The Cosmic Evolution of Neutral Atomic Hydrogen Gas Philip Lah

The Cosmic Evolution of Neutral Atomic Hydrogen Gas Philip Lah University of Sydney Colloquium 27 November 2014

Collaborators: Frank Briggs (ANU) Jayaram Chengalur (NCRA) Matthew Colless (ANU) Roberto De Propris (FINCA) Michael Pracy (USyd) Jonghwan Rhee (UWA)

Neutral Atomic Hydrogen Gas in Galaxies

Galaxy M33: optical

Galaxy M33: HI 21-cm emission

Galaxy M33: optical and HI

Galaxy M33: optical

Why Study Neutral Atomic Hydrogen Gas?

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

The Cosmic Evolution of Star Formation

The History of Star Formation in the Universe

Why Study Neutral Atomic Hydrogen Gas? Because you can measure it!

The Cosmic Evolution of HI Gas

Reionisation

HI density nothing

How to measure? 1. 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 photon

Neutral atomic hydrogen creates 21 cm radiation

Neutral atomic hydrogen creates 21 cm radiation HI 21 cm emission decay half life ~10 million years

HI Mass Assuming an optically thin neutral hydrogen cloud M M HI 236 1 z S mjy d L Mpc 2 V kms 1 M HI* = 6.2 10 9 M (Zwaan et al. 2003)

HI 21-cm Emission: The Observations

HI density HIPASS Zwaan05

HI density HIPASS Zwaan05 blind HI 21 cm emission direct detection Zwaan 2005 HIPASS 4315 galaxies

HI density ALFALFA Martin10

HI density ALFALFA Martin10 blind HI 21 cm emission direct detection Martin 2010 ALFALFA 10,119 galaxies

How to measure? 2. Damped Lyman-α Absorption Systems

Intensity Lyman-α Absorption Systems hydrogen gas clouds observer quasar Lyman-α absorption by clouds Lyman-α emission Wavelength

Intensity Damped Lyman-α QSO 1425+6039 redshift z = 3.2 Keck HIRES optical spectrum Lyα emission Lyman-α forest DLA 4200 4400 4600 4800 5000 5200 Wavelength (Å) Lyman-α 1216 Å rest frame

Damped Lyman-α: The Observations

HI density Noterdaeme09

HI density Noterdaeme09 Damped Lyman-α Noterdaeme 2009 SDSS 937 absorbers

HI density Noterdaeme12

HI density Noterdaeme12 Damped Lyman-α Noterdaeme 2012 BOSS 6839 absorbers

HI density Zafar13

HI density Zafar13 Damped Lyman-α Zafar 2013 UVES 122 quasars

Lower Redshift Damped Lyman-α

HI density Rao06

HI density Rao06 Damped Lyman-α Rao 2006 MgII FeII systems UV HST 197 systems

Coadding HI 21 cm Emission Signals

Coadding HI signals Radio Data Cube DEC RA

Coadding HI signals Radio Data Cube DEC positions of optical galaxies RA

flux Coadding HI signals frequency

flux z1 Coadding HI signals z2 z3 z1, z2 & z3 optical redshifts of galaxies frequency

flux Coadding HI signals z1 z2 Coadded HI signal z3 velocity velocity

flux Coadding HI signals z1 z2 Coadded HI signal z3 velocity velocity Noise m N N = number of galaxies

Coadding HI 21 cm Emission: The Observations

HI density Lah07

HI density Lah07 HI 21 cm emission stacking Lah 2007 GMRT/Subaru/AAT 154 galaxies

HI density Freudling11

HI density Freudling11 HI 21 cm emission targeted Freudling 2011 AUDS Arecibo 18 galaxies

HI density Rhee13

HI density Rhee13 HI 21 cm emission stacking Rhee 2013 WSRT CNOC 59 + 69 galaxies

HI density Delhaize13

HI density Delhaize13 HI 21 cm emission stacking Delhaize 2013 Parkes 2dFGRS 3277 galaxies HIPASS 2dFGRS 15093 galaxies

HI density VVDS14

HI density VVDS14 HI 21 cm emission stacking Rhee thesis VVDS14 GMRT/AAT/MMT 165 galaxies

HI density zcosmos14

HI density zcosmos14 HI 21 cm emission stacking Rhee thesis GMRT/zCOSMOS

HI density Hoppmann14

HI density Hoppmann14 HI 21 cm emission targeted Hoppmann 2014 AUDS Arecibo 105 galaxies

HI density Current Status Current Status

HI density Low z average 4σ

HI density High z average 7σ

Neutral Atomic Hydrogen Gas In Different Environments

Nearby Galaxy Clusters Are Deficient In HI Gas

HI Deficiency in Clusters Def HI = log(m HI exp. / M HI obs) Gavazzi et al. 2006 Def HI = 1 is 10% of expected HI gas expected gas estimate based on optical diameter and Hubble type

Cluster Stacking Observations

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 Abell 370 cluster core, ESO VLT image

Distribution of galaxies around Abell 370 cluster redshifts AAT complete GMRT redshift range

Distribution of galaxies around Abell 370 8 Mpc radius region: 220 galaxies cluster redshift

HI density Outer Cluster Region Inner Cluster Region

Distribution of galaxies around Abell 370 cluster redshift

Distribution of galaxies around Abell 370 110 galaxies cluster redshift within R 200 region

HI density Outer Cluster Region Inner Cluster Region

The Next Generation of Observations

Radio Telescopes SKA1 SYSTEM BASELINE DESIGN 2013-03-12

Giant Metrewave Radio Telescope 45 m diameter dishes 30 dishes low frequency

HI density GMRT 1000 MHz ~610 MHz

Karl G. Jansky Very Large Array 25 m diameter dishes 27 dishes high frequency

HI density JVLA 1000 MHz

JVLA HI Survey CHILES (the COSMOS HI Large Extragalactic Survey) z = 0 to 0.45, 1000 hours in B array

ASKAP 12 m diameter dishes 36 dishes focal plane array

HI density ASKAP 700 MHz

ASKAP HI Surveys WALLABY (Widefield ASKAP L-Band Legacy All-Sky Blind Survey) - z = 0 to 0.26-75% of the entire sky- 9600 hrs DINGO (Deep Investigations of Neutral Gas Origins) - z = 0 to 0.4 - GAMA regions - 7500 hrs, ~290 deg 2 FLASH (The First Large Absorption Survey in HI) - a blind HI absorption-line survey, out to z = 1.0, 3000 deg 2, 2400 hrs, HI stacking using WiggleZ redshifts

ASKAP HI Surveys WALLABY (Widefield ASKAP L-Band Legacy All-Sky Blind Survey) - z = 0 to 0.26-75% of the entire sky- 9600 hrs DINGO (Deep Investigations of Neutral Gas Origins) - z = 0 to 0.4 - GAMA regions - 7500 hrs, ~290 deg 2 FLASH (The First Large Absorption Survey in HI) - a blind HI absorption-line survey, 0.5 < z <1.0, 25000 deg 2, 3200 hrs, deeper pointings HI stacking using WiggleZ redshifts

MeerKAT South African SKA pathfinder 13.5 m diameter dishes 64 dishes

HI density MeerKAT 580 MHz

MeerKAT HI Surveys LADUMA (Looking At the Distant Universe with the MeerKAT Array) z > 1.0, ~5000 hours, single pointing Extended Chandra Deep Field South (ECDF-S)

The SKA-mid

The SKA-mid 64 13.5-m diameter dishes from the MeerKAT array and 190 15-m dishes ~15% of full SKA

HI density SKA-mid 350 MHz

Then On To The SKA

Additional Slides

A Radio Gravitational Arc?

Radio Arc V band optical image from ANU 40 inch Abell 370 cluster 8 arcmin 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 50 arcsec on a side radio contour levels start at 28.5 μjy/ beam (3σ) VLA L-band radio data has a synthesised beam size of 1.5 arcsec.

VLA C-band 4860 MHz 30 arcsec on a side Peak 160 µjy/beam

VLA L-band 1400 MHz 30 arcsec on a side Peak 350 µjy/beam

GMRT 1040 MHz 30 arcsec on a side Peak 490 µjy/beam

Theoretical Model of Arc - based on Parametric Mass Model of Abell 370 by Richard et al. (2010) - images are 30.3 arcsec across, contour spacing geometric progression, with a factor 1.5 in between each contour

Radio Arc 50 arcsec on a side radio contour levels start at 28.5 μjy/ beam (3σ) VLA L-band radio data has a synthesised beam size of 1.5 arcsec.

HI 21cm emission HI 21 cm emission decay half life ~10 million years 1 M 1.2 10 57 atoms of hydrogen atoms total HI gas in galaxies ~ 10 7 to 10 10 M HI 21 cm luminosity of ~2 10 32 to 2 10 35 ergs s -1 in star forming galaxies luminosity of H emission ~3 10 39 to 3 10 42 ergs s -1

HI density Molonglo?? Molonglo Bandwidth 3 MHz Centre frequency 843 MHz z = 0.681 to 0.687

Radio Arc Theory Arc model based on Parametric Mass Model of Abell 370 published by Richard et al. (2010). images are 30.3 arcsec across, contour spacing geometric progression, with a factor 1.5 in between each contour

Giant Metrewave Radio Telescope