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

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

3. Neutral Atomic Hydrogen Gas in Galaxies

4. Galaxy M33: optical

5. Galaxy M33: HI 21-cm emission

6. Galaxy M33: optical and HI

7. Galaxy M33: optical

8. Why Study Neutral Atomic Hydrogen Gas?

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

10. The Cosmic Evolution of Star Formation

11. The History of Star Formation in the Universe

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

14. The Cosmic Evolution of HI Gas

15. Reionisation

16. HI density – nothing

17. How to measure? 1. HI 21-cm Emission

19. Neutral atomic hydrogen creates 21 cm radiation proton electron

20. Neutral atomic hydrogen creates 21 cm radiation

23. photon

24. Neutral atomic hydrogen creates 21 cm radiation

25. HI 21 cm emission decay half life ~10 million years

26. HI Mass Assuming an optically thin neutral hydrogen cloud M HI * = 6.2 ×10 9 M  (Zwaan et al. 2003)

27. HI 21-cm Emission: The Observations

28. HI density – HIPASS Zwaan05

29. Zwaan 2005 HIPASS 4315 galaxies blind HI 21 cm emission direct detection

30. HI density – ALFALFA Martin10

31. Martin 2010 ALFALFA 10,119 galaxies blind HI 21 cm emission direct detection

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

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

35. Damped Lyman-α Lyman-α 1216 Å rest frame Intensity Wavelength (Å) 4200440046004800 50005200 Lyα emission QSO 1425+6039 redshift z = 3.2 Keck HIRES optical spectrum DLA Lyman-α forest

36. Damped Lyman-α: The Observations

37. HI density – Noterdaeme09

38. Noterdaeme 2009 SDSS 937 absorbers Damped Lyman-α

39. HI density – Noterdaeme12

40. Noterdaeme 2012 BOSS 6839 absorbers Damped Lyman-α

41. HI density – Zafar13

42. Zafar 2013 UVES 122 quasars Damped Lyman-α

43. Lower Redshift Damped Lyman-α

44. HI density – Rao06

45. Rao 2006 MgII–FeII systems UV HST 197 systems Damped Lyman-α

46. Coadding HI 21 cm Emission Signals

47. Coadding HI signals RA DEC Radio Data Cube Frequency HI redshift

48. Coadding HI signals RA DEC Radio Data Cube Frequency HI redshift positions of optical galaxies

49. Coadding HI signals frequency flux

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

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

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

53. Coadding HI 21 cm Emission: The Observations

54. HI density – Lah07

55. Lah 2007 GMRT/Subaru/AAT 154 galaxies HI 21 cm emission stacking

56. HI density – Freudling11

57. Freudling 2011 AUDS Arecibo 18 galaxies HI 21 cm emission targeted

58. HI density – Rhee13

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

60. HI density – Delhaize13

61. Delhaize 2013 Parkes 2dFGRS 3277 galaxies HIPASS 2dFGRS 15093 galaxies HI 21 cm emission stacking

62. HI density – VVDS14

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

64. HI density – zCOSMOS14

65. HI 21 cm emission stacking Rhee thesis GMRT/zCOSMOS

66. HI density – Hoppmann14

67. HI 21 cm emission targeted Hoppmann 2014 AUDS Arecibo 105 galaxies

68. HI density – Current Status Current Status

69. HI density – Low z average 4σ4σ

70. HI density – High z average 7σ7σ

71. Neutral Atomic Hydrogen Gas In Different Environments

72. Nearby Galaxy Clusters Are Deficient In HI Gas

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

74. Cluster Stacking Observations

75. Abell 370, a galaxy cluster at z = 0.37 Abell 370 cluster core, ESO VLT image large galaxy cluster of order same size as Coma  similar cluster velocity dispersion and X-ray gas temperature

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

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

78. Inner Cluster Region Outer Cluster Region HI density

79. Inner Cluster Region Outer Cluster Region HI density

80. cluster redshift Distribution of galaxies around Abell 370

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

82. Inner Cluster Region Outer Cluster Region HI density

83. The Next Generation of Observations

84. Radio Telescopes SKA1 SYSTEM BASELINE DESIGN 2013-03-12

85. Radio Telescopes SKA1 SYSTEM BASELINE DESIGN 2013-03-12

86. Radio Telescopes SKA1 SYSTEM BASELINE DESIGN 2013-03-12

87. Radio Telescopes SKA1 SYSTEM BASELINE DESIGN 2013-03-12

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

89. HI density – GMRT 1000 MHz ~610 MHz

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

91. HI density –JVLA 1000 MHz

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

93. ASKAP 12 m diameter dishes 36 dishes focal plane array

94. HI density – ASKAP 700 MHz

95. 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

96. 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

97. 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

98. MeerKAT South African SKA pathfinder 13.5 m diameter dishes 64 dishes

99. HI density – MeerKAT 580 MHz

100. 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)

101. The SKA-mid

102. 64 × 13.5-m diameter dishes from the MeerKAT array and 190 × 15-m dishes ~15% of full SKA

103. HI density – SKA-mid 350 MHz

104. Then On To The SKA

106. Additional Slides

107. A Radio Gravitational Arc?

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

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

110. 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)

111. 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.

112. VLA C-band 4860 MHz 30 arcsec on a side Peak 160 µJy/Beam

113. VLA L-band 1400 MHz 30 arcsec on a side Peak 350 µJy/Beam

114. GMRT 1040 MHz 30 arcsec on a side Peak 490 µJy/Beam

115. 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

116. 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.

118. 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

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

120. 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

121. Giant Metrewave Radio Telescope