Foreground & component separation section for B-Pol: from the first proposal to the new submission

1. Foreground & component separation section for B-Pol: from the first proposal to the new submission Carlo Burigana INAF-IASF Bologna, burigana@iasfbo.inaf.it B-Pol Workshop Institut d'Astrophysique de Paris 28 - 30 July 2010 C. Burigana, Paris, 28-30 July 2010, B-Pol: Foregrounds & Comp. Sep.

2. Foreground “subsection” • Galactic studies • brief review of existing all (or large coverage) sky surveys @ deg resolution: • WMAP, radio 1.4 GHz, Archeops • Galactic components of polarized microwave sky • Some comments on Galaxy modelling • Extragalactic sources • Poisson (& clustering) flucts. by polarized extragalactic sources • radio sources (various classes) • far-IR sources (various classes) • APS of the various astrophysical signals vs CMB vs noise • Mention to perspectives from future (for that time) “observations”: OCRA (30 GHz), Planck, S-PASS, PGMS, C-BASS, GEM, PILOT, SPT, SCUBA2, ALMA, POLKA, HERTZ, IRAM, … C. Burigana, Paris, 28-30 July 2010, B-Pol: Foregrounds & Comp. Sep.

3. Comparison between CMB & foreground & noise APS(from first B-Pol proposal) C. Burigana, Paris, 28-30 July 2010, B-Pol: Foregrounds & Comp. Sep.

4. Legenda of APS figure C. Burigana, Paris, 28-30 July 2010, B-Pol: Foregrounds & Comp. Sep.

5. Component separation “subsection” • Brief review of available (or “in construction”) methods • Diffuse components: non-blind, blind methods • template fitting methods, Wiener filtering & maximum entropy • ICA, FastICA, SMICA, CCA, PolEMICA • phase methods • B-Pol 1 deg: relevant for Galactic diffuse component studies • Sources • wavelet & bandpass filters, matched filter, Mexican-hat wavelet family • B-Pol 1deg: essentialy no new sources but studies down to 100 mJy level of sources already detected C. Burigana, Paris, 28-30 July 2010, B-Pol: Foregrounds & Comp. Sep.

6. Updates/Improvements? • Updates on existing / in progress / foreseen surveys/data (see e.g. talks by Simona, Ettore) • Improvements in modelling astrophysical signals (see e.g. talks by Lauranne, Richard, Jean-Philippe & notes here by Gianfranco & Anna) • Comp. sep. methods: updates in description of existing methods, but in particular: • concrete applications to B-Pol of few selected methods for representative experimental set-up? • concrete applications to B-Pol to define optimal frequencies? (… optimal for what? …) • N.B.: now the state-of-the-art is much more mature than only few years ago but … at B-Pol sensitivity level? • see e.g. talks by Jacques, Sara/Anna, Clive • Extension to higher multipoles? • Is observational strategy an issue? • Link with data analysis in general both for CMB & foreground statistical characterization C. Burigana, Paris, 28-30 July 2010, B-Pol: Foregrounds & Comp. Sep.

7. Link with CMB-Foreground APS estimation • We predict APS for CMB & foregrounds • Extracting CMB BB APS is the main cosmological goal of B-Pol • But, how much robust is our APS estimation? • Also, component separation methods (both aimed at CMB &/or at foregrounds) are interfaced with APS estimators possibly both for CS methods intrinsic needs & as final common goal • APS estimation is fundamental not only for CMB but also for foreground statistical studies, linked with physical modelling (turbolence/Kolmogorov spectrum, etc.) C. Burigana, Paris, 28-30 July 2010, B-Pol: Foregrounds & Comp. Sep.

8. C. Burigana, Paris, 28-30 July 2010, B-Pol: Foregrounds & Comp. Sep.

9. C. Burigana, Paris, 28-30 July 2010, B-Pol: Foregrounds & Comp. Sep.

10. Better definition of astrophysical goals? • Largely relies on our view of B-Pol, in particular of angular resolution • FWHM > deg  main goals only cosmological, room only for limited astrophysical studies • FWHM of 10 arcmin  additional cosmology, astrophysics-cosmology (see yesterday talks) & wide astrophysics: • Extragalactic sources (see also yesterday Richard’s talk) • Studies of Galactic sources/structures/features not only of vey diffuse emissions (see also today Jean-Philippe’s talk) C. Burigana, Paris, 28-30 July 2010, B-Pol: Foregrounds & Comp. Sep.

11. Integral counts of extragalactic sources in polarizationcontribution by G. de Zotti & A. Bonaldi (INAF-OAPd) • Radio source counts based on the De Zotti et al. (2005) model, assuming a mean polarization degree of 3%. Counts are dominated by blazars. • Counts of far-IR galaxies based on the Negrello et al. (2007) model, assuming a mean polarization degree of 1%. The bright tail is dominated by normal spiral galaxies, with a significant contribution from starburst galaxies. At 350 GHz, strongly lensed proto-spheroidal galaxies may start to show-up in polarization at the mJy level. C. Burigana, Paris, 28-30 July 2010, B-Pol: Foregrounds & Comp. Sep. – Contr. by G. de Zotti & A. Bonaldi

12. C. Burigana, Paris, 28-30 July 2010, B-Pol: Foregrounds & Comp. Sep. – Contr. by G. de Zotti & A. Bonaldi

13. C. Burigana, Paris, 28-30 July 2010, B-Pol: Foregrounds & Comp. Sep. – Contr. by G. de Zotti & A. Bonaldi

14. Summary on extragalactic sources • Since Planck will probably detect at ≥5σ only a few tens of extragalactic sources in polarization (López-Caniego et al. 2009) an accurate totally unbiased (blind) determination of the polarization properties of extragalactic sources will remain to be done and is clearly essential to put on a firm basis estimates of extragalactic source contributions to small scale polarization fluctuations. • Of course, polarization data are also of great importance per se, as the prime means to study the roles of magnetic fields in astrophysics. • Blind polarization surveys of large areas at (sub)-mm wavelengths are not feasible from the ground. C. Burigana, Paris, 28-30 July 2010, B-Pol: Foregrounds & Comp. Sep. – Contr. by G. de Zotti & A. Bonaldi

15. C. Burigana, Paris, 28-30 July 2010, B-Pol: Foregrounds & Comp. Sep.