Der Paul van der Werf Sterrewacht Leiden Starburst galaxies at low and high redshift ESO, Santiago April 2006

Paul van derder Werf

Sterrewacht Leiden

Starburst galaxies at low and high Starburst galaxies at low and high redshiftredshift

ESO, SantiagoESO, Santiago

April 2006April 2006

Starburst galaxies at low and high redshiftStarburst galaxies at low and high redshift 2

CreditsCredits

starbursts at low redshiftstarbursts at low redshift Leonie SnijdersLeonie Snijders (VISIR) (VISIR) Liesbeth Vermaas (SINFONI)Liesbeth Vermaas (SINFONI) Kate Isaak Kate Isaak (Cardiff)(Cardiff) Padelis Papadopoulos Padelis Papadopoulos (ETH Z(ETH Züürich)rich)

starbursts at high redshiftstarbursts at high redshift Kirsten Kraiberg KnudsenKirsten Kraiberg Knudsen (PhD October 2004) (PhD October 2004) Tracy Webb (McGill University, Montreal)Tracy Webb (McGill University, Montreal) Lottie van StarkenburgLottie van Starkenburg (SINFONI) (SINFONI)

and the FIRES team:and the FIRES team:

Marijn FranxMarijn Franx Pieter van Dokkum (Yale)Pieter van Dokkum (Yale) Ivo Labbé (Carnegie)Ivo Labbé (Carnegie) Greg Rudnick (NOAO)Greg Rudnick (NOAO) Hans-Walter Rix (MPIA)Hans-Walter Rix (MPIA) Mariska KriekMariska Kriek Natascha Förster Schreiber (MPE)Natascha Förster Schreiber (MPE) Alan Moorwood (ESO)Alan Moorwood (ESO)


« The stellar systems are scattered through space as far as telescopes can penetrate. We find them smaller and fainter, in constantly increasing numbers, and we knowthat we are reaching out into space, until, with the faintest nebulae than can be detected with greatest telescopes, we arrive at the frontiers of the knownUniverse. »

Edwin Hubble, The Realm of the Nebulae (1936)


What is a starburst galaxy?What is a starburst galaxy?

correction factor for mass return from stars

A starburst galaxy is a galaxy with such a high star formation rate that it will turn all of its gas into stars in tb << tHubble

2

2

9H

1

H 10b

2.5 10

1 yr

2 2 10 yrs

M M

M M

Mt

M

2H gas0.5M M

Milky Way:Milky Way:

gradual buildup of diskgradual buildup of disk


A luminous infrared galaxy: the AntennaeA luminous infrared galaxy: the Antennae

Crossing orbits giveCrossing orbits give gas concentration gas concentration in in interaction zoneinteraction zone

Intense obscured Intense obscured

star formation in star formation in overlap regionoverlap region

Most intense star Most intense star formation is formation is obscuredobscured

(Webb, Snijders & Van der Werf , in preparation)(Webb, Snijders & Van der Werf , in preparation)

SCUBA 850 SCUBA 850 mm

11FIR

1

3 10

30 yr

L L

M M


Arp220Arp220

An ultraluminous infrared galaxy: Arp220An ultraluminous infrared galaxy: Arp220

12FIR

1

1.5 10

150 yr

L L

M M


Starformation in ULIRGsStarformation in ULIRGs

correction factor for mass return from stars

2

2

10H

1

H 8b

1.6 10

150 yr

2 2 10 yrs

M M

M M

Mt

M

Arp220:Arp220:

NB: NB: ttbb few 10 few 1088 yrs yrs merger timescale merger timescale dynamical timescaledynamical timescale (crossing/rotation time)(crossing/rotation time) free-fall time protogalaxy?free-fall time protogalaxy?

Such high SFRs can build up an Such high SFRs can build up an entire galaxy in entire galaxy in t t << << ttHubbleHubble relation to galaxy relation to galaxy formation?formation?


Simple-minded estimate of Simple-minded estimate of ""maximum star formation ratemaximum star formation rate""

initial starburst – rapid formation of bulk of the stellar population

gasmax gas

ff

22 3

4selfgravitating sphere:

MM M G

t

RG

In the absence of external pressure, the maximum star formation rate occurs In the absence of external pressure, the maximum star formation rate occurs when a gas mass is turned into stars on the free-fall timescale.when a gas mass is turned into stars on the free-fall timescale.

formation of spheroids?formation of spheroids?

31

max 100 yr100 km/s

M M

Implication: Implication: high SFRs are found in the most massive galaxieshigh SFRs are found in the most massive galaxies


Do “maximum starburst” galaxies exist?Do “maximum starburst” galaxies exist?

maximumstarbursts

normal galaxies

luminous IR galaxies(LIRGs)

(Kennicutt 1998)

ultraluminous IR galaxies(ULIRGs)


ULIRGs as “maximum starbursts”ULIRGs as “maximum starbursts”

10bol1

12bol max

10yr

ULIRGs ( 10 ) have !

L MA

L M

L L M M

(cf., 30–50% for normal spirals)(cf., 30–50% for normal spirals)

ULI

RG

sU

LIR

Gs

(IMF parameters) 1A f

12 FIR

bol

At 10 is 90%L

L LL


Starformation efficiencyStarformation efficiency

Starbursts cannotStarbursts cannot be simply scaled be simply scaled up.up.

More intense More intense starbursts starbursts are also more are also more efficientefficient with their fuel.with their fuel. (Gao & Solomon 2001)

LLIRIR SFR SFR

LLIRIR//LLCOCO

SFR/SFR/MMHH22

SFESFE

2

1FIR

H

1

1

1

1

ULIRGs: 100

Milky Way: 1.5

Galactic GMCs: 1.8

OMC-1: 54

Orion BN-KL: 400

LL M

M

L M

L M

L M

L M


Role of dense gasRole of dense gas

More dense gas means more efficient star formation.More dense gas means more efficient star formation.

(Gao & Solomon 2001)

LLHCNHCN//LLCOCO mass fraction of mass fraction of densedense gas gas

LLIRIR//LLCOCO

SFR/SFR/MMHH22

SFESFE


NGC 4038/4039

Orion (M42) 30 Doradus

NGC 4038/4039 detail

Superstarclusters:Superstarclusters:does size matter?does size matter?

NGC4038/4039 cluster: NGC4038/4039 cluster:

100 pc100 pc

Orion: Orion: 1.5 pc 1.5 pc


Superstarclusters: densitiesSuperstarclusters: densities

ObjecObjectt

dd

[pc][pc]MM

[[MM]]

[[MM pc pc——

33]]

in 4.5pcin 4.5pc

nnHH

[cm[cm—3—3]]

in in 4.5pc4.5pc

[W99][W99]22

100100 2∙102∙1066

52005200 1.6∙11.6∙10055

R136R136 1010 33∙10∙1044

8080 25002500

M42M42 22 18001800 55 200200


The Antennae with Spitzer and VISIRThe Antennae with Spitzer and VISIR

IRAC/SpitzerIRAC/Spitzer(Wang (Wang et al.et al., 2004), 2004)

[NeII] 12.8 [NeII] 12.8 mmESO/VLT VISIRESO/VLT VISIR(Snijders (Snijders et al.et al., , in prepin prep.).)

contours: contours: dust continuumdust continuum


Probing dense molecular gasProbing dense molecular gas

LineLine TTexex

[K][K]

nncritcrit

[cm[cm—3—3]]

CO 1CO 100 5.55.5 1.7∙101.7∙1033

CO 4CO 433 5555 8.0∙108.0∙1044

CO 6CO 655 116116 2.5∙102.5∙1055

HCN 1HCN 100 4.34.3 1.4∙101.4∙1055

HCN 4HCN 433 4242 5.5∙105.5∙1066

molecular gasmolecular gas

densedense molecular gas molecular gas

temperaturetemperature of dense gas of dense gas


Dense gas in the ULIRG Mrk231Dense gas in the ULIRG Mrk231

RxW/JCMTRxW/JCMT(Papadopoulos, Isaak & Van der Werf 2006)(Papadopoulos, Isaak & Van der Werf 2006)

(Papadopoulos & Van der Werf 2001)(Papadopoulos & Van der Werf 2001)

Mrk231 CO 6Mrk231 CO 65 and 45 and 433


Again: dense gas in Mrk231Again: dense gas in Mrk231

RxB3/JCMTRxB3/JCMT(Papadopoulos, Isaak & Van der Werf 2006)(Papadopoulos, Isaak & Van der Werf 2006)

Mrk231 CO 3Mrk231 CO 32 and 102 and 10HCN 4HCN 433


Combine these data with CO 1Combine these data with CO 10, 20, 21 and 1 and 1313CO 2CO 21 (upper 1 (upper limit):limit):

no model reproduces all CO linesno model reproduces all CO lines::

CO 4CO 43/63/65 and CO 15 and CO 10/20/21/31/32 probe different gas 2 probe different gas phases.phases.

diffuse phasediffuse phase: : T T 50—85 K and 50—85 K and n n 300—10 300—1033 cm cm—3—3,,

dense phasedense phase: : T T 50—65 K and 50—65 K and n n 10 1044 cm cm—3—3..

TotalTotal mass of molecular gas from CO: mass of molecular gas from CO:

M M 3.5∙10 3.5∙1010 10 MM (or up to a factor 4—5 lower). (or up to a factor 4—5 lower).

Mass of Mass of dense dense molecular gas from HCN:molecular gas from HCN:

M M 1.5—3.5∙10 1.5—3.5∙1010 10 MM..

Almost all molecular gas in Mrk231 is dense.Almost all molecular gas in Mrk231 is dense.

Two phases of molecular gasTwo phases of molecular gas


ULIRGs and galaxy formationULIRGs and galaxy formation

Locally, ULIRGs are energetically unimportantLocally, ULIRGs are energetically unimportant: : contribute only 2% of local bolometric energy densitycontribute only 2% of local bolometric energy density

How important are ULIRGs at high z? How important are ULIRGs at high z? observe redshifted far-IR emissionobserve redshifted far-IR emission in submillimetre in submillimetre with JCMT/SCUBAwith JCMT/SCUBA

Local ULIRGs almost always have a hidden AGNLocal ULIRGs almost always have a hidden AGN: : causal link with the extreme starburst?causal link with the extreme starburst?

Are high-Are high-zz ULIRGs the sites of the coeval formation of spheroids and ULIRGs the sites of the coeval formation of spheroids and supermassive black holes?supermassive black holes? question for the coming decadequestion for the coming decade


MicrowaveBackground IR/Optical

Background

X-RayBackground

Big BangBig Bang

Stars+BlackHolesStars+BlackHoles

AGNAGN

1mm 1m 1nm

(Puget et al. 1996, Hauser et al. 1998Fixsen et al. 1998)

Cosmic energy densityCosmic energy density


Is obscured star formation important?Is obscured star formation important?

Direct starlight:Direct starlight:

Far-IR Far-IR background:background:

II = 1.7 = 1.7 .. 10 10-5-5 ergerg//ss//cmcm22//srsr

II = 3.1 = 3.1 .. 10 10-5-5 ergerg//ss//cmcm22//srsr

Obscured star Obscured star formation formation dominates.dominates.


Submillimetre cosmologySubmillimetre cosmology

Submm samples have high Submm samples have high proportion of high-proportion of high-zz galaxies galaxies

Galaxies up to Galaxies up to z z 10 10 detectabledetectable

Brightness-limited Brightness-limited volume-limitedvolume-limited

Luminosities without precise Luminosities without precise redshiftsredshifts

Sources do not fade much Sources do not fade much from from zz=1 to 10=1 to 10

Deeper surveys probe Deeper surveys probe fainter galaxies, not higher fainter galaxies, not higher zz

LargeLarge negativenegative kk-correction-correction::


Counts and backgroundsCounts and backgrounds

Submm background comesSubmm background comesfrom small number offrom small number of

(ultra)luminous galaxies(ultra)luminous galaxies

Resolved background atResolved background at 850850m:m: 25% down to 2 mJy25% down to 2 mJy

Connection to other Connection to other populations at fainter flux populations at fainter flux levels.levels.Lensing can probe these.Lensing can probe these.


SCUBA/JCMT lensed galaxy surveySCUBA/JCMT lensed galaxy survey

Knudsen PhD thesisKnudsen PhD thesisVan der WerfVan der Werf

12 gravitationally lensing 12 gravitationally lensing clustersclusters

1 blank field (NTT Deep 1 blank field (NTT Deep Field)Field)

Survey area 72 arcminSurvey area 72 arcmin22

Deepest fields are Deepest fields are confusion-limited (2 mJy)confusion-limited (2 mJy)

55 sources detected at 850 55 sources detected at 850 mm


Faint submillimetre source counts Faint submillimetre source counts

Counts imply strong Counts imply strong evolutionevolution

First time the First time the faintfaint submm submm population is substantially population is substantially probedprobed

Connection with optical Connection with optical populationpopulation

TurnoverTurnover in counts detected in counts detected for the for the first timefirst time((Knudsen, Van der WerfKnudsen, Van der Werf & Kneib, & Kneib, in prep.in prep.))


Submillimetre source counts Submillimetre source counts and evolutionand evolution

Counts + background implyCounts + background implypure luminositypure luminosity evolution evolutionproportional to (1+proportional to (1+zz))33

luminosityluminosity evolution: evolution: LL (1+ (1+zz))pp

densitydensity evolution: evolution: NN (1+ (1+zz))qq


Submm galaxies in Submm galaxies in the NTT Deep Fieldthe NTT Deep Field

Not an ERO (?)Not an ERO (?)

EROERO

(Knudsen (Knudsen et al.et al. in preparation) in preparation)


FIRES: Faint Infrared Extragalactic SurveyFIRES: Faint Infrared Extragalactic Survey

ISAAC/AntuISAAC/AntuHDF-S: Labbé HDF-S: Labbé et alet al., 2003., 2003MS1054—03: FMS1054—03: Föörster Schreiber rster Schreiber et alet al., 2006., 2006



FIRES allows better mass selectionFIRES allows better mass selection

FIRES allows selection of high-FIRES allows selection of high-zz galaxies in the rest-frame galaxies in the rest-frame VV-band-band much closer to a mass-selection than rest-frame UVmuch closer to a mass-selection than rest-frame UV a new class of high-a new class of high-zz galaxies: galaxies: Distant Red Galaxies (DRGs)Distant Red Galaxies (DRGs)

I814

Ks

the 6 most massive z 3 galaxies in the HDF-S


Rest-frame SEDs: Lyman break galaxiesRest-frame SEDs: Lyman break galaxies


Rest-frame SEDs: distant red galaxiesRest-frame SEDs: distant red galaxies

(F(Föörster Schreiber rster Schreiber et al.,et al., 2004) 2004)


Selection of distant red galaxiesSelection of distant red galaxies

(Franx (Franx et al.et al., 2003), 2003)


DRGs are (mostly) star forming galaxiesDRGs are (mostly) star forming galaxies

star formation star formation ratesrates

> 100 > 100 MM yryr—1—1(Van Dokkum (Van Dokkum et al.,et al., 2004) 2004)


SCUBA observations of MS1054SCUBA observations of MS1054–03–03

M1383M1383SS850850 = 5 mJy = 5 mJy


Submm galaxies and DRGsSubmm galaxies and DRGs

Lyman Break Galaxies have no detectable submm emission even afterLyman Break Galaxies have no detectable submm emission even after massive source stackingmassive source stacking

Distant Red Galaxies are massive and have high SFRsDistant Red Galaxies are massive and have high SFRs

DRGs: 3 arcminDRGs: 3 arcmin–2–2 for for KK<22.5<22.5 same source density as submm galaxies with >0.8 mJy at 850 same source density as submm galaxies with >0.8 mJy at 850 mm

1 FIRES field observed with SCUBA: 1 DRG detected directly (5 mJy)1 FIRES field observed with SCUBA: 1 DRG detected directly (5 mJy)

connection between sub-mJy submm galaxies and DRGs?connection between sub-mJy submm galaxies and DRGs?


Stacking DRGsStacking DRGs

DRGs, EROsDRGs, EROs

random positionsrandom positions

DRGs:DRGs:SS850850 = 1.11 = 1.11 0.28 mJy 0.28 mJy

(Knudsen (Knudsen et al.et al., 2005), 2005)


Breaking the confusion barrier: Breaking the confusion barrier: gravitational lensesgravitational lenses

A2218A2218


A2218: SCUBA 850 A2218: SCUBA 850 mm


The submm triple behind A2218The submm triple behind A2218

Triple image, Triple image, zz=2.515=2.515

Magnification in total factor 40Magnification in total factor 40

Intrinsic 850 Intrinsic 850 m flux: 0.8 mJym flux: 0.8 mJy

Redshifted HRedshifted H:: strong star formationstrong star formation

J–KJ–K=2.7: =2.7: Distant Red GalaxyDistant Red Galaxy

(Kneib (Kneib et al.et al., 2004a), 2004a)


CO 3CO 3–2 detection of the–2 detection of the submm triple submm triple

Detected both at Owens Valley and Plateau de BureDetected both at Owens Valley and Plateau de BureCO line width CO line width less massive than bright SMGs but less massive than bright SMGs but comparable to DRGscomparable to DRGs

(Sheth (Sheth et al.,et al., 2004; 2004; Kneib Kneib et alet al., 2005b)., 2005b)


Conclusions and outlook: low Conclusions and outlook: low zz

Gas Gas densitydensity is crucial in is crucial in determining starburstdetermining starburst properties; also related properties; also related to to depth of potential well?depth of potential well?

Luminous starbursts tend Luminous starbursts tend to to have both high have both high LL//MM and and high high MM

Molecular lines probe Molecular lines probe density/temperature density/temperature structurestructure

The future: The future: SINFONI+LGSSINFONI+LGS, , APEXAPEX, HIFI/Herschel, , HIFI/Herschel, ALMAALMA


Conclusions and outlook: high Conclusions and outlook: high zz

Starbursts are a key process in galaxy evolutionStarbursts are a key process in galaxy evolution

We are looking back towards a strongly obscured universe,We are looking back towards a strongly obscured universe, energetically dominated by dusty starburstsenergetically dominated by dusty starbursts

DRGs are massive and have high SFRs; as a population they are atDRGs are massive and have high SFRs; as a population they are at least as important as LBGs for cosmic mass budget and SFRleast as important as LBGs for cosmic mass budget and SFR

Connection between DRGs and faint submm galaxiesConnection between DRGs and faint submm galaxies

The future: The future: SCUBA2SCUBA2, ALMA, HAWK-I, JWST, ELT, ALMA, HAWK-I, JWST, ELT


To coldly go…: SCUBA-2To coldly go…: SCUBA-2 SCUBA-2 will bring rectangular SCUBA-2 will bring rectangular array array imaging to submm astronomyimaging to submm astronomy

8 408 4032 sub-arrays – 4 at 850 32 sub-arrays – 4 at 850 m, m, 4 at 450 4 at 450 mm

Mapping speed unequalledMapping speed unequalled

Operational mid-2007Operational mid-2007

Legacy programs defined:Legacy programs defined: Cosmological surveyCosmological survey Full Galactic plane surveyFull Galactic plane survey Full Gould’s Belt surveyFull Gould’s Belt survey Shallow “all-sky” surveyShallow “all-sky” survey Unbiased debris disk Unbiased debris disk surveysurvey


SCUBA-2 Cosmology Legacy SurveySCUBA-2 Cosmology Legacy Survey 4 PIs: Dunlop, Halpern, 4 PIs: Dunlop, Halpern, Smail, Smail, Van der WerfVan der Werf

Large survey (20 degLarge survey (20 deg22) at ) at 850 850 m, m, deep survey at 450 deep survey at 450 m (0.5 m (0.5 degdeg22))

450 450 m survey will resolve m survey will resolve full full submm background and submm background and detect all detect all LIRGs in the survey area LIRGs in the survey area out to z=2 out to z=2 (ULIRGs out to z=4)(ULIRGs out to z=4)

Connection with other Connection with other populations: populations: optical, near-IR, X-ray, optical, near-IR, X-ray, radio,…radio,…

Time allocation Time allocation 102 good 102 good nightsnights (including (including 50% of the best 50% of the best weather weather until mid-2009until mid-2009))

SCUBA-2 field-of-view

1 deg1 deg22 field, will be mapped to confusion field, will be mapped to confusion limit in 23 hours by SCUBA-2 at 850 limit in 23 hours by SCUBA-2 at 850 mm


« We are, by definition, in the very center of the observable region. We know our immediate neighborhood rather intimately. With increasing distance, our knowledge fades, and fades rapidly. Eventually, we reach the dim boundary, the utmost limits of ourTelescopes. There, we measure shadows, and we search amongghostly errors of measurement for landmarks that are scarcelymore substantial.

The search will continue. Not until the empirical resources areexhausted, need we pass on the dreamy realms of speculation. »

Edwin Hubble, The Realm of the Nebulae (1936)

Documents

Der Paul van der Werf Sterrewacht Leiden Starburst galaxies at low and high redshift ESO, Santiago April 2006