Cosmic Microwave Cosmic Microwave Background and Planck: Background and Planck: science and challengesscience and challenges

Carlo BaccigalupiCarlo Baccigalupi

Outline Outline

CMB physicsCMB physics Status of the CMB observations and future Status of the CMB observations and future

experimental probes experimental probes The science goals of the Planck satelliteThe science goals of the Planck satellite Planck data analysis and the creation of Planck data analysis and the creation of

the Trieste Planck Analysis Center (TPAC)the Trieste Planck Analysis Center (TPAC) Opportunities and challenges for TriesteOpportunities and challenges for Trieste More talks to come…More talks to come…

CMB physicsCMB physics

CMB: from where and when?CMB: from where and when?

Opacity: Opacity: λλ = (n= (neeσσTT))-1 -1 « H« H-1-1

Decoupling: Decoupling: λλ ≈≈ H H-1-1

Free streaming: Free streaming: λλ » H » H-1-1

Cosmological expansion, Cosmological expansion, constants and baryon constants and baryon abundance conspirate to abundance conspirate to activate decoupling about activate decoupling about 300000 years after the 300000 years after the Big Bang, at about 3000 Big Bang, at about 3000 K photon temperatureK photon temperature

CMB anisotropy: phenomenologyCMB anisotropy: phenomenology

Primordial perturbations Primordial perturbations in the curvature affect all in the curvature affect all cosmological speciescosmological species

Perturbation evolution for Perturbation evolution for all components proceeds all components proceeds accordingly to the cosmic accordingly to the cosmic geometry and expansiongeometry and expansion

The anisotropy in the The anisotropy in the CMB represents the CMB represents the snapshot of cosmological snapshot of cosmological perturbations in the perturbations in the photon component only, photon component only, at decoupling timeat decoupling time

CMB physics: Boltzmann equationCMB physics: Boltzmann equation

d ɣ black body = metric + Compton scattering dt

d baryons+leptons = metric + Compton scattering dt

CMB physics: dark sectorCMB physics: dark sector

d Ʋ black body = metric + weak interactionweak interaction dt d dark matter = metric + weak interactionweak interaction dt

metric = ɣ + Ʋ + baryons + leptons + dark matter

CMB physics: metricCMB physics: metric

CMB Physics: Compton scatteringCMB Physics: Compton scattering

Compton scattering is Compton scattering is anisotropicanisotropic

An anisotropic incident An anisotropic incident intensity determines a intensity determines a linear polarization in the linear polarization in the outgoing radiationoutgoing radiation

At decoupling that At decoupling that happens due to the finite happens due to the finite width of last scattering width of last scattering and the cosmological and the cosmological local quadrupolelocal quadrupole

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CMB anisotropy: total intensityCMB anisotropy: total intensity

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CMB anisotropy: polarizationCMB anisotropy: polarization

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Gradient (E):Curl (B):

Status of the CMB observations Status of the CMB observations and future experimental probesand future experimental probes

CMB angular power spectrumCMB angular power spectrum

Angle ≈ 200/l degrees

CMB angular power spectrumCMB angular power spectrum

Angle ≈ 200/l degrees

Primordial power

Gravity waves

Acoustic oscillations

Reionization

Lensing

Known CMB angular power spectrumKnown CMB angular power spectrum

Angle ≈ 200/l degrees

CMB angular power spectrumCMB angular power spectrum

boomerang

dasi

Wmap+CBI+ACBAR

CMB anisotropy statistics: unknown, CMB anisotropy statistics: unknown, probably still hidden by systematicsprobably still hidden by systematics Evidence for North south Evidence for North south

asymmetry (Hansen et al. asymmetry (Hansen et al. 2005)2005)

Evidence for Bianchi Evidence for Bianchi models (Jaffe et al. 2006)models (Jaffe et al. 2006)

Poor constraints on Poor constraints on inflation, the error is inflation, the error is about 100 times the about 100 times the predicted deviations from predicted deviations from Gaussianity (Komatsu et Gaussianity (Komatsu et al. 2003)al. 2003)

Lensing detection out of Lensing detection out of reachreach

Other cosmological backgroundsOther cosmological backgrounds

Neutrinos: abundance comparable to Neutrinos: abundance comparable to photons photons , decoupling at MeV , decoupling at MeV , cold as , cold as photons photons , weak interaction , weak interaction

Gravity waves: decoupling at Planck Gravity waves: decoupling at Planck energy energy , abundance unknown , abundance unknown , , gravitational interaction gravitational interaction

Morale: dig into the CMB, still for many Morale: dig into the CMB, still for many years…that’s the best we have for long…years…that’s the best we have for long…

Forthcoming CMB polarization probesForthcoming CMB polarization probes

PlanckPlanck EBEx (US, France, Italy), EBEx (US, France, Italy),

baloon, same launch time baloon, same launch time scale as Planck for the scale as Planck for the north american flightnorth american flight

QUIET (US, UK), ground QUIET (US, UK), ground basedbased

Clover (UK, …)Clover (UK, …) BrainBrain …… Complete list available at Complete list available at

the Lambda archive the Lambda archive lambda.gsfc.nasa.govlambda.gsfc.nasa.gov

Cosmic vision beyond EinsteinCosmic vision beyond Einstein

NASA and ESA put out NASA and ESA put out separate calls of separate calls of opportunity for a opportunity for a polarization oriented polarization oriented future (2020 at least) future (2020 at least) CMB satelliteCMB satellite

Technologies, design, Technologies, design, options for joint or options for joint or separate missions are separate missions are being discussed in being discussed in these monthsthese months

Cosmic vision program logo

Beyond einstein logo

The science goals of the The science goals of the Planck satellitePlanck satellite

Source: Planck scientific program bluebook, Source: Planck scientific program bluebook, available at www.rssd.esa.int/Planckavailable at www.rssd.esa.int/Planck

PlanckPlanck

Hardware: third generation Hardware: third generation CMB probe, ESA medium CMB probe, ESA medium size mission, NASA (JPL, size mission, NASA (JPL, Pasadena) contributionPasadena) contribution

Software from 400 Software from 400 collaboration members in collaboration members in EU and USEU and US

Two data processing Two data processing centers (DPCs): Paris + centers (DPCs): Paris + Cambridge (IaP + IoA), Cambridge (IaP + IoA), Trieste (OAT + SISSA)Trieste (OAT + SISSA)

Planck contributorsPlanck contributors

Planck contributorsPlanck contributors

Davies

Berkeley

Pasadena

Minneapolis

Rome

HelsinkiCopenhagenBrighton

Oviedo

SantanderPadua

Bologna

TriesteMilan

ParisToulouse

Oxford

CambridgeMunich

Heidelberg

Planck data processing sitesPlanck data processing sites

TriesteParisCambridge

Planck data deliverablesPlanck data deliverables All sky maps in total All sky maps in total

intensity and polarization, intensity and polarization, at 9 frequencies between at 9 frequencies between 30 and 857 GHz30 and 857 GHz

Angular resolution from Angular resolution from 33’ to 7’ between 30 and 33’ to 7’ between 30 and 143 GHz, 5’ at higher 143 GHz, 5’ at higher frequenciesfrequencies

S/N S/N ≈ 10 for CMB in ≈ 10 for CMB in total intensity, total intensity, per per resolution elementresolution element

Catalogues with tens of Catalogues with tens of thousands of extra-thousands of extra-Galactic sourcesGalactic sources

Planck scientific deliverables: CMB Planck scientific deliverables: CMB total intensity and the era of imagingtotal intensity and the era of imaging

Planck scientific deliverables:Planck scientific deliverables:CMB polarizationCMB polarization

Planck and polarization CMB B modesPlanck and polarization CMB B modes

Planck scientific deliverables: Planck scientific deliverables: cosmological parameterscosmological parameters

Non-CMB Planck scientific deliverablesNon-CMB Planck scientific deliverables

Thousands of galaxy clustersThousands of galaxy clusters Tens of thousands of radio and infrared Tens of thousands of radio and infrared

extra-Galactic sourcesextra-Galactic sources Templates for the diffuse gas in the Templates for the diffuse gas in the

Galaxy, from 30 to 857 GHzGalaxy, from 30 to 857 GHz ……

Planck data analysisPlanck data analysis

Planck scanning strategy and Planck scanning strategy and data collectiondata collection

Two complete all sky surveys in 14 months Two complete all sky surveys in 14 months Data comes in the form of Time Ordered Data Data comes in the form of Time Ordered Data

(TOD) from each one of the 63 detectors, (TOD) from each one of the 63 detectors, sampling the sky at tens of kHzsampling the sky at tens of kHz

10 Tb disk space10 Tb disk space

Planck data analysisPlanck data analysis

Level S: mission simulationLevel S: mission simulation Level 1: telemetry processing and Level 1: telemetry processing and

instrument control, early source catalogueinstrument control, early source catalogue Level 2: calibration and map-makingLevel 2: calibration and map-making Level 3: component separation, CMB Level 3: component separation, CMB

spectrum estimation, source cataloguespectrum estimation, source catalogue Level 4: product deliveryLevel 4: product delivery

Planck data analysisPlanck data analysis

Level S: mission simulationLevel S: mission simulation Level 1: telemetry processing and Level 1: telemetry processing and

instrument control, early source catalogueinstrument control, early source catalogue Level 2: calibration and map-makingLevel 2: calibration and map-making Level 3: component separation, CMB Level 3: component separation, CMB

spectrum estimation, source cataloguespectrum estimation, source catalogue Level 4: product deliveryLevel 4: product delivery

DPCDPC

Planck schedulePlanck schedule

Launch between agoust 2007 and 2008Launch between agoust 2007 and 2008 Observations start after about two monthsObservations start after about two months 14 months of data acquisition14 months of data acquisition 1 year data proprietary period1 year data proprietary period 1 year data release, publications, archive1 year data release, publications, archive Over within 2012Over within 2012

Planck DPC schedulePlanck DPC schedule Software acquisition and integration ongoingSoftware acquisition and integration ongoing Ongoing hardware acquisition: minimum Ongoing hardware acquisition: minimum

requirement for a 128 Opteron processors requirement for a 128 Opteron processors parallel machine, 2 or 4 Gb RAM per CPU, 10 parallel machine, 2 or 4 Gb RAM per CPU, 10 Tb disk spaceTb disk space

Hardware and software installation and Hardware and software installation and maintainancemaintainance

Data analysis pipeline testing beginning april Data analysis pipeline testing beginning april 20062006

Pipeline for the operations ready 6 months Pipeline for the operations ready 6 months before launchbefore launch

Planck DPC work statusPlanck DPC work status

Pipeline simulations ongoing for the 70 Pipeline simulations ongoing for the 70 GHz detectors, GHz detectors,

Results review from the pipeline testing Results review from the pipeline testing web pageweb page

More details in the forthcoming talk by More details in the forthcoming talk by Sam Leach, May 2006Sam Leach, May 2006

Opportunities and Opportunities and challenges for Triestechallenges for Trieste

Opportunities Opportunities

You may exploit the proprietary period of data to You may exploit the proprietary period of data to propose and carry out your own science, propose and carry out your own science, provided that there is no overlap with the official provided that there is no overlap with the official deliverablesdeliverables

You may provide ideas and algorithms, and take You may provide ideas and algorithms, and take the opportunity of being in physical contact with the opportunity of being in physical contact with the DPC in order to carry out your research the DPC in order to carry out your research

With the exception of the Paris Cambridge With the exception of the Paris Cambridge parallel DPC, none in the world will have this parallel DPC, none in the world will have this opportunity during the Planck proprietary periodopportunity during the Planck proprietary period

Challenges Challenges

The scientific impact of Planck is huge: Galactic The scientific impact of Planck is huge: Galactic structure, populations of galaxies and galaxy structure, populations of galaxies and galaxy clusters, dark matter, energy, early universeclusters, dark matter, energy, early universe

We will suffer a tremendous international We will suffer a tremendous international attention and pressure during the operation and attention and pressure during the operation and data reduction phases (just look how many times data reduction phases (just look how many times the keyword “Planck satellite” appears in modern the keyword “Planck satellite” appears in modern astrophysics and cosmology literature)astrophysics and cosmology literature)

A community may form on the basis of a large A community may form on the basis of a large project like Planck, as already happened for project like Planck, as already happened for cosmologists in europecosmologists in europe

Trieste Planck Analysis Center (TPAC)Trieste Planck Analysis Center (TPAC)

joint OAT and SISSA initiative lasting for the joint OAT and SISSA initiative lasting for the Planck operation timePlanck operation time

Different from DPC: the interface is with the Different from DPC: the interface is with the community in Trieste, not ESAcommunity in Trieste, not ESA

Goal: full exploitation of the Planck data, Goal: full exploitation of the Planck data, covering non-Planck deliverables which might be covering non-Planck deliverables which might be of interest for our community in Triesteof interest for our community in Trieste

Tasks: driver for local interests in Planck, Tasks: driver for local interests in Planck, management of hardware and human resources management of hardware and human resources in the Trieste areain the Trieste area

Conclusions Conclusions Together with other experiments (LHC, GWs and DM Together with other experiments (LHC, GWs and DM

searches, …), Planck is one of the major forthcoming searches, …), Planck is one of the major forthcoming appointments for cosmology, particle physics and appointments for cosmology, particle physics and astrophysics astrophysics

It happens to have one of the two data analysis here in It happens to have one of the two data analysis here in TriesteTrieste

If it works instrumentally, a world wide community, of If it works instrumentally, a world wide community, of particle physicists, cosmologists and astrophysicists, will particle physicists, cosmologists and astrophysicists, will have the eyes fixed on ushave the eyes fixed on us

The challenge is not only allocating resources, but The challenge is not only allocating resources, but developing a community, understanding that the success developing a community, understanding that the success in the data analysis process is crucial for how the in the data analysis process is crucial for how the community trusts us on large scale international projectscommunity trusts us on large scale international projects

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CMB physics: Boltzmann equationCMB physics: Boltzmann equation

d ɣ black body = + dt

d baryons+leptons = + dt

Dark energy, gravity and CMBDark energy, gravity and CMB Relation between dark energy and gravity (Perrotta Relation between dark energy and gravity (Perrotta

et al.)et al.) Production of Boltzmann codes for cosmological Production of Boltzmann codes for cosmological

perturbations with dark energy and scalar-tensor perturbations with dark energy and scalar-tensor gravity theories, (Perrotta, Baccigalupi, Acquaviva)gravity theories, (Perrotta, Baccigalupi, Acquaviva)

N-body and strong lensing simulations in dark N-body and strong lensing simulations in dark energy cosmologies (collaboration with Matthias energy cosmologies (collaboration with Matthias Bartelmann at Heidelberg, Klaus Dolag at MPA, Bartelmann at Heidelberg, Klaus Dolag at MPA, …)…)

Constraints on scalar-tensor gravity from CMB and Constraints on scalar-tensor gravity from CMB and large scale structure (Acquaviva, Leach et al., large scale structure (Acquaviva, Leach et al., 2005, in collaboration with Andrew Liddle, Sussex)2005, in collaboration with Andrew Liddle, Sussex)

Theory of the weak gravitational lensing (Acquaviva Theory of the weak gravitational lensing (Acquaviva et al. 2004)et al. 2004)

Weak lensing on CMB and implications for the dark Weak lensing on CMB and implications for the dark energy (Giovi et al. 2005, Acquaviva et al. 2005)energy (Giovi et al. 2005, Acquaviva et al. 2005)

CMB foreground studies and data analysis CMB foreground studies and data analysis algorithm design (Stivoli et al., collaboration with algorithm design (Stivoli et al., collaboration with people at LBL Berkeley, …)people at LBL Berkeley, …)

Direct involvement in the EBEx experiment (Shaul Direct involvement in the EBEx experiment (Shaul Hanany PI, university of MInnesota) for measuring Hanany PI, university of MInnesota) for measuring the CMB B modes from primordial gravity wavesthe CMB B modes from primordial gravity waves

More than 30 referred papers on these issues in the More than 30 referred papers on these issues in the past 5 years, three PhD thesis, one NASA Long past 5 years, three PhD thesis, one NASA Long Term Space Astrophysics program funded (2004-Term Space Astrophysics program funded (2004-2009, about 0.5 million dollars), about ten students 2009, about 0.5 million dollars), about ten students and post-docs (Berkeley, SISSA, Trieste university and post-docs (Berkeley, SISSA, Trieste university and observatory, …) currently workingand observatory, …) currently working

Figure on top: CMB spectra in dark energy cosmologies Figure on top: CMB spectra in dark energy cosmologies (Perrotta et al. 2000)(Perrotta et al. 2000)Bottom: the EBEx forecasted performance on B modes Bottom: the EBEx forecasted performance on B modes detection from primordial gravitational wavesdetection from primordial gravitational waves

The promise of PlanckThe promise of Planck All sky survey of CMB temperature All sky survey of CMB temperature

and polarization with 5 arcminutes and polarization with 5 arcminutes angular resolutionangular resolution

Cosmic variance limited up to the Cosmic variance limited up to the nominal resolution in temperature, and nominal resolution in temperature, and up to 10 arcminutes in polarizationup to 10 arcminutes in polarization

Frequency range from 30 to 857 GHzFrequency range from 30 to 857 GHz Cosmological science goals: percent Cosmological science goals: percent

precision or better on the global precision or better on the global cosmic geometry, abundance of dark cosmic geometry, abundance of dark and baryonic matter, dark energy and baryonic matter, dark energy dynamics, reionization optical depth, dynamics, reionization optical depth, spectrum and statistics of primordial spectrum and statistics of primordial perturbations, abundance of cosmic perturbations, abundance of cosmic gravitational wavesgravitational waves

Secondary goals: discovery of Secondary goals: discovery of thousands of galaxy clusters, radio thousands of galaxy clusters, radio and infrared point sources, physics of and infrared point sources, physics of the diffuse gas in the Milky Way the diffuse gas in the Milky Way

Figures reproducing simulations carried out at the Trieste Figures reproducing simulations carried out at the Trieste Data Processing Center (DPC) and NERSC (LBL, Berkeley) Data Processing Center (DPC) and NERSC (LBL, Berkeley)

Planck factsPlanck facts ESA medium size mission, the first one of the third generation CMB ESA medium size mission, the first one of the third generation CMB

experiments, launch in Agoust 2007experiments, launch in Agoust 2007 Instrument mainly built by ESA, with a participation from NASA (JPL, Instrument mainly built by ESA, with a participation from NASA (JPL,

Pasadena)Pasadena) World wide scientific collaboration for the data exploitation, the keyword World wide scientific collaboration for the data exploitation, the keyword

``Planck satellite” appears hundreds of times in the abstract of astronomy ``Planck satellite” appears hundreds of times in the abstract of astronomy papers (font: NASA ADS)papers (font: NASA ADS)

Two separate Data Processing Centers (DPCs): Trieste (OAT+SISSA, Two separate Data Processing Centers (DPCs): Trieste (OAT+SISSA, channels from 30 to 70 GHz), Paris and Cambridge (IAP and IoA, channels channels from 30 to 70 GHz), Paris and Cambridge (IAP and IoA, channels from 100 to 857 GHz)from 100 to 857 GHz)

One year observation time, first results released to the community in late One year observation time, first results released to the community in late 2008 (early release compact source catalogue) and middle 2009 (main 2008 (early release compact source catalogue) and middle 2009 (main scientific results)scientific results)

Planck people currently at SISSA: 2 staff, 3 post-docs, 3 PhD students; a Planck people currently at SISSA: 2 staff, 3 post-docs, 3 PhD students; a SISSA Planck plan for long term recruitment starting from the PhD SISSA Planck plan for long term recruitment starting from the PhD admission in april 2006 is being submitted to the school senate (January admission in april 2006 is being submitted to the school senate (January 2006)2006)