Showing papers by "Simon Prunet published in 2007"
University of Cambridge1, Heidelberg University2, International School for Advanced Studies3, University of Rome Tor Vergata4, University of Paris5, Lawrence Berkeley National Laboratory6, University of California, Berkeley7, University of Warsaw8, California Institute of Technology9, Institut d'Astrophysique de Paris10, University of Helsinki11, Helsinki Institute of Physics12, Max Planck Society13, University of Illinois at Urbana–Champaign14
TL;DR: This work compares the performance of multiple codes written by different groups for making polarized maps from Planck-sized, all-sky cosmic microwave background (CMB) data, and finds that all codes were able to handle the large data volume that Planck will produce.
Abstract: Aims. We compare the performance of multiple codes written by different groups for making polarized maps from Planck-sized, all-sky cosmic microwave background (CMB) data. Three of the codes are based on a destriping algorithm; the other three are implementations of an optimal maximum-likelihood algorithm.
Methods. Time-ordered data (TOD) were simulated using the Planck Level-S simulation pipeline. Several cases of temperature-only data were run to test that the codes could handle large datasets, and to explore effects such as the precision of the pointing data. Based on these preliminary results, TOD were generated for a set of four 217 GHz detectors (the minimum number required to produce I, Q, and U maps) under two different scanning strategies, with and without noise.
Results. Following correction of various problems revealed by the early simulation, all codes were able to handle the large data volume that Planck will produce. Differences in maps produced are small but noticeable; differences in computing resources are large.
66 citations
University of Cambridge1, International School for Advanced Studies2, Heidelberg University3, University of Rome Tor Vergata4, University of Paris5, University of California, Berkeley6, Lawrence Berkeley National Laboratory7, University of Warsaw8, California Institute of Technology9, University of Helsinki10, Institut d'Astrophysique de Paris11, Helsinki Institute of Physics12, Max Planck Society13, University of Illinois at Urbana–Champaign14
TL;DR: The performance of multiple codes written by different groups for making polarized maps from Planck-sized, all-sky cosmic microwave background (CMB) data is compared and the maximum-likelihood map-making codes can produce maps with lower residual noise than destriping codes.
Abstract: This paper is one of a series describing the performance and accuracy of map-making codes as assessed by the Planck CTP working group. We compare the performance of multiple codes written by different groups for making polarized maps from Planck-sized, all-sky cosmic microwave background (CMB) data. Three of the codes are based on a destriping algorithm, whereas the other three are implementations of a maximum-likelihood algorithm. Previous papers in the series described simulations at 100 GHz (Poutanen et al. 2006, A&A, 449, 1311) and 217 GHz (Ashdown et al. 2007, A&A, 467, 761). In this paper we make maps (temperature and polarisation) from the simulated one-year observations of four 30 GHz detectors of Planck Low Frequency Instrument (LFI). We used Planck Level S simulation pipeline to produce the observed time-ordered-data streams (TOD). Our previous studies considered polarisation observations for the CMB only. For this paper we increased the realism of the simulations and included polarized galactic foregrounds in our sky model, which is based on the version 0.1 of the PLANCK reference sky. Our simulated TODs comprised dipole, CMB, diffuse galactic emissions, extragalactic radio sources, and detector noise. The strong subpixel signal gradients arising from the foreground signals couple to the output map through the map-making and cause an error (signal error) in the maps. Destriping codes have smaller signal error than the maximum-likelihood codes. We examined a number of schemes to reduce this error. On the other hand, the maximum-likelihood map-making codes can produce maps with lower residual noise than destriping codes.
38 citations
Joseph Fourier University1, University of Paris2, Cardiff University3, Collège de France4, University of California, Berkeley5, European Space Research and Technology Centre6, California Institute of Technology7, Jet Propulsion Laboratory8, Institut d'Astrophysique de Paris9, Centre national de la recherche scientifique10, Sapienza University of Rome11, Princeton University12, University of Toronto13, Spanish National Research Council14, University of Minnesota15, Maynooth University16, University of British Columbia17, Landau Institute for Theoretical Physics18
TL;DR: Archeops is a balloon-borne experiment inspired by the Planck satellite and its high frequency instrument (HFI) which is designed to measure the cosmic microwave background (CMB) temperature anisotropies at high angular resolution (~12 arcmin) over a large fraction of the sky (around 30%) at 143, 217, 353, and 545 GHz.
Abstract: Aims:Archeops is a balloon-borne experiment inspired by the Planck satellite and its high frequency instrument (HFI). It is designed to measure the cosmic microwave background (CMB) temperature anisotropies at high angular resolution (~12 arcmin) over a large fraction of the sky (around 30%) at 143, 217, 353, and 545 GHz. The Archeops 353 GHz channel consists of three pairs of polarized sensitive bolometers designed to detect the polarized diffuse emission of Galactic dust. Methods: In this paper we present an update of the instrumental setup, as well as the flight performance for the last Archeops flight campaign (February 2002 from Kiruna, Sweden). We also describe the processing and analysis of the Archeops time-ordered data for that campaign, which led to measurement of the CMB anisotropy power spectrum in the multipole range l = 10-700 and to the first measurements of both the polarized emission of dust at large angular scales and its power spectra in the multipole range l = 3-70 Results: We present maps covering approximately 30% of the sky. These maps contain Galactic emission, including the Galactic plane, in the four Archeops channels at 143, 217, 353, and 545 GHz and CMB anisotropies at 143 and 217 GHz. These are one of the first sub-degree-resolution maps in the millimeter and submillimeter ranges of the large angular-scale diffuse Galactic dust emission and CMB temperature anisotropies, respectively.
35 citations
TL;DR: In this paper, the authors compared the performance of different map-making codes for making polarized maps from Planck-sized, all-sky cosmic microwave background (CMB) data.
Abstract: This paper is one of a series describing the performance and accuracy of map-making codes as assessed by the Planck CTP working group. We compare the performance of multiple codes written by different groups for making polarized maps from Planck-sized, all-sky cosmic microwave background (CMB) data. Three of the codes are based on destriping algorithm, whereas the other three are implementations of a maximum-likelihood algorithm. Previous papers in the series described simulations at 100 GHz (Poutanen et al. 2006) and 217 GHz (Ashdown et al. 2006). In this paper we make maps (temperature and polarisation) from the simulated one-year observations of four 30 GHz detectors of Planck Low Frequency Instrument (LFI). We used Planck Level S simulation pipeline to produce the observed time-ordered-data streams (TOD). Our previous studies considered polarisation observations for the CMB only. For this paper we increased the realism of the simulations and included polarized galactic foregrounds to our sky model. Our simulated TODs comprised of dipole, CMB, diffuse galactic emissions, extragalactic radio sources, and detector noise. The strong subpixel signal gradients arising from the foreground signals couple to the output map through the map-making and cause an error (signal error) in the maps. Destriping codes have smaller signal error than the maximum-likelihood codes. We examined a number of schemes to reduce this error. On the other hand, the maximum-likelihood map-making codes can produce maps with lower residual noise than destriping codes.
28 citations
Sapienza University of Rome1, Cardiff University2, Jet Propulsion Laboratory3, California Institute of Technology4, University of Toronto5, Lawrence Berkeley National Laboratory6, University of California, Berkeley7, International Federation of Accountants8, University of Oxford9, Imperial College London10, University of Rome Tor Vergata11, Massachusetts Institute of Technology12, Institut d'Astrophysique de Paris13, University of Geneva14, University of Cambridge15, University of Padua16, European Space Agency17, University of Alberta18, INAF19, Case Western Reserve University20
TL;DR: In this paper, a pixel-space analysis restricted to a portion of the BOOMERANG 2003 (B03) 145 GHz temperature map was performed to constrain the amplitude of a non-Gaussian, primordial contribution to CMB fluctuations.
Abstract: We analyze the BOOMERANG 2003 (B03) 145 GHz temperature map to constrain the amplitude of a non-Gaussian, primordial contribution to CMB fluctuations. We perform a pixel-space analysis restricted to a portion of the map chosen in view of high-sensitivity, very low foreground contamination and tight control of systematic effects. We set up an estimator based on the three Minkowski functionals which relies on high-quality simulated data, including non-Gaussian CMB maps. We find good agreement with the Gaussian hypothesis and derive the first limits based on BOOMERANG data for the nonlinear coupling parameter fNL as -300 < fNL < 650 at 68% CL and -800 < fNL < 1050 at 95% CL.
19 citations
Sapienza University of Rome1, Cardiff University2, California Institute of Technology3, University of Toronto4, University of California, Berkeley5, Lawrence Berkeley National Laboratory6, University of Rome Tor Vergata7, Imperial College London8, Massachusetts Institute of Technology9, National Institute of Geophysics and Volcanology10, University of California, Santa Barbara11, Case Western Reserve University12, University of Alberta13, Institut d'Astrophysique de Paris14
TL;DR: In this paper, the authors report results from the Boomerang 2003 flights, devoted to the measurement of intensity and polarization of the cosmic microwave background radiation (CME), and focus on the power angular power spectra and the control of possible contamination from systematic effects and foregrounds.
6 citations
University of Rome Tor Vergata1, Sapienza University of Rome2, Cardiff University3, California Institute of Technology4, University of Toronto5, Lawrence Berkeley National Laboratory6, International Federation of Accountants7, University of Oxford8, Imperial College London9, Massachusetts Institute of Technology10, National Institute of Geophysics and Volcanology11, University of California, Santa Barbara12, Case Western Reserve University13, University of Geneva14, University of Alberta15, Institut d'Astrophysique de Paris16
TL;DR: In this article, the authors analyse the 145 GHz temperature map produced from the 2003 flight of BOOMERanG in search for deviations from Gaussianity, and the preliminary results suggest that the data are fully consistent with the Gaussian hypothesis.
4 citations
Sapienza University of Rome1, Cardiff University2, Jet Propulsion Laboratory3, California Institute of Technology4, University of Toronto5, Lawrence Berkeley National Laboratory6, Space Sciences Laboratory7, International Federation of Accountants8, University of Rome Tor Vergata9, Imperial College London10, Massachusetts Institute of Technology11, Case Western Reserve University12, University of California, Santa Barbara13, University of Alberta14, National Institute of Geophysics and Volcanology15
TL;DR: The first images of the CMB with sub-horizon resolution were taken by BOOMERanG-98 and by WMAP in 1998 as mentioned in this paper, which produced maps of the Stokes parameters I, Q, U of the microwave sky.
4 citations
Sapienza University of Rome1, Cardiff University2, Jet Propulsion Laboratory3, California Institute of Technology4, University of Toronto5, Lawrence Berkeley National Laboratory6, University of California, Berkeley7, International Federation of Accountants8, University of Oxford9, Imperial College London10, University of Rome Tor Vergata11, Massachusetts Institute of Technology12, Institut d'Astrophysique de Paris13, University of Geneva14, University of Cambridge15, University of Padua16, European Space Agency17, University of Alberta18, INAF19, Case Western Reserve University20
TL;DR: In this article, a pixel space analysis restricted to a portion of the BOOMERanG 2003 (B03) 145 GHz temperature map was performed to constrain the amplitude of a non-Gaussian, primordial contribution to CMB fluctuations.
Abstract: We analyze the BOOMERanG 2003 (B03) 145 GHz temperature map to constrain the amplitude of a non Gaussian, primordial contribution to CMB fluctuations. We perform a pixel space analysis restricted to a portion of the map chosen in view of high sensitivity, very low foreground contamination and tight control of systematic effects. We set up an estimator based on the three Minkowski functionals which relies on high quality simulated data, including non Gaussian CMB maps. We find good agreement with the Gaussian hypothesis and derive the first limits based on BOOMERanG data for the non linear coupling parameter f_NL as -300
4 citations
TL;DR: In this paper, the authors give a short review of what are the motivations and difficulties of observing the Cosmic Microwave Background (CMB) polarization and how polarization information should constrain some key aspects of the early universe physics.
Abstract: In this short review, I try to give a flavor of what are the motivations
and difficulties of observing the Cosmic Microwave Background (CMB)
polarization. After describing briefly the physics of CMB polarization,
I give a snapshot of the observational status, as well as the data
processing techniques developed so far. I end up describing how polarization
information should constrain some key aspects of the early universe
physics.
1 citations