Westerbork ultra-deep HI observations at z=0.2

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1 Westerbork ultra-deep HI observations at z=0.2 Ryan Cybulski Boris Deshev Jacqueline van Gorkom K.S. Dwarakanath Aeree Chung Yara Jaffe Glenn Morrison Bianca Poggianti David Schiminovich Arpad Szomoru Marc Verheijen Eric Wilcots Min Yun TF35 workshop, 1 Apr 2012, Green Bank

2 HI, ICM, SFR, SP interrelations Coma Abell 2670 Poggianti & van Gorkom, 2001 Bravo-Alfaro et al, 2001 Role and fate of HI in galaxy (trans)formation & evolution

3 Butcher-Oemler effect The fraction of blue (starforming?) galaxies in clusters increases with redshift and peaks in cluster outskirts. 0.4 blue fraction A963 Butcher & Oemler, redshift Abraham et al, 1996 Different accretion rate/efficiency or different field population?

4 WSRT Survey Volume & Large Scale Structure 4 3 combined volume: 7x10 Mpc 325 Mpc Alfalfa HIPASS SDSS redshift slice

5 A tale of two clusters work in progress Abell 963 INT - B,R Abell Mpc 1 Mpc z=0.206 z=0.188

6 A tale of two clusters work in progress Abell Mpc INT - B,R Abell Mpc z= Mpc 1 Mpc z=0.188

7 GALEX NUV / FUV imaging Abell 963 Abell x1 Sensitive to the youngest stellar populations 1 x1

8 GALEX NUV / FUV imaging Abell 963 Abell x1 Sensitive to the youngest stellar populations 1 x1

9 Ancillary data GALEX FUV & NUV INT B & R imaging SDSS ugriz photometry (shallow) UKIRT zyjhk (allocated) Spitzer 3.6, 5.0, 24, 70 micron Herschel PACS & SPIRE imaging (pending) WIYN / WHT optical spectroscopy Nobeyama / LMT CO masses (pending)

10 ultra-deep WSRT observations Minimum detectable HI mass: 2x10 9 M! over 150 km/s profile width, with 4! in each of 3 resolution elements. Corresponding limiting column density: 3x10 19 (cm -2 ) over 80 km/s profile width at 7!. hr This requires: 78x12 for A2192 at z=0.188 hr 117x12 for A963 at z=0.206

11 WSRT observational setup Long-term program over 8 semesters A963 A2192 8x10MHz bands, overlapping to cover MHz Z semester = # measurements, surveyed volume " 70,000 Mpc A 20 8x256 channels, covering 18,000 km/s velocity range -B km/s velocity resolution (after Hanning smoothing) pilot study A B 5 dual polarisation, 2-bit correlation, recirculation A B 3 117x 12 hr on Abell 963, 73x 12 hr on Abell A B 15 rms noise per channel: 14 #Jy and 17 #Jy ($V=80 km/s) 5% lost total to RFI, 117 antenna 573 offline (APERTIF prototype) hours Verheijen et al, 2007, ApJ Lett, 668, 9

12 WSRT observational setup Long-term program over 8 semesters 8x10MHz bands, overlapping to cover MHz Z = , surveyed volume " 70,000 Mpc 3 8x256 channels, covering 18,000 km/s velocity range 20 km/s velocity resolution (after Hanning smoothing) dual polarisation, 2-bit correlation, recirculation 117x 12 hr on Abell 963, 73x 12 hr on Abell 2192 rms noise per channel: 14 #Jy and 17 #Jy ($V=80 km/s) 5% lost to RFI, antenna 5 offline (APERTIF prototype) Verheijen et al, 2007, ApJ Lett, 668, 9

13 achieved rms noise in line cubes slightly better than predicted due to lower Tsys at %<1200 MHz elevated noise due to RFI A2192 A963 Flagged: 5-8% 15-17%

14 achieved rms noise in line cubes slightly better than predicted due to lower Tsys at %<1200 MHz before after 12 hr elevated noise due to RFI time A2192 A963 Flagged: 5-8% 15-17% 10 MHz 0 channel 10 MHz channel 0 hr 256

15 RFI increasing over the years...

16 A few words on RFI Z= MHz Z=0 Galileo Z=0.1 Z=0.2 Z=0.3 RFI monitoring campaign at WSRT 1775 MHz

17 continuum maps Abell 2192! = 7 #Jy/beam (confusion limited) SFR " 10 Msun/yr Abell 963! = "12 #Jy/beam (DR limited) ( deep GALEX data more sensitive )

18 Abell 2192 Abell 963! = 17 #Jy/beam! = 14 #Jy/beam $V=80 km/s Detection criteria: 1 x8!, or 1.5x6!, or 2 x5!, or 3 x4! in N consecutive spectral resolution elements.

19 continuum subtraction

20 current state-of-the-art Abell 2192 Abell 963 Verheijen+, in prep Cube size : 9.5 x 9.5 x 325 Mpc 3 Beam size : 65 x 80 kpc 2 x 80 km/s Are Butcher-Oemler clusters accreting a more gas-rich field population?

21 surroundings of Abell Mpc Cube dimensions: 9.5 x 9.5 x 85 Mpc redsihft 0.224

22 Relative HI gas mass fractions MHI = 2x10 9

23 Colour-Magnitude diagram : optical redshifts : HI detections

24 Stacking HI spectra (based on pilot data) Verheijen+ 07 Average HI mass " 2x10 9 M!

25 new WHT/AF2 spectroscopy 40 A963 pre-selected from CMD A redshift 0.30

26 optical redshifts HI detected Abell 963

27 optical redshifts HI detected [OII] emitters Abell 2192

28 examples of 18 galaxies useful for TF study

29 examples of galaxies rejected for TF study

30 TF relations - UMa revisited Mstar from BRIK photometry and Zibetti models. stellar mass baryonic mass Mbar = Mstar + 1.4MHI

31 TF relations - galaxies at z=0.2 BRI mags from dereddened SDSS photometry (InterRest) Mstar from BRI photometry and Zibetti models. stellar mass baryonic mass

32 TF relations - z=0 vs z=0.2 larger scatter no appreciable offset error/statistical analysis is pending stellar mass baryonic mass

33 summary & outlook Expected rms achieved, but significant imaging artifacts HI emission from ~140 individual galaxies at Z"0.2 Blind HI survey uncovers LSS not seen by SDSS Blue BO-galaxies gas-poor wrt similar field galaxies TF Z=0.2 " TF Z=0 Characterization of environments is ongoing Collection and compilation of ancillary data is ongoing