Status of CMB & the promise of an Indian collaborative space mission
Astro-Particle Physics meet Tarun Souradeep IUCAA, Pune CGPA-IFTHEP@ IISER Pune On behalf of CMB-Bharat Feb. 25, 2018 (Indian CMB consortium) Cosmic “Super–IMAX” theater
COBE – 0.5 Myr FIRAS
Here & Now (14 Gyr)
Transparent universe
Opaque universe CMB Anisotropy & Polarization
CMB temperature
Tcmb = 2.725 K
-200 K < T < 200 K
Trms ~ 70 K
TpE ~ 5 K TpB ~ 10-100 nK
Temperature anisotropy T + two polarization TT modes E&B Four CMB spectra : Cl , EE BB TE Cl ,Cl ,Cl
TB EB Parity violation/sys. issues: Cl ,Cl CMB anisotropy measurements 1st, 2nd and into the 3rd decade
1991-94
2001-2010
FIRS, Tenerife CAT, VSA, … 2009-2011
Boomerang, MAXIMA, BICEP 1&2,KECK Archeops, DASI, CBI, POLARBEAR, ACBAR, QUAD.,,, SPT, ACT SPIDER, .. CMBPol/COrE 2020+ 0' * 47"%&' ( )' .)01 2)* 74)."' * )5?"##) &75#++%5#)* %&&%' ( &)
- CF0GH$. /012342567$I #$3) /1$9/: /;$5 * + , - $. /012342567$8#$3) /1$9/: /;$5 ?@$ * + , - $A/1BCD3B07$EE$3) /1$9/: /;$5 ?@$ ! +7( $8)%&).7")&94#"%' ")5?7( )4"#A%' 9&)5L ' )&75#++%5#)%( )5#"* &)' .)7( , 9+7") "#&' +9I ' ( )7( / )&#( &%I A%5- )) Courtesy: Soumen Basak CMB Temperature at Planck Frequencies Credit: ESA, HFI & LFI consortia CMB Polarization at Planck Frequencies Credit: ESA, HFI & LFI consortia Foreground for CMB anisotropy Foreground for CMB Polarization Cleaning the background from its 7 veils Page 24 François R. Bouchet "Planck main cosmological results" 3% of the CMB sky replaced by a Gaussian Random realisation Planck CMB sky map Truly all-sky !!! Only 3% of sky replaced by constrained realization Planck Collaboration: The Planck mission AP CMB Foregrounds : Rich A&A science d 0 20 200 µKRJ @353 GHz p Fig. 21. Dust polarization amplitude map, P = Q2 + U2, at 353 GHz, smoothed to an angular resolution of 100, produced by the di↵use component separation process described in (Planck Collaboration X 2015) using Planck and WMAP data. Fig. 22. All-sky view of the magnetic field and total intensity of dust emission measured by Planck. The colours represent intensity. The “drapery” pattern, produced using the line integral convolution (LIC, Cabral & Leedom 1993), indicates the orientation of magnetic field projected on the plane of the sky, orthogonal to the observed polarization. Where the field varies significantly along the line of sight, the orientation pattern isirregular and difficult to interpret. 29 Fermi Planck multiple synergies Planck, Fermi, L & the “dark” gas AT > 10 G old radio eV gas & loops dust in clouds bubbles & haze SNRs blazars ck Isabelle Grenier Plan interstellar AIM, Paris Diderot & CEA Saclay radiation field on behalf of both collaborations SZ clusters from Planck Planck sky maps Statistics of CMB CMB Anisotropy Sky map => Spherical Harmonic decomposition l T ( ,) almYlm( ,) l2 ml * alm a l'''' m C l ll mm Gaussian Random field => Completely specified by angular power spectrum Dl = l(l+1)Cl : Dl : Power in fluctuations on angular scales of ~ /l radians Planck Angular power spectrum 2015 Planck CMB Polarization spectra EE: 2015 Planck CMB Polarization spectra TE Acoustic physics CMB Angular power spectrum 150 Mpc. (fig credit: W. Hu) CMB physics is very well understood & accurately computed CMB@IUCAA: CMBAns Boltzmann code by Santanu Das Multi-D Joint Posterior distribution P( parameters |Cl ) 2 Baryons: Ωbh 2 Cold Dark Matter: Ωmh Hubble constant : H0 Reionization Depth : t Primordial fluctuations – Spectral index: ns Amplitude: As Standard 6 parameter flat, LCDM model (S Das & TS : JCAP 2014) Cosmological Parameters 6-Parameter LCDM 1% 1.7% 0.04% 0.6% ’Standard’ cosmological model:1.3% Flat, LCDM with nearly Power Law (PL) primordial power spectrum 1.4% Paradigm of Hot & Dense early Universe i.e., ‘Big Bang’ model Cosmic “Super–IMAX” theater 0.5 Mega-years Here & Now (14 Giga-years) TransparentUniverse universe must have been at least (107x) hotter & 1021 x denser in its past Opaque universe COBE-FIRAS results strongly constrain any Energy input into the CMB in the not-so-early universe (z<105) 60 Ghz 600 Ghz E 2.5104 , E ( 500 5000m) Spectral distortions expected at ~10-8 level carry important cosmological information on its thermal history. A new emergent observational thrust area of CMB research ARCADE 2004 10 Ghz 30Ghz (figs: Bond, 1996) Paradigm of CMB flucs: Acoustic phenomena pre-recombination Plasma universe Paradigm of Structure formation? - Backbone of `precision’ cosmology Gravitational Instability Mildly Perturbed universe Present universe at z=0 at z=1100 Cosmic matter content tot b DM L H 0 Weak lensing: Light deflects due to gravity Projected LensingPlanck Collaboration: potentialThe Planck mission from Planck Planck Collaboration: Gra0vitational1 2lensing)Kby#lar(ge-scale&%(structures, )withPlanck Planckat theexpectedlevel. InSect. 3.3, we cross-correlatethe reconstructedlensingpotential withthelarge-angletemperature T⇥ anisotropiestomeasuretheCL correlationsourcedby theISW effect.Finally,thepowerspectrumof thelensingpotential ispre- sentedinSect. 3.4. Weusetheassociatedlikelihoodalone, and in combination with that constructed from the Planck temper- atureand polarization power spectra (Planck Collaboration XI 2015), toconstraincosmologicalPlanck Collaboration:parametersGra0vitational1inSect.2lensing3.5)K. by#lar(ge-scale&%(structures, )withPlanck Planckat theexpectedlevel. InSect. 3.3, we cross-correlatethe 3.1. Lensing potential reconstructedlensingpotential withthelarge-angletemperature 1 T⇥ ⇥ˆWF (Data) anisotropiesInFig.to2measurewe plotthetheCWL ienercorrelation-filteredsourcedminimumby the-varianceISW lensing effect.Finallyestimate,,the0gipo1venwer2)by+#spectrum( &%( , 6of) thelensingpotential ispre- sentedinSect. 3.4. W⇤−eusetheassociated−⇤ likelihoodalone, and Fig.2 Lensingpotential estimatedfromtheSMICAfull-mission d (ˆn) = ⇧ ⇤(ˆn⇥)⇥, fid K' L )* 7&&)/ #( &%5- ) in combination with• rthat#*constructed74&)5?#)Cfrom01 2the)k#Planc+/ )Lk%temper5?' 95-) CMBJ %,maps?)* 7&using&)/ #(the&%5-MV) estimator1 7&8) . The power spectrum of ⇥ˆWF = L ⇥ˆMV, (5) thismapformsthebasisof our lensinglikelihood. Theestimate atureand polarization$?po7wer( ,LM%spectra( , )&9⇥⇥"(,Planck.fid7$#)HCollaboration⇥"⇥%, LM?5( #&&)XI 2015), toconstraincosmological parametersCL + NinLSect. 3.5.⇥ hasbeenWiener filteredfollowingEq. (5), andband-limited to −⇤ • 1 #7&9"#*1#( 5)' .)?%, ?#")' "/ #")( ' ( R ⇥⇥, fid∆T(nˆ) −⇤ ∆T ˆn + d (ˆn) 8≤ L ≤ 2048. whereCL isthelensingpotential powerspectruminour fidu- V79&&%7( )$' ""#+7I ' ( )?#+4&)5' )"#$' ( &5"9$5) 3.1. Lensingcial modelpotential) and−⇤N⇥⇥ isthe−⇤noisepower spectrum of therecon- L ⌥ +#(1 &%( , )&%, ( 7+=)L ?%$?)%&)"#+75#/ )5' )5' 57+) d (ˆn) = ⇧ ⇤(ˆn) K#( &%( , )4' 5#( I 7+) ⇥ˆWF (Data) InFig.struction.2we plot)theAsWweienershall-filtereddiscussmminimum⇥inSect.-v4.5ariance, thelensinglensingpotential estimateisunstable⌅ h2 =for L < 8, and so we haveexcluded those * 7&&)7+' ( , )5?#)+%( #)' .)&%, ?5))) estimate,0gi1ven2−⇤)by+#( &%( ⇥, 6) modesFig.for11.)))all)W))>analysesiener- 4−⇤%-filtered$7+)inr941thislensing:eVpaper)A7+9,potential#as)'well.)/ 6as)estimates)inQ`⇥the] )7MV"with$*Fig.lensing%minimal( ))2 Lensingmaskingpotential(usingestimatedthe NILCfromcomponenttheSMICAseparatedfull-missionmap), in Galactic d (ˆn) = ⇧ ⇤(ˆn⇥)⇥, fid −⇤ 1 7&8) K' L )* 7&&)/ #( &%5- ) map.• coordinatesr #* 74&with)5?#a)CMoll01 2weide)k#+/projection)L %5?' 9(5Planck) CollaborationCMBJ %,maps?XV)* 72015&using&)/ #).(the&The%5-MV)reconstructionestimator. Thehasbeenpowerbandlimitedspectrum toof 8 L 2048 (where,• ⇥folloˆWF;∆( =wing/T(9$nˆ#)con&L−)$v⇤'ention,⇧""∆#⇥T+ˆ7MVLI ,is'ˆn (used+⇤)Hd#⌅as5L(ˆ⌃then#)#multipole( (5))01 2this)indekmap#+x/in)formsthe lensingthebasispoofwerourspectrum).lensinglikelihood. Theestimate As$a?visual7( ,LM%(illustration, )&9⇥⇥",.fid7$#of)H⇥the"⇥%, signal-to-noiseLM?5( #&&⇤) level inthelens- CL +4NL ⇥ hasbeenWiener filteredfollowingEq. (5), andband-limited to ingpotential estimate,'V(()⇤5?)=#)&in⇥8Fig.- )71+(3/−⇤we)%c5o&plots), "7a/simulation%#( 5=)?#(of$the#•= )MV1 #7&9"#*1#( 5)' .)?%, ?#")' "/ #")( ' ( R ⌥ f 8≤ L ≤ 2048. reconstruction,⇥⇥, fid∆T(nˆ)+#−as7⇤Awell#∆&)7Tas)/ %ˆnthe&I+(input$d5)(ˆ(n⇥')(realizationRV79&&%7used.( ) There- whereCL logicalisthemodelslensing2analysedpotential pominwer⇥thespectrum2015 Plancinourk papers.fidu- HoweVver7,9&&Compact%7( )$' "sources"#+7I 'are( )detected?#+4&)5in' )the"#$single-frequenc' ( &5"9$5) y maps and construction) in this ⇥data⇥ and&⌅%release,,⇥input(h75=9are"we#)clearly're⇤(g)ard01correlated,the2`⌅)combined) although⌅ TT, TEthe, recon-and EE assigned to one of two sub-catalogues, the PCCS2 or PCCS2E. cial model and−⇤NL isthe−⇤noisepower spectrum2of⇤therecon- +#( &%( , )&%, ( 7+=)L ?%$?)%&)"#+75#/ )5' )5' 57+) structiond has(ˆn)considerable=⌥⇧ ⇤(ˆn)94additionaleV −power3 due tonoise. Ascan )F;%247! #&I "&! #N! $$ struction.)AsPlancwekshallresultsdiscussasmpreliminaryinSect.4 4.5. ,Kthe#( &lensing%( ,M)4pl'potential5#( I 7+) The first of these allows the user to produce additional sub- 2 V(⇤)=⇥ ⇥ 1− e ˆWF estimatebeisseenunstable⌅ ⇥inhFig.=for1L, e 4 Projected Lensing power spectrum Planck Collaboration: The Planck mission 2 Planck (2015) SPT ] ACT 7 Planck (2013) 0 1.5 1 × Matches expectations but [ π Huge room for improvement 2 1 / from measuring the (Lensing of) φ φ L CMB polarization information C 2 ] ) 0.5 1 + L ( 0 L [ − 0.5 1 10 100 500 1000 2000 L Fig. 18. Lensing potential power spectrum estimate from the2015 datarelease (Planck Collaboration XV 2015), based on theSMICA CMB map, as well as previous reconstructions from Planck as well as other experiments for comparison. all-sky maps of polarized intensity, P, polarization fraction, p, 11.2.2. The Galactic magnetic field and polarization angle, , presented in Planck Collaboration X (2015) is illustrated in Fig. 22. Here we summarize the main The Planck maps of p and contain information on the mag- results from the data analysis by the Planck Consortium. The re- netic field structure. The data have been compared to syn- lease of the data to the science community at large will trigger thetic polarized emission maps computed from simulations of many more studies. anisotropic magnetohydrodynamical turbulence, assuming sim- ply a uniform intrinsic polarization fraction of dust grains (Planck Collaboration Int. XX 2014). The turbulent structure of 11.2.1. The dust polarization sky the magnetic field isable to reproduce the main statistical prop- Planck Collaboration Int. XIX (2014) presents an overview of erties of p and that are observed directly in avariety of nearby the polarized sky as seen by Planck at 353 GHz, the most sensi- clouds (dense cores excluded). The large-scale field orientation tive Planck channel for polarized thermal dust emission, focus- with respect to the line of sight plays a major role in the quanti- 22 −2 tative analysis of these statistical properties. This study suggests ing on the statistics of p and . At all NH below 10 cm , p 22 −2 displays a large scatter. The maximum p, observed in regions of that the large scatter of p at NH smaller than about 10 cm is moderatehydrogen column density (N < 2⇥1021 cm−2), ishigh due mainly to fluctuations inthemagnetic field orientation along H the line of sight, rather than to changes in grain shape and/or the (pmax ⇡ 20 %). There isa general decrease in p with increasing 21 −2 efficiency of grain alignment. column density above NH ⇡ 1 ⇥10 cm and in particular a 22 −2 sharp drop above NH ⇡ 10 cm . The formation of density structures in the interstellar The spatial structure of is characterized using the angle medium involves turbulence, gas cooling, magnetic fields, and dispersion function S, the local dispersion of introduced by gravity. Polarization of thermal dust emission is well suited Hildebrand et al. (2009). Thepolarization fraction isfound to be to studying the role of the magnetic field, because it images anti-correlated with S. The polarization angle is ordered over structure through an emission process that traces the mass of extended areas of several square degrees. The ordered areas interstellar matter (Planck Collaboration XI 2014). The Planck are separated by long, narrow structures of high S that high- I map shows elongated structures (filaments or ridges) that light interfaces where the sky polarization changes abruptly. have counterparts in either the Stokes Q or U map, or in These structures have no clear counterpart in the map of the both, depending on the mean orientation. The correlation be- total intensity, I. They bear a morphological resemblance to tween Stokes maps characterizes the relative orientation be- features detected in gradient maps of radio polarized emission tween the ridges and the magnetic field. In the di↵use in- (Iacobelli et al. 2014). terstellar medium, the ridges are preferentially aligned with 27 Paradigm of Inflation in the Early Universe ? -necessary to seed structure Who pinged the Cosmic drum ? Early Universe The Cosmic screen Present Universe Early Universe in CMB The Background universe Homogeneous & isotropic space: Cosmological principle Flat (Euclidean) Geometry The nature of initial/primordial perturbations Power spectrum : ‘Nearly’ Scale invariant /scale free form Spin characteristics: (Scalar) Density perturbations Type of scalar perturbation: Adiabatic -- no entropy fluctuations Underlying statistics: Gaussian Status of Inflationary models Talk by L. Sriramkumar IIT Madras Level of Non-Gaussian signature probed is a very subtle !!! Fig. credit: kicphubs.uchicago.edu Early Universe in CMB The Background universe Homogeneous & isotropic space: Cosmological principle Flat (Euclidean) Geometry The nature of initial/primordial perturbations Power spectrum : ‘Nearly’ Scale invariant /scale free form Spin characteristics: (Scalar) Density perturbations … cosmic (Tensor) Gravity waves !?! Type of scalar perturbation: Adiabatic -- no entropy fluctuations Underlying statistics: Gaussian Planck Collaboration: Constraints on inflation 11 −δ with Alow = As(kb/ k⇤) to ensure continuity at k = kb. Hence 4 Planck 2013 0 this model, like the previous one, has two parameters, and also . 0 suppresses power at large wavelengths when δ > 0. We assume k Planck TT+ lowP n −1 l top-hat priors on δ 2 [0, 2] and ln(kb/ Mpc ) 2 [−12 , −3], and d Planck TT,TE,EE+ lowP / 10 s standard uniform priors for ln(10 As) and ns. The best fit to n d Planck TT+lowP (Planck TT,TE,EE+lowP) is found for ns = x −1 e 0.9658 (0.9647), δ = 1.14 (1.14), and ln(kb/ Mpc ) = −7.55 d n 0 2 2 i 0 l (−7.57), with a very small χ improvement of ∆χ ⇡ −1.9 . a 0 CORE mission r (−1.6). t c e Weconclude that neither of these two models with two extra p s parameters is preferred over the base ⇤CDM model. (See also g n i the discussion of a step inflationary potential in Sect. 9.1.1.) n n u Cosmic GW background 4 R 0 . 0 5. ConstraintsFromon Inflationtensor modes − Inthissection, wefocuson thePlanck 2015 constraints on tensor 0.92 0.94 0.96 0.98 1.00 Eachperturbations. polarizationUnless ofotherwise Gravitonstated, behaveswe consider likethat athe ten- ns Massless,sor spectral Minimallyindex satisfies coupledthe standard scalarinflationary field consistency condition to lowest order inslow-roll, nt = −r/ 8. Werecall that r Fig. 5. Marginalized joint confidence contours for (akin to fluctuations of inflaton) −1 isdefined at thepivot scale k⇤= 0.05 Mpc . However, for com- (ns , dns/ dlnk), at the 68 % and 95 % CL, in the presence To/Mustparison with -otherDostudies, for cosmologywe also report our bounds!!!! in terms of of anon-zero tensor contribution, and using Planck TT+lowP or −1 Generationthe tensor-to-scalar of ratioscalarr0.002 perturbationsat k⇤= 0.002 Mpc is . Planck TT,TE,EE+lowP. Constraints from the Planck 2013 data accompanied by generation of Inflationary GW release are also shown for comparison. The thin black stripe shows the prediction of single-field monomial inflation models 5.1. Planck 2015 upper bound on r Ratio of GW/Density perturbation: with 50 < N⇤< 60. Ther ~constraints Energyon thescaletensor -to-scalarof inflationratio infered from the Planck full mission data for the ⇤CDM+r model are: with the Planck 2013 results. The mean value of the running in Eq. (28) is higher (lower in absolute value) than with Planck r0.002 < 0.10 (95% CL, Planck TT+lowP) , (22) 2013 by 45 %. Figures 5 and 6 clearly illustrate this significant r0.002 < 0.11 (95% CL, Planck TT+lowP+lensing) , (23) improvement with respect to the previous Planck data release. r0.002 < 0.11 (95% CL, Planck TT+lowP+BAO) , (24) Table 4 shows how bounds on (r, ns, dns/ d lnk) are af fected by r0.002 < 0.10 (95% CL, Planck TT,TE,EE+lowP) . (25) thelensing reconstruction, BAO, or high-` polarization data. The tightest bounds are obtained in combination with polarization: Table 4 also shows the bounds on ns in each of these cases. These results slightly improve over the constraint r0.002 < r0.002 < 0.15 0.12 (95% CL) derived from the Planck 2013 temperature (95% CL, Planck TT,TE,EE+lowP), (29) data in combination with 18WMAP large-scale polarization data dn s = −0.009 ± 0.008 (Planck Collaboration XVI, 2014; Planck Collaboration XXII, d lnk 2014). The constraint obtained by Planck temperature and po- (68% CL, Planck TT,TE,EE+lowP), (30) larization on large scales istighter than Planck B-mode95 % CL upper limit from the 100 and 143 GHz HFI channels, r < 0.27 with ns = 0.9644 ± 0.0049 (68% CL). (Planck Collaboration XI, 2015). Theconstraints on r reported in Neither thePlanck full mission constraints inEqs. (22)–(25), Table 4 can be translated into upper bounds on the energy scale nor those including a running in Eqs. (27) and (29), are com- of inflation at the time when the pivot scale exits the Hubble patible with the interpretation of the BICEP2 B-mode polariza- radius, using tion data in terms of primordial gravitational waves (BICEP2 Collaboration, 2014b). Instead, they are in excellent agree- 3⇡2A r ment with the results of the BICEP2/Keck Array-Planck cross- V = s rM4 = (1.88 ⇥1016 GeV)4 . (26) ⇤ 2 pl 0.10 correlation analysis, as discussed in Sect. 13. This gives an upper bound on the Hubble parameter during in- −5 flation of H⇤/ Mpl < 3.6 ⇥10 (95% CL) for Planck TT+lowP. 5.2. Dependence of the r constraints on the low-` These bounds are relaxed when allowing for a scale depen- likelihood dence of the scalar and tensor spectral indices. In that case, we The constraints on r discussed above are further tightened by assume that thetensor spectral index and itsrunning arefixed by adding WMAP polarization information on large angular scales. the standard inflationary consistency condition at second order The Planck measurement of CMB polarization on large angular in slow-roll. We obtain scalesat 70 GHz isconsistent with theWMAP9-year one, based on the K, Q, and V bands (at 30, 40, and 60 GHz, respectively), r0.002 < 0.18 (95% CL, Planck TT+lowP), (27) once the Planck 353 GHz channel is used to remove the dust dns +0.010 = −0.013−0.009 (68% CL, Planck TT+lowP), (28) contamination, instead of the theoretical dust model used by the d lnk WMAP team (Page et al., 2007). (For a detailed dicussion, see with ns = 0.9667 ± 0.0066 (68% CL). At the standard pivot Planck Collaboration XI (2015).) By combining Planck TT data −1 scale, k⇤ = 0.05 Mpc , the bound isstronger (r < 0.17 at 95% with LFI 70 GHz and WMAP polarization data on large angular CL), because k⇤iscloser to the scale at which ns and r decorre- scales, we obtain a 35 % reduction of uncertainty, giving ⌧= late. Theconstraint on r0.002 inEq. (27) is21 % tighter compared 0.074 ± 0.012 (68% CL) and ns = 0.9660 ± 0.060 (68% CL) Planck Surveyor Satellite European Space Agency: Launched May 14, 2009 HFI completed Jan 2012 Planck Satellite on display at Cannes, France (Feb. 1, 2007) Next CMB space mission: Why ? • Cosmic Microwave Background (CMB) measurements have been transformational for Cosmology • Planck mission (ESA) extracted ≈100% of CMB temperature information (> 1000 × information compared to COBE 1994, > 10 × WMAP ) But extracted only a small fraction (10%) of the rich CMB polarisation information available (and much less for specific measures) And, no significant addition on CMB spectral information since COBE Scientific promise •Reveal signature of quantum gravity and ultra-HEP in the very early universe •Improve probe of cosmological model by a factor of > 10 million •Map all dark matter and most baryons in the observable universe •Unique probe of the ‘entire’ thermal history of the universe Planck Focal Plane Complex systematics and tough analysis Credit: ESA, HFI & LFI consortia CMB ‘next’ Focal Plane GHz Ndet 60 24×2 70 24×2 80 24×2 90 39×2 100 39×2 115 38×2 130 124 145 144 160 144 Design challenge: scan 175 160 systematics and analysis !!!! 195 192 220 192 255 128 295 128 340 128 390 96 450 96 520 96 600 96 D=50 cm TOTAL 2100 Coolest Satellite in Space! H2 Sorption cooler - LFI FPU to < 20K - pre-cool lower stages 4He J-T cooler - HFI FPU and LFI reference loads to < 5K Dilution cooler - HFI bolometers to 0.1K Cryogenic Cooling chain S S Strawman concept : CORE (ESA-M5) CORE-M5 primary design driver: CMB polarisation CORE-M5 Main ≈ 4.0 4.0 ≈ m characteristics: -Total wet mass ≈ 2.0 tons -Diameter ≈ 4.4 meter -Height ≈ ≈ 4.4 m 4.0 meter Adjustments are possible. Designed for Ariane-6 but seems well suited for a GSLV Mk-III launcher towards a Sun-Earth L2 orbit ISRO-ESA CMB mission Opportunity • A next generation CMB mission is challenging, but doable • Necessarily global cooperation: No single country/agency has all expertise, technology, resources, manpower to build it • Post-Planck, European CMB community proposed the Cosmic Origins Explorer (CORE) • CORE designed to be a "near-ultimate" CMB polarisation mission The proposed mission concept did not pass the initial technical and programmatic screening by ESA in January 2017. • The main issue is cost within an M-class envelope. ESA encouraged the CORE consortium to consider a joint proposal with a major international partner. Indian contribution can be significant or even dominant with right partnerships and timely investments Indian response • A cross-institutional consortium of interested cosmologists (CMB-Bharat set up formally on Jan 9th at ISRO HQ meet has ~ 50 members about 14 institutions/laboratories) • Meeting organized at ISRO-HQ on Jan 8-9, 2018 to demonstrate an Indian community capable of taking on the science. • Meeting of ESA-CORE proposal PI & co-PI with Director, SSPO, ISRO in Oct 2018. • ISRO announcement of opportunity (AO) for Astronomy missions & payloads with deadline Apr 16, 2018. • Active working groups of CMB-Bharat now towards responding to AO Scientific Objective A "near-ultimate" Cosmic Microwave Background polarisation survey Options: * Enhanced spectral characterisation * Pointed observatory mode A “Capture-all” high value science and legacy CMB mission •Extract all cosmological information available in the CMB •A unique window of opportunity: matched aspirations •Balanced profile of S&T impact and returns The Scope & Challenge Indian technical contribution Capabilities achieved within India • Service module • Design, fabrication, assembly, testing • Launch to L2 • Tracking & control • Orbit maintenance • Science data downlink • Data products and analysis • Mission planning and operation 5 Indian technical contribution Capabilities achieved with modest planned investments • Telescope and Optics • Design, fabrication, assembly, testing • Reflectors, baffling • Reimaging optics, filters • Science Payload • Design, assembly, testing 6 Indian technical contribution Capabilities achieved with long-term planned investments • Broadband photon-noise-limited sensors & readout for CMB frequency bands • Cryogenic coolers at 100mK in space 7 Indian technical contribution CMB-Bharat Working groups Cluster Physics from CMB: Lead: Subhabrata Majumdar (TIFR) Members: Suvodip Mukherjee, Dhiraj Hazra, K.P. Singh, Siddharth Savyasachi Malu, Abhirup Datta, Priyanka Singh Foregrounds and CIB: Lead: Tuhin Ghosh (NISER) Members: Rajib Saha, Soumen Basak, Pavan K. Aluri, Moumita Aich, Ranajoy Banerji, Aditya Rotti, Abhirup Datta, Pravabati Chingangbam, Sandeep Rana (List Here) Instrument science: Lead: Zeeshan Ahmed (Stanford Univ) Members: Aafaque R Khan, Rahul Datta, Mayuri S.Rao, Ritoban Thakur Inflation: Lead: L. Sriramkumar (IIT Madras) Members: Dhiraj Hazra, Anshuman Maharana, Urjit Yajnik, Raghu Rangarajan, Supratik Pal, Anjan Ananda Sen, Subodh Patil, Rajeev Kumar Jain, Gaurav Goswami, V. Sreenath, Debika Chowdhury, Pravabati Chingangbam, Moumita Aich (List here) CMB-Bharat Working groups Cosmological parameters: Lead: Dhiraj Hazra (APC, Paris NISER?,…) Members: Suvodip Mukherjee, Rajib Saha, Urjit Yajnik, Supratik Pal, Anjan Ananda Sen, Rajeev Kumar Jain, Ujjaini Alam, Barun Kumar Pal, Arindam Chatterjee, H K Jassal, Priyanka Singh Lensing: Lead: Suvodip Mukherjee (CCA, NY) Members: Dhiraj Hazra, Anjan Ananda Sen, Supratik Pal, Aditya Rotti, Shabbir Shaikh, Rajorshi Sushovan Chandra, Barun Kumar Pal, Ashish Meena, Priyanka Singh Simulations and Data Pipelines: Lead: Jasjeet Singh Bagla (IISER Mohali) Members: Soumen Basak, Tuhin Ghosh, Shamik Ghosh, Ranajoy Banerji, Rahul Kothari, Aditya Rotti, Abhirup Datta, Nishikanta Khandai Spectral Distortions: Lead: Rishi Khatri (TIFR) Members: Suvodip Mukherjee, Anjan Ananda Sen, Aditya Rotti, Subodh Patil, Rajeev Kumar Jain, Biman Nath CMB-Bharat Working groups Statistics: Isotropy and Gaussianity: Lead: Aditya Rotti (U Manchester) Members: Suvodip Mukherjee, Dhiraj Hazra, Rajib Saha, Urjit Yajnik, Shamik Ghosh, Pavan K. Aluri, Subodh Patil, Rahul Kothari, Nidhi Pant, Shabbir Shaikh, Rajorshi Sushovan Chandra, Pravabati Chingangbam, Moumita Aich, Sandeep Rana Systematics: Lead: Ranajoy Banerji (U. Oslo) Members: Abhirup Datta, (List Here) Synergy with Astrophysics: Dust in ICM/IGM, science at ~1.3 TeraHz Members: K. P. Singh, Jasjeet Singh Bagla, Priyanka Singh Synergy with ground experiments: Lead: Mayuri Sathyanarayana Rao Members: Abhirup Datta, Siddharth Malu Most CMB space mission Indian mission Planck launch 2009 launch ? Thank you !!!