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Square Kilometre Array » SKA PtiPerspectives of soltilution: ftfuture instruments Euclid Françoise Combes E-ELT The great In construction obtibservatories of the future ALMA inaugurated in 2013 Atacama desert ALMA In operation JWST 2018 2 Large field of view and billions of galaxies Construction 2018-22 Euclid, 2020 1 billion $ 3 BAO: baryonic oscillations Standard ruler Test Can also test the bias b Or = 0.6/b cz/H m Observer Eisenstein et al. (2005) D 50 000 galaxies SDSS cz/H = D determine H(z) Recent BAO results with spectro-z Excellent agreement with CDM (grey) DV (z=2.34) = 4628 Mpc Slosar et al 2013 Delubac et al 2014 Anderson et al 2012 5 BAO in the Ly forest at z=2.3 137 000 BOSS quasars (cos 212.1 < z < 353.5 Blue Ly autocorrelation Red: Quasar-Ly cross-correl (Font-Ribera et al 2013) Black: combined Delubac et al 2015 Red points : obs compared with simulations of quasars(grey) rd sound horizon DA angular dist, DH= c /H TiTension with Planc kà25k à 2.5 6 RSD « Redshift space distortions » Dis tor tions due to peculiar velocities on the line of sight (Fingers of God) Kaiser effect in clusters Systematic infall These velocity flows allow to determine 0.6 = m /b bias δgalaxies = b (δmass) and gal 7 Status of RSD measures tt of sigh ee Various galaxy surveys VIPERS, de la Torre et al 2013 n the lin oo f (growth rate) ration 8 aa Separation on the sky Sep Thick line: GR gravity Dahed or dotted lines Mo difie d grav ity DGP (Dvali et al 2010 f(R) models, etc.. z 8 Tension on H0 between Planck, Cepheids, BAO … BAO at 68 and 95% confidence level (blue) Ho (Cepheids) = 74km/s/Mpc, while Planck favors 67 km/s/Mpc Planck Delubac et al 2014 9 Growth rate as a test of gravity Growth rate f= dlog () /dlog (a) ~m This growth produces peculiar velocities RSD The growth rate will be measured by 1- Weak Lensing (WL) Tomography 2- Redshift-space distortion in galaxy clusters (RSD) 10 «Square Kilometre Array » Project (~2020 -30) for a giant radiotelescope in the centimetre-metre range • one square kilometre collecting surface 50-100 x more sensitive than present radio telescopes for spectral line observations 1000 x more sensiti ve than present radio tltelescopes for continuum observations • frequencies: 70MHz – 25 GHz ( 1.2cm – 4m) • field of view: 1 ( 100?) square degrees at 21 cm / 1.4 GHz 8 independent fields of view • angular resolution: 0.01 arcsec at 21 cm / 1.4 GHz baselines up to ~ 3000 km In Australia and in South Africa 11 Multi-beam observation EMBRACE Prototype at Nancay SKA: Square km Array Surface: one million m2 World wide project in m/cm will observe HI-21cm redshifted from galaxies up to z=5 (itdinstead of03f z=0.3 tdtoday) Follow the DM content of galaxies In all the history of the Universe 13 HI mass detectable as a function of z in 360 h z Time Mass HI # Detections HI mass function (Gyr) (Mo) 0.5‐1.0 4.2‐6.2 1.7 108 6.6 105 1.0‐1.5 6.2‐7.3 4.7 108 2.3 105 1.5‐2.0 7.3‐8.0 1.1 109 1.0 105 2.0‐2.5 8.0‐8.5 2.2 109 4.4 104 2.5‐3.0 8.5‐8.9 4.1 109 3.0 104 303.0‐353.5 898.9‐919.1 676.7 109 101.0 104 3.5‐4.0 9.1‐9.2 1.2 1010 9.5 103 4.0‐4.5 9.2 9.3 1.6 1010 7.0 103 Star Formation vs z 14 Maximum redshift pour une intégration de 360 h avec SKA 2000 gggalaxies/ deg M 101 100 000 Rotation curves As a function of time 30 000 M 51 SMC 15 Search of dark dwarfs in HI ALFALFA: Arecibo (300m) Red: optical Blue HI ShSearch ithin the voids: Green: both Negative until now 16 ALFALFA: High velocity HI clouds Search of stars in optical: Always a signal found Discovery of normal dwarfs No dark dwarfs 6 M(HI) ~ 10 M 17 Haynes 2008 Always some stars, low 7.2 Images SDSS M(HI) < 10 M 18 Haynes 2008 Discovery of 2 candidates? 0.4% of systems Almost dkdark Janowiecki et al 2015 19 Kinematics of HI clouds Just outside of the Virgo cluster One of the systems is composed of 2 clumps Is the DV between them relevant? Difficult to identify any rotation, or interpret the velocity profiles Inclination? May be face-on 20 Baryy(on Fraction (stars) Halo abdbundance matching And for 8000 selected galaxies Papastergis et al 2012 21 Baryy(on Fraction (stars+gas) reio fraction of baryons predicted by hydrodynamical simulations Including the reionization Okamoto et al 2008 Baldry + 2008 Thickness of the line: sensitivity HI gas Papastergis et al 2012 22 EUCLID satellite 1-What is dark energy: w P= w Equation of state and nature of DE, through expansion and growth rates, 5 tools: Weak Lensing, BAO, RSD, Clusters, ISW 2-Gravity beyond Einstein: Testing modified gravity, by measuring growth rate exponent 3-The nature of dark matter, m Testing the CDM theory, and measuring neutrino mass 4- The seeds of cosmic structures Improve by a factor 20, n= spectral index, 8=amplitud e of power spect rum, fNL= non-gaussianities 23 Mass and number of neutrinos With extra mass-less neutrinos with one sterile massive neutrino -- thermal mass Planck coll (2013) Paper XVI Neutrino mass constraint from power-spectrum (free-streaming) Neff could be higher due to lepton asymmetry or the existence of a sterile neutrino With Euclid (M ) = 0.03 eV, (N ) = 0.02 eff 24 Predictions with Euclid Deviations to the GR 50 millions of galaxy z f = dlog/dloga, Coupled CDE c=0.2 where (t) is the growth factor GR 8 variance : amplitude of structures Flat DGP model (normalisation) f8 measured by the anisotr opy RSD Majerotto et al 2012 (GR) = 0.55 CDE, DGP, di Porto et al 2012 25 f(z) ~m Exploration of dark energy models with Euclid (redhiftdshiftsonlly withou t WL) 26 EUCLID Legacy Wide survey 15 000 deg2 Deep survey 40 deg2 (+2mag) 12 billion sources (3) 50 million redshifts A reservoir of targets for JWST,,,GAIA, ELT ALMA, Subaru, VLT, etc … 27 Strong Lensing: 60 SLACS 28 Will become an industry Study of sub-structures Constraints on dark matter Similar number per unit surface then SKA 100 000 29 Cold or Warm dark matter? CDM WDM 30 Maaeke images withlenses CLASS B2045+265, VLA 15GHz NIR, Keck Dwarf G2: lens E=G1 Detect sub-structures as anomalous flux ratios between images sbsub-struct ures seen as brightness anomalies Until now: only bright dwarfs found No need of dark halos Sub-structure: source or lens? 31 The tool of strong lensing B1938+666 Radio (Merlin) HST NIR Potential EVN smooth + (pixel) 3mas McKean Model the sub-structures both in the source and in the lens 32 Simple model of smooth source ~r Data Model SDSSJ120602. 09+ 514229. 5 Vegetti et al 2010 Résidual Source 33 Addition of a sub-structure Smooth Potential M = 107 M sub 34 Vegetti et al 2009 Addition of a sub-structure (2) Smooth Potential M = 108 M sub 35 Vegetti et al 2009 Degeneracy source-lens Smooth Potential 9 Msub =10= 10 M 7 Possible to detect M> 10 M on the Einstein ring, or 9 M> 10 M close to the ring 36 Vegetti et al 2009 Present Constraints, 12 Einstein rings No « dark » structure detected, The smallest M detectable, One bright sub-structure detected 10 <z>=0.2, <> = 270km/s unit 10 M f CDM pente de la fonction de masse SDSS J0252+0039, Vegetti et al 2014 f< 0.006 mass fraction in the sub-structures < 1.90 37 CASTLES Near IR 38 Einstein rings in optical 39 Einstein rings in radio The first detection was in radio! 50 years after the prediction of Einstein MG1654+1346 Langston 1988 MG1131+0456,,,y Hewitt 87 PKS1830, Jauncey 1991 40 B0218, Merlin Biggs et al 2001 Other data: time delay Lens+ kinematics +delay Curvature k Ho, w (dark nergy) P= -w k k Ho Ho For a flat universe, Ho= 82km/s/Mpc Et w= -151.5 w w Ho = 65km/s/Mpc, if open universe RXJ1131−1231, Suyu et al 2014 H o Ho 41 Observations of lenses with ALMA Grey: near-IR images with HST, VLT, SOAR Vieira et al 20 13 ( 23/ 26 detected) 10 sources z > 4 Red=870 m contours ALMA, 2min, 0.5’’ Redshift spectro obtained with ALMA Cycle 0 (16 antennae instead of 60) 42 Statistical constraints with ALMA 8 An individual halo is detectable only if M> 10 M, but 6 Statistical constraint on a multitude of halos M~10 M Dalal & Kochanek 2002, Hezaveh et al 2015 Power spectrum of residuals The power o f the lens depends on the mass concentration Point sources = cste Green curve: the slope of the mass function is changed by 050.5 dn/dM ∝ M− Hezaveh et al 2015 43 Perspectives: strong lensing Square Kilometre A(Array (SKA), ALMA Large Synoptic Survey Telescope (LSST) Euclid + telescopes to follow on the ground with high -fidelity, Number of lenses >> 104 200 lenses of excellent quality 8 Sub-structures M> 10 M, The ftifraction ofDMif DM in the su b-struct ures will b e contrained to f < 0.005+0.001 (lower than CDM predictions) Anomalies in the flux ratio between images, kinematics Also method of time delays between images (variable QSO) 44 The bullet cluster Gas X Rare cas of violent collision, allowing Masse totale to separate components 2 V=4700km/s (Mach 3) Limit on DM/mDM < 1 cm /g For modified gravity, need of non-collisi onnal matter: neutrinos or dark baryons Abell 520 z=0.201 Red = gas X Contours = lenses Dark matter coïncides with the gas X bu t void of galaxies 2 Collisions DM/mDM~ 4cm /g Or else existence of galaxies in 3? Mahdavi et al 2007, Clowe et al 2012 Jee et al 2012, Jee et al 2014 Blue Dark matter Red=X Controversy: A520, z=0.199 The total mass derivation made with different maps Mahdavi+07: central peak of DM Okabe & Umetsu 08: itin agreement with Mahdavi+07; Jee+12; 14 But not Clowe+12.
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