1,215 research outputs found

    Full Sky Study of Diffuse Galactic Emission at Decimeter Wavelengths

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    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

    Cosmic microwave background power spectrum estimation with the destriping technique

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    Extraction of the CMB (Cosmic Microwave Background) angular power spectrum is a challenging task for current and future CMB experiments due to the large data sets involved. Here we describe an implementation of MASTER (Monte carlo Apodised Spherical Transform EstimatoR) which exploits the destriping technique as a map-making method. In this method a noise estimate based on destriped noise-only MC (Monte Carlo) simulations is subtracted from the pseudo angular power spectrum. As a working case we use realistic simulations of the PLANCK LFI (Low Frequency Instrument). We found that the effect of destriping on a pure sky signal is minimal and requires no correction. Instead we found an effect related to the distribution of detector pointings, which affects the high multipole part of the power spectrum. We correct for this by subtracting a ``signal bias'' estimated by MC simulations. We also give analytical estimates for this signal bias. Our method is fast and accurate enough (the estimator is un-biased and errors are close to theoretical expectations for maximal accuracy) to estimate the CMB angular power spectra for current and future CMB space missions. This study is related to PLANCK LFI activities.Comment: 16 pages, 23 figures, submitted to MNRA

    A maximum likelihood approach to the destriping technique

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    The destriping technique is a viable tool for removing different kinds of systematic effects in CMB related experiments. It has already been proven to work for gain instabilities that produce the so-called 1/f noise and periodic fluctuations due to e.g. thermal instability. Both effects when coupled with the observing strategy result in stripes on the observed sky region. Here we present a maximum-likelihood approach to this type of technique and provide also a useful generalization. As a working case we consider a data set similar to what the Planck satellite will produce in its Low Frequency Instrument (LFI). We compare our method to those presented in the literature and find some improvement in performance. Our approach is also more general and allows for different base functions to be used when fitting the systematic effect under consideration. We study the effect of increasing the number of these base functions on the quality of signal cleaning and reconstruction. This study is related to Planck LFI activities.Comment: Revised version, accepted by A&A, 12 pages, 14 figure

    GAMBARAN LITERASI KESEHATAN TENTANG PERILAKU HIDUP BERSIH DAN SEHAT DI SEKOLAH PADA PESERTA DIDIK SMA ADVENT UNKLAB AIRMADIDI

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    Penelitian ini bertujuan untuk mengetahui gambaran literasi kesehatan tentang perilaku hidup bersih dan sehat di sekolah pada siswa SMA Advent UNKLAB Airmadidi. Penelitian ini akan dilakukan di SMA Advent UNKLAB Airmadidi, kelurahan Airmadidi Bawah, Kecamatan Airmadidi, Kabupaten Minahasa Utara. Penelitian ini akan dilaksanakan pada bulan Maret – Mei 2023.Jumlah populasi pada penelitian ini adalah 271 orang dan jumlah sampelnya dihitung menggunakan rumus Lemeshow adalah didapat sebanyak 82 orang.Penelitian ini menggunakan desain penelitian deskriptif kuantitatif dan teknik probability sampling.Analisis data dalam penelitian ini menggunakan analisis univariat.Instrumen yang digunakan dalam penelitian ini berupa karakteristik responden, kuisioner HLQ, laptop, printer, software statistik dan alat tulis menulis.Variabel pada penelitian ini yaitu Literasi Kesehatan tentang Perilaku Hidup Bersih dan Sehat pada peserta didik SMA Advent UNKLAB Airmadidi berdasarkan akses informasi yang di peroleh. Hasil penelitian menunjukkan bahwa data responden dengan literasi kesehatan yang baik ini sebanyak 59,8% sedangkan responden dengan literasi kesehatan yang tidak memadai terdapat 40,2%. Kesimpulan dari penelitian ini adalah bahwa gambaran literasi kesehatan pada siswa SMA Advent Airmadidi di UNKLAB sudah cukup atau dapat dikatakan baik berdasarkan data yang diperoleh dari kerja lapangan. Penerapan perilaku hidup bersih dan sehat di sekolah termasuk dalam perilaku baik. Fasilitas yang disediakan di sekolah juga cukup memadai bagi siswa untuk menerapkan perilaku hidup bersih dan sehat di sekolah

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

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    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

    Class II treatment by palatal miniscrew-system appliance: A case report

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    This case shows that using a rapid palatal expander (RPE) and then a pendulum appliance anchored to palatal miniscrews is an option for improving treatment management in a noncompliant patient requiring maxillary expansion and molar distalization in the late mixed dentition. First, an RPE was used to expand the maxillary arch. Then, a modified pendulum appliance was used to distalize the maxillary first permanent molars. Optimal positioning of two palatal miniscrews enabled both appliances to be supported by skeletal anchorage. Treatment was finished using multibracket fixed appliances, and after 2 years, skeletal Class I as well as dental Class I canine and molar relationships were achieved

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

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    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 TcT_c. We developed Ti/TiN multilayer microresonators with TcT_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

    Extracting cosmic microwave background polarisation from satellite astrophysical maps

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    We present the application of the Fast Independent Component Analysis ({\ica}) technique for blind component separation to polarized astrophysical emission. We study how the Cosmic Microwave Background (CMB) polarized signal, consisting of EE and BB modes, can be extracted from maps affected by substantial contamination from diffuse Galactic foreground emission and instrumental noise. {We implement Monte Carlo chains varying the CMB and noise realizations in order to asses the average capabilities of the algorithm and their variance.} We perform the analysis of all sky maps simulated according to the {\sc Planck} satellite capabilities, modelling the sky signal as a superposition of the CMB and of the existing simulated polarization templates of Galactic synchrotron. Our results indicate that the angular power spectrum of CMB EE-mode can be recovered on all scales up to ℓ≃1000\ell\simeq 1000, corresponding to the fourth acoustic oscillation, while the BB-mode power spectrum can be detected, up to its turnover at ℓ≃100\ell\simeq 100, if the ratio of tensor to scalar contributions to the temperature quadrupole exceeds 30%. The power spectrum of the cross correlation between total intensity and polarization, TETE, can be recovered up to ℓ≃1200\ell\simeq 1200, corresponding to the seventh TETE acoustic oscillation.Comment: 20 pages, MNRAS in pres
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