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Massive Stars: Feedback Effects in the Local Universe. Sally Oey University of Michigan Cathie Clarke IoA, Cambridge. Smith et al. / MCELS. HDF. Massive Star Feedback. Smith et al. / MCELS. Radiative Mechanical Chemical. > 8 M o 3 – 40 Myr lifetimes. - PowerPoint PPT Presentation
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Sally OeySally OeyUniversity of MichiganUniversity of Michigan
Cathie ClarkeCathie ClarkeIoA, CambridgeIoA, Cambridge
HDFSmith et al. / MCELS
Massive Stars:Massive Stars: Feedback Effects in the Local UniverseFeedback Effects in the Local Universe
Massive Star FeedbackMassive Star Feedback
Radiative
Mechanical
Chemical
Smith et al. / MCELS
> 8 Mo 3 – 40 Myr lifetimes
THE MASSIVE STARTHE MASSIVE STAR POPULATIONPOPULATION
NN** : Clustering law, field : Clustering law, field
mm : : Stellar IMFStellar IMF
Distributions:Distributions:
NGC 346
Nota et al. 2006
The IMF Upper-mass cutoffThe IMF Upper-mass cutoff
IC 1805 24
Berkeley 86 10
NGC 7380 11
NGC 1893 19
NGC 2244 12
Tr 14 / 16 82
LH 10 65
LH 117 / 118 40
TotalTotal 263263
R136a / 30 Dor > 650
Grand TotalGrand Total > 913 > 913
Massey et al. 1995
Massey & Hunter 1998,Hunter et al. 1997
Observed OB Observed OB associationsassociations
ages ages << 3 Myr, 3 Myr,m m >> 10 M 10 Moo
Arches: Figer 2002, 2005
R136a: Weidner & Kroupa 2004,Oey & Clarke 2005
mmmaxmax expectation valueexpectation value
dMdmmmmNm
)(*
up
10
M
10upmax
upmax mm maxmN*
Mm 10
Oey & Clarke (2005)
OB + 30 Dor
OB’s
impliesimplies mmupup< < 200 M200 Moo
cf. Elmegreen (2000): Milky Way mup~10,000 Mo
P < 0.002
P < 0.12
P < 0.02
P < 0.47
Probabilities for Probabilities for mmmax assuming assuming mmupup
mmupup ~ 150 M ~ 150 MOey & Clarke 2005
see also Koen (2006)
Entire sample
A Universal Clustering LawA Universal Clustering Law
Starbursts Starbursts Meurer et al. 1995Meurer et al. 1995
Globulars and Massive young ClustersGlobulars and Massive young ClustersElmegreen & Efremov 1997, Hunter et al. 2003Elmegreen & Efremov 1997, Hunter et al. 2003
-1.95 +/- 0.03
-2.00 +/- 0.08AntennaeAntennaeZhang & Fall 1999
*2
*** )( dNNdNNN
HST / B. Whitmore
a Universal Clustering Law a Universal Clustering Law andand a Universal IMF ? a Universal IMF ?
A steep field IMF a steepening A steep field IMF a steepening NN**
(fewer massive) (more low-(fewer massive) (more low-NN**) ) Massey (1995, 2002); Kroupa & Weidner (2003)
All -2.51 +/- 0.29
No field -2.27 +/- 0.38
Oey, King, & Parker 2004
SMC
Field stars fall on clustering
law
Fraction of Field Massive Stars:Fraction of Field Massive Stars:
1up*, 5772.0 ln ~ N
35% to 7% for 35% to 7% for NN*,up*,up = 10 to 10 = 10 to 1066
SMC: expect ~20%, see ~26%
modest dependence on total SFRmodest dependence on total SFR
Oey, King, & Parker 2004
RADIATIVE FEEDBACKRADIATIVE FEEDBACKNebular emissionNebular emission
H[S II], [O III], V, R
Large Magellanic Cloud
MCELS Smith et al. 2006
HII Region LFHII Region LF
Diffuse, warm Diffuse, warm ionized mediumionized medium
1.1. Break in slopeBreak in slope
2.2. Arm populations: shallower Arm populations: shallower a a Interarm populations: Interarm populations: steeper steeper aa
3.3. Hubble Type correlationHubble Type correlation aa ~ ~ 1.7 Sc – Im 1.7 Sc – Im
aa ~ 2.0 Sb – Sc ~ 2.0 Sb – Sc aa ~ 2.6 Sa ~ 2.6 Sa
log N(L)
log L
HII Region Luminosity FunctionHII Region Luminosity Function
a Universal Clustering Law a Universal Clustering Law andand a Universal IMF ? a Universal IMF ?
Oey & Clarke 1998
Ionization of the Diffuse WIMIonization of the Diffuse WIM
Field stars:Field stars:~ 50% WIM ionized by field~ 50% WIM ionized by field Oey et al. 2004; Hoopes & Walterbos 2000
Leaky nebulae:Leaky nebulae:LMC: up to 50% ionizing photons escape LMC: up to 50% ionizing photons escape Oey & Kennicutt 1997; Gerken, Walterbos, & Oey 2003
H Milky Way
WHAM: Reynolds et al.
MECHANICAL FEEDBACKMECHANICAL FEEDBACK
DEM L152 R. C. Smith & MCELS
Small Magellanic CloudStaveley-Smith et al. 1997
H I H[S II], [O III]
~100 pc diameter
Superbubble size distribution
5/45/35/2
5/35/1)/( Evolution
tnLP
tnLR
i
dLLdLLN 2 )( LF Mechanical
creation constant Burst /
+
+
Oey & Clarke 1997
Global Mechanical FeedbackGlobal Mechanical Feedback
=
clustering law
prediction
observed
Oey & Clarke 1997
Velocity distributionVelocity distribution
Oey & Clarke 1998
Predicted -3.5Observed -2.9 +/- 1.4 2/7 dvvdvvN
Predicted -2.8 +/- 0.4Observed -2.7 +/- 0.6
Size distributionSize distribution
dRRdRRN )( 3
Ionizing photons escape into ISM?
...into IGM?Reionization of
Universe?Escape of hot gas, stellar
products and ionizing photons?
geometry disk for factor correction
s km 10in dispersion velocity thermalISM~
M10in mass ISM total
1-10
10ISM,10
df
v
M
Clarke & Oey 2003
-1210ISM,10crit yr M /~ 15.0SFR dfvM
The first galaxies: ?The first galaxies: ?
MW:MW:1
crit yr M 1~SFR
LBGs:LBGs: 1crit yr M 1~SFR
Starbursts:Starbursts: 1crit yr M 1 SFR
1obs yr M 1~SFR
Ambiguous porositye.g., Oey & Clarke 1997
1obs yr M 20 1~SFR
1obs yr M 50 10~SFR
Lyman cont seen?Steidel et al. 2001
Critical SF Critical SF ThresholdThreshold
Lyman cont seen in Haro 11Bergvall et al. 2006
ESO 300-G14
NGC 7713
HR-band
SINGG: Survey of Ionization in SINGG: Survey of Ionization in Neutral Gas GalaxiesNeutral Gas Galaxies
H survey of HIPASS galaxies Meurer et al. (2006)
Oey et al. (2006, in prep)
IC 5052
High SF intensity : Less WIMHigh SF intensity : Less WIM
Possible causes Possible causes for high SFI : less WIM for high SFI : less WIM
Ionization source reduced:
– Output from HII regions reduced
– Fewer field OB stars
Starbursts occupy ISM and Remaining WIM density-bounded
Ionizing photons escape
Fraction of Field Massive Stars:Fraction of Field Massive Stars:
1up*, 5772.0 ln ~ N
35% to 7% for 35% to 7% for NN*,up*,up = 10 to 10 = 10 to 1066
SMC: expect ~20%, see ~26%
modest dependence on modest dependence on total SFRtotal SFR
Oey, King, & Parker 2004
recall
Diffuse fraction vs. total SFR Diffuse fraction vs. total SFR
geometry disk for factor correction
s km 10in dispersion velocity thermalISM~
M10in mass ISM total
1-10
10ISM,10
df
v
M
Clarke & Oey 2003
-1210ISM,10crit yr M /~ 15.0SFR dfvM
MW:MW:1
crit yr M 1~SFR
LBGs:LBGs: 1crit yr M 1~SFR
Starbursts:Starbursts: 1crit yr M 1 SFR
1obs yr M 1~SFR
Ambiguous porositye.g., Oey & Clarke 1997
1obs yr M 20 1~SFR
1obs yr M 50 10~SFR
Lyman cont seene.g., Steidel et al. 2001
Critical SF Critical SF ThresholdThreshold
J0355-42
recall
Trend for HI-poor galaxiesTrend for HI-poor galaxies
Ionization source reduced:
– Output from HII regions reduced
– Fewer field OB stars
Starbursts occupy ISM and Remaining WIM density-bounded
Ionizing photons escape
Likely
?
Possible causes Possible causes for high SFI : less WIM for high SFI : less WIM
LyC seen from Haro 11Bergvall et al. 2006
CHEMICAL FEEDBACKCHEMICAL FEEDBACK
Q: filling factor
n: generations
n
jjZZ
1
ZNPZN j
n
jj
1ISM
ZNPDn
ZN j
n
jkkjk
n
j
1
,11
kDk 1
Stochastic Inhomogeneous evolutionInhomogeneous evolution
Oey 2000, 2003
data: Carney et al. (1996)
Simple: Halo isSimple: Halo is evolved evolved
SIM: Halo is SIM: Halo is unevolvedunevolved
(Oey 2003)
Thick disk MDFThick disk MDF
Thin disk MDFThin disk MDF
Thick disk MDF
Bensby & Oey (2006), in prep
data: Nordstrom et al. (2004)
selection: Bensby et al. (2003, 2005)
Halo MDF
ZNPD
PD
j
n
jkkjk
n
j
n
kkk
F
,11
1,11
III
Zero-metallicity (Pop III) starsZero-metallicity (Pop III) stars
(Oey 2003)
ForFor Galactic halo model Galactic halo model
FIII ~ 4e-2
vs.vs. Observed Observed
FIII < 4e-4
Clear discrepancy!
OB clustering
H II LF, WIM
Superbubbles
*2
*** )( dNNdNNN
dvvdvvN
dRRdRRN
)(
)(
2/7
3
1up*, 5772.0 ln NField fraction:Field fraction:
ionizing WIM, IGM relation to IMF
ISM structure, evolution
mup ~ 150 Mo
Massive Star FeedbackMassive Star Feedback
Superwind Superwind thresholdthreshold
Metal enrichmentMetal enrichment
ZNPD
PD
j
n
jkkjk
n
j
n
kkk
F
,11
1,11
III
zNPzN j
n
jj
1ISM
zNPDn
zN j
n
jkkjk
n
j
1
,11
Simple Inhomogeneous Model GCE of unevolved systems
A self-consistent analytic approach
-11210ISM,10crit yr M ~15.0SFR
dfvM
starburst feedback to IGM
Massive Star FeedbackMassive Star Feedback OB population: clustering law, IMF
Radiative: HII LF, diffuse 104 K gas
Mechanical: superbubbles, superwinds diffuse 106 – 107 K gas
Chemical: inhomogeneous chemical evolution
Adiabatic shell evolutionAdiabatic shell evolution
SNe
ndstellar wi 2
1
e
51*
2
5/45/35/2
5/25/1
exp
5/35/1
t
ENL
vML
tnLP
tn
L
dt
dRv
tn
LR
i
L = mech luminosityn = ambient densityt = age
0.03
0.3
1.0
0.3
23
0.01 – 0.2
0.2
~ 1
M31
M33
LMC
SMC
IC 10
LG dwarfs
Milky Way (HII LF)
Milky Way (SN rate)
QGalaxy
Porosity: Hot, ionized mediumPorosity: Hot, ionized medium
Oey & Clarke 1997, Oey et al. 2002
volume filling factor of hot ISM
SFR tot
2/5H
~ )( ..
25
16.
e
min
MdRRNMM
RCTk
mM
R
R
superwind mass-loss rate
Mac Low & McCray (1988)
clustering = 2
e
min
e3D 1
1~ R
R
LQ
Starbursts (Clarke & Oey 2002)
Distributed Distributed
vsvs
NuclearNuclear
Equal contrib to porosity Equal contrib to porosity by all superbubble by all superbubble RR
Oey & Clarke 1997
He 2-10: He 2-10: Chandar et al. 2003
• Field population = SSC’sField population = SSC’s• LF LF LL-2-2
• Field OB’s formed Field OB’s formed in situin situ
R136a / 30 DorR136a / 30 DorConsistent with no mup Massey & Hunter 1998; Massey 2003
Suggests mup~ 150 Mo Selman et al. 1999
Consistent with Salpeter slope
Expect (14, 19)Expect (14, 19)
having having m > m > 120 M120 Moo
FoundFound (2, 9) stars (2, 9) stars
If no mup: 1.7x N*(85 – 120 Mo)
Massey & Hunter 1998
(See also Weidner & Kroupa 2004)
*
*
constant
2 Saturated""
/
varies
2 d"Unsaturate"
NL
l
a
NL
l
a
Monte Carlo modelMonte Carlo model
Oey & Clarke 1998
zero-age evolved
dmmdmmn
dNNdNNN
)(
)(
35.2
*2
***
upmax mm
CHEMICAL FEEDBACKCHEMICAL FEEDBACK
NucleosynthesisNucleosynthesis
Chemical evolutionChemical evolution
• MIXING : localMIXING : local
• HOMOGENIZATION : globalHOMOGENIZATION : global
• IN/OUT-FLOW : open boxIN/OUT-FLOW : open box
Simple Inhomogeneous Model Simple Inhomogeneous Model
Q: filling factor = const
n: generations
n
jjZZ
1
n
jnjj
QP
QQj
nP
jP
1
1 objects by occup.
0
ZNPZN j
n
jj
1ISM
ZNPDn
ZN j
n
jkkjk
n
j
1
,11
kDk 1
(Oey 2000, 2003)
Early times: Stochastic Inhomogeneous evolutionInhomogeneous evolution
*NL
2/33
LM
LRV
zRV
MZ z 1
)( 2 :2 dZZdZZf
Multi-generationMulti-generation
Parent metallicity distribution functionParent metallicity distribution function
Inhomogeneous evolution:Inhomogeneous evolution:
DispersionDispersion
Argast et al. (2000)-4.0 -3.0 -2.0 -4.0 -3.0 -2.0 [Fe/H][Fe/H]
Audouze & Silk (1995)
Thin disk: Oey & Bensby
McWilliam (1997)
Cayrel et al. (2005)
mtl-rich + old: high mtl-rich + old: high Q Q e.g.,e.g., BulgeBulge
mtl-poor + old: low mtl-poor + old: low Q Q e.g.,e.g., I Zw 18I Zw 18
n = 4
Q = 0.72
n = 24
Q = 0.72
n = 24
Q = 0.12
Evolution parameter: Evolution parameter: nQnQ
= nQ
2= nQ(1-Q)