1. Neutral Hydrogen Gas in Abell 370, a Galaxy Cluster at z = 0.37 NCRA 17 th July 2008 Philip Lah

2. Collaborators: Jayaram Chengalur (NCRA) Michael Pracy (ANU) Frank Briggs (ANU) Matthew Colless (AAO) Roberto De Propris (CTIO)

3. Giant Metrewave Radio Telescope

7. Talk Outline Introduction evolution in clusters & star formation rate density vs redshift HI 21-cm emission & the HI coadding technique review of current HI measurements at z > 0.1 Abell 370, a Galaxy Cluster at z = 0.37 HI in Abell 370 star formation in Abell 370 two unusual radio continuum objects around Abell 370 Future Observations with SKA pathfinders using ASKAP and WiggleZ using MeerKAT and zCOSMOS

8. Evolution in Galaxy Clusters

9. Galaxy Cluster: Coma

10. Butcher-Oemler Effect Butcher-Oemler Effect increasing fraction of blue galaxies in clusters with redshift nearby clusters neutral hydrogen gas deficient

11. The Cosmic Star Formation Rate Density

12. SFRD vs z Hopkins 2004

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

14. Neutral Atomic Hydrogen (HI) 21-cm Emission

15. Neutral atomic hydrogen creates 21 cm radiation proton electron

16. Neutral atomic hydrogen creates 21 cm radiation

19. photon

20. Neutral atomic hydrogen creates 21 cm radiation

21. HI 21cm Emission at High Redshift

22. HI 21cm emission at z > 0.1 single galaxy at z = 0.176  WSRT 200 hours (Zwaan et al. 2001, Science, 293, 1800) single galaxy at z = 0.1887  VLA ~80 hours (Verheijen et al. 2004,in IAU Symposium Vol 195, p. 394) two galaxy clusters at z = 0.188 and z = 0.206  WSRT 420 hours  42 galaxies detected  HI gas masses 5  10 9 to 4  10 10 M  (Verheijen et al. 2007, ApJL, 668, L9) galaxies with redshifts z = 0.17 to 0.25 observed with Arecibo  detected 26 from 33 observed  HI gas masses (2 to 6)  10 10 M  (Catinella et al. 2007, in IAU Symposium Vol 235, p. 39)

23. HI 21cm emission at z > 0.1 single galaxy at z = 0.176  WSRT 200 hours (Zwaan et al. 2001, Science, 293, 1800) single galaxy at z = 0.1887  VLA ~80 hours (Verheijen et al. 2004,in IAU Symposium Vol 195, p. 394) two galaxy clusters at z = 0.188 and z = 0.206  WSRT 420 hours  42 galaxies detected  HI gas masses 5  10 9 to 4  10 10 M  (Verheijen et al. 2007, ApJL, 668, L9) galaxies with redshifts z = 0.17 to 0.25 observed with Arecibo  detected 26 from 33 observed  HI gas masses (2 to 6)  10 10 M  (Catinella et al. 2007, in IAU Symposium Vol 235, p. 39)

24. HI 21cm emission at z > 0.1 single galaxy at z = 0.176  WSRT 200 hours (Zwaan et al. 2001, Science, 293, 1800) single galaxy at z = 0.1887  VLA ~80 hours (Verheijen et al. 2004,in IAU Symposium Vol 195, p. 394) two galaxy clusters at z = 0.188 and z = 0.206  WSRT 420 hours  42 galaxies detected  HI gas masses 5  10 9 to 4  10 10 M  (Verheijen et al. 2007, ApJL, 668, L9) galaxies with redshifts z = 0.17 to 0.25 observed with Arecibo  detected 26 from 33 observed  HI gas masses (2 to 6)  10 10 M  (Catinella et al. 2007, in IAU Symposium Vol 235, p. 39)

25. HI 21cm emission at z > 0.1 single galaxy at z = 0.176  WSRT 200 hours (Zwaan et al. 2001, Science, 293, 1800) single galaxy at z = 0.1887  VLA ~80 hours (Verheijen et al. 2004,in IAU Symposium Vol 195, p. 394) two galaxy clusters at z = 0.188 and z = 0.206  WSRT 420 hours  42 galaxies detected  HI gas masses 5  10 9 to 4  10 10 M  (Verheijen et al. 2007, ApJL, 668, L9) galaxies with redshifts z = 0.17 to 0.25 observed with Arecibo  detected 26 from 33 observed  HI gas masses (2 to 6)  10 10 M  (Catinella et al. 2007, in IAU Symposium Vol 235, p. 39)

26. HI 21cm emission at z > 0.1 our group using the GMRT measured the coadded HI signal from 121 star forming galaxies at z = 0.24 (look-back time ~3.8 Gyr)  GMRT ~48 hours on field  weighted average M HI = (2.26 ± 0.90) ×10 9 M  (Lah et al. 2007, MNRAS, 376, 1357)

27. Abell 370 a Galaxy Cluster at z = 0.37

28. Abell 370, a galaxy cluster at z = 0.37 large galaxy cluster of order same size as Coma optical imaging ANU 40 inch telescope spectroscopic follow- up with the AAT GMRT ~34 hours on cluster

29. Abell 370 – R band images Thumbnails 10’’ sq 324 galaxies with useful redshifts (z~0.37) ordered by observed R band magnitudes

30. Abell 370 galaxy cluster 324 galaxies 105 blue (B-V  0.57) 219 red (B-V > 0.57) Abell 370 galaxy cluster

31. 3σ extent of X-ray gas R 200  radius at which cluster 200 times denser than the general field

32. redshift histogram 324 useful redshifts

33. redshift histogram 324 useful redshifts GMRT sideband frequency limits

34. Galaxy Sizes I want galaxies to be unresolved. For the galaxies at z = 0.24 I used an estimate of the HI size from the optical properties of spiral and irregular field galaxies and the smoothed radio data. Major Complication!! The Abell 370 galaxies are a mixture of early and late types in a variety of environments.

35. Galaxy Sizes I want galaxies to be unresolved. For the galaxies at z = 0.24 I used an estimate of the HI size from the optical properties of spiral and irregular field galaxies and the smoothed radio data. Major Complication!! The Abell 370 galaxies are a mixture of early and late types in a variety of environments.

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

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

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

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

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

41. HI all spectrum all Abell 370 galaxies neutral hydrogen gas measurement using 324 redshifts – large smoothing M HI = (6.6 ± 3.5) ×10 9 M 

42. HI Flux – All Galaxies

43. HI blue outside x-ray gas blue galaxies outside of x-ray gas measurement of neutral hydrogen gas content using 94 redshifts – large smoothing M HI = (23.0 ± 7.7) ×10 9 M 

44. HI Flux – Blue Galaxies Outside X-ray Gas

45. Comparisons with the Literature

46. Average HI Mass Comparisons with Coma

47. Abell 370 and Coma Comparison 214 galaxies 324 galaxies 110 galaxies

48. Abell 370 and Coma Comparison 214 galaxies 324 galaxies 110 galaxies

49. Abell 370 and Coma Comparison 214 galaxies 324 galaxies 110 galaxies

50. HI Density Comparisons

51. HI density field

55. HI density - inner regions of clusters within 2.5 Mpc of cluster centers

56. HI Mass to Light Ratios

57. HI mass to optical B band luminosity for Abell 370 galaxies Uppsala General Catalog Local Super Cluster (Roberts & Haynes 1994)

58. HI Mass to Light Ratios HI mass to optical B band luminosity for Abell 370 galaxies Uppsala General Catalog Local Super Cluster (Roberts & Haynes 1994)

59. Galaxy HI mass vs Star Formation Rate

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

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

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

63. Star Formation Rate from [OII] and radio continuum emission

64. radio continuum emission produced from relativistic electrons moving in magnetic field of the galaxy - synchrotron radiation relativistic electrons produced by supernova remnants, what remains after the death of massive, short-lived stars in theory - number of supernova remnants related to star formation rate in galaxy in practice - empirical relationship - agrees with other star formation rate indicators Radio Continuum – Star Formation Connection

65. Radio Continuum vs. [OII] Star Formation Rate all 168 [OII] emission galaxies line from Bell 2003 Average

66. Radio Continuum vs. [OII] Star Formation Rate line from Bell 2003 81 blue [OII] emission galaxies 87 red [OII] emission galaxies Average

67. Two Unusual Radio Continuum Objects in the field of Abell 370

68. 1.The De Propris Structure

69. Example Radio Continuum Jet

70. The De Propris Structure FIRST image 60 arcsec across VLA at 1.4 GHz Resolution ~5 arcsec

71. The De Propris Structure GMRT image resolution ~3.3 arcsec at 1040 MHz Peak flux = 1.29 mJy/Beam Total flux density ~ 23.3 mJy

72. The De Propris Structure V band optical image from ANU 40 inch WFI

73. The De Propris Structure Radio contours at 150, 300, 450, 600, 750, 900 & 1150  Jy/beam RMS ~ 20  Jy

74. The De Propris Structure Optical as Contours

75. The De Propris Structure Galaxies all at similar redshifts z ~ 0.3264

76. The De Propris Group

77. ~167 Mpc difference between cluster Abell 370 and De Propris group in comoving distance NOT related objects group well outside GMRT HI redshift range The De Propris Group Abell 370 De Propris Group

78. De Propris Structure Galaxy 4 – source of De Propris Structure The De Propris Group

79. 10 arcmin square box ~2800 kpc at z = 0.326 galaxy group/small cluster galaxies moving through intra-group medium of hot ionised gas ionised gas pushes radio jet bending it back on itself to create the strange shape

80. 2. A Radio Gravitational Arc?

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

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

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

84. 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)

85. Radio Arc GMRT image resolution ~3.3 arcsec at 1040 MHz Peak flux = 490  Jy/Beam cD galaxy Peak flux = 148  Jy/Beam Noise ~20  Jy noise

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

87. Radio Arc Optical as Contours

88. Future Observations - HI coadding with SKA Pathfinders

89. SKA – Square Kilometer Array final site decision by 2012?? – money will be the deciding factor both South Africa and Australia are building SKA pathfinder telescopes to strengthen their case for site selection – also do science SKA promises both high sensitivity with wide field of view possible SKA sites – South Africa and Australia

90. Why South Africa and Australia?

91. Population Density – India

92. Population Density – South Africa

93. Population Density – Australia

94. Radio Interference 10 8 10 9 Frequency (Hz)

95. The SKA Pathfinders

96. ASKAP

97. MeerKAT South African SKA pathfinder

98. ASKAP and MeerKAT parameters ASKAPMeerKAT Number of Dishes 4580 Dish Diameter 12 m Aperture Efficiency 0.8 System Temp. 35 K30 K Frequency range 700 – 1800 MHz700 – 2500 MHz Instantaneous bandwidth 300 MHz512 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 8 km10 km

99. ASKAP and MeerKAT parameters ASKAPMeerKAT Number of Dishes 4580 Dish Diameter 12 m Aperture Efficiency 0.8 System Temp. 35 K30 K Frequency range 700 – 1800 MHz700 – 2500 MHz Instantaneous bandwidth 300 MHz512 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 8 km10 km

100. ASKAP and MeerKAT parameters ASKAPMeerKAT Number of Dishes 4580 Dish Diameter 12 m Aperture Efficiency 0.8 System Temp. 35 K30 K Frequency range 700 – 1800 MHz700 – 2500MHz Instantaneous bandwidth 300 MHz512 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 8 km10 km z = 0.45 to 1.0 in a single observation z = 0.2 to 1.0 in a single observation

101. single pointing assumes no evolution in the HI mass function (Johnston et al. 2007) MeerKAT - will detect galaxies easier - more sensitive - but in a single pointing will end up with fewer total detections due to smaller field of view z = 0.45 to 1.0 980 MHz to 700 MHz one year observations (8760 hours) Simulated ASKAP HI detections

102. What I could do with the SKA pathfinders using optical coadding of HI if you gave them to me TODAY.

103. WiggleZ and zCOSMOS WiggleZzCOSMOS Instrument/TelescopeAAOmega on the AATVIMOS on the VLT Target Selection ultraviolet using the GALEX satellite optical I band I AB < 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 < 1.00.1 < z < 1.2 Survey Timeline2006 to 20102005 to 2008 n z by survey end176,00020,000 n z in March 2008~62,000~10,000

104. WiggleZ and zCOSMOS WiggleZzCOSMOS Instrument/TelescopeAAOmega on the AATVIMOS on the VLT Target Selection ultraviolet using the GALEX satellite optical I band I AB < 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 < 1.00.1 < z < 1.2 Survey Timeline2006 to 20102005 to 2008 n z by survey end176,00020,000 n z in March 2008~62,000~10,000

105. WiggleZ and zCOSMOS WiggleZzCOSMOS Instrument/TelescopeAAOmega on the AATVIMOS on the VLT Target Selection ultraviolet using the GALEX satellite optical I band I AB < 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 < 1.00.1 < z < 1.2 Survey Timeline2006 to 20102005 to 2008 n z by survey end176,00020,000 n z in March 2008~62,000~10,000

106. WiggleZ and ASKAP

107. WiggleZ field data as of March 2008 z = 0.45 to 1.0 ASKAP beam size Diameter 6.2 degrees Area 30 deg 2 ~10 degrees across

108. ASKAP & WiggleZ 100hrs n z = 3887

109. ASKAP & WiggleZ 100hrs n z = 3887

110. ASKAP & WiggleZ 100hrs n z = 3887

111. ASKAP & WiggleZ 1000hrs n z = 3887

112. zCOSMOS and MeerKAT

113. zCOSMOS field data as of March 2008 z = 0.2 to 1.0 7118 galaxies MeerKAT beam size at 1420 MHz z = 0 MeerKAT beam size at 1000 MHz z = 0.4 square ~1.3 degrees across

114. MeerKAT & zCOSMOS 100hrs n z = 3559

115. MeerKAT & zCOSMOS 100hrs n z = 3559

116. MeerKAT & zCOSMOS 100hrs n z = 3559

117. MeerKAT & zCOSMOS 1000hrs n z = 3559

118. Conclusion

119. Abell 370 a galaxy cluster at z = 0.37 has significantly more gas than similar clusters at z ~ 0 despite this fact, galaxies in regions of higher density within Abell 370 have less gas than galaxies located in regions of lower density, the same trend seen in nearby clusters there are two unusual radio continuum structures in the field of Abell 370 – a twisted radio jet and a possible radio gravitational arc the SKA pathfinders ASKAP and MeerKAT can measure significant amounts of HI 21 cm emission out to z = 1.0 using the coadding technique with existing redshift surveys Conclusion

121. Additional Slides

122. RFI – 950 MHz mobile phones Field of view small – 45 m dishes bandpass small 32 MHz – upgrade coming but will not soon work for all dishes simultaneously longer baselines resolve HI in galaxies Why not GMRT?