The Evolution of Gas in Galaxies Philip Lah

The Evolution of Gas in Galaxies Philip Lah End of Thesis Colloquium

Chair of Supervisory Panel: Frank Briggs (ANU) Supervisory Panel: Jayaram Chengalur (NCRA) Matthew Colless (AAO) Roberto De Propris (CTIO) Erwin De Blok (UCT) With Assistance From: Michael Pracy (ANU)

Talk Outline Introduction • HI 21 -cm emission, galaxies and star formation • the cosmic star formation rate density and the cosmic HI density • high redshift HI 21 -cm emssion observations and the coadding technique Current Observations with the HI coadding technique • HI in star-forming galaxies at z = 0. 24 • HI in galaxies around Abell 370, a galaxy cluster at z = 0. 37 Future Observations with SKA pathfinders • using ASKAP and Wiggle. Z • using Meer. KAT and z. COSMOS • ideas on the evolution of gas in galaxies

Talk Outline Introduction • HI 21 -cm emission, galaxies and star formation • the cosmic star formation rate density and the cosmic HI density • high redshift HI 21 -cm emssion observations and the coadding technique Current Observations with the HI coadding technique • HI in star-forming galaxies at z = 0. 24 • HI in galaxies around Abell 370, a galaxy cluster at z = 0. 37 Future Observations with SKA pathfinders • using ASKAP and Wiggle. Z • using Meer. KAT and z. COSMOS • ideas on the evolution of gas in galaxies

Talk Outline Introduction • HI 21 -cm emission, galaxies and star formation • the cosmic star formation rate density and the cosmic HI density • high redshift HI 21 -cm emssion observations and the coadding technique Current Observations with the HI coadding technique • HI in star-forming galaxies at z = 0. 24 • HI in galaxies around Abell 370, a galaxy cluster at z = 0. 37 Future Observations with SKA pathfinders • using ASKAP and Wiggle. Z • using Meer. KAT and z. COSMOS • ideas on the evolution of gas in galaxies

HI 21 -cm Emission

Neutral atomic hydrogen creates 21 -cm radiation proton electron

Neutral atomic hydrogen creates 21 -cm radiation

Neutral atomic hydrogen creates 21 cm radiation

Neutral atomic hydrogen creates 21 -cm radiation

Neutral atomic hydrogen creates 21 -cm radiation photon

Neutral atomic hydrogen creates 21 -cm radiation decay half life ~10 million years (3 1014 s)

HI 21 -cm Emission From Galaxies

Galaxy M 33: optical

Galaxy M 33: HI 21 -cm emission

Galaxy M 33: optical and HI

Galaxy M 33: optical

HI Gas and Star Formation neutral atomic hydrogen gas cloud (HI) molecular gas cloud (H 2) star formation

Galaxy HI mass vs Star Formation Rate

Galaxy HI Mass vs Star Formation Rate HIPASS & IRAS data z~0 Doyle & Drinkwater 2006

The Star Formation Rate Density of the Universe

Star Formation Rate Density Evolution Compilation by Hopkins 2004

The HI Gas Density of the Universe

HI Gas Density Evolution Not a log scale

HI Gas Density Evolution Lah et al. 2007 coadded HI 21 cm Prochaska et al. 2005 & 2009 DLAs Zwaan et al. 2005 HIPASS HI 21 cm Rao et al. 2006 DLAs from Mg. II absorption

HI 21 cm Emission at High Redshift

HI 21 cm emission at z > 0. 1 Zwaan et al. 2001 WSRT 200 hours

HI 21 cm emission at z > 0. 1 Verheijen et al. 2004 VLA 80 hours

HI 21 cm emission at z > 0. 1 Verheijen et al. 2007 WSRT 180 & 240 hours

HI 21 cm emission at z > 0. 1 Catinella et al. 2007 Arecibo 2 -6 hours per galaxy

HI 21 cm emission at z > 0. 1 Lah et al. 2007 coadded GMRT 81 hours Lah et al. 2009 coadded GMRT 63 hours

Coadding HI signals

Coadding HI signals Radio Data Cube y c n e u ft q i e h s Fr d e r I H DEC RA

Coadding HI signals Radio Data Cube y c n e u ft q i e h s Fr d e r I H DEC positions of optical galaxies RA

flux Coadding HI signals frequency

z 1 Coadding HI signals flux z 2 z 3 frequency z 1, z 2 & z 3 optical redshifts of galaxies

Coadding HI signals z 1 flux z 2 z 3 velocity z 1, z 2 & z 3 optical redshifts of galaxies

Coadding HI signals z 1 flux z 2 Coadded HI signal z 3 velocity z 1, z 2 & z 3 optical redshifts of galaxies

Current Observations HI coadding

Giant Metrewave Radio Telescope

Giant Metrewave Radio Telescope

Giant Metrewave Radio Telescope

Giant Metrewave Radio Telescope

Anglo-Australian Telescope

2 d. F/AAOmega instrument multi-object, fibre fed spectrograph

The Fujita galaxies H emission galaxies at z = 0. 24

The Fujita Galaxies Subaru Field 24’ × 30’ narrow band imaging Hα emission at z = 0. 24 look-back time ~3 billion years (Fujita et al. 2003, Ap. JL, 586, L 115) DEC 348 Fujita galaxies 121 redshifts using AAT GMRT ~48 hours on field RA

Star Formation Rate Density Evolution Compilation by Hopkins 2004

Star Formation Rate Density Evolution Fujita et al. 2003 value Compilation by Hopkins 2004

Coadded HI Spectrum

Fujita galaxies coadded HI spectrum raw HI spectrum allusing 121 redshifts - weighted average

Fujita galaxies coadded HI spectrum raw HI spectrum allusing 121 redshifts - weighted average binned MHI = (2. 26 ± 0. 90) × 109 M

The HI Gas Density of the Universe

HI Gas Density Evolution Lah et al. 2007 coadded HI 21 cm

Galaxy HI mass vs Star Formation Rate

Galaxy HI Mass vs Star Formation Rate HIPASS & IRAS data z~0 Doyle & Drinkwater 2006

HI Mass vs Star Formation Rate at z = 0. 24 all 121 galaxies line from Doyle & Drinkwater 2006

HI Mass vs Star Formation Rate at z = 0. 24 42 bright L(Hα) galaxies line from Doyle & Drinkwater 2006 42 medium L(Hα) galaxies 37 faint L(Hα) galaxies

Abell 370 a galaxy cluster at z = 0. 37

Galaxy Clusters and HI gas

Galaxy Cluster: Coma

Nearby Galaxy Clusters Are Deficient in HI Gas

HI Deficiency in Clusters Def. HI = log(MHI exp. / MHI obs) Def. HI = 1 is 10% of expected HI gas expected gas estimate based on optical diameter and Hubble type interactions between galaxies and interactions with the inter-cluster medium removes the gas from the galaxies Gavazzi et al. 2006

Why target moderate redshift clusters for HI gas?

Why target moderate redshift clusters? • at moderate redshifts the whole of the galaxy cluster core and its outskirts are within the field of view of a radio telescope (nearby this not the case – one has to target individual galaxies in clusters one by one) • around a cluster there are many more galaxies that lie within a single telescope pointing than for a typical field pointing • the Butcher-Oemler effect

Why target moderate redshift clusters? • at moderate redshifts the whole of the galaxy cluster core and its outskirts are within the field of view of a radio telescope (nearby this not the case – one has to target individual galaxies in clusters one by one) • around a cluster there are many more galaxies that lie within a single telescope pointing than for a typical field pointing • the Butcher-Oemler effect

Why target moderate redshift clusters? • at moderate redshifts the whole of the galaxy cluster core and its outskirts are within the field of view of a radio telescope (nearby this not the case – one has to target individual galaxies in clusters one by one) • around a cluster there are many more galaxies that lie within a single telescope pointing than for a typical field pointing • the (Harvey) Butcher-Oemler effect

Blue Fraction, f. B The Butcher-Oemler Effect Redshift, z

Blue Fraction, f. B The Butcher-Oemler Effect Abell 370 Redshift, z

Abell 370 a galaxy cluster at z = 0. 37

Abell 370, a galaxy cluster at z = 0. 37 large galaxy cluster of order same size as Coma similar cluster velocity dispersion and X-ray gas temperature optical imaging ANU 40 inch telescope spectroscopic follow-up with the AAT Abell 370 cluster core, ESO VLT image GMRT ~34 hours on cluster HI z = 0. 35 to 0. 39 look-back time ~4 billion years

Abell 370 galaxy cluster 324 galaxies 105 blue (B -V 0. 57) 219 red (BV > 0. 57)

Abell 370 galaxy cluster 3σ extent of X-ray gas R 200 radius at which cluster 200 times denser than the general field

Coadded HI Mass Measurements

HI mass 324 galaxies 219 galaxies 105 galaxies Inner Regions Outer Regions 94 galaxies 156 galaxies The galaxies around Abell 370 are 168 a galaxies mixture of early and late types in a variety of environments. 110 galaxies 214 galaxies

HI mass 324 galaxies 219 galaxies 105 galaxies 94 galaxies 156 galaxies 168 galaxies 110 galaxies 214 galaxies

HI mass 324 galaxies 219 galaxies 105 galaxies 94 galaxies 156 galaxies HI deficient 11 blue galaxies within X-ray gas 168 galaxies 110 galaxies 214 galaxies

HI mass 324 galaxies 219 galaxies 105 galaxies 94 galaxies 156 galaxies 168 galaxies 110 galaxies 214 galaxies

HI mass 324 galaxies 219 galaxies 105 galaxies 94 galaxies 156 galaxies 168 galaxies 110 galaxies 214 galaxies

HI Density Comparisons

HI density Whole Redshift Region z = 0. 35 to 0. 39 Outer Cluster Region Inner Cluster Region

Distribution of galaxies around Abell 370 cluster redshift

HI density Whole Redshift Region z = 0. 35 to 0. 39 Outer Cluster Region Inner Cluster Region

Distribution of galaxies around Abell 370 cluster redshift within R 200 region

HI density Whole Redshift Region z = 0. 35 to 0. 39 Outer Cluster Region Inner Cluster Region

Galaxy HI mass vs Star Formation Rate

Galaxy HI Mass vs Star Formation Rate HIPASS & IRAS data z~0 Doyle & Drinkwater 2006

HI Mass vs Star Formation Rate in Abell 370 all 168 [OII] emission galaxies Average line from Doyle & Drinkwater 2006

HI Mass vs Star Formation Rate in Abell 370 81 blue [OII] emission galaxies Average 87 red [OII] emission galaxies line from Doyle & Drinkwater 2006

Future Observations HI coadding with SKA Pathfinders

SKA – Square Kilometer Array • SKA promises both high sensitivity with a wide field of view • possible SKA sites – South Africa and Australia • both South Africa and Australia are currently building SKA pathfinder telescopes to strengthen their case for site selection • the SKA pathfinder telescopes will also do interesting science

SKA – Square Kilometer Array • SKA promises both high sensitivity with a wide field of view • possible SKA sites – South Africa and Australia (RFI quiet areas) • both South Africa and Australia are currently building SKA pathfinder telescopes to strengthen their case for site selection • the SKA pathfinder telescopes will also do interesting science

SKA – Square Kilometer Array • SKA promises both high sensitivity with a wide field of view • possible SKA sites – South Africa and Australia (RFI quiet areas) • both South Africa and Australia are currently building SKA pathfinder telescopes to strengthen their case for site selection • the SKA pathfinder telescopes will also do interesting science

The SKA pathfinders

ASKAP

Meer. KAT South African SKA pathfinder

ASKAP and Meer. KAT ASKAP parameters Meer. KAT 30 (36) 80 12 m 0. 8 50 K 30 K 700 – 1800 MHz 500 – 2500 MHz 300 MHz 512 MHz Field of View: at 1420 MHz (z = 0) at 700 MHz (z = 1) 30 deg 2 1. 2 deg 2 4. 8 deg 2 Maximum Baseline Length 2 (6) km 10 km Number of Dishes Dish Diameter Aperture Efficiency System Temp. Frequency range Instantaneous bandwidth

ASKAP and Meer. KAT ASKAP parameters Meer. KAT 30 (36) 80 12 m 0. 8 35 K 30 K 700 – 1800 MHz 500 – 2500 MHz 300 MHz 512 MHz Field of View: at 1420 MHz (z = 0) at 700 MHz (z = 1) 30 deg 2 1. 2 deg 2 4. 8 deg 2 Maximum Baseline Length 2 (8) km 10 km Number of Dishes Dish Diameter Aperture Efficiency System Temp. Frequency range Instantaneous bandwidth

ASKAP and Meer. KAT ASKAP parameters Meer. KAT Number of Dishes Dish Diameter Aperture Efficiency System Temp. Frequency range Instantaneous bandwidth Field of View: at 1420 MHz (z = 0) at 700 MHz (z = 1) Maximum Baseline Length 30 (36) 80 12 m 0. 8 35 K 30 K 700 – 1800 MHz 500 – 2500 MHz 300 MHz 512 MHz z = 0. 4 to 1. 0 in a single 30 observation deg 2 z = 0. 2 to 1. 0 in a single 1. 2 observation deg 2 30 deg 2 4. 8 deg 2 2 (8) km 10 km

Simulated ASKAP HI detections (Johnston et al. 2007) z = 0. 45 to 1. 0 one year observations (8760 hours) single telescope pointing, assumes no evolution in the HI mass function Light grey 30 dishes Tsys = 50 K Dark grey 45 dishes Tsys = 35 K Meer. KAT ~4 times more sensitive but smaller field of view

Coadding HI with the SKA Pathfinders Optical Redshift Surveys

Wiggle. Z and z. COSMOS Wiggle. Z z. COSMOS Instrument/Telescope AAOmega on the AAT VIMOS on the VLT Target Selection ultraviolet using the GALEX satellite optical I band IAB < 22. 5 Survey Area 1000 deg 2 total 7 fields minimum size of ~100 deg 2 COSMOS field single field ~2 deg 2 Primary Redshift Range 0. 5 < z < 1. 0 0. 1 < z < 1. 2 Survey Timeline 2006 to 2010 2005 to 2008 nz by survey end 200, 000 20, 000

Wiggle. Z and z. COSMOS Wiggle. Z z. COSMOS Instrument/Telescope AAOmega on the AAT VIMOS on the VLT Target Selection ultraviolet using the GALEX satellite optical I band IAB < 22. 5 Survey Area 1000 deg 2 total 7 fields minimum size of ~100 deg 2 COSMOS field single field ~2 deg 2 Primary Redshift Range 0. 5 < z < 1. 0 0. 1 < z < 1. 2 Survey Timeline 2006 to 2010 2005 to 2008 nz by survey end 200, 000 20, 000

Wiggle. Z and z. COSMOS Wiggle. Z z. COSMOS Instrument/Telescope AAOmega on the AAT VIMOS on the VLT Target Selection ultraviolet using the GALEX satellite optical I band IAB < 22. 5 Survey Area 1000 deg 2 total 7 fields minimum size of ~100 deg 2 COSMOS field single field ~2 deg 2 Primary Redshift Range 0. 5 < z < 1. 0 0. 1 < z < 1. 2 Survey Timeline 2006 to 2010 2005 to 2008 nz by survey end 200, 000 20, 000

Wiggle. Z and ASKAP

Wiggle. Z field square ~10 degrees across data as of May 2009 z= 0. 45 to 1. 0 ASKAP Field of View Area 30 deg 2

ASKAP & Wiggle. Z 100 hrs nz = 7009

ASKAP & Wiggle. Z 100 hrs nz = 7009

ASKAP & Wiggle. Z 100 hrs nz = 7009

ASKAP & Wiggle. Z 1000 hrs Can break up observations among multiple Wiggle. Z fields nz = 7009

z. COSMOS and Meer. KAT

z. COSMOS field Meer. KAT beam size at 1420 MHz z = 0 Meer. KAT beam size at 1000 MHz z = 0. 4 square ~1. 3 degrees across data as of March 2008 z = 0. 2 to 1. 0 7118 galaxies

Meer. KAT & z. COSMOS 100 hrs ~65 per cent of z. COSMOS galaies are star-forming, blue, diskdominate galaxies (Mignoli et al. 2008) nz = 4627

Meer. KAT & z. COSMOS 100 hrs nz = 4627

Meer. KAT & z. COSMOS 100 hrs nz = 4627

Meer. KAT & z. COSMOS 1000 hrs nz = 4627

HI Science with SKA Pathfinders at High Redshift

Why is there a dramatic evolution in the Cosmic Star Formation Rate Density and only minimal evolution in the Cosmic HI Gas Density?

SFRD & HI density Evolution Star Formation Rate Density Evolution HI Density Evolution

Evolution of HI Gas in Galaxies log(SFR) log(MHI) SFR = a (MHI)m HI = MHI SFRD = SFR Vol SFRD = a × (MHI)m Vol m ~ 1. 7 at z = 0 (Doyle & Drinkwater 2006)

Evolution of HI Gas in Galaxies log(SFR) log(MHI) SFR = a (MHI)m HI = MHI SFRD = SFR Vol SFRD = a × (MHI)m Vol m ~ 1. 7 at z = 0 (Doyle & Drinkwater 2006)

Evolution of HI Gas in Galaxies log(SFR) log(MHI) SFR = a (MHI)m HI = MHI SFRD = SFR Vol SFRD = a × (MHI)m Vol m ~ 1. 7 at z = 0 (Doyle & Drinkwater 2006)

Evolution of HI Gas in Galaxies log(SFR) log(MHI) SFR = a (MHI)m HI = MHI SFRD = SFR Vol SFRD = a × (MHI)m Vol m ~ 1. 7 at z = 0 (Doyle & Drinkwater 2006)

Evolution of HI Gas in Galaxies log(SFR) log(MHI) SFR = a (MHI)m HI = MHI SFRD = SFR Vol SFRD = a × (MHI)m Vol m ~ 1. 7 at z = 0 (Doyle & Drinkwater 2006)

Testing Ideas on HI Gas Evolution

Generated HI Mass Functions z= 0 H Im ass func tion Integrated HI density = current value (~5× 107 M Mpc-3) Integrated SFRD = maximum value observed (~0. 3 M yr-1 Mpc-3)

Generated HI Mass Functions z= 0 H Im ass func tion Integrated HI density = twice current value (~108 M Mpc-3) Integrated SFRD = maximum value observed (~0. 3 M yr-1 Mpc-3)

Varying Galaxy SFR-HI Gas Relationship SFR = a (MHI)m current values Integrated HI density = current value (~5× 107 M Mpc-3) Integrated SFRD = maximum value observed (~0. 3 M yr-1 Mpc-3)

Observational Evidence

Downsizing • the bulk of the stellar populations of the most massive galaxies formed at early times (Heavens et al. 2004, Thomas et al. 2005 & others) • the sites of active star formation shift from the high-mass galaxies at earliest times to the lower-mass galaxies at later periods (Cowie et al. 1996, Gunzman et al. 1997 & others) • high mass galaxies with active star formation highest HI gas content? • SKA pathfinders observations test hypotheses

Downsizing • the bulk of the stellar populations of the most massive galaxies formed at early times (Heavens et al. 2004, Thomas et al. 2005 & others) • the sites of active star formation shift from the high-mass galaxies at earliest times to the lower-mass galaxies at later periods (Cowie et al. 1996, Gunzman et al. 1997 & others) • high mass galaxies with active star formation highest HI gas content? • SKA pathfinders observations test hypotheses

Downsizing • the bulk of the stellar populations of the most massive galaxies formed at early times (Heavens et al. 2004, Thomas et al. 2005 & others) • the sites of active star formation shift from the high-mass galaxies at earliest times to the lower-mass galaxies at later periods (Cowie et al. 1996, Gunzman et al. 1997 & others) • high mass galaxies with active star formation highest HI gas content? • SKA pathfinders observations test hypotheses

Downsizing • the bulk of the stellar populations of the most massive galaxies formed at early times (Heavens et al. 2004, Thomas et al. 2005 & others) • the sites of active star formation shift from the high-mass galaxies at earliest times to the lower-mass galaxies at later periods (Cowie et al. 1996, Gunzman et al. 1997 & others) • high mass galaxies with active star formation highest HI gas content? • use SKA pathfinders observations to test hypotheses

Bonus Material

Two Unusual Radio Continuum Objects in the Field of Abell 370

1. The DP Structure

Single RC Single Radio Contiuum Source

Double RC Double Radio Contiuum Source

The DP Structure GMRT image resolution ~3. 3 arcsec at 1040 MHz Peak flux = 1. 29 m. Jy/Beam Total flux density ~ 23. 3 m. Jy 60 arcsec across

The DP Structure V band optical image from ANU 40 inch WFI 60 arcsec across

The DP Structure Radio contours at 150, 300, 450, 600, 750, 900 & 1150 Jy/beam RMS ~ 20 Jy

The DP Structure Optical as Contours

The DP Structure Galaxies all at similar redshifts z ~ 0. 3264

The DP Group

The DP Group Abell 370 ~167 Mpc difference between cluster Abell 370 and DP group in commoving distance NOT related objects DP Group group well outside GMRT HI redshift range

DP Structure Galaxy 4 – source of DP Structure The DP Group

The DP Group 10 arcmin square box ~2800 kpc at z = 0. 326 galaxy group/small cluster

Explaining the Structure

DP 1 a galaxy

DP 2 pair of radio jets

DP 3

DP 4

DP 5 galaxy moving through intercluster medium

DP 6

DP 7

DP 8 currently I have the radio jets orientated along page with respect to the observer

DP 9 changing orientation of the radio jets with respect to the observer

DP 10

DP 11

2. A Radio Gravitational Arc?

Radio Arc V band optical image from ANU 40 inch Abell 370 cluster 8 arcmin square

Radio Arc V band optical image from ANU 40 inch Abell 370 cluster 8 arcmin square

Radio Arc V band optical image from ANU 40 inch image centred on one of the two c. D galaxies near the centre of the Abell 370 cluster 50 arcsec square

Radio Arc optical image from Hubble Space Telescope optical arc in Abell 370 was the first detected gravitational lensing event by a galaxy cluster (Soucail et al. 1987)

Radio Arc GMRT image resolution ~3. 3 arcsec at 1040 MHz Peak flux = 490 Jy/Beam c. D galaxy Peak flux = 148 Jy/Beam Noise ~20 Jy noise

Radio Arc Radio contours at 80, 100, 120, 140, 180, 220, 260, 320, 380 & 460 Jy/beam RMS ~ 20 Jy

Radio Arc Optical as Contours

Conclusion

Conclusion • one can use coadding with optical redshifts to make measurement of the HI 21 -cm emission from galaxies at redshifts z > 0. 1 • using this method the cosmic neutral gas density at z = 0. 24 (look-back time of ~3 billion years) has been measured and the value is consistent with that from damped Lyα measurements • galaxy cluster Abell 370 at z = 0. 37 (look-back time of ~4 billion years) has significantly more gas than similar clusters at z ~ 0 • the SKA pathfinders ASKAP and Meer. KAT can measure the HI 21 -cm emission from galaxies out to z = 1. 0 (look-back time of ~8 billion years) using the coadding technique with existing optical redshift surveys