Laying the foundations of tomorrow’s detection techniques Analysis of cosmic neutrinos could allow researchers to gain new insights into fundamental questions around the evolution and fate of the universe, yet detecting these particles is a complex challenge. We spoke to Dr Alina Badescu about the CosNed project’s work in helping to lay the foundations of a new technique to detect cosmic neutrinos in natural salt mines A type of elementary particle, cosmic neutrinos hold great scientific interest, enabling researchers to probe some of the most fundamental questions around the evolution and fate of the universe. Neutrinos are very hard to detect however, and even harder to detect at extremely low energies, a topic that is central to the work of the CosNeD project. “The project is focused solely on cosmic neutrinos,”says Doctor Alina Badescu, the project’s Principal Investigator, based at the University Politehnica of Bucharest. Detecting ultra high energy cosmic neutrinos has long been a major goal in research, yet this is a technically demanding challenge. “The main difficulties in detecting neutrinos are due to their small flux number, and the small probability of interaction,” explains Dr Badescu. “The latter point is exactly what makes them so interesting, as they will travel in space undeflected, indicating the direction of the high energetic source that produced them.” The project is investigating a new technique for measuring high-energy cosmic neutrinos, centred around their radio detection in natural salt mines. These salt mines have some natural advantages in terms of detecting cosmic neutrinos, as Dr Badescu explains. “We have chosen a salt dome because the
The network of antennas can determine the energy of the primary particle through the measurement of the amplitude of the radio EM field, and it can reconstruct the direction of the primary particle through the measurement of the occurrence times of the
radio impulses www.euresearcher.com
detector volume is very large and salt is so transparent to the radio waves that the spacing of detectors can be sufficiently large to enhance the effective volume and event rate. Beyond that, a salt mine is more radioquiet than other places in the world, so as to reduce artificial signals considerably, as the soil above the dome absorbs most of the radio noise. Lastly, the density of salt is higher than the density of ice or water, thus the particle shower dimension is smaller,” she outlines. Salt settlements in Romania are among the biggest in Europe, which is another important consideration. “The construction of such a detector would be a world first,” says Dr Badescu.
Salt neutrino detector There are many technical hurdles to negotiate first however. The salt neutrino detector is a complementary approach, still in the conceptual stage, that deals with the measurement of a very wide formation of natural salt with antennas. “The network of antennas can determine the energy of the primary particle through the measurement of the amplitude of the radio EM field, and it can reconstruct the direction of the primary particle through the measurement of the occurrence times of the radio impulses. In order to compensate for the small interaction probability a huge volume of detecting material is required that is “Unirea” Salt Mine (Photograph by Radu Sandovici)
found in naturally occurring bulk of dielectrics, such as natural salt domes,” explains Dr Badescu. The first step in the project would be to experimentally determine the radio attenuation length in salt, after which researchers can look towards wider objectives. “We are also interested in modelling, both theoretically and empirically, the radio wave propagation in layered, heterogeneous media,” outlines Dr Badescu. This work could hold important implications for geophysics and industry, for example in modelling the vertical profile of soil to ensure highways are constructed on stable ground. The development of indirect radio techniques for detecting cosmic neutrinos could also enable researchers to probe more deeply into fundamental questions in physics. “The enduring impact of this project will be to solve some of the outstanding conceptual problems in the origin of the high energy cosmic particles, relating to their production, acceleration and propagation mechanisms,” says Dr Badescu. CosNeD Research programs represent a main priority at the University Politehnica of Bucharest. The University has invested in a top performance research center, CAMPUS, and academic staff at the university are involved in many international research projects. The university also makes educational offers tailored to the needs of international students. Dr Badescu’s faculty offers 2 bachelor programs taught in English (one in Telecommunications, and one in Electronics) and one masters programme (“Advanced wireless telecommunication”). Dr Alina Badescu University Politehnica of Bucharest T: +40 72 396 7698 E: alinabadescu@radio.pub.ro W: http://www.radio.pub.ro/erc/ Alina-Mihaela Badescu has obtained her M.Sc. degree in Radio and Optical Telecommunications in 2006, and in 2008 - in Radio Astronomy. In 2011 she obtained her PhD degree in radio detection of astroparticles. She has worked in several research projects in the field of radio detection and telecommunications. She is affiliated to University POLITEHICA of Bucharest, Faculty of Electronics, Telecommunications and Information Technology.
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