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Planck’ s constraints on the missing baryons (PIP-105)

Planck’ s constraints on the missing baryons (PIP-105). Carlos Hernández- Monteagudo Centro de Estudios de Física del Cosmos de Aragón (CEFCA), Teruel , Spain On behalf of the Planck collaboration. Outline. The kinetic Sunyaev-Zel’dovich effect ( kSZ )

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Planck’ s constraints on the missing baryons (PIP-105)

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  1. Planck’s constraints on the missing baryons(PIP-105) Carlos Hernández-Monteagudo Centro de Estudios de Física del Cosmos de Aragón (CEFCA), Teruel, Spain On behalf of the Planck collaboration

  2. Outline • The kinetic Sunyaev-Zel’dovich effect (kSZ) • The central galaxy catalogue (CGC) • Measuring the kSZ pairwise momentum • Correlating with a reconstruction of the peculiar velocity field • Constraints on the missing baryons Hernández-Monteagudo, "Planck's Constraints on the missing baryons"

  3. ThekineticSunyaev-Zel’dovicheffect • The kSZ effect expresses the Doppler kick experienced by CMB photons when scattering off rapidly moving electrons • The kSZ temperature anisotropies is independent of frequency (just like primary CMB anisotropies) • When looking at the direction of hot gas clouds, it is likely to be contaminated by the (dominant) thermal Sunyaev-Zel’dovich (tSZ) effect, which flips from negative to positive at the cross-over frequency of 217 GHz. • To avoid the tSZ and other contamination, we use different channels and foreground-cleaned maps, like SEVEM, SMICA and NILC. Hernández-Monteagudo, "Planck's Constraints on the missing baryons"

  4. The Central Galaxy Catalogue (CGC) • Based upon SDSS DR7 NYUAV galaxy catalogue after isolating brightest galaxies in 1 Mpc (transversal direction) and 1000 km/s (LOS) • It consists of 262 673 galaxies placed at z~0.12, of which ~83% should be true central galaxies. • When placing them in a grid, we retain only the 150,000 most nearby ones Fraction of brightestgalaxiesthat are actually central galaxies in theMilleniumsimulation (Guo et al. 2011, Planck PIP-XI) Hernández-Monteagudo, "Planck's Constraints on the missing baryons"

  5. MeasuringthekSZpairwisemomentum • ThepeculliarkSZparwisemomentum (pkSZ) isbuiltuponquantitiesevaluatedalongthe line of sight, • Itexpressesthegravitationalinfall/collapse of structure • Theestimates of thekSZtemperatureanisotropies are obtainedafterapplyingaperturephotometry (AP, TAP) ontheCGs, withvaryingaperture • Wesubtracttheaverage TAPwithin a thinredshiftshell of widthσz~0.01 (as in Hand et al. 2012, althoughresults do notdependcriticallyonthischoice) Hernández-Monteagudo, "Planck's Constraints on the missing baryons"

  6. MeasuringthekSZpairwisemomentum Wefound a colour-free decrementthatbecomes more significant (up to4 σ) forthecleaned SEVEM map and forapertures of 8 – 12 arcmin. For SEVEM @ 8 arcmin, a fittothe output of numericalsimulationsyieldsS/N ~ 4.5 Hernández-Monteagudo, "Planck's Constraints on the missing baryons"

  7. Error computation [1] [2]… Ncg … AP est.# [0][1] [2] [3]… [50] Werotate/displace theentire CGC overthe CMB mapswith no knownsources Hernández-Monteagudo, "Planck's Constraints on the missing baryons"

  8. MeasuringthekSZpairwisemomentum Hand et al. 2012 • Thebehaviour of thekSZsignalwrtapertureisdifferenttowhatisfound in simulatedclusters: thisconstitutesevidenceforsignaloutside halos. • Theimpact of tSZseemsto be negligible Simulatedclusters of Dolag & Sunyaev. 2013 Hernández-Monteagudo, "Planck's Constraints on the missing baryons"

  9. Invertinggalaxydensityintovelocity Weinvertthelinear continuityequationtoestimatethe peculiar velocityfieldfromthe CG densityfield Correlationcoefficient • Threeapproaches: LINEAR, LOG-LINEAR, LOG-2LPT • Impact of mask: LINEAR methodmostpromisingafterall Withoutmask Withmask Logarithmiclinearisation Hernández-Monteagudo, "Planck's Constraints on the missing baryons"

  10. Invertinggalaxydensityintovelocity <TkSZ . v/σv >: correlationbetweenkSZtemperatureanisotropies and recoveredvelocities (with RMS=1) • Linear reconstructionperformsbest, S/N ~ 4.6 • Wenormaliserecoveredvelocitiestounit RMS • Adoptingthevelocityamplitudeformthenumericalsims, we can infer a valueof τT(Thomson opticaldepth) Hernández-Monteagudo, "Planck's Constraints on the missing baryons"

  11. Consistencytests • We compute correlationaftershufflingtherecoveredvelocitiesamongtheCGs: thecorrelationisonlyrecoveredforthecorrectconfiguration • Thecoupling of intrinsicCMB largemodeswithlargespatialmodes of therecoveredvelocitiesconstitutesthelargestcontributiontothevariance: thelow-k modes of therecoveredvelocities are suppressedaftershufflingthese Hernández-Monteagudo, "Planck's Constraints on the missing baryons"

  12. Consistencytests χ2 Aperture [arcmin] As forthe peculiar kSZpairwisemomentum, wefind more kSZsignal at aperturescloseto 8 arcmin (~0.8 Mpc at z~0.12) than at 5 arcmin, and itextends up to ~12 arcmin. Thetypical CG virialradiusisbelow 200 Kpc: gas outside halos? Hernández-Monteagudo, "Planck's Constraints on the missing baryons"

  13. Measuringtheamoung of gas • Fromthe <TkSZ . v/σv > correlation, fromthe LINEAR approach, weobtain • τT= 1.7+0.6-1.0 x 10-4 • FromthekSZpairwisemomentum, weobtain • τT= 2.5 +/- 0.6 x 10-4 • For a typical CG halo weexpect • τT= 4x 10-5 Hernández-Monteagudo, "Planck's Constraints on the missing baryons"

  14. Implicationsforthemissingbaryons Leff = 105 Mpc Leff = 38 Mpc τT = σTneΔgLeff τT = 1.7+0.6-1.0 x 10-4 The Thomson opticaldepth (τT) isproportional/degeneratetotheproduct of density and length Leff = 0.8 Mpc Hernández-Monteagudo, "Planck's Constraints on the missing baryons"

  15. Implicationsforthemissingbaryons τT = 1.7+0.6-1.0 x 10-4 τT = σTneΔgLeff Leff = 2x0.8 Mpc (spheres) In thisplot, solidlinesprovidetheΔg(gas overdensity in volumesaroundCGs) requiredtoreachcosmicdensitylimitin allstructuresbelowdobs,max Leff = 38 Mpc (cylinders) Leff = 105 Mpc (cylinders) Hernández-Monteagudo, "Planck's Constraints on the missing baryons"

  16. Implicationsforthemissingbaryons τT = 1.7+0.6-1.0 x 10-4 τT = σTneΔgLeff Leff = 2x0.8 Mpc (spheres) In thisplot, solidlinesprovidetheΔg(gas overdensity in volumesaroundCGs) requiredtoreachcosmicdensitylimit in allstructuresbelowdobs,max Leff = 38 Mpc (cylinders) Leff = 105 Mpc (cylinders) CylinderscentreduponCGswithin d=300 Mpc/h occupy a volumefractionfvol= <nCGC> π rp2 Leffand contain a fraction of thecosmicbaryonbudgetfb: ≠ f(Leff) Hernández-Monteagudo, "Planck's Constraints on the missing baryons"

  17. Implicationsforthemissingbaryons τT = 1.7+0.6-1.0 x 10-4 Leff = 2x0.8 Mpc (spheres) AccordingtoPlanck, cylinderscentreduponCGs up to a distance d=300 Mpc/h contain a fraction of 80+30-50 % of allbaryons. Thatis, Planck’sobservations are compatible tohavingdetectedallmissingbaryonsat z~ 0.12 Leff = 38 Mpc (cylinders) Leff = 105 Mpc (cylinders) Hernández-Monteagudo, "Planck's Constraints on the missing baryons"

  18. Conclusions • Planck has measured a pairwisemomentum in thedirection of central galaxies (CGs) at z=0.12 thatisindependent of frequency and shows a formveryclosetoexpectationsfromnumericalsimulations and previousmeasurements of Hand et al. 2012. Thesignficancelevelforfrequencymapslies at thelevel of 3σ, increasingto > 4σ forforeground-cleanedmaps. • Thevalue of the Thomson opticaldepthfromthispairwisemomentumis • τT= 2.5 +/- 0.6 x 10-4 • Afterinvertingthe CG densityfieldintoanestimate of the peculiar velocityfield, and cross-correlatingittoPlanck kSZtemperatureestimates, wefindevidenceforbulkflowsextending up to~ 100 Mpc/h withS/N> 4.5. Theinferredvalueforthe Thomson opticaldepthis • τT= 1.7+0.6-1.0 x 10-4 • In both cases, wefindevidenceforkSZsignalarisingoutside halos. Accountingforthe CG numberdensity, wefindthatstructurescontributingtothekSZaroundallCGs up to 300 Mpc/h contain80+30-50 % of allbaryons. Hernández-Monteagudo, "Planck's Constraints on the missing baryons"

  19. The scientific results that we present today are a product of the Planck Collaboration, including individuals from more than 100 scientific institutes in Europe, the USA and Canada Planck is a project of the European Space Agency, with instruments provided by two scientific Consortia funded by ESA member states (in particular the lead countries: France and Italy) with contributions from NASA (USA), and telescope reflectors provided in a collaboration between ESA and a scientific Consortium led and funded by Denmark. Hernández-Monteagudo, "Planck's Constraints on the missing baryons"

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