Infrared phonons and specific heat in Ba3Cr2O8

We report on the phonon spectrum of Ba3Cr2O8 determined by infrared spectroscopy, and on specific heat measurements across the Jahn-Teller transition in magnetic fields up to 9 T. Phonon modes split below the Jahn-Teller transition, which occurs at T_{JT} = 70 K as detected by specific heat measurements. The field-dependent specific heat data is analyzed in terms of the contributions from lattice, magnetic and orbital degrees of freedom. In contrast to the isostructural compound Sr3Cr2O8 our analysis does not indicate the existence of orbital fluctuations below the Jahn-Teller transition in Ba3Cr2O8.Comment: 5 pages, 4 figure

MetroMMC: Electron-Capture Spectrometry with Cryogenic Calorimeters for Science and Technology

Accurate decay data of radionuclides are necessary for many fields of science and technology, ranging from medicine and particle physics to metrology. However, data that are in use today are mostly based on measurements or theoretical calculation methods that are rather old. Recent measurements with cryogenic detectors and other methods show significant discrepancies to both older experimental data and theory in some cases. Moreover, the old results often suffer from large or underestimated uncertainties. This is in particular the case for electron-capture (EC) decays, where only a few selected radionuclides have ever been measured. To systematically address these shortcomings, the European metrology project MetroMMC aims at investigating six radionuclides decaying by EC. The nuclides are chosen to cover a wide range of atomic numbers Z, which results in a wide range of decay energies and includes different decay modes, such as pure EC or EC accompanied by γ- and/or β+-transitions. These will be measured using metallic magnetic calorimeters (MMCs), cryogenic energy-dispersive detectors with high-energy resolution, low-energy threshold and high, adjustable stopping power that are well suited for measurements of the total decay energy and X-ray spectrometry. Within the MetroMMC project, these detectors are used to obtain X-ray emission intensities of external sources as well as fractional EC probabilities of sources embedded in a 4 π absorber. Experimentally determined nuclear and atomic data will be compared to state-of-the-art theoretical calculations which will be further developed within the project. This contribution introduces the MetroMMC project and in particular its experimental approach. The challenges in EC spectrometry are to adapt the detectors and the source preparation to the different decay channels and the wide energy range involved, while keeping the good resolution and especially the low-energy threshold to measure the EC from outer shells. © 2019, The Author(s)

Development of 100^{100}Mo-containing scintillating bolometers for a high-sensitivity neutrinoless double-beta decay search

We report recent achievements in the development of scintillating bolometers to search for neutrinoless double-beta decay of $^{100}$Mo. The presented results have been obtained in the framework of the LUMINEU, LUCIFER and EDELWEISS collaborations, and are now part of the R\&D activities towards CUPID (CUORE Update with Particle IDentification), a proposed next-generation double-beta decay experiment based on the CUORE experience. We have developed a technology for the production of large mass ($\sim$1 kg), high optical quality, radiopure zinc and lithium molybdate crystal scintillators (ZnMoO$_4$ and Li$_2$MoO$_4$, respectively) from deeply purified natural and $^{100}$Mo-enriched molybdenum. The procedure is applied for a routine production of enriched crystals. Furthermore, the technology of a single detector module consisting of a large-volume ($\sim 100$~cm$^3$) Zn$^{100}$MoO$_4$ and Li$_2$$^{100}$MoO$_4$ scintillating bolometer has been established, demonstrating performance and radiopurity that are close to satisfy the demands of CUPID. In particular, the FWHM energy resolution of the detectors at 2615 keV --- near the $Q$-value of the double-beta transition of $^{100}$Mo (3034~keV) --- is $\approx$ 4--10~keV. The achieved rejection of $\alpha$-induced dominant background above 2.6~MeV is at the level of more than 99.9\%. The bulk activity of $^{232}$Th ($^{228}$Th) and $^{226}$Ra in the crystals is below 10 $\mu$Bq/kg. Both crystallization and detector technologies favor Li$_2$MoO$_4$, which was selected as a main element for the realization of a CUPID demonstrator (CUPID-0/Mo) with $\sim$7 kg of $^{100}$Mo

Verwendung einer Waffe beim Raub

Die Begehung eines Raubes (§ 142 StGB) ist bei Verwendung einer Waffe als schwerer Raub (§ 143 Abs 1 2. Fall StGB) qualifiziert. Die gesetzliche Umschreibung der Qualifizierung des bewaffneten Raubes stellt allein auf eine „Waffe“ ab, während bei ähnlich qualifizierenden Tatbeständen (bspw Diebstahl mit Waffen § 129 Abs 2 Z 2 StGB) den „Waffen“ auch andere Mittel gleichgestellt werden. Vor diesem Hintergrund haben sich zum Waffenbegriff verschiedene Sichtweisen herausgebildet.Die Rechtsprechung hat schlussendlich einem funktionellen Begriffsverständnis den Vorzug gegeben. Danach sind vom Waffenbegriff grundsätzlich alle Waffen nach dem Waffengesetz erfasst (Kernbereich), darüber hinaus auch Gegenstände die hinsichtlich Anwendbarkeit, Wirkung und Form den Waffen iSd WaffG gleichzuhalten sind. Trotz dieses funktionellen Ansatzes sind auch funktionsuntüchtige Waffen anders als bloße Scheinwaffen vom Waffenbegriff umfasst. Der OGH versteht auch das „Verwenden“ einer Waffe funktionell: Sie kann auf beliebige Art und Weise benützt worden sein, solange sie bei der Tat kausal zum Einsatz gekommen ist.A robbery (Section 142 of the Austrian Criminal Code [StGB]) is qualified as an aggravated robbery (Section 143 Paragraph 1 2nd case StGB) in case a weapon is used. The legal description of the qualification of armed robbery is restricted to the term "weapon", whereas in comparable offences, like theft with weapons (Section 129 Paragraph 2 no. 2 StGB) also other means which can be equated to "weapons" are covered. This leads to uncertainties in the understanding of the term “weapon”, which is why several legal opinions regarding the issue evolved. Court decisions have ultimately given preference to a functional understanding of the term. Thus the concept of weapons includes all arms defined in the Austrian Arms Act [WaffG] (core section), as well as objects that are equivalent to weapons in terms of their applicability, effect and shape pursuant to the WaffG. Beyond this functional approach inoperative weapons - unlike mere sham weapons - are included in the term weapon. The Supreme Court of Justice (OGH) also interprets the “use” of a weapon in a functional sense: It states that a weapon can be used in any way as long there is a causal relationship between the “use” of a weapon and the criminal act.Arbeit an der Bibliothek noch nicht eingelangt - Daten nicht geprüftAbweichender Titel laut Übersetzung des Verfassers/der VerfasserinKarl-Franzens-Universität Graz, Diplomarbeit, 2020(VLID)509632

Determination of fractional electron capture probabilities using Metallic Magnetic Calorimeters

International audienceThe measurements are the part of the European metrology research project MetroMMC, which started in 2018 for a duration of 3 years. This project concerns the development and use of MMC detectors and complementary detection techniques to understand the electron capture (EC) process in the decay and subsequent atomic relaxation processes in a few selected atomic nuclei. The goals of MetroMMC include:• Measurement of fractional electron capture probabilities and absolute X-ray emission intensities.• To improve theoretical models and calculations of the electron capture process and subsequent atomic relaxation.• Validation of the theoretical data with the high-precision experimental data from this project.• Six radionuclides that decay by EC have been selected for measurement within the project: Ca-41, Mn-54, Ni-59, Zn-65, Cd-109 and I-125