An introduction to axions and their detection

In these notes I try to introduce the reader to the topic of axions: their theoretical motivation and expected phenomenology, their role in astrophysics and as a dark matter candidate, and the experimental techniques to detect them. Special emphasis is made in this last point, for which a relatively updated review of worldwide efforts and future prospects is made. The material is intended as an introduction to the topic, and it was prepared as lecture notes for Les Houches summer school 2021. Abundant references are included to direct the reader to deeper insight on the different aspects of axion physics. Copyright I. G. Irastorza. This work is licensed under the Creative Commons Attribution 4.0 International License

Towards building a conceptual framework on intermarriage

Increasing migration worldwide and the cultural diversity generated as a consequence of international migration has facilitated the unions of people from different countries, religions, races, and ethnicities. Such unions are often celebrated as a sign of integration; however, at the same time as they challenge people's idea of us and them, intermarriages in fact still remain controversial, and even to some extent, taboo in many societies. Research and theorizing on intermarriage is conducted predominantly in the English-speaking North American and British contexts. This special issue includes empirical studies from not only the English-speaking countries such as the U.S., Canada, and the UK, but also from Japan, Sweden, Belgium, France, and Spain and demonstrate the increasingly diverse directions taken in the study of intermarriage in regards to the patterns, experiences, and social implications of intermarriages. Moreover, the articles address the assumed link between intermarriage and “integration.

Performance of the Micromegas detector in the CAST experiment

The gaseous Micromegas detector designed for the CERN Axion search experiment CAST, operated smoothly during Phase-I, which included the 2003 and 2004 running periods. It exhibited linear response in the energy range of interest (1-10keV), good spatial sensitivity and energy resolution (15-19% FWHM at 5.9keV)as well as remarkable stability. The detector's upgrade for the 2004 run, supported by the development of advanced offline analysis tools, improved the background rejection capability, leading to an average rate 5x10^-5 counts/sec/cm^2/keV with 94% cut efficiency. Also, the origin of the detected background was studied with a Monte Carlo simulation, using the GEANT4 package.Comment: Prepared for PSD7: The Seventh International Conference on Position Sensitive Detectors, Liverpool, United Kingdom, 12-16 Sep. 200

A novel large-volume Spherical Detector with Proportional Amplification read-out

A new type of radiation detector based on a spherical geometry is presented. The detector consists of a large spherical gas volume with a central electrode forming a radial electric field. Charges deposited in the conversion volume drift to the central sensor where they are amplified and collected. We introduce a small spherical sensor located at the center acting as a proportional amplification structure. It allows high gas gains to be reached and operates in a wide range of gas pressures. Signal development and the absolute amplitude of the response are consistent with predictions. Sub-keV energy threshold with good energy resolution is achieved. This new concept has been proven to operate in a simple and robust way and allows reading large volumes with a single read-out channel. The detector performance presently achieved is already close to fulfill the demands of many challenging projects from low energy neutrino physics to dark matter detection with applications in neutron, alpha and gamma spectroscopy.Comment: 13 pages, 13 figure

Using Wavelets to reject background in Dark Matter experiments

A method based on wavelet techniques has been developed and applied to background rejection in the data of the IGEX dark matter experiment. The method is presented and described in some detail to show how it efficiently rejects events coming from noise and microphonism through a mathematical inspection of their recorded pulse shape. The result of the application of the method to the last data of IGEX is presented.Comment: 14 pages, 8 figures. Submitted to Astrop. Phy