CMB signal in WMAP 3yr data with FastICA

We present an application of the fast Independent Component Analysis (FastICA) to the WMAP 3yr data with the goal of extracting the CMB signal. We evaluate the confidence of our results by means of Monte Carlo simulations including CMB, foreground contaminations and instrumental noise specific of each WMAP frequency band. We perform a complete analysis involving all or a subset of the WMAP channels in order to select the optimal combination for CMB extraction, using the frequency scaling of the reconstructed component as a figure of merit. We found that the combination KQVW provides the best CMB frequency scaling, indicating that the low frequency foreground contamination in Q, V and W bands is better traced by the emission in the K band. The CMB angular power spectrum is recovered up to the degree scale, it is consistent within errors for all WMAP channel combination considered, and in close agreement with the WMAP 3yr results. We perform a statistical analysis of the recovered CMB pattern, and confirm the sky asymmetry reported in several previous works with independent techniques.Comment: 10 pages, 7 figures, submitted to MNRA

New insights into foreground analysis of the WMAP five-year data using FASTICA

In this paper, we present a foreground analysis of the WMAP 5-year data using the FASTICA algorithm, improving on the treatment of the WMAP 3-year data in Bottino et al 2008. We revisit the nature of the free-free spectrum with the emphasis on attempting to confirm or otherwise the spectral feature claimed in Dobbler et al 2008b and explained in terms of spinning dust emission in the warm ionised medium. With the application of different Galactic cuts, the index is always flatter than the canonical value of 2.14 except for the Kp0 mask which is steeper. Irrespective of this, we can not confirm the presence of any feature in the free-free spectrum. We experiment with a more extensive approach to the cleaning of the data, introduced in connection with the iterative application of FASTICA. We confirm the presence of a residual foreground whose spatial distribution is concentrated along the Galactic plane, with pronounced emission near the Galactic center. This is consistent with the WMAP haze detected in Finkbeiner 2004. Finally, we attempted to perform the same analysis on full-sky maps. The code returns good results even for those regions where the cross-talk among the components is high. However, slightly better results in terms of the possibility of reconstructing a full-sky CMB map, are achieved with a simultaneous analysis of both the five WMAP maps and foreground templates. Nonetheless, some residuals are still present and detected in terms of an excess in the CMB power spectrum, on small angular scales. Therefore, a minimal mask for the brightest regions of the plane is necessary, and has been defined.Comment: Accepted for publication in MNRAS, 25 pages, 17 figures, 4 tables. Version with full resolution figures available at: http://www.mpa-garching.mpg.de/~bottino/downloads/bottino_etal.pd

Prácticas de bioseguridad adoptadas en grandes explotaciones de bovinos de carne de la zona Central de Chile

Bioseguridad se refiere al conjunto de acciones implementadas, orientadas a prevenir el ingreso y salida de agentes causantes de enfermedades en un área que se intenta proteger, así como también limitar su diseminación al interior de esta unidad. El objetivo de este estudio fue definir especificaciones técnicas de bioseguridad predial para rebaños de bovinos de carne y determinar el nivel de cumplimiento de estas prácticas en explotaciones de bovinos de carne de la zona central. Para ello se elaboró un Protocolo de Bioseguridad Predial, compuesto de 80 especificaciones técnicas. Este Protocolo fue evaluado mediante la aplicación de una encuesta en 10 planteles bovinos de producción de carne de ciclo completo con una masa superior a 1000 animales, ubicados en las regiones Quinta, Metropolitana y Sexta. La información obtenida se analizó en forma descriptiva y los resultados fueron expresados en porcentajes de cumplimiento. Los resultados obtenidos de este estudio indicaron que el 50,2% de las especificaciones técnicas de bioseguridad descritas son aplicadas. El mayor nivel de cumplimiento se observó en la prevención de la diseminación de agentes causantes de enfermedades (64,8%), observándose la aplicación de programas de vacunación y control de parásitos en la totalidad de los planteles. En la prevención de la salida de agentes causantes de enfermedades, se registró un nivel de cumplimiento del 40%, detectándose como prácticas habituales el envío de animales enfermos hacia otros planteles. Se observó una reducida implementación de prácticas destinadas a prevenir el ingreso de agentes causantes de enfermedades (45,7%), en especial en el ingreso de personas al plantel. Se concluye que las explotaciones de bovinos de carne evaluadas tienen riesgo de introducir y diseminar agentes causantes de enfermedades que pueden afectar la salud animal y alterar la seguridad y calidad de un producto alimenticio

Full Sky Study of Diffuse Galactic Emission at Decimeter Wavelengths

A detailed knowledge of the Galactic radio continuum is of high interest for studies of the dynamics and structure of the Galaxy as well as for the problem of foreground removal in Cosmic Microwave Background measurements. In this work we present a full-sky study of the diffuse Galactic emission at frequencies of few GHz, where synchrotron radiation is by far the dominant component. We perform a detailed combined analysis of the extended surveys at 408, 1420 and 2326 MHz (by Haslam et al. 1982, Reich 1982, Reich & Reich, 1986 and Jonas et al. 1998, respectively). Using the technique applied by Schlegel et al. (1998) to the IRAS data, we produce destriped versions of the three maps. This allows us to construct a nearly-full-sky map of the spectral index and of the normalization factor with sub-degree angular resolution. The resulting distribution of the spectral indices has an average of beta = 2.695 and dispersion sigma_{beta} = 0.120. This is representative for the Galactic diffuse synchrotron emission, with only minor effects from free-free emission and point sources.Comment: 10 pages, 16 jpeg figures, accepted to Astronomy & Astrophysics, Comments and figure adde

The Planck Low Frequency Instrument

The Low Frequency Instrument (LFI) of the "Planck Surveyor" ESA mission will perform high-resolution imaging of the Cosmic Microwave Background anisotropies at four frequencies in the 30-100 GHz range. We review the LFI main scientific objectives, the current status of the instrument design and the on-going effort to develop software simulations of the LFI observations. In particular we discuss the design status of the PLANCK telescope, which is critical for reaching adequate effective angular resolution.Comment: 10 pages, Latex (use epsfig.sty); 4 Postscript figures; Astrophys. Lett & Comm, in press. Proc. of the Conference: "The Cosmic Microwave Background and the Planck Mission", Santander, Spain, 22-25 June 199

Effect of Fourier filters in removing periodic systematic effects from CMB data

We consider the application of high-pass Fourier filters to remove periodic systematic fluctuations from full-sky survey CMB datasets. We compare the filter performance with destriping codes commonly used to remove the effect of residual 1/f noise from timelines. As a realistic working case, we use simulations of the typical Planck scanning strategy and Planck Low Frequency Instrument noise performance, with spurious periodic fluctuations that mimic a typical thermal disturbance. We show that the application of Fourier high-pass filters in chunks always requires subsequent normalisation of induced offsets by means of destriping. For a complex signal containing all the astrophysical and instrumental components, the result obtained by applying filter and destriping in series is comparable to the result obtained by destriping only, which makes the usefulness of Fourier filters questionable for removing this kind of effects.Comment: 10 pages, 8 figures, published in Astronomy & Astrophysic

Development of microwave superconducting microresonators for neutrino mass measurement in the HOLMES framework

The European Research Council has recently funded HOLMES, a project with the aim of performing a calorimetric measurement of the electron neutrino mass measuring the energy released in the electron capture decay of 163Ho. The baseline for HOLMES are microcalorimeters coupled to Transition Edge Sensors (TESs) read out with rf-SQUIDs, for microwave multiplexing purposes. A promising alternative solution is based on superconducting microwave resonators, that have undergone rapid development in the last decade. These detectors, called Microwave Kinetic Inductance Detectors (MKIDs), are inherently multiplexed in the frequency domain and suitable for even larger-scale pixel arrays, with theoretical high energy resolution and fast response. The aim of our activity is to develop arrays of microresonator detectors for X-ray spectroscopy and suitable for the calorimetric measurement of the energy spectra of 163Ho. Superconductive multilayer films composed by a sequence of pure Titanium and stoichiometric TiN layers show many ideal properties for MKIDs, such as low loss, large sheet resistance, large kinetic inductance, and tunable critical temperature $T_c$. We developed Ti/TiN multilayer microresonators with $T_c$ within the range from 70 mK to 4.5 K and with good uniformity. In this contribution we present the design solutions adopted, the fabrication processes and the characterization results

The Planck-LFI instrument: analysis of the 1/f noise and implications for the scanning strategy

We study the impact of the 1/f noise on the PLANCK Low Frequency Instrument (LFI) osbervations (Mandolesi et al 1998) and describe a simple method for removing striping effects from the maps for a number of different scanning stategies. A configuration with an angle between telescope optical axis and spin-axis just less than 90 degrees (namely 85 degress) shows good destriping efficiency for all receivers in the focal plane, with residual noise degradation < 1-2 %. In this configuration, the full sky coverage can be achieved for each channel separately with a 5 degrees spin-axis precession to maintain a constant solar aspect angle.Comment: submitted to Astronomy and Astrophysics, 12 pages, 15 PostSript figure