1. Elizabeth Stanway - Obergurgl, December 2009 Lyman Break Galaxies as Markers for Large Scale Structure at z=5 Elizabeth Stanway University of Bristol With Malcolm Bremer, Luke Davies, Matt Lehnert, Mark Birkinshaw, Chris Carilli, Alain Omont

2. Elizabeth Stanway - Obergurgl, December 2009 The ESO Remote Galaxy Survey VRI image of CL1037-1243 Targets the 10 EDisCS Survey cluster fields (VRIJK) Adds Z band imaging and 100hrs of spectroscopy Also Spitzer/IRAC photometry 20 VLT/FORS2 Slitmasks Targets R-drops with R-I>1.3, I AB <26.3, z~5 R~660, ~6500-10000Å (Douglas et al, 2009, 2010)

3. Elizabeth Stanway - Obergurgl, December 2009 Better than 80% spectroscopic completeness for dropout candidates Reasonable S/N on continuum 68 Confirmed Redshifts at 4.4<z<6.4 including: 35 Lyman-  emission lines 33 redshifts determined from Lyman breaks (18 class A, 13 B) The ESO Remote Galaxy Survey

4. Elizabeth Stanway - Obergurgl, December 2009 Tip of an Iceberg? These structures may extend beyond the limits of the imaging fields One of the fields shows evidence for spatial as well as redshift clustering Redshift precision is better than 0.002 The redshift spikes are not in skyline-free wavelength regions 500 kpc Examples of Lyman Break galaxy spectra in the z=5.00 field Overdensities at z=5.00 and z=5.15

5. Elizabeth Stanway - Obergurgl, December 2009 Moving to Longer Wavelengths High Redshift Galaxies at Millimetre Wavelengths At z=5, 850  m is close to the dust emission peak (i.e. negative K-correction starting to break down in sub-mm) Molecular gas is traced at all redshifts by CO emission The fundamental rotational transition of CO is at 115.271 GHz CO(1-0) at z=5 is in the 12mm/K band CO(2-1) emission at z=5 and CO(3-2) at z=8 are both in the 7mm/Ka band CO(5-2) emission at z=5 is in the 3mm band Also - [CII] is a promising emission line, particularly in low metallicity systems, and can be observed in the 1mm band at z=5-6

6. Elizabeth Stanway - Obergurgl, December 2009 Cool Gas at High Redshift Pilot test –Single pointing at ATCA –24 hours at 12mm –44 hours at 7mm –Bandwidth  z~0.03 (240 MHz) Limiting Sensitivity – 0.11 mJy/Beam at 12mm, 0.10 mJy/Beam at 7mm (in 30 km/s) Angular Resolution –16x10’’ at 12mm, 7x5’’ at 7mm

7. Elizabeth Stanway - Obergurgl, December 2009 Cool Gas at High Redshift (Stanway et al, 2008)

8. Elizabeth Stanway - Obergurgl, December 2009 Cool Gas at High Redshift No detection from LBGs in field => M H2 <2x10 9 M sun BUT Strong line emission from optically-faint source at 37.64GHz Likely CO(2-1) at z=5.1245±0.0001  M H2 =2x10 10 M sun

9. Elizabeth Stanway - Obergurgl, December 2009 Confirming the Line Reobserved at the NRAO Green Bank Telescope in May 2009 Observations shallower than planned Source redetected at 3  Flux and velocity width consistent with ATCA values

10. Elizabeth Stanway - Obergurgl, December 2009 LABOCA Observations APEX/Laboca Observations 11hrs, June-July 2009, Image r.m.s. = 2.8 mJy No significant detections of CO Emitter source No detections of LBGs in field Intensity Coverage 5 arcmin

11. Elizabeth Stanway - Obergurgl, December 2009 Dust Limits on Cluster LBGs Laboca image covers 4x4 arcmin 2 at 90% depth Can obtain a limit on the dust mass for spectroscopically confirmed z=5 Galaxies in this field M stars ~ few x 10 9 M  in these sources M H2 < few x 10 9 M  (2  ), based on CO line non-detection M dust < few x 10 8 M  (2  limit) at reasonable temperatures

12. Elizabeth Stanway - Obergurgl, December 2009 Dust Limits on the CO Source M dust < 5 x 10 8 M  (2  limit) at 30K from LABOCA M dust < 2 x 10 8 M  (2  limit) at 30K from MAMBO 1.2mm and 850  m limits consistent except at high temperatures (T≈100K) M gas /M dust > 100

13. Elizabeth Stanway - Obergurgl, December 2009 MAMBO Observations IRAM 30m MAMBO Observations in April 2009 (4hr) S 1mm = -0.278 ± 0.438 mJy Implies L’ CO /L FIR ratio more akin to lower redshift star- forming galaxies than ULIRGs/SMGs/QSO hosts Figures modified from Solomon & vanden Bout (2005)

14. Elizabeth Stanway - Obergurgl, December 2009 Constraints on the SED SED rules out gas-to- dust ratios typically seen in ULIRGs and QSO hosts at high z. More like local star- forming galaxies - Normal not exceptional SF galaxy. ALMA will be able to do this work trivially

15. Elizabeth Stanway - Obergurgl, December 2009 Constraints on the SED SED rules out gas-to- dust ratios typically seen in ULIRGs and QSO hosts at high z. More like local star- forming galaxies - Normal not exceptional SF galaxy. ALMA will be able to do this work trivially

16. Elizabeth Stanway - Obergurgl, December 2009 Our 2009 ATCA Survey Targeted second LBG over-density covering 3 times as much area at 37Ghz and 2 GHz bandwidth Encompasses 7 LBGs in  z~0.1 range (around z~4.95), and 1 other z=5.2 source. Observed each pointing for 2 nights using the ATCA with two 2GHz IFs and 1MHz resolution (at 37GHz). Redshift coverage of ~4.23-5.34 at 19GHz and ~4.81-5.44 at 37GHz. RMS limits ~0.2mJy/beam at 19GHz ~0.3mJy/beam at 37GHz (in 1 MHz channels)

17. Elizabeth Stanway - Obergurgl, December 2009 Preliminary Results 6 Possible detections within the ATCA primary beams. Three detected at 19GHz and three at 37GHz. One has possible 19 and 37GHz detection. 3 would fall within the redshift of the over-density. Two are closely separated in redshift at z~4.6. Gas masses (H 2 ) ~ 3-6 x10 9 M  for 37GHz detection and ~ 3-6 x10 10 M  for 19GHz detections. FWHM ~50-120kms -1.  Comparable to previous detection.

18. Elizabeth Stanway - Obergurgl, December 2009 z=4.92 3x10 9 M sun in H 2 May be detected in two CO transitions Peak flux 0.4 mJy  v = 50 km/s Preliminary Results

19. Elizabeth Stanway - Obergurgl, December 2009 Limits on LBGs in the Field All LBGs are not detected at 19GHz or 37GHz. Image R.M.S. Noise ~ 0.16mJy/beam (at CO(1-0) line) ~ 0.37mJy/beam (at CO(2-1) line) Gives 2  detection limit ~ L CO < 2.8x10 10 K kms -1 pc 2 ~ L CO < 1.7x10 10 K kms -1 pc 2 For an unresolved 200 kms -1 emission line at the redshifts of the galaxies.  Can constrain molecular gas in LBGs in the field to: M(H 2 )<2.2x10 10 M  (2 , CO(1-0)) M(H 2 )<1.4x10 10 M  (2 , CO(2-1)) Total observed mass in stellar component and H 2 ~1.3x10 11 M  in 33.8Mpc 3

20. Elizabeth Stanway - Obergurgl, December 2009 Conclusions Lyman Break Galaxies clearly mark out underlying structure at very high redshifts Regions overdense in LBGs are perfect for follow-up at over wavelengths Molecular Gas may contribute a substantial fraction of the the baryon mass at z=5 CO emission lines are currently the most accessible probe of this Searches for dust and gas dominated galaxies at high z are possible with current instrumentation with several promising candidates already identified ALMA will enable more complete surveys of the baryon distribution in high z large scale structure

21. Elizabeth Stanway - Obergurgl, December 2009 Blank Slide