , low reddeninglow reddening (e.g. halos) in the (e.g. halos) in the UV-optical UV-optical metal richmetal rich, , high reddeninghigh reddening (e.g bulges) in the (e.g bulges) in the IRIR
Post-Main Sequence stars
Red Supergiant (RSG): 8-40 Mo, age 5-100 Myr
Asymptotic Giant Branch (AGB): <8 Mo, age>100 Myr
Red Giant Branch (RGB): <2 Mo , age > few Gyr
in the near IR dominate
the stellar luminosity of stellar clusters & normal galaxies
over the nebular & AGN emission in active galaxies
Teff < 5000 K
chemical abundances & abundance patterns of Fe,CNO, chemical abundances & abundance patterns of Fe,CNO, -elements -elements SF history, timescales, rates, etc., primordial SF history, timescales, rates, etc., primordial vsvs self-enrichment self-enrichment etc.etc.
radial velocities & velocity dispersionsradial velocities & velocity dispersions distances, masses, dynamical interactions etc.distances, masses, dynamical interactions etc.
near IRnear IR range crucial to study: range crucial to study:galaxy bulgesgalaxy bulgesextragalactic star clustersextragalactic star clustersyoung SSCs & star forming galaxies young SSCs & star forming galaxies host galaxies of both type I & II AGNshost galaxies of both type I & II AGNs
optimal spectral resolutionsoptimal spectral resolutions: :
stars & stellar clusters: 1-10 Km/sstars & stellar clusters: 1-10 Km/s galaxies: 10-100 Km/sgalaxies: 10-100 Km/s
neutral atomic lines neutral atomic lines Fe, Si, Ca, Mg, Ti, Al, NaFe, Si, Ca, Mg, Ti, Al, Na
OH, CO, CN molecular bands OH, CO, CN molecular bands very sensitive to very sensitive to CC, , OO & & NN abundances abundances
the SF history of a stellar system is imprinted the SF history of a stellar system is imprinted in their chemical abundance patterns in their chemical abundance patterns
elementselements: : O, Si, Ca, Mg,TiO, Si, Ca, Mg,Ti type II SNe type II SNe withwith massive progenitors massive progenitors
released released in thein the ISM ISM from thefrom the very beginning very beginning of theof the SF onset SF onset
Fe - group elementsFe - group elements type I SNe type I SNe withwith intermediate mass progenitors intermediate mass progenitors
C, N, s,r-process elementsC, N, s,r-process elements AGB AGB withwith low-intermediate mass progenitorslow-intermediate mass progenitors
released released in thein the ISM ISM afterafter 1 Gyr 1 Gyr from thefrom the SF onset SF onset
elements: O, Si, Ca, Mg, Ti elements: O, Si, Ca, Mg, Ti
[[ /F
e]/F
e]
0.00.0
0.30.3
0.50.5
[Fe/H][Fe/H]0.00.0-1.0-1.0-2.0-2.0
IMFIMF
SFRSFR
Galactic HaloGalactic Halostars formed from a gasstars formed from a gasmainly enriched by SNII mainly enriched by SNII on a relatively short timescale on a relatively short timescale
Galactic DiskGalactic Diskstars formed from a gasstars formed from a gasalso enriched by SNIa also enriched by SNIa on a much longer timescale on a much longer timescale
Galactic Bulge ?Galactic Bulge ?
Optical spectrasee e.g. Fullbright, McWilliam & Rich ‘06; Zoccali et al. ‘06
K giants: (V-K)0<3, Teff >4000 K red clump at V015
outer Bulge with Av < 2
M giants: severly affected by molecular blanketing & blendingIR spectra
K giants: too warm, faint lines
M giants: (V-K)0>3, Teff<4000 K RGB Tip inner Bulge, AIR negligible
lum
ino
sit
y
temperature
RGB Tip
HB
SURVEY of cluster & field M giants SURVEY of cluster & field M giants in collaboration with R.M. Rich & E. Valentiin collaboration with R.M. Rich & E. Valenti
H band H band (1.5-1.8 micron)(1.5-1.8 micron) echelle spectraechelle spectra with with NIRSPEC at Keck IINIRSPEC at Keck II
[/Fe] enhancement
elements: O, Si, Ca, Mg, Ti elements: O, Si, Ca, Mg, Ti
[[ /F
e]/F
e]
0.00.0
0.30.3
0.50.5
[Fe/H][Fe/H]0.00.0-1.0-1.0-2.0-2.0
IMFIMF
SFRSFR
Galactic HaloGalactic Halostars formed from a gasstars formed from a gasmainly enriched by SNII mainly enriched by SNII on a relatively short timescale on a relatively short timescale
Galactic DiskGalactic Diskstars formed from a gasstars formed from a gasalso enriched by SNIa also enriched by SNIa on a much longer timescale on a much longer timescale
Galactic Bulge, E galGalactic Bulge, E galhalo – like but at higher SFR halo – like but at higher SFR
NGC 6946NGC 6946WPC2@HST F555W F555W 6945 SSC6945 SSC
D = 5.9 Mpc
= 10.4 km/sM = 1.7 x 106 Mo
age = 10-15 Myr
L/M consistent with a Salpeter IMF
Larsen et al. 2001, ApJ, 556, 801
Larsen, Origlia, Brodie & Gallagher, 2006, MNRAS, 368, 10
= 9.1 km/s
[Fe/H] = -0.45 +/- 0.1
[Ca,Mg,Al/Fe] = +0.25 +/- 0.15
[O,Ti/Fe] = +0.29 +/- 0.10
[Si/Fe] = +0.08 +/- 0.18
[C/Fe] = -0.25 +/-0 .11
12C/13C = 8 +/- 2
NGC 6946 – SSC NGC 6946 – SSC
NIRSPEC@Keck R=25,000NIRSPEC@Keck R=25,000
… … calibrating suitable stellar abundance calibrating suitable stellar abundance tracers tracers
for integrated spectroscopy of distant for integrated spectroscopy of distant galaxiesgalaxies
velocity dispersion / rotationvelocity dispersion / rotation line line broadeningbroadening
in the visual range:SB galaxies severely contaminated
by nebular emission and AGN
in the near - IR range:SB galaxies poorly contaminated
by nebular emission and AGN
RSGs dominate the luminosity
diagnostics: stellar vs gaseous abundances
stars (red supergiants) in the IR: enrichment before the last burst of SF
hot gas in the X-ray with Chandra & XMM:real-time enrichment by the last burst of SF
cool gas in the visual:enrichment by the previous or the last burst of SF?it depends on the cooling & mixing timescales…
nnear–IRear–IR: TNG/NICS: TNG/NICS XXrayray: XMM RGS/MOS: XMM RGS/MOS
M 82M 82
NGC 253NGC 253
nnear–IRear–IR spectra spectra X-ray spectraX-ray spectra
Teff = 3800 – 4000 K log g = 0.5= 3 km/s
point sourcespoint sources
power law =0.8
NH = 8x1021 cm-2
diffuse hot gas
optically thin thermal plasma kT=0.7 kev
NH = 4x1021 cm-2
Teff = +/- 200 K
log g = +/- 0.5 = +/- 1 km/s
[X/H] = +/- 0.2 dex2 level
best-fit modelsbest-fit models
chemical enrichment by recursive bursts
oxygen puzzling…
[Fe/H] = [Fe/H] = 0.35 +/- 0.20.35 +/- 0.2
stars: [Si,Mg/Fe] = +0.4
[O/Fe] = +0.4
hot gas: [Si,Mg/Fe] = +0.5
[O/Fe] = 0.2
M 82M 82
[Fe/H] = [Fe/H] = 0.50 +/- 0.20.50 +/- 0.2
stars: [Si,Mg/Fe] = +0.3
[O/Fe] = +0.3
hot gas: [Si,Mg/Fe] = +0.7
[O/Fe] = 0.1
NGC 253NGC 253
Origlia et al. 2004, ApJ, 606, 862Origlia et al. 2004, ApJ, 606, 862
oxygen underabundance
working hypothesis
(Marcolini, , Strickland, D’Ercole, Heckman & Hoopes, 2005, MNRAS, 362, 626)
SNII winds interact with cool gas clouds & and heat them
heavier metals (Si, Mg etc.) form in the SNII wind
O forms in the outer region of the wind (OVII & OVIII soft XX) and/or in the heated clouds (OV & OVI UVUV)
IR spectroscopy crucial to measure star kinematics in type I AGNsIR spectroscopy crucial to measure star kinematics in type I AGNs
MMBHBH – – relationrelation
Merritt & Ferrarese 2001, ApJ, 547, 140Merritt & Ferrarese 2001, ApJ, 547, 140
Gebhardt e
t al. ‘
01
Gebhardt e
t al. ‘
01
Ferra
rese
& M
errit
t ‘0
0
Ferra
rese
& M
errit
t ‘0
0
MMBHBH
4.80.5
M/Lstellar :burst on/off
hosts of AGNshosts of AGNs
no nuclear SB in Seys 1no nuclear SB in Seys 1
nuclear SB in 30 – 40 % nuclear SB in 30 – 40 %
obscured / Seys 2obscured / Seys 2
Oliva et al., 1999, A&A 350, 4Origlia & Oliva, 2000, New Astr. Rev. 44, 25
((Cid Fernandes et al. 2001, ApJ 558, 81)Cid Fernandes et al. 2001, ApJ 558, 81)
35 type II Seyferts35 type II Seyferts morphological type: S0, Sa, Sbmorphological type: S0, Sa, Sb
stellar content: stellar content: 50%50% nuclear nuclear SBSB (< 1 kpc scale(< 1 kpc scale), ), 50%50% old SP old SP correlation correlation betweenbetween SB (H SB (H && AGN ([OIII]) luminosity AGN ([OIII]) luminosity
((Kauffman et al. 2003, MNRAS 346, 1055) Kauffman et al. 2003, MNRAS 346, 1055)
22,600 narrow-line AGNs22,600 narrow-line AGNs type 2 Seys type 2 Seys & & QSOs QSOs withwith same [OIII] same [OIII] and and zz have have similar hostssimilar hosts
in massive SB galaxies RSGs dominate over an underlying older SP
1.0 < [Fe/H] < 0.0, 8<age<50 Myr Teff 3600 – 4000 K
log g 0.0 – 1.0 3 5 km/s
< RSG > Teff = 3800 200 K
log g = 0.5 0.5 41 km/s
[A/H] = 0.2 dex
in the in the near IRnear IR: : young SPs:young SPs: red supergiants red supergiants intermediate/oldintermediate/old SPs:SPs: red giants red giants
stellar parameters:
< RSG > from young MC clusters
codecode: : Origlia et al. (1993 Origlia et al. (1993 2004model atmospheresmodel atmospheres: : ATLAS9, Johnson et al. ’80, NextGen, [Plez]ATLAS9, Johnson et al. ’80, NextGen, [Plez]stellar parametersstellar parameters: : near IR photometry + moleculesnear IR photometry + moleculesLTELTE
full spectral synthesisfull spectral synthesis equivalent width measurement of selected linesequivalent width measurement of selected lines
spectral fitting/equivalent width measurements < 0.1 dex< 0.1 dex
log gflog gf 0.2 0.2 0.1 dex 0.1 dex
random errors:random errors:
stellar parameters 0.1 - 0.2 dex0.1 - 0.2 dex
solar abundances 0.1 0.1 0.1 dex 0.1 dex
systematic errors:systematic errors:
nLTE correctionsnLTE corrections negligible at T>3000 Knegligible at T>3000 K
model atmospheres negligible, opacity dominated by Hnegligible, opacity dominated by H--
other sources of error:other sources of error:
• [OI] lines [OI] lines ( ( 6300,6364 6300,6364 Å ))• OI triplet OI triplet ( ( 7772,7774,7775 7772,7774,7775 Å ))
• OH molecular transitionsOH molecular transitions IR lines IR lines ( ( 1.5-1.8 1.5-1.8 mm ))
low temperatures, high metallicity low temperatures, high metallicity domaindomain
bulge
vertical abundance gradientsvertical abundance gradients ? ?
observing old SPs in the galactic centerobserving old SPs in the galactic center
self-enrichmentself-enrichment asas traced traced by by O-NaO-Na & & Mg-AlMg-Al anti-correlationanti-correlation? ? perhaps yes perhaps yes ……
Mg-Al anti-correlation
12C/13C 10 extra - mixing
halo
bulge
nebular spectranebular spectra
emission lines: [OII][OIII][NII][SII]
best ne ,Te diagnostics (e.g. McCall, 1984, MNRAS 208, 253):
ne I([SII] I([SII] Te [++] I([OIII] I([OIII]
Te [+] I([NII] I([NII]
emission lines: [OII][OIII][NII][SII]
best ne ,Te diagnostics (e.g. McCall, 1984, MNRAS 208, 253):
ne I([SII] I([SII] Te [++] I([OIII] I([OIII]
Te [+] I([NII] I([NII]
alternative Te diagnostics at high Z:(e.g. Pagel et al. , 1979, MNRAS, 189, 95
Storchi-Bergmann et al. 1994, ApJ429, 572)
empirical calibrations
alternative Te diagnostics at high Z:(e.g. Pagel et al. , 1979, MNRAS, 189, 95
Storchi-Bergmann et al. 1994, ApJ429, 572)
empirical calibrations
abundances at high Z:(McGaugh, 1991, ApJ 380, 140)
empirical calibrations
abundances at high Z:(McGaugh, 1991, ApJ 380, 140)
empirical calibrations
NGC 1569
BalmerBalmer jumpjump
HeII bumpHeII bump WR starsWR stars
few Myr old few Myr old
Gonzalez Delgado et al. 1997, ApJ 483, 705Gonzalez Delgado et al. 1997, ApJ 483, 705
SB galaxiesSB galaxies
8 SB galaxies
< [ / Fe] > = + 0.3 +/- 0.1 dex
< [ C / O ] > = - 0.5 +/- 0.2 dex
[12C / 13C] < 10
enhancement, enrichement by SNII C mixed in the stellar interiors
see also Read & Stevens 2002, MNRAS, 335, L36see also Read & Stevens 2002, MNRAS, 335, L36
[FeII][FeII] : shock excited, : shock excited, type II SNe type II SNe tracer tracer
Starburst99 modelsStarburst99 models
Origlia & Oliva 2000, A&A, 357, 61 Origlia & Oliva 2000, A&A, 357, 61
near IR near IR dust optically thindust optically thin
emission emission volume volume
LLdustdust ((SB SB ) ) LLdustdust ((AGN AGN ) ) / / NN
stellar clustersstellar clusters lessless efficient efficient thanthan
AGNAGN inin heating dust heating dust
why in AGNs & not in SBs?why in AGNs & not in SBs?TTdustdust 1000 1000
KK
RRdustdust 1 pc 1 pc
diagnostics : : optical photometry & spectroscopyoptical photometry & spectroscopy good for type II AGN not heavily obscured good for type II AGN not heavily obscured type I AGN hosts veiled by the AGN itselftype I AGN hosts veiled by the AGN itself
IR photometry & spectroscopyIR photometry & spectroscopy crucial to study obscured & type I AGNcrucial to study obscured & type I AGN
surveys : : optical: optical: SDSS + small size samples of type SDSS + small size samples of type II AGNII AGN
IR: IR: 2MASS2MASS ++ veryvery small size samples of type small size samples of type I & II AGNI & II AGN
KKVV
BBUU
RGBRGBAGBAGB
MSMS
MSMSMSMS
Renzini & Buzzoni 1986, Renzini & Buzzoni 1986, inin Spectral Evolution of GalaxiesSpectral Evolution of Galaxies, 195, 195Maraston 1998, MNRAS 300, 872Maraston 1998, MNRAS 300, 872
Woosley & Weaver, 1995, ApJS, 101, 181Woosley & Weaver, 1995, ApJS, 101, 181
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