2. Faint Red Galaxies Evolved stars at High Redshift May 28, 2003 P. J. McCarthy UCSC Carnegie Observatories

3. Distant Galaxy Studies in the 20 th Century Focused on faint blue galaxies Samples UV bright populations Traces heavy element production Global census of conversion of gas into stars Evolution of UV luminosity density Madau et al Steidel et al 99

4. Faint Galaxies in the Near Infrared Sensitive to assembly of galaxies via mergers Near-IR offers a window on mass evolution Dust not (as) important Build-up of stellar mass over cosmic time Near-IR luminosity provides proxy for stellar mass Near IR-surveys are technically challenging

5. Optical and near-IR Detectors Large formats: 2k x 4k 3 edge buttable 100 Mpixel FPAs common Cheap - $ 0.01 per pixel 2k x 2k maximum Non-buttable Expensive $ 0.13 per pixel !

6. Challenges facing Deep near-IR Surveys Detectors small and Expensive Cryogenic Optics & baffles required Sky 3 orders of magnitude brighter! Can’t observe when the moon is down!

7. Earliest IR Surveys – New Red population Elston, Rieke & Rieke 1989 10 sq.arcminutes Hu & Ridgeway 1992 100 sq. arcminutes

8. Some EROs are Sub-mm sources Dey et al. 1999 Smail et al. 1999

9. Two Red populations? Moderately red, high surface density on sky Z ~ 1 early types Extreme red colors, very rare Z > 1 Starbursts

10. Las Campanas IR Survey McCarthy, Persson, Martini, Koviak (OCIW) Chen (MIT), Marzke(SFSU), Carlberg, Abraham(UT) Ellis (Caltech), Firth, McMahon, Lahav (IoA) PHASE I: A Carnegie-Cambridge-Toronto Collaboration PHASE II: A Diversified Conglomerate

11. Galaxy Assembly in the 1 < z < 2 Epoch Space density of massive galaxies Stellar evolution in early type galaxies Evolution of 3-D Clustering Growth of massive galaxies and structure GOALS

12. Why Select in the near-IR? Selects on basis of population with high M/L Optical-IR color indices excellent for foreground rejection That where the light is! V I H KZ = 1.5

13. Approach Multi-color optical & near-IR imaging survey Depths keyed to z = 2 elliptical: Ks ~ 21 ! Photometric redshifts Six fields around the celestial sphere 1 square degree Color-Mag Diagrams Color-Redshift Diagrams Number Counts Color-Color Diagrams Luminosity Functions Angular Clustering Morphologies Spectroscopy

14. Phase I: 1 square degree to H = 20.5 + VRI Phase II: 1 square degree to K = 20.8 + BVRIz’JH VRIH survey completed in spring 2001 0.75 square degrees J & K in hand ~10,000 K-selected objects ~70,000 photometric redshifts ~ 350 spectroscopic redshifts Reality Intrudes!

15. CIRSI + LCO Wide Field IR Camera du Pont 2.5m telescope 4 1024 x 1024 arrays cryogenic Offner relay 16 channel electronics

16. 4 1024x1024 detectors – 90% gaps

17. 4 pointings – 16 1024 x 1024 images

20. 13’ x 13’ mosaic – 3 hour exposure 100,000 1024 x 1024 Frames - 30 seconds each

21. Red Galaxies are Abundant V,I,K 80”

22. Photometric Redshifts 8 color photometery BVRIz’JHKs 6 Galaxy templates 1 AGN, 128 stellar templates Best fit template and redshift Likelihood function See Koo 1985 Connolly et al 1995,1997

23. Photometric Redshifts from LCIR Chen et al 2002

24. Photometric Redshifts from LCIR Recent update GMOS redshifts

25. Basic Phenomenology: Sky density, Space Density, Luminosity & Color Evolution

26. IR to Optical Color Selection I-K > 4 Rejects z < 1 Foreground & late types at all redshifts

27. IR to Optical Color Selection I-K > 4 Rejects z < 1 Foreground & late types at all redshifts

28. Color-Magnitude Diagram Stars 0.0 < z < 1.0 1.0 < z < 1.5 1.5 < z < 2.0 2700 sq. arcmin

29. Classical Star Counts

31. Number-Magnitude Relations I-K > 4.0 I-K > 4.5 I-K > 5.0

32. Number-Magnitude Relations I-K > 4.0 I-K > 4.5 I-K > 5.0 Gardner et al K-band LF

33. UV & Optical Color Diagnostics V I H KZ = 1.5 Optical to IR color sensitive to old population I-K Rest-frame UV slope sensitive to recent star formation V-I

34. Color-Color Diagrams Stars form distinct sequence K < 17.5

35. Color-Color Diagrams Stars form distinct sequence K < 18.5

36. Color-Color Diagrams Stars form distinct sequence Z > 1 galaxies appear at K ~ 19 K < 19.5

37. Color-Color Diagrams Stars form distinct sequence Z > 1 galaxies appear at K ~ 19 Z > 1.5 galaxies at K ~ 20 K < 20.8

38. Color-Color Diagrams Stars form distinct sequence Z > 1 galaxies appear at K ~ 19 Z > 1.5 galaxies at K ~ 20 Reddest galaxies follow minimal evolution track K < 20.8

39. Evolving Luminosity Functions Chen et al. 2002 Redshift errors must be explicitly treated! Luminosity functions from photometric redshifts

40. Evolving Luminosity Functions LFs derived from photo- z’s with modified likelihood approach LF at intermediate z agrees well with CNOC2 Very little apparent evolution in L* to z ~ 1.2 Chen et al. 2002

41. R-band Luminosity Density Rest-Frame R-band Luminosity density little or no evolution to z ~ 1.2

42. Clustering: A proxy for merging Tags populations at high and low redshift

43. Angular vs. 3-D Clustering

44. Clustering of Red Galaxies

45. Angular Clustering Clustering amplitude of red galaxies is 20 x that of the full field

46. Angular Clustering  = 12” I – K > 4  = 1” All K < 20.5

47. Angular Clustering Clustering amplitude higher for redder colors and brighter magnitudes.  = 30” K ~ 18 & I-K > 5 n(z) required for r_0

48. Inversion of  to r 0  All I-K K > 19 0.7  I-K > 4 19 1.0  I-K > 4 18 1.0  ’’ I-K > 5 18 1.2 Generalized Limber equation:

49. n(z) for I-K selected subsamples

50. Inversion of  to r 0  All I-K K > 19 0.7 5 h -1 Mpc  I-K > 4 19 1.0 9  I-K > 4 18 1.0 9  ’’ I-K > 5 18 1.2 10 Generalized Limber equation:

51. Evolution and Color Dependence Red color selection or E morphological selection Blue color selection or late type morphological selection LCRS CNOC2 CFRS CFGRS LBG

52. Evolution and Color Dependence Kauffmann et al 99 Early types Star forming galaxies LCRS CNOC2 CFRS CFGRS LBG

53. Morphology: What type of Galaxy are we talking about after all?

54. E/S0 Template Match Giavalisco et al Cycle 11 Treasury Program 10/5/02 public release 91 objects

55. Giavalisco et al Cycle 11 Treasury Program 10/5/02 public release Sab/Sbc Template Match

56. Giavalisco et al Cycle 11 Treasury Program 10/5/02 public release 54 objects E/S0 Template Match

57. Giavalisco et al Cycle 11 Treasury Program 10/5/02 public release Sab/Sbc Template Match

58. Morphologies of Red Galaxies 4.0 = 1.0 Template type 1 (E/S0) 85% Compact 10% Disks 5% Diffuse Template type 2 (Sab/Sbc) 60% Compact 35% Disks 5% Diffuse Template type 1 (E/S0) 60% Compact 25% Disks 15% Diffuse Template type 2 (Sab/Sbc) 40% Compact 30% Disks 30% Diffuse 4.5 = 1.2 See Stiavelli & Treu 1999 NICMOS results See Yan & Thompson 2002 WFPC2 results

59. Spectroscopy: Real redshifts and Spectral Diagnostics

61. Conventional Slit Spectroscopy Sky subtraction is primary limitation –Slit irregularities –Flat-field errors –Residual Fringing –Geometric distortions –Low slit density on sky Beam switching ? –Variable sky spectrum –Read noise penalty –High read-out overhead The solution: ‘nod & shuffle’ Glazebrook & Bland-Hawthorn 99

62. Sky cancellation: ‘nod and shuffle’ Storage of ‘sky’ image next to object image via ‘charge shuffling’ Zero extra noise introduced, rapid switching (60s) A B ABAB Typically A=60s/15 cy: 1800s exposure  10  subtraction

63. GMOS N&S Sky residuals SUMMED along long slit (1.8 arcmin) Raw Sky/20 Subtracted sky (i.e. ~10  level is enough for 200,000 sec pointed obs.) Cycle: A=60s B=60s + 25s o/head

64. Gemini + GMOS GMOS spectrograph Gemini GMOS LRIS LDSS1 GMOS on Gemini North 5’ x 5’ FOV R ~ 800

65. GDDS Spectra 77 objects 40,000 secs

66. [OII] Redshifts from GDDS 23.7 < I(AB) < 24.2

67. Absorption Line Spectra I = 24.0 Z = 1.67 I = 23.7 Z = 1.56 I = 24.2 Z = 1.39 Rest Wavelength

68. Interstellar Matter at z = 1.5 Red: Local Star burst composite (Tremonti et al.) Black: GDDS z = 1.5 I ~ 24.5 I-K < 3 composite

69. Interstellar Matter at z = 1.5

70. Gas Rich! DLAs Savaglio et al. 2003

71. K + A Galaxies Only 1 in 10,000 galaxies in LCRS have similar EWs

72. K + A Galaxies >45% burst by mass with 500My age ~5% of red galaxies are in this class!

73. The Reddest Galaxies

75. Glazebrook et al in prep

76. Color Evolution Photometric RedshiftsSpectroscopic Redshifts

77. Color Evolution Redshift desert is nearly gone……

78. Conclusions Counts: little density evolution to z ~ 1.2 LFs: R-band Luminosity density declines by < x 2 to z ~ 1.5 UV colors: wide range of star formation levels Clustering: Strong clustering consistent with local E population Morphologies: Predominantly early types Spectroscopy: Old & Intermediate age populations The Progenitors of Early Type Galaxies

79. Conclusions Population of massive field early types largely unevolved since z ~ 1.5 The Future ACS imaging of the GDDS Fields IMACS with its 27’ x 27’ and Nod & Shuffle with > 1000 slits per mask: Large Scale Structure at z ~ 1.5