The Evolution of Galaxies: The Evolution of Galaxies: From the Local Group From the Local Group to the Epoch of Reionization Reionization to the Epoch of Fabian Walter Fabian Walter National Radio Astronomy Observatory National Radio Astronomy Observatory
History of the Universe History of the Universe Cosmic ‘Dark Ages’ Outline no stars/quasars ß dwarf galaxies - building blocks? ß molecular gas - fuel for SF ß systems @ 0<z<5 ß systems in the EoR: z>6 Epoch of Reionization (EoR) ß outlook galaxies today
The Local Group The Local Group Bingelli 1994 Dwarfs: most numbers type of galaxies + low metallicity
Structure Formation Structure Formation high-z: small -> large structures today: still lots of low mass DM halos Moore et al. 1999 Ghigna et al. 1998
CDM Models vs. Local Group CDM Models vs. Local Group CDM simulations CDM simulations Structure of Local Group Structure of Local Group vs. Grebel 2002 Moore 1999
CDM Models vs. Local Group CDM Models vs. Local Group ‘missing missing ‘ satellite satellite problem’ ’ problem Moore 1999 -> challenge for both theoreticians and observers! -> challenge for both theoreticians and observers! searches did not find missing population. searches did not find missing population.
The Impact of SF The Impact of SF Mac Low & Ferrara 1999 ’? ? can blow-away explain ‘ ‘missing satellite problem missing satellite problem’ can blow-away explain
The Impact of SF: M82 The Impact of SF: M82 Ohyama et al. 2002 -> but can dwarf galaxies be ‘blown away’?
ISM <-> Star Formation ISM <-> Star Formation atomic hydrogen (HI) star formation molecular clouds trig. SF X-rays stars Halpha HI
LMC LMC Atomic Hydrogen in the LMC Kim et al. 1998
The Impact of SF: IC2574 SF: IC2574 The Impact of IC2574 Walter et al. 1998 Walter & Brinks 1999 ß v exp =25 kms -1 , age: 15x10 6 yr, E~10 53 erg trace SFH w/ HST ACS/WFC -> hole formed by central cluster (?)
The Impact of SF: Lowest Mass The Impact of SF: Lowest Mass SFR~0.001 M sun yr -1 Holmberg I M81 dwarf A Sculptor M HI =10 8 M sun M HI =10 7 M sun M HI ~10 4 M sun Ott, Walter et al. 2001 Carignan et al. 1998 transition objects? transition objects? circumstantial evidence: SF pushes gas out circumstantial evidence: SF pushes gas out need observations of hot gas phase (X-rays) need observations of hot gas phase (X-rays)
The Impact of SF: Dwarf Starburst Galaxies The Impact of SF: Dwarf Starburst Galaxies NGC 1569 NGC 3077 SFR~0.1 M sun yr -1 ß H a ß X-rays (Chandra) T~3x10 6 K r ~0.1 cm -3 D=0.5-1.5 kpc Ott, Martin & Walter 2003 Martin et al. 2002
Missing Satellites Missing Satellites Discrepancy w/ CDM model? Some cases show ‘blow-out’... ...but ‘blow-away’ ? still need to find transition objects -> deep optical/H a observations + spectroscopy -> XMM-Newton follow-up other ‘solutions’: problem w/ CDM simulations low-mass dark matter halos DARK
Mol. Gas & Millimeter Interferometers Mol. Gas & Millimeter Interferometers ß molecular gas: fuel for SF ß cold H 2 invisible -> use CO as tracer ß n [CO(n-(n-1))] = 115 GHz x n Fuel for SF in: ß spiral galaxies NRO NRO PdBI PdBI ß dwarf galaxies z=0 ß starburst galaxies ß mergers BIMA BIMA ß sources @ 2<z<5 high z ß sources in the EoR: z>6 VLA VLA OVRO OVRO
Spiral Galaxy: M51 Spiral Galaxy: M51 CO(1-0): OVRO + IRAM 30m Scoville et al. 2002, Aalto et al. 2000, Schinnerer et al. 2004
Dwarf Galaxy: IC10 Dwarf Galaxy: IC10 low-metallicity dwarf galaxy CO(1-0): OVRO res.: 12 pc, 0.6 kms -1 Walter et al. 2004
Starburst Galaxy: M82 Starburst Galaxy: M82 D ~ 3.5 Mpc CO(1-0): OVRO Ohyama et al. 2002 Walter, Weiss & Scoville 2002 ß Streamers with no SF, M H2 ~10 9 M sun ; M(disk:halo:streamers)=1:1:1 ß Molecular Gas in Outflow/Halo (line splitting)
Merger: Antennae Merger: Antennae CO(1-0): OVRO 3x10 9 M sun Whitmore et al. (1999) Wilson et al. (2000)
Conversion CO -> H 2 ß CO luminosities -> M H2 X CO = N(H 2 )/I CO -> M(H 2 ) M vir = M(H 2 ) ~ 240 * r[pc] * D v 2 [km/s] 1 ß Galaxy: X 20 cm -2 (K km s -1 ) –1 X CO = X X gal = 2.3 x 10 2.3 x 10 20 cm -2 (K km s -1 ) – CO = gal = (Strong et al. 1988) ß starburst galaxies/ULIRGs: X X CO ~0.3 X X gal gal CO ~0.3 (Downes & Solomon 1998, Weiss et al. 2000) ß low-metallicity dwarfs: X X CO = X X gal CO = gal (Walter et al. 2001, 2002; Bolatto et al. 2003)
X CO at low Metallicity ? NGC 4214 IC 10 NGC 6822 NGC 3077 finding consistent with Bolatto et al., Rosolowsky et al. (2003) X CO dependent on metallicity + starburst environment?
CO @ z=2.29 IRAS 10214+4724 at z=2.286 Brown & van den Bout 1991 Solomon, Downes & Radford 1992
MS1512-cB58 MS1512-cB58 Lyman Break galaxy at z=2.7 Baker et al. (2003) lensing factor: 31.8 M gas =6.6 10 9 M sun ; M dyn =1.0 10 10 M sun
4kpc SF Disk Around QSO 4kpc SF Disk Around QSO J2322+1922: Lensed QSO at z=4.12 Carilli et al. (2003) AGN: Keck R band CO(2-1): VLA 45 GHz Molecular Einstein Ring: RC cospatial w/ Gas, not AGN, r ~ 2kpc fi dust emission heated by SF not AGN, SFR~3000 M sun yr -1 (!)
SDSS Detection of High-z QSOs QSOs SDSS Detection of High-z end of cosmic reionization! ß ß Gunn Peterson effect: Gunn Peterson effect: -> universe significantly (>1%) -> universe significantly (>1%) neutral at z>6 neutral at z>6 Fan et al. 2003
WMAP CMB Polarization WMAP CMB Polarization WMAP polarization: WMAP polarization: universe ~50% neutral universe ~50% neutral at z=17+/-3 at z=17+/-3 Reionization Reionization complex (z~20-6); complex (z~20-6); not a phase transition not a phase transition Kogut et al. 2003
J1148+5251 J1148+5251 J1148+5251 at z=6.4 (@ end of EoR) Gunn Peterson trough Fan et al. 2003, White et al. 2003 ß z=6.42; age~870 Myr ß one of the first luminous sources ß M BH ~ 1-5 x 10 9 M sun (Willot et al. 2003) ß M dust ~ 10 8 M sun (Bertoldi et al. 2003) ß ~solar metallicity
The ‘Magic’ of MM/SUBMM 350 GHz 250 GHz
Redshift of Host Galaxy? Problem for CO search: e.g.: VLA 50 MHz = 300 km/s Dn/n =0.001 (bad!) Richards et al. 2002
Mol. Gas @ End of EoR CO(3-2) ß host galaxy(!) 46.6149 GHz ß molecular gas mass: M H2 = 2 x 10 10 M sun ß diameter: continuum 0.2”<D<1.5” (1”=5.6 kpc) ß mass in C and O: ~3x10 7 M sun enrichment started at z>8 (10 7 [100 M sun ] Pop III stars) Walter, Bertoldi, Carilli et al. 2003, Nature
Metals at z>6 n CO: C and O are abundant n metallicities: (super)solar! e.g., Pentericci et al. 2002, based on N V /C IV ratio n Fe/ a ratios ( a =Mg); no evolution of QSO metallicity e.g., Freudling et al. ‘03; Barth et al. ‘03; Maiolino et al. ‘03; Dietrich et al. ‘03 -> generations of stars must have formed at z>8 (SN Ia progenitors?, Pop III stars) optical studies: ß give abundances but not masses! ß trace AGN region only
CO @ z=6.42 (6-5) VL A (7-6) (3-2) PdBI ß M dyn = 2x10 10 M sun (sin i) -2 ; massive! (<-> CDM models, M- s ) ß z=6.419 (precise) ß T kin =100K, n H2 =10 5 cm -3 Walter et al. 2003 Bertoldi et al. 2003
M BH - s Relation at highest z? Gebhardt et al. 2000 Coevolution of BH and Bulge Shields, Gebhardt et al. 2003: M BH - s holds to z~3 1148+5251: M BH =3x10 9 M sun M dyn =M b >2x10 10 M sun ratio ~ 1:10 and not 1:1000 ? -> need to resolve disks (ALMA)
Cosmological Stromgren Sphere Around QSO ß CO: z=6.419 (optical high ionization lines can be off by 1000s km s -1 ) ß proximity effect: emission from 6.32<z<6.419 z=6.32 White et al. 2003 ß ionized sphere around QSO: R = 4.7 Mpc ß age of sphere: 10 7 yr Barkana & Loeb 2001 similar to formation timescale of central BH Walter et al. 2003
ALMA/EVLA Redshift Coverage Epoch of Reionization few QSOs known yet ALMA CO in J1148+5251 @ z=6.42 (E)VLA & GBT
ALMA ALMA is reality! ALMA is reality! n early science OP: 2007 n 64 antennas, 4 bands @ >5000 m alt.
Future Challenges n find missing dwarf galaxies - blown away? n EoR: find objects @ z>8 n are high masses in conflict w/ CDM models? M- s ? n rapid early metal production/enrichment?
SINGS: SIRTF Nearby Galaxy Survey SINGS: SIRTF Nearby Galaxy Survey SIRTF: Space Infrared Telescope Facility SINGS: 1 of 6 SIRTF ‘Legacy’ projects (512 hours), PI: R. Kennicutt SINGS Science Core ß IR imaging and spectroscopy of 75 nearby galaxies of all Hubble types, resolution: ~100pc ß SED templates for high-z galaxies...
Star Formation History of the Universe Star Formation History of the Universe n SINGS major goal: ‘calibrate’ SFR n SFR typically derived from UV and H a measurements n -> derive star formation history of the universe IR-submm selected z<1: decline z>1: constant? UV-visible selected Barger et al. 2000 n surveys: GOODS, GEMS, COSMOS, UDF; highest z: SDSS
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