Measuring the evolution of contemporary western popular music

Popular music is a key cultural expression that has captured listeners' attention for ages. Many of the structural regularities underlying musical discourse are yet to be discovered and, accordingly, their historical evolution remains formally unknown. Here we unveil a number of patterns and metrics characterizing the generic usage of primary musical facets such as pitch, timbre, and loudness in contemporary western popular music. Many of these patterns and metrics have been consistently stable for a period of more than fifty years, thus pointing towards a great degree of conventionalism. Nonetheless, we prove important changes or trends related to the restriction of pitch transitions, the homogenization of the timbral palette, and the growing loudness levels. This suggests that our perception of the new would be rooted on these changing characteristics. Hence, an old tune could perfectly sound novel and fashionable, provided that it consisted of common harmonic progressions, changed the instrumentation, and increased the average loudness.Comment: Supplementary materials not included. Please see the journal reference or contact the author

Proton imaging apparatus for protontherapy application

Radiotherapy with protons, due to the physical properties of these particles, offers several advantages for cancer therapy as compared to the traditional radiotherapy with photons. In the clinical use of proton beams, a pCT (proton Computed Tomography) apparatus can contribute to improve the accuracy of the patient positioning and dose distribution calculation. In this paper a pCT apparatus built by the PRIMA (PRoton IMAging) Italian Collaboration will be presented and the preliminary results will be discussed

PRIMA+: A proton Computed Tomography apparatus

The proton Computed Tomography (pCT) is a medical imaging method, based on the use of proton beams with kinetic energy of the order of 250 MeV, aimed to directly measure the stopping power distribution of tissues thus improving the present accuracy of treatment planning in hadron therapy. A pCT system should be capable to measure tissue electron density with an accuracy better than 1% and a spatial resolution better than 1 mm. The blurring effect due to multiple Coulomb scattering can be mitigated by single proton tracking technique. As a first step towards pCT the PRIMA+ Collaboration built a prototype capable to carry out a single radiography and a tomographic image of a rotating object. This apparatus includes a silicon microstrip tracker to identify the proton trajectory and a YAG:Ce calorimeter to measure the particle residual energy

Charge collection measurements with p-type Magnetic Czochralski silicon single pad detectors

Abstract The charge collected from beta source particles in single pad detectors produced on p-type Magnetic Czochralski (MCz) silicon wafers has been measured before and after irradiation with 26 MeV protons. After a 1 MeV neutron equivalent fluence of 1 × 10 15 cm - 2 the collected charge is reduced to 77% at bias voltages below 900 V. This result is compared with previous results from charge collection measurements

Beam test results of 3D pixel detectors constructed with poly-crystalline CVD diamond

As a possible candidate for extremely radiation tolerant tracking devices we present a novel detector design - namely 3D detectors - based on poly-crystalline CVD diamond sensors with a pixel readout. The fabrication of recent 3D detectors as well their results in recent beam tests are presented. We measured the hit efficiency and signal response of two 3D diamond detectors with 50 × 50 μm cell sizes using pixel readout chip technologies currently used at CMS and ATLAS. In all runs, both devices attained efficiencies >98 % in a normal incident test beam of minimum ionising particles. The highest efficiency observed during the beam tests was 99.2 %

An experimental demonstration of a new type of proton computed tomography using a novel silicon tracking detector

Radiography and tomography using proton beams promises benefit to image-guidance and treatment planning for proton therapy. A novel proton tracking detector is described and experimental demon- strations at a therapy facility reported. A new type of proton CT reconstructing relative ‘scattering-power’ rather than ‘stopping-power’ is also demonstrated. Notably, this new type of imaging does not require the measurement of the residual energies of the protons. Successful tracking of protons through a thick target (phantom) has demonstrated that the tracker discussed in this paper can provide the precise directional information needed to perform proton radiography and tomography. When synchronized with a range telescope, this could enable the reconstruction of proton CT images of stopping power. Furthermore, by measuring the deflection of many protons through a phantom it was demonstrated that it is possible to reconstruct a new kind of CT image (scattering power) based upon this tracking information alone

Development of 3D detectors at FBK-irst

We report on the development of 3D detectors at Fondazione Bruno Kessler - irst in the framework of the CERN RD-50 Collaboration. Technological and design aspects dealing with the 3D Single Type Column detectors are reviewed, and selected results from the electrical and functional characterization of prototypes are reported and discussed. A new detector concept, namely 3D Double-side Double Type Column detectors, allowing for significant performance enhancement while maintaining a reasonable process complexity, is final ly addressed