desika narayanan evla conference the formation and evolution of smgs: a (mostly) panchromatic view...
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Desika Narayanan EVLA Conference
The Formation and Evolution of SMGs:A (mostly) Panchromatic View
Desika Narayanan Harvard-Smithsonian Center for Astrophysics
The Team:
T.J. CoxLars HernquistPatrik Jonsson
Chris HaywardJosh Younger
Desika Narayanan EVLA Conference
Discovery History
Barger et al., Hughes et al.
Desika Narayanan EVLA Conference
The Incredible Fluxes of SMGs:
• Median Redshift z~2.4 (Chapman et al 2004)
• Selected at S850 > 5 mJy, seen up to S850 ~ 20 mJy
z~2.4~mJy source
(NED; Benford 1999)
Desika Narayanan EVLA Conference
Where We’re at with SMGs:
• Median Redshift z~2.4 (peak of cosmic BH and SFR activity)
Chapman et al 2004 - though see recent z>4 detections by J. Younger et al.
• LIR > 1013 L
• SFR ~ 1000-3000 M/yr
• Huge Masses:– DM: 5x1012 M (Blain et al. 2004) – H2: Gas rich ~1010 M(Greve et al., Tacconi et al.)
– Stellar: ~1011 M (Swinbank et al., Lonsdale et al.)
Similar to z~2 QSOs
Desika Narayanan EVLA Conference
Where We’re at with SMGs:
• Median Redshift z~2.4 (Chapman et al 2004)
• Selected at S850 > 5 mJy, seen up to S850 ~ 20 mJy
• Huge Masses:– DM: 5x1012 M (Blain et al. 2004) – H2: Gas rich ~1010 M(Greve et al., Tacconi et al.)
– Stellar: ~1011 M (Swinbank et al., Lonsdale et al.)
– SFR~ 2000 M/yr
SMGs are the most luminous,
heavily star forming galaxies at
the epoch of peak galaxy
formation
Desika Narayanan EVLA Conference
The Theoretical Challenge (how do we catch up to the observers?):
• What is a physical model for SMGs (how do we form them)?
• How do they fit in an evolutionary scenario for hierarchical galaxy formation? (aka, how do we connect
them to quasars?)
Desika Narayanan EVLA Conference
Clues for the Modelers: Physical Parameters
Merger? Disks?
+
massive galaxies (~few x 1011 M in stars)
= 5-20 mJy SMGs?
Lonsdale et al. 2008
Tacconi et al. 2008
Desika Narayanan EVLA Conference
Clues for the Modelers:
• Huge CO Line Widths:
(800 km/s : (maybe) ~ twice z~2 QSOs) (Greve et al. 2004, Carilli & Wang 2006)
•Off MBH-M* Relation?(Alexander et al. 2008)
Desika Narayanan EVLA Conference
The Theoretical Challenge (how do we catch up to the observers?):
• What is a physical model for SMGs (how do we form them)?
• How do they fit in an evolutionary scenario for hierarchical galaxy formation?
Desika Narayanan EVLA Conference
The Theoretical Challenge: Forming SMGs
• What is a physical model for SMGs (how do we form them)?
SAMs:Flat IMF: dn/dln(m) ~ m
(Baugh et al. 2004, Swinbank et al. 2008)
Numerical Models:Merger models, diffuse ISM
(Chakrabarti et al. 2006)
S850--->
S85
0---
>Time--->
Desika Narayanan EVLA Conference
GADGET (SPH) + SUNRISE (IR)+ Turtlebeach (Molecular Line)
Physics Included in Hydrodynamics:-Full numerics: DM, Gas, Stars and BHs-Multi-phase McKee-Ostriker ISM-Star formation follows KS relations-BH growth and associated AGN feedback-Supernovae pressurization of ISM
-Virial Properties of Galaxy disks scaled to z~3-Mergers and Isolated disks simulated-Halo Masses: 1-5 x 1012 M
Go to http://www.cfa.harvard.edu/~dnarayan/Movies/ for the movies in the presentation
Desika Narayanan EVLA Conference
Narayanan et al. 2008
Desika Narayanan EVLA Conference
GADGET (SPH) + SUNRISE (IR) + Turtlebeach (Molecular Line)
GMC
Diffuse ISM
Physics Included in Monte Carlo IR RT:-IR transfer of stellar and AGN spectrum(starburst 99 for stars and Hopkins+ 07 for AGN)
-dust radiative equilibrium
-Kroupa IMF, MW Dust to Metals (0.4)
-Stellar Clusters surrounded by placental GMCs (covering fraction is free parameter; fcover=0.3-1 measured in ULIRGs)
Desika Narayanan EVLA Conference
GADGET (SPH) + SUNRISE (IR) + Turtlebeach (Molecular Line)
Narayanan et al. (2008)
Physics Included in Monte Carlo CO RT
-Mass spectrum of GMCs included as SISs
-Molecular statistical equilibrium (collisions and radiation)
-Pressure-driven H2 formation/destruction (Blitz & Rosolowsky 2006)
-Milky Way Abundances for CO
coco
co
co
co
co
co
co
Desika Narayanan EVLA Conference
SMGs are Major Mergers at z~2
Narayanan, Hayward, Cox et al. in prep.Narayanan, Hayward, Cox, Younger et al. submitted
Opacity dominated by
birth clouds during
starburst
Opacity dominated by
diffuse dust during inspiral
Desika Narayanan EVLA Conference
SMGs are Major Mergers at z~2
Narayanan, Hayward, Cox et al. in prep.Narayanan, Hayward, Cox, Younger et al. submitted.
Opacity dominated by
birth clouds during
starburst
Opacity dominated by
diffuse dust during inspiral
1. Low luminosity (~5 mJy) SMGs are smaller scale (~100-200 M/yr)starbursts.
2. The most luminous (~20 mJy) SMGs are “maximal” high mass starbursts duringfinal coalesence.
3. Individual Spirals will have trouble reproducing anything except very low luminosity SMGs.
Desika Narayanan EVLA Conference
Model SED at z=2: Matching Observations
Pope et al. (2006) Kovacs et al. (2006)
Narayanan, Hayward, Cox, Younger et al. submitted
Desika Narayanan EVLA Conference
The Theoretical Challenge:
• What is a physical model for SMGs (how do we form them)?
• How do they fit in an evolutionary scenario for hierarchical galaxy formation? Are SMGs and quasars related?
Desika Narayanan EVLA Conference
The life of an SMG: Sub-mm, CO and B-band evolution
Narayanan, Hayward, Cox et al. in prep.
√2
Coppin et al. 2008
virial
= 225 km/s * 2.354 =
530 km/s FWHM
Sub-mm Flux
B-band Flux
Narayanan, Cox, Hayward, Younger et al. in prep.
escape
~ 225 km/s * 2.354 * √2 =
750 km/s FWHM
Desika Narayanan EVLA Conference
The Connection between SMGs and QSOs
Narayanan, Hayward, Cox et al. in prep.
Sub-mm Flux
B-band Flux
Time Scale between
peak SMG phase and
peak QSO phase: ~50 Myr -
though note tons of overlap
Desika Narayanan EVLA Conference
The MBH-M* Relation in SMGs and Quasars: Observed
SMGs
Alexander et al.
Quasars
Shileds et al.
Desika Narayanan EVLA Conference
The MBH-M* Relation in SMGs and Quasars: Modeled
Time
Desika Narayanan EVLA Conference
The Trip Toward the Magorrian Relation: SMGs
Observations (Alexander
et al.)
Models
(DN, Hayward, Cox, Younger et al.)
Desika Narayanan EVLA Conference
Are High-z QSOs on the MBH-M* relation ?
Quasars at z~2
Shields et al. 2006
Quasars at z~6
Walter, Carilli et al.
~120 km/s
Desika Narayanan EVLA Conference
CO FWHM-QSO Luminosity Relation
Optically Luminous LOSs have small CO FWHMs because of molecular disk formation
Narayanan, Li et al. (2008)
Desika Narayanan EVLA Conference
Line widths of lower luminosity z~6 quasars Are observed to be broader (~600 km/s), consistent with large halo mases
Carilli et al. (2007)Maiolino et al. (2007)
Desika Narayanan EVLA Conference
Potential Contribution from the eVLA: Morphologies of SMGs(does our merger-driven scenario work in real life?)
Sub-mm flux
Desika Narayanan EVLA Conference
Contribution from the EVLA: True Line Width Distribution of QSOs
Sub-mm flux
Desika Narayanan EVLA Conference
Conclusions• Merger-driven model can reproduce S850 5-20 mJy using only
observationally motivated physical parameters
• Sub-mm duty cycles, SEDs, CO fluxes and line widths naturally reproduced in a merger-driven model
• SMGs evolve naturally into QSOs and then onto Magorrian Relation
• Quasars may be selected to have face-on molecular disks
Desika Narayanan EVLA Conference
QSOs may have preferentially face-on disks
Narayanan, Hayward, Cox et al. in prep.
Sub-mm Flux
Coppin et al. 2008
Narayanan et al. 2008
QSOs
SMGs
Desika Narayanan EVLA Conference
GADGET (SPH) + SUNRISE (IR) + Turtlebeach (Molecular Line)
GMC
Diffuse ISM
Physics Included in Monte Carlo IR RT:-IR transfer of stellar and AGN spectrum(starburst 99 for stars and Hopkins+ 07 for AGN)
-dust radiative equilibrium
-Kroupa iMF, MW Dust to Gas
-Stellar Clusters surrounded by placental GMCs (covering fraction is free parameter)
z = 2.5 SED input
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