Real-time digital signal processor implementation of self-calibrating pulse-shape discriminator for high purity germanium

Pulse-shape analysis of the ionization signals from germanium gamma-ray spectrometers is a method for obtaining information that can characterize an event beyond just the total energy deposited in the crystal. However, as typically employed, this method is data-intensive requiring the digitization, transfer, and recording of electronic signals from the spectrometer. A hardware realization of a real-time digital signal processor for implementing a parametric pulse shape is presented. Specifically, a previously developed method for distinguishing between single-site and multi-site gamma-ray interactions is demonstrated in an on-line digital signal processor, compared with the original off-line pulse-shape analysis routine, and shown to have no significant difference. Reduction of the amount of the recorded information per event is shown to translate into higher duty-cycle data acquisition rates while retaining the benefits of additional event characterization from pulse-shape analysis.Comment: Accepted by NIM

Peculiar Velocity Limits from Measurements of the Spectrum of the Sunyaev-Zel'dovich Effect in Six Clusters of Galaxies

We have made measurements of the Sunyaev-Zel'dovich (SZ) effect in six galaxy clusters at z > 0.2 using the Sunyaev-Zel'dovich Infrared Experiment (SuZIE II) in three frequency bands between 150 and 350 GHz. Simultaneous multi-frequency measurements have been used to distinguish between thermal and kinematic components of the SZ effect, and to significantly reduce the effects of variations in atmospheric emission which can otherwise dominate the noise. We have set limits to the peculiar velocities of each cluster with respect to the Hubble flow, and have used the cluster sample to set a 95% confidence limit of < 1410 km/s to the bulk flow of the intermediate-redshift universe in the direction of the CMB dipole. This is the first time that SZ measurements have been used to constrain bulk flows. We show that systematic uncertainties in peculiar velocity determinations from the SZ effect are likely to be dominated by submillimeter point sources and we discuss the level of this contamination.Comment: Submitted to Astrophysical Journal. 32 pages, 13 tables, 9 figure

The polatron: A millimeter-wave cosmic microwave background polarimeter for the OVRO 5.5 m telescope

We describe the development of a bolometric receiver designed to measure the arcminute-scale polarization of the cosmic microwave background (CMB). The Polatron will be mounted at the Cassegrain focus of the 5.5 m telescope at the Owens Valley Radio Observatory (OVRO). The receiver will measure both the Q and U Stokes parameters over a 20% pass-band centered near 100 GHz, with the input polarization signal modulated at ~0.6 Hz by a rotating, birefringent, quartz half-wave plate. In six months of observation we plan to observe ~400 2.5 arcminute pixels in a ring about the North Celestial Pole to a precision of ~6 \mu K/pixel in each of Q and U, adequate to unambiguously detect CMB polarization at levels predicted by current models

Measurement of the Polarization of the Cosmic Microwave Background

Measurement of cosmic microwave background (CMB) polarization will provide a powerful check on the model that describes CMB ΔT fluctuations as arising from density fluctuations in the early universe, break degeneracies between cosmological parameters that arise in interpreting ΔT fluctuations, and may ultimately allow detection of the stochastic gravity-wave background predicted by inflationary models. We describe the development and laboratory characterization of a bolometric experiment designed to measure the arcminute-scale polarization of the CMB. The Polatron receiver will be mounted at the Cassegrain focus of the 5.5 m telescope at the Owens Valley Radio Observatory. The receiver will measure both the Q and U Stokes parameters over a 20% pass-band centered near 100 GHz, with the input polarization signal modulated at ~ 1 Hz by a rotating, birefringent, quartz half-wave plate. In six months of observation we plan to observe ~ 400 2.5 arcminute pixels in a ring about the North Celestial Pole to a precision of ~ 5 µK per pixel in each of Q and U, adequate to unambiguously detect CMB polarization at levels predicted by current models

Cross-National Attunement to Popular Songs across Time and Place: A Sociology of Popular Music in the United States, Germany, Thailand, and Tanzania

This paper explores empirically Edward T. Hall&rsquo;s assertion about the role of musical elements, including rhythm recognition and what are called &ldquo;ear worms&rdquo; in popular culture. To test Hall&rsquo;s assertion, data were collected from the United States, Germany, Tanzania, and Thailand in 2015&ndash;2017 using a 26 brief &ldquo;song intros.&rdquo; Data were also collected from exchange students from South Korea and Turkey. Survey responses were analyzed using factor analysis in order to identify patterns of recognition. It was found that there were indeed patterns of recognition apparently reflecting national boundaries for some song recognition, but others crossed boundaries. A separate analysis of patterned recognition comparing American youth under thirty, with elders over 60 indicated that there were also boundaries between age groups. Such experiments in music recognition are an effective methodology for Culture Studies given that musical elements are tied to issues of identity, culture, and even politics. Music recognition can be used to measure elements of such subconscious habitus

Children's representations of learning through drawings

The main purpose of this paper is to describe a drawing-based method able to track down young students' representations of their own learning process. This method is used also to analyze whether the metaphors proposed by learning theorists correspond to those produced by students, and whether students' representation of the learning process is affected by demographic variables. 528 students – from ages six to 10 years old – were asked to draw and comment on the way they imagine what happens in their mind when they learn at school. Mixedmethod analyses were adopted. Firstly, the drawings were qualitatively assessed through a coding scheme; secondly, a quantitative analysis was run to study the effects of dimensions such as gender and students' grade. The results allowed us to draw two main conclusions: a) the metaphors the literature produced describe only partially how students represent their own learning processes; therefore, students learning representation can be defined as multidimensional; and b) the developmental path of learning representation is observable by grade and, to some extent, by gender