1. Will the Dark Energy Survey measure neutrino masses? http://www.darkenergysurvey.org Will the Dark Energy Survey measure neutrino masses? http://www.darkenergysurvey.org http://www.darkenergysurvey.org Outline DES: what is it and update + probes used Neutrino masses from DES

2. The Dark Energy Survey (DES) Proposal: ◦ Perform a 5000 sq. deg. survey of the southern galactic cap ◦ Measure dark energy with 4 complementary techniques New Instrument: ◦ Replace the PF cage with a new 2.2 FOV, 520 Mega pixel optical CCD camera + corrector Time scale: ◦ Instrument Construction 2008-2011 Survey: ◦ 525 nights during Oct.–Feb. 2011-2016 ◦ Area overlap with SPT SZ survey and VISTA VHS Use the Blanco 4m Telescope at the Cerro Tololo Inter-American Observatory (CTIO)

3. The DES Collaboration an international collaboration of ~100 scientists from ~20 institutions US: Fermilab, UIUC/NCSA, University of Chicago, LBNL, NOAO, University of Michigan, University of Pennsylvania, Argonne National Laboratory, Ohio State University, Santa-Cruz/SLAC Consortium Observatorio Nacional, CBPF,Universidade Federal do Rio de Janeiro, Universidade Federal do Rio Grande do Sul Brazil Consortium: UK Consortium: UCL, Cambridge, Edinburgh, Portsmouth, Sussex, Nottingham Spain Consortium: CIEMAT, IEEC, IFAE CTIO

4. DES Organization Supernovae B. Nichol J. Marriner Clusters J. Mohr T. McKay Weak Lensing B. Jain S. Bridle Galaxy Clustering E. Gaztanaga W. Percival Photometric Redshifts F. Castander H. Lin Simulations A.Kravtsov A. Evrard Theory W. Hu J. Weller Strong Lensing E. Buckley-Geer M. Makler Galaxy Evolution R. Wechsler D. Thomas QSOs R. McMahon P. Martini Milky Way B. Santiago B. Yanny 11 Science Working Groups Over 100 scientists from the US, UK, Spain and Brazil

5. The DES Instrument: DECam DECam Focal Plane 3 sq. deg. field of view (~ 0.5 meter diameter focal plane) 62 2kx4k Image CCDs: 520 MPix 8 2kx2k Alignment/focus CCDs 4 2kx2k Guide CCDs

6. The 5 lenses are now being polished C2 Polishing & coating coordinated by UCL (with 1.7M STFC funding) C1 Design: 5 lenses Largest is~ 1m diameter Smallest is ~ 0.5m Polishing started in May 2008 Est. Delivery May 2010

7. DES CCDs 62 2kx4k fully depleted CCDs: 520 Megapixels Excellent red sensitivity Developed by LBNL

8. Full size prototype imager used for integration testing out at Sidet (Fermilab)

9. 9 DECam parts in Fabrication: Shutter Bonn University and Argelander Institute in Germany is making the DES Shutter Opening is ~ 600mm diameter The DECam Shutter is the largest ever (so far)

10. Earthquake!!! No damage to telescope Given that and timeline of CCD’s and corrector -> first light should be late next year

11. Dark Energy Science Program Four Probes of Dark Energy Galaxy Clusters clusters to z>1 SZ measurements from SPT Sensitive to growth of structure and geometry Weak Lensing Shape measurements of 300 million galaxies Sensitive to growth of structure and geometry Large-scale Structure 300 million galaxies to z = 1 and beyond Sensitive to geometry Supernovae 15 sq deg time-domain survey ~3000 well-sampled SNe Ia to z ~1 Sensitive to geometry Plus QSOs, Strong Lensing, Milky Way, Galaxy Evolution

12. Synergy with VISTA DES recovers V in VISTA! DES will provide the visible and Vista the IR counterpart

13. DES griz DES 10  Limiting Magnitudes g24.6 r24.1 i24.0 z23.9 +2% photometric calibration error added in quadrature Galaxy Photo-z Simulations +Developed improved Photo-z & Error Estimates and robust methods of outlier rejection Cunha, Lima, Frieman, Lin and Abdalla, Banerji. Lahav Z 23.8 Y 21.6 +VHS DES griZY +VHS JHKs on ESO VISTA 4-m enhances science reach *Vista Hemisphere Survey J 20.3 H 19.4 Ks 18.3 ANNz; low depth survey: training sets in place

14. DES Forecasts: Power of Multiple Techniques Assumptions: Clusters:  8 =0.75, z max =1.5, WL mass calibration BAO: l max =300 WL: l max =1000 (no bispectrum) Statistical+photo-z systematic errors only Spatial curvature, galaxy bias marginalized, Planck CMB prior w(z) =w 0 +w a (1–a) 68% CL geometric geometric+ growth DETF Figure of Merit: inverse area of ellipse Stage II not included here

15. DES will also constrain the neutrino mass We have made simulations for this with Des photometric redshifts We have also measured this from the current SDSS survey. (cosmological results presented by Thomas Tues.) I will go through the assumptions and present the forecasts.

16. Neutrinos as Dark Matter Neutrinos are natural DM candidates They stream freely until non-relativistic (collisionless phase mixing) Neutrinos are HOT Dark Matter First structures to be formed when Universe became matter -dominated Ruled out by structure formation CDM Neutrino Free Streaming  b, cdm

17. Measuring the clustering with Photo-z Photo-z distribution

18. Looking at techniques in real data: The 2SLAQ & MegazLRG. (Pathfinder with DES) 2SLAQ galaxies selected from the SDSS survey. Mainly red galaxies at redshift ranging from 0.4 to 0.7. Even though photo-z are good for LRG given large 4000A break different techniques give different accuracies 13000 galaxies from 2SLAQ. ~8000 for training ~5000 to calibrate the histogram Abdalla et al 08

19. DES+VISTA would improve photo-z by a factor of 2 for z> 1 What is the effect on WL, BAO, SNIa Science? Banerji, Abdalla, OL & Lin 0711.1059 DES (5 filters) vs. DES+VISTA(8 filters)

20. Already seen earlier this week Thomas et al. 0911.5291 WMAP red: bound is ~1.3eV. (all 95%) + BAO+SNe: blue 0.69eV + MegaZ : yellow 0.65eV + BAO+SNe+MegaZ+HST: green 0.28eV

21. Neutrino mass from DES+Planck Lahav, Kiakotou, Abdalla and Blake (0910.4714) DES + Planck 5 times more constraining than WMAP + MegaZ DES will have many galaxy types (~30 or so) to do this experiment -> important for galaxy bias Two simulations used: Input: M =0.05 eV and 0.25eV Error: 0.12 eV 95% (Only DES + Planck) on both simulations. Without any further data (BAO, SNe, clusters, etc…)

22. Total Neutrino Mass DES vs. KATRIN M < 0.1 eV M < 0.6 eV t Goal: 0.05 eV Other cosmological probes of the neutrino mass: weak lensing, CMB lensing, etc…

23. Conclusions DES under construction: ◦ Lenses being polished ◦ CCD’s being tested ◦ Should have first light late next year Science predicts a increase in our knowledge in w0-wa plane Also increase in our knowledge in the neutrino mass: ◦ Same experiment done on SDSS LRG’s m_nu < 0.28eV ◦ For DES m_nu < 0.12eV with Planck only. ◦ All these have to be taken with a pinch of salt… but…