1. R. PainEDEN, Dec 7 20051 Reynald Pain LPNHE, Univ. Paris, France Probing Dark Energy with Supernovae

2. R. PainEDEN, Dec 7 20052 Dark Energy with SNe : an active field 2003 1998 Today 2015? ?

3. R. PainEDEN, Dec 7 20053 Outline Why/how supernovae ? Past and more recent SN constraints Today’s landscape Expected constraints from Future SN programs

4. R. PainEDEN, Dec 7 20054 Cosmology with SNe Ia

5. R. PainEDEN, Dec 7 20055 SNe Ia are not standard candles Very Luminous events  visible at cosmological distances Show little intrinsic dispersion

6. R. PainEDEN, Dec 7 20056 SNe Ia Show Light Curve Shape Relationships (similar to Cepheids P-L relation) => Allows us to measure distances to better than 5-8% precision Measuring distances

7. R. PainEDEN, Dec 7 20057 ModelsObservations Using radiative transfer codes, this relationship is reproduced simply by increasing the abundance of 56 Ni in the explosion. Here this is characterized by increasing the effective temperature of the atmosphere. SNe Ia modelisation

8. R. PainEDEN, Dec 7 20058 Past and more recent SN projects ~1990->1998 : pioneer work : find distant SNe, measure LC, z => Discovery of the acceleration of the expansion of the Universe 1999 -> 2004 : More supernovae, higher redshifts Study of systematics (measure color, host galaxy types HST follow-up observations Search/discoveries with HST => confirmation, first constraints on w

9. R. PainEDEN, Dec 7 20059 1998: first (precise enough) results 2 (independent) groups (High-z Team and SCP) present new results based on 42 (SCP) and 10 (HZT) high-redshift SNe and 20-40 low-redshift SNe.

10. R. PainEDEN, Dec 7 200510 1998 : HZT & SCP first “constraint” on w w (cste, flat Universe) < -1/3 (99% CL)

11. R. PainEDEN, Dec 7 200511 2003 : HST measured color SCP 2003 +11 SN photometrically followed with HST  allows event by event extinction correction Updated Hubble diagram Using a low extinction subset

12. R. PainEDEN, Dec 7 200512 SCP 2003 (Knop et al.) +CMB+2dF : w = -1.05+0.15-0.20 (stat) +/- 0.09 (syst)

13. R. PainEDEN, Dec 7 200513 2003 results from HZT (Tonry et al.) Hubble diagram of ~230 published SNe (70 z>0.3)  M,   =0.3, 0.7 0.3, 0.0 1.0, 0.0

14. R. PainEDEN, Dec 7 200514 HZT 2003 (Tonry et al.) -1.48 < w < -0.72 at 95% confidence Assuming flat universe and  M from 2dF

15. R. PainEDEN, Dec 7 200515 SNe at higher redshift (Goods/ACS survey) Probe the deceleration era Find SN at z>1.2 using HST

16. R. PainEDEN, Dec 7 200516 GOODS/ACS 2004: HST Supernovae Expansion went from deceleration to acceleration Exclude grey dust

17. R. PainEDEN, Dec 7 200517 HST SNe : Riess et al. 2004 (GOODS/ACS) - w (flat+CMB+LSS) = -1.02 +0.13 - 0.19 (w<-0.76 95%CL) - first “constraints” on w’

18. R. PainEDEN, Dec 7 200518 1990-2004: the discovery phase The « 1st generation » High-z SN projects (SCP, HZT, HHZT) have o(200) SN Ia up to z=1.7 (about 20 above z=1). The projected statistical uncertainties will match estimated level of systematic uncertainties  Need « 2nd generation » experiments with both high statistics o(1000) and better control of possible systematics Both for high-redshift and low-redshifts SNe

19. R. PainEDEN, Dec 7 200519 SNe Ia : Today’s landscape low-z (z<0.1): Cfa (Harvard, UCB,...) Carnegie (+IR) SN Factory/SNIFS z ~ 0.1-0.3 : SDSS/SN high- z: ESSENCE SNLS ACS/HST : PANS (Riess et al) Clusters (Perlmutter et al)

20. R. PainEDEN, Dec 7 200520 SNLS – The SuperNova Legacy Survey

21. R. PainEDEN, Dec 7 200521 Imaging observing strategy : “Rolling Search” Each lunation (~18 nights) : repeated observations (every 3-4 night) of 2 fields in four bands (griz)+u for as long as the fields stay visible (~6 months) for 5 years: expected total nb of SN : ~2000 (detected)

22. R. PainEDEN, Dec 7 200522 SNLS :example of 2nd generation high-z survey SNLS-04D3fk z=0.3578 SNLS-04D3gx z=0.91 As of Nov 15, 2005 : 226 SNe Ia+ Ia? Expect ~700 by survey end (2008.5)

23. R. PainEDEN, Dec 7 200523 SNLS First year Hubble diagram Final sample : 45 nearby + 71 SNLS SN In a w=-1 Flat  CDM universe:  M = 0.263 +/- 0.042 (stat) +/- 0.032 (syst)

24. R. PainEDEN, Dec 7 200524 SNLS first year constraint on Dark Energy solid contours : SNLS dotted contours : Baryon Acoustic Peak (BAO), Eisenstein 2005 (68.3, 95.5 and 99.7% CL)  M = 0.271 +/- 0.021 (stat) +/- 0.007 (syst) w = -1.023 +/- 0.090 (stat) +/- 0.054 (syst)

25. R. PainEDEN, Dec 7 200525 Future SN programs SNLS/ESSENCE and planned 4m surveys Other future ground based projects Space projects

26. R. PainEDEN, Dec 7 200526 Future SN programs By 2008-9 SNLS/ESSENCE + Nearby SNe should reach :  w (cte)~0.07 - no (significant) constraints on w’ (wa) will reach a new (theirs) systematic floor also very difficulty with upcoming 4m Wide Field projects : DES, DarkCam

27. R. PainEDEN, Dec 7 200527 Future ground based SN projects Pan Starrs : Simultaneous observing with Four 1.8m telescopes of 3 deg2 fov (0.3’’ pixels) LSST : One 8m telescope with 9 deg2 fov => 250000 SN/an !

28. R. PainEDEN, Dec 7 200528 Precision cosmology with SN Ia Detect/follow SN Ia from Space e.g. SNAP Proposed 1999 Now running/waiting for NASA/DOE JDEM AO (2007+)

29. R. PainEDEN, Dec 7 200529 Lightcurves and Spectroscopy from space - Multicolor high S/N lightcurves up to z~2 - SN spectral identification up to redshifts z~1.7

30. R. PainEDEN, Dec 7 200530 SNAP: strategy - precision on w Area : 2x7.5 sq. deg. Cadence : 4 days Total duration : 3 yr 60% imaging - 40% spectro Total nb of SN : ~ 2000 contraints on w vs  M (statistics + systematics) + 300 nearby SNe z>0.1

31. R. PainEDEN, Dec 7 200531 SNAP: probing DE models  w´= 0.08  w 0 = 0.05

32. R. PainEDEN, Dec 7 200532 JDEM/DESTINY Selected by NASA for « Einstein Probes 2yr Conceptual Studies »  =1.8m telescope 0.25 deg. carrés - NIR 0.9->1.7  all grism R=100 (spectrophotometry) L2 orbit Survey: 4 h exposure 7.5 sq. deg. 1.5 sq. deg./day (cadence 5 days) 2000 SNe 0.5<z<1.7 in 2 yrs Calibration with ESSENCE/LSST (z<1)

33. R. PainEDEN, Dec 7 200533 Dark Universe Explorer (DUNE) Proposed (2004) as weak lensing probe 1.2 m telescope 0.5 sq. deg. Imager visible only - 1 filter Currently in phase O study at French Space Agency If approved.. launch by 2011-12 ? A SN program for DUNE 2x60 sq deg. (UBVRIZ, I=26) - cadence: 4days Photométric id of SNe (UBV restframe) Ground based spectroscopy (host galaxies) => 10000 SNe 0.1<z<1 in ~18 months statistical uncertainties on w, w’ o(80%xSNAP) calibration/systematic uncertainties ?

34. R. PainEDEN, Dec 7 200534 SNLS vs DUNE vs SNAP

35. R. PainEDEN, Dec 7 200535 Summary SNe Ia are excellent distance indicators. Significant constraints on w require combining with constraints from other experiments (  M ) « 1st generation » SN experiments have reached their systematic limit 2nd generation projects are getting more and higher quality data. Toward building a Hubble diagram with ~1000 SN Ia Expected precision on (flat Univ., constant) w by 2008-9 : +/- 0.05 (stat) +/-0.05 (syst) Percent precision on w and significant precision on w’ (wa) with SN will require experiment in space.

36. R. PainEDEN, Dec 7 200536

37. R. PainEDEN, Dec 7 200537 3 bands: color compatibility (UBV rest frame)  U 3 = U(measured) – U(from B + V) SNe Ia UBV relations seems reproducible and redshift independent: - Redundancy of distances - small uncertainties in k- corrections  SNLS nearby Use (redundant) imaging to id SNe and control systematics ?

38. R. PainEDEN, Dec 7 200538 Images Spectra Redshift & spectral properties Light Curves dataanalysisphysics  M and   w and w’ SNAP concept Observables :

39. R. PainEDEN, Dec 7 200539 SNF (goal:300 SNe) SNLS (goal:700 SNe) DUNE (goal:10000 SNe) SNAP/Destiny (goal:2000 SNe) SNLS vs DUNE vs SNAP (simulation)