Status of the Spitzer Warm Mission Spitzer Extended Deep Survey (SEDS)

1. Status of the Spitzer Warm MissionSpitzer Extended Deep Survey (SEDS) AEGIS Meeting, Toledo Spain Giovanni G. Fazio Harvard Smithsonian Center for Astrophysics and the SEDS Team

2. SEDS: Spitzer Extended Deep Survey • PI: Giovanni Fazio • 47 Co-I’s from 23 institutions • Primary Scientific Objective • Galaxy formation in the early Universe • Obtain first complete census of the assembly of stellar mass and black holes as a function of cosmic time back to the era of reionization • Series of secondary objectives • Unbiased survey 12 hrs/pointing at 3.6 and 4.5 microns ([3.6] = 26 AB, 5 ) in five well-studied fields (0.9 sq deg) • 10 times area of deep GOODS survey • Total Time: 2108 hrs over 1.5 years • No proprietary time on data

3. SEDS Co-Investigators Harvard Smithsonian Center for Astrophysics:Lars Hernquist, Matt Ashby, Jiasheng Huang, Kai Noeske, Steve Willner, Stijn Wuyts, T.J. Cox, Yuexing Li, Kamson Lai Max-Planck-Institut für Astronomie: Hans-Walter Rix, Eric Bell, Arjen van der Wel University of Califronia, Santa Cruz: Sandy Faber, David Koo, Raja Guhathakurta, Garth Illingworth, Rychard Bouwens NASA/GSFC: Sasha Kashlinsky, Rick Arendt, John Mather, Harvey Moseley Carnegie Observatories: Haojin Yan, Ivo Labbe, Masami Ouchi University of Pittsburgh: Jeff Newman Space Telescope Science Institute: Anton Koekemoer University of Arizona: Ben Weiner, Romeel Dave, Kristian Finlator, Eiichi Egami University of Western Ontario: Pauline Barmby Imperial College, London: Kirpal Nandra

4. SEDS Co-Investigators University of Chicago/KICP:Brandt Robertson Swinburne University: Darren Croton Stanford University/KIPAC: Risa Wechsler University of Florida, Gainesville: Vicki Sarajedini Astrophysikalisches Institute, Potsdam: Andrea Cattaneo University of Massachusetts, Amherst: Houjun Mo Royal Observatory Edinburgh: James Dunlop Institute of Astronomy and Astrophysics, Academia Sinica, Taiwan: Lihwai Lin National Research Council, Herzberg Institute of Astrophysics: Luc Simard Texas A&M University: Casey Papovich Tohoku University, Japan: Toru Yamada Oxford University: Dimitra Rigopoulou University of California, Riverside: Gillian Wilson

5. SEDS: Scientific Objectives • Galaxy Assembly in the Early Universe • Direct study of the mass assembly back to the era of reionization. • Study stellar masses and mass functions from z = 4 - 6 • Constrain high mass end of mass function at z = 7. • Measurement of spatial clustering of galaxies • Determine the evolution of galaxy properties as a function of halo masses. • Study of identified Ly emitters at z = 5 - 7. • High z counterparts to dwarf galaxies? • Different sample compared to dropouts • Black hole evolution at z > 6. • Study of high-z AGN number counts (constrain evolutionary models) • Relationship to stellar growth • Tests of theoretical models of galaxy assembly • Numerical simulation models to tie observational effects together

6. SEDS: Scientific Objectives • Auxiliary Science • Galaxy Evolution from z ~ 1 - 4 • Nature of high-z galaxies • Mass assembly of galaxies • Emergence of quiescent galaxies • Mid-infrared Variability for AGN Identification • A more universal tracer of AGN • Measurement of the Cosmic Infrared Background radiation spatial fluctuations

7. SEDS: Technical Aspects • Sensitivity • 12 hrs/pointing at 3.6 and 4.5 microns • [3.6] = 26 AB, 5  (0.15 Jy) • Robustly measure M* (reach 5 x 109 Msun at z = 6) • Field Geometry and Configuration • Clustering and large scale structure at z = 6: > 20 - 30 arcmin • Correlation length: > 5 - 10 arcmin • Number of Fields • Cosmic variance: 5 fields • Field Selection • Fields with deep auxiliary data: Extended GOODS-S, Extended GOODS-N, UDS, EGS, COSMOS/UltraVista

8. SEDS Survey Fields

9. Area Coverage vs Exposure Time

10. SEDS: Technical Aspects • Expected Number of Sources • Statistically meaningful samples • Enough to derive mass functions and perform clustering studies • Finlator models: 8000, 2000, and 200 at z = 5, 6, and 7; few at z ~ 9. • Source Selection • Conventional Ly “dropout” technique • Z = 4, 5, 6, and 7: B, V, i, and z

11. Timeline of Warm Mission Events • Original IWIC plan affected by unexpected thermal control issues. Significant delay while reworking IRAC thermal control system. • Cryogen exhausted 15 May 2009 22:11:27 UTC • IRAC Warm Instrument Characterization (IWIC) begins 19 May 2009 • - Anomaly with IRAC thermal control  Standby mode entry 19 May 2009 23:35:48 • - Observatory returned to normal mode 20 May 2009 • - Firmware patch initiated • Transition science (GRB image) and instrument characterization during patch development • Firmware patched and IWIC restarted 19 June 2009 • - Temperature setpoint of 31 K and applied bias of 450 mV selected 03 July • IWIC completed 28 July 2009 It became apparent that the IRAC heaters were driving the MIC temperature higher than power-off equilibrium.

12. Timeline of Warm Mission Events • 12 Aug 2009 -- array heaters switched off • Permitted operation 1.3 K cooler than original setpoint; critical noise boundary • 18 Sep 2009 -- Final operating setpoints established • 500 mV applied bias, T(array) = 28.7 K; final MIC temperature expected to be 27.5K • 23-30 Sep 2009 Recalibration sequence conducted • Flat-field, linearity, bias, photometric calibrations • 29 Sep 2009 -- First campaign 2 wks of data released to observers • 12 Oct 2009 -- 6th campaign released back on normal 14 day after campaign ends release cadence

13. Spitzer Warm MissionVariances from the Expected • Bad surprises • - Linearity very different than cryogenic • - Appearance of intermediate term latents • Column pulldown slightly more complicated •  Good surprises • - No long term latents at 3.6 m • - No muxbleed and muxstripe • We have not derived the first-frame correction yet, but have the data in hand • As expected • - Optical performance remains the same • - 3.6 and 4.5 m performance close to cryogenic • - AOT worked as expected • - Pipeline performed as in cryogenic mission IWIC calibration and characterization of greater depth and complexity of the IRAC characterization during the original In-Orbit Checkout

14. Warm IRAC Performance • Deep image noise performance • From dark measurements • 3.6 mm 12% worse than cryo • 4.5 mm 10% better than cryo • 10% uncertainty in values • Bright source limit • S/N ~ (throughput)0.5 • 3.6 mm 5% lower than cryo • 4.5 mm 2% lower than cryo Absolute Calibration • Currently 5% absolute calibration uncertainty compared to 3% at end of cryo mission • Performance supports all warm mission science

15. Data Calibration Flatfield – currently recalibrated to better than cryo (0.2%). Darks – recalibrated similarly to cryo. More sturcture than previously, but subtracts well. Linearization – calibrated at 5% level, difficult to measure, but plan to solve this is underway. Flux Calibration – currently at few % level, will get better with time as routine calibrations build. First-Frame Effect – data taken, effect is relatively small for the InSb. Pixel-Phase Correction– larger than cryo, but significant characterization data taken. Instrument calibration load down to about 4% of total observing time.

16. Warm vs. Cryogenic: Deep Imaging of EGS Warm 3.6 m Cryo 3.6 m Warm 4.5 m Cryo 4.5 m

17. 5 UDS Field (20 x 20 arcmin) 3.6 micron 4.5 micron

18. UDS Field (5 x 5 arcmin) 3.6 micron 4.5 micron

19. Planetary Nebulae NGC 4361 NGC 2899

20. Star-Forming Regions Cygnus DR22

21. Summary • Warm IRAC sensitivity comparable to cryogenic • IRAC data quality / sensitivity support all current and planned warm science • Pipelines functional (absolute calibration currently ~5%) • Science quality data flowing to the community • Continuing analysis (linearity, bias, absolute calibration) will improve data quality • Anticipate update to warm calibration and data reprocessing by first of year • Currently completed one epoch of SEDS data: UDS field (4 hrs) • Next SEDS observations: EGS and COSMOS/UltraVista