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Spectral Distortions of CMB

Spectral Distortions of CMB. C. Burigana, A. De Rosa, L. Valenziano, G. Morgante, F. Villa, R. Salvaterra, P. Procopio and N. Mandolesi. Anisotropies. Angular power spectrum. Example:. Polarization. Scattering Thomson of radiation with quadrupole anisotropy generates linear polarization.

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Spectral Distortions of CMB

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  1. Spectral Distortions of CMB C. Burigana, A. De Rosa, L. Valenziano, G. Morgante, F. Villa, R. Salvaterra, P. Procopio and N. Mandolesi

  2. Anisotropies Angular power spectrum Example: Polarization Scattering Thomson of radiation with quadrupole anisotropy generates linear polarization P 2 = Q 2 + U 2 Spectrum Photon distribution function Cosmic Microwave Background Radiation

  3. Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi CMBR Redshift T0 = 2.725 ± 0.002 °K (Mather et al. 1999) Dimensioneless frequency SPECTRUM Has the CMBR a black body spectrum?

  4. Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi CMB Spectrum measuresWP 1430 – C. Burigana, N. Mandolesi, L. Valenziano Recent measures of CMB spectrum (collected by Burigana and Salvaterra, 1999) >1cm: typical error > 0.1 K FIRAS measures: typical error ±0.0001 K

  5. Impact of various sources of errors: note the atmosphere relevance

  6. Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi In the primordial universe some processes can lead the matter-radiation fluid out of the thermal equilibrium (energy dissipation because of density fluctuations,Physical processes out of the equilibrium, radiative decay of particles, energy release related to the first stages of structures formation, free-free distortions) The photon distribution function isn’t a Planckian one An extremely precise fortran based code, able to simulate the effects of the primordial physical processes that can affect the thermodynamic equilibrium of the CMBR KYPRIX Spectral distortions The Kompaneets equation in cosmological contest provides the best tool to compute the evolution of the photon distribution function, but a numerical code is needed!

  7. Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi today BIG BANG z zterm zBE z zric Superposition of black bodies Bose-Einstein like spectrum where with µ function of X Cosmological applications Primordial distortions Free-free distortions Late distortions Related (mainly) to the reionization history of the universe Cosmological application of a numerical code for the solution of the Kompaneets equation, P.Procopio and C.Burigana, INAF-IASF Bologna, Internal Report, 421

  8. Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi Free-free Late Comptonization like Middle age Early Bose-Einstein like Theoretical CMB Spectral Distortions Distorted spectra in the presence of a late energy injection with Δ/i= 5 x 10-6 plus an early/intermediate energy injection with Δ/i= 5 x 10-6 occurring at yh=5, 1, 0.01 (from the bottom to the top; in the figure the cases at yh=5 and 1 are indistiguishable at short wavelengths; solid lines) and plus a free-free distortion with yB=10-6 (dashes).

  9. Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi Cosmological application Te/TR = 104 zR = 20 d/ = 10-5 One of the representative cases Distortions due to reionization of the universe at low redshifts m = 1  = 0 m = 0.29  = 0.73

  10. Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi In the Planckian Hypothesis: limits achievable with a new low frequency experiment – DIMES Example: 6 freq. channels between 2 & 90 GHz Limits achievable with a low frequency experiment with the same FIRAS sensitivity Current limits Hypothesis to be checked Burigana and Salvaterra, 2003 Cosmic time

  11. CMB spectrum: Key parametersConfiguration A and B • Frequency operating range: 0.4 – 50 GHz (75 - 0.6 cm) • Spectral resolution: 10% • Angular resolution: 7°/8° • Sensitivity: < 1 mK sec-1/2 • Field of View: > 104 deg2 • Final sensitivity (E.O.L) better than 0.1 mK per resolution element • Low sidelobes optics • Ground shield • avoid ground signal pickup • thermal stability Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi

  12. Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi Return Loss < -60dB in the whole frequency range Intercalibration between frequency bands better than 30 K Thermal stability better than 1 mK with well sampled temperature monitoring (temperature accuracy better than 10 K) Calibrator requirements The ARCADE calibrator

  13. Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi Radiometers • Differential radiometers (using low noise amplifiers) • Absolute calibration One of the ARCADE radiometers (Kogut, 2002)

  14. Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi Sketch of the large payload Mass: ~1000 Kg, height~ 6 m, deployed in a shaded crater

  15. Scientific performance as function of (low) frequency coverage C = 2, 5, 8 freq. channels, 0.48, 1.9, 7.54 cm D = 3, 6, 9 freq. channels, 0.75, 3.0, 11.9 cm E = 3, 5, 7 freq. Channels, 0.75, 1.9, 4.75 cm R = recent data @ l ≥ 1cm F = COBE/FIRAS Note that even with observations @ l ≤ 5cm the improvement is very good!

  16. Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi New Concept Design Requirements • Mass < 300 Kg • Simplify cooling system • Location at the pole • Continuous operation (day and night) • Simplify pointing system • Autonomous, unmanned operation • Simplify deployment

  17. Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi Reduce Dimension and Mass • Reduce the number of channels • Use a smaller payload • Use a smaller cooler • Select highest frequency bands • Reduce horn and calibrator dimension • Enlarge FOV (14° FWHM) • Reduce horn dimensions • Passive cooling for the optics • Use a smaller cooler • Introduce steerable optical system • Reduce horn dimension • Avoid an alt-az mounting

  18. Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi New Location • Select a location at the Pole • Reduce the size of passive cooling radiators • Reduce the observed portion of the sky (acceptable from the scientific point of view) • Avoid rover and deployment system (reduce mass) • Shaded crated location not strictly required • Simplified deployment on the final site • Operation on the landing module possible • Power generation from solar panels on the payload • Operation from the near side of the Moon • Higher frequency less affected by man-made interference

  19. Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi New Payload Concept (conf. E) • 3 channels • 6 GHz • 15 GHz • 63 GHz • FOV: 14 deg • Passive cooling for the optics • Steerable optical element at horn aperture 6GHz Channel 15GHz Channel Steerable Mirror Feed Horn 63GHz Channel Absolute Reference@4K Internal Reference @4K Thermal Link @4K Thermal Link @4K Cold Head Radiometer @4K

  20. New Payload Concept 15GHz Channel 6GHz Channel • Pointing system obtained using steerable mirrors and Moon rotation 63GHz Channel Cold Head Electonics box Compressor Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi

  21. Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi Location • Location at the Pole • Passive cooling possible. Smaller radiators • Easy deployment, unmanned operation • Shields deployed in-situ • Operation from the lander possible • Solar panels on the payload Instrument External passive cooling Shield Internal passive cooling shield Middle Shield Cooler’s Radiators Solar panel

  22. Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi • Estimated mass: < 200 Kg • In situ overall dimension: diameter: 8 m, height: 3 m • Passive shield deployed • Estimated power requirements: 3 kW • Continuous operation possible

  23. Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi CONCLUSIONS • The Moon is a unique opportunity for accurate cm & dm CMB spectrum measures free from atmosphere contamination • dm observations requires ≈ 103 Kg experiments • cm observations need ≈102 Kg experiments and represents, @ 0.1 mK sensivity, a great improvement with respect to the current observation status in particular for free-free distortions & BE-like (early) distortions • A compact design for early cm experiments has been proposed • Definitive cm & dm missions will map the cosmic thermal history with high precision up redshifts of ~ 107

  24. Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi Thanks for the attention!

  25. Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi

  26. KYPRIX Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi Input parameters a)cosmological par. b)integration par. MAIN PROGRAM Initialization of the solution vector U FUNCTION D03PCF For specific phys. quant. Cosmic exp Subroutine for boundary cond. in point A Subroutine PDEDEF Discretization of the Kompaneets Discretization in the x axis Increasing time y Output files (,t) Integral quan. Computation of the rates of the physical processes Subroutine for boundary cond. in point B How does it work?

  27. Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi KYPRIX’ update(s) ‘90 first KYPRIX release by Carlo Burigana 2004-2005 update related to the NAG libraries* sensitivity e efficiency increased** introduction of the cosmological constant** 2006-2007 CPU platform transfer (still in progress) activity update related to the relative abundances of H and He introduction of the ionization fraction of e- * Updating a numerical code for the solution of the Kompaneets equation in cosmological context, P.Procopio and C.Burigana, INAF-IASF Bologna, Internal Report, 419; **Accuracy and performance of a numerical code for the solution of hte Kompaneets equation in cosmological context, P.Procopio and C.Burigana, INAF-IASF Bologna, Internal Report, 420;

  28. Frascati workshop, May 7, 2007 - Burigana, De Rosa, Valenziano, Morgante, Villa, Salvaterra, Procopio, Mandolesi Nowday, the most precise measurements related to the parameters of the standard model (of the universe) are those realized by the NASA satellite WMAP • optical depth of the universe =0.09 +- 0.03 (3-years WMAP data) Effects of a reionization are visible in all the properties of the CMBR: --- Temperature anisotropies suppression at high multipoles* --- gain of power in T-E cross-correlation PS and in the E and B modes mainly at low and middle multipoles --- raising of free-free and compotonization like distortions in the spectrum Given that, we need a performing tool able to simulate the stages of evolution of the reionization as better as possible not only for effects related to the anisotropies, but also for what concern the CMBR spectrum *Planck-LFI scientific goals: implications for the reionization history L.Popa, C.Burigana, N.Mandolesi,…,P.Procopio,et. al., Publ. By New Astronomy Reionization

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