First Calorimetric Measurement of OI-line in the Electron Capture Spectrum of 163^{163}Ho

The isotope $^{163}$Ho undergoes an electron capture process with a recommended value for the energy available to the decay, $Q_{\rm EC}$, of about 2.5 keV. According to the present knowledge, this is the lowest $Q_{\rm EC}$ value for electron capture processes. Because of that, $^{163}$Ho is the best candidate to perform experiments to investigate the value of the electron neutrino mass based on the analysis of the calorimetrically measured spectrum. We present for the first time the calorimetric measurement of the atomic de-excitation of the $^{163}$Dy daughter atom upon the capture of an electron from the 5s shell in $^{163}$Ho, OI-line. The measured peak energy is 48 eV. This measurement was performed using low temperature metallic magnetic calorimeters with the $^{163}$Ho ion implanted in the absorber. We demonstrate that the calorimetric spectrum of $^{163}$Ho can be measured with high precision and that the parameters describing the spectrum can be learned from the analysis of the data. Finally, we discuss the implications of this result for the Electron Capture $^{163}$Ho experiment, ECHo, aiming to reach sub-eV sensitivity on the electron neutrino mass by a high precision and high statistics calorimetric measurement of the $^{163}$Ho spectrum.Comment: 5 pages, 3 figure

Participatory online environmental education at the Open University UK

The role of education in helping our societies put sustainability into practice is crucial. The motivation, awareness and empowerment, necessary for citizens to understand the concept and take part in its operationalisation, ought to emerge from environmental education, since we might encounter some difficulty when trying to teach, or impose these notions in a theoretical way. In developing environmental courses, we therefore ought to progressively replace pedagogical approaches based on (relatively 'authoritarian') transfers of information with more interactive and collaborative learning processes: citizens' participation can start with the creation of communities of learners. This paper describes the construction of two web courses: a first level teaching module on environmental systems and a third level interdisciplinary environmental course, both developed at the Open University, specialised in distance and open learning. The themes of the course include participatory processes in decision-making, the perception and representation of environmental systems, alternative leadership, biodiversity, climate change and integrated water management, environmental action and governance. The concepts focused on include sustainability, complexity, uncertainty, globalisation and 'systemic problem solving'. In both courses, the overall pedagogical process is based on the notion of environmental governance. This means that the web has been chosen as a learning platform, because - it provides various types of up to date information as well as archives, - it allows various types of users to communicate between different countries, and also - it encourages collaborative and interactive learning. This paper describes the experience of the author in creating web environmental courses at the Open University. Components of the courses such as interactive activities are discussed, as well as the pedagogical focus progressively shifted towards more participatory processes of learning

Ireland and the Nice Treaty. ZEI Discussion Paper: 2002, C 115

[Introduction.] The experience in Ireland of conducting two referenda on the Nice Treaty: Just for the record, let me remind you that the first referendum was held in June 2001, when the result was just under 54% against and just over 46% per cent in favour. The turnout was just under 35%, the second lowest in the history of referenda in Ireland and by far the lowest in referenda related to Europe. In the second referendum, held on October 19 last, there was a dramatic turn-around; 63% said "yes", 37% "no" and 51% of the electorate failed to vote. Those among you who possess agile mathematical minds will be able to work out pretty quickly that the "no" vote changed little between the two referenda; from just over 20% of the vote the first time to around 18% last month. The key to the positive result the second time around, therefore, was the higher turnout, even though half of the electorate stayed away from the polls. Put another way, many voters who are inclined to be well disposed towards the EU and who abstained last year actually turned out this time. You might well wonder why a country which has enjoyed such largesse from the EU’s coffers should appear to be so reluctant to vote in favour of further integration and enable our less-fortunate neighbours in central and eastern Europe to share in the same good fortune. Had the EU not, after all, been a major factor in the creation of the phenomenon which has come to be known as the Celtic Tiger economy

Demonstration of wavelength packet switched radio-over-fiber system

The authors present a novel concept of employing optical wavelength packet switching in radio-over-fiber access networks. In such a system, the tunable laser (TL) would be employed as a transmitter in the central station. The optical carrier generated by this device would be externally modulated with the data signal upconverted to an RF frequency before being sent to the appropriate base station (BS). If each of the BSs is assigned a unique wavelength, the addressing and routing of traffic could be performed on a packet-by-packet basis with the TL switching between the wavelength assigned to different BS

Assessing the impact of amended building regulations on the operations of UK construction companies

The UK government continues to make regular amendments to building regulations. This is in order to keep these regulations relevant to today’s prevailing construction environment. More recently, UK building regulations have been amended to facilitate the introduction of the sustainability concepts in UK building design and delivery. This paper examines the impact that these amendments on the operations of UK Construction companies. To conduct the study, five major building practitioners were interviewed. We found from this preliminary study that changes to building regulations do have a considerable impact on the operations of UK Construction companies. It is however important to highlight that a full assessment of the impact of these changes in building regulations is still not fully assessed due to the limitations with the sample size

Practicing Your Protocols

The purpose of this resource is to have students learn to use the hydrology instruments and collect the hydrology data accurately. In the classroom, students practice using the instruments or kits for protocols, exploring the range of measurements and sources of variation and error. Educational levels: Primary elementary, Intermediate elementary, Middle school, High school

A Possible Detection of the Cosmic Antineutrino Background in the Presence of Flavor Effects

Lusignoli and Vignati have recently pointed out that it is in principle possible to directly detect the cosmic antineutrino background by using the rather stable isotope holmium-163 as a target, which can decay into dysprosium-163 via electron capture (EC) with a very small energy release. In this paper we calculate the rate of the relic antineutrino capture on holmium-163 nuclei against the corresponding EC decay rate by taking account of different neutrino mass hierarchies and reasonable values of theta_13. We show that such flavor effects are appreciable and even important in some cases, and stress that a calorimetric measurement of the cosmic antineutrino background might be feasible in the far future.Comment: 13 pages, 5 figures, revised version, accepted for publication in Phys. Lett.

Reviews

Europe In the Round CD‐ROM, Guildford, Vocational Technologies, 1994

CAHRS hrSpectrum (November - December 2005)

HRSpec04_12.pdf: 163 downloads, before Oct. 1, 2020