20 research outputs found

    Book Reviews

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    Basic Neurology. Ed. by J. Gilroy and P. L. Holliday. Pp. vii + 373. Illustrated. R27,90. London: Macmillan. 1982.The Pathology of the Heart. By E. G. J. Olsen. Pp. ix + 402. Illustrated. R91,85. London: Macmillan. 1982.Profile of Disease and Health Care in South Africa. By H. C. J. van Rensburg and A. Mans. Pp. xvii + 319. R29,50. Pretoria: Academica Press. 1982.Principles of Ambulatory Medicine. Ed. by L. R. Barker, J. R. Burton and P. D. Zieve. Pp. xiii + 1127. Illustrated. R78,-. Baltimore, Maryland: Williams & Wilkins. 1982.Topical Reviews in Accident Surgery, vol. 2. Ed. by N. Tubbs and P. S. London. Pp. ix +258. Illustrated. £18,50. London: Wright PSG.1982.Early Care of the Injured Patient. 3rd ed. Ed. by A. J. Wait, L. F. Peltier, B. A. Pruitt jun, D. D. Trunkey and R. F. Wilson. Pp. xv + 413. Illustrated. Philadelphia: W. B. Saunders. 1982.Current Pediatric Therapy. 10th ed. By S. S. Gellis and B. M. Kagan. Pp. xxxviii + 776. R94,25. Philadelphia: W. B. Saunders. 1982.Selected Techniques in Interventional Radiology,vol. 19 (Saunders Monographs in Clinical Radiology). By S. Kadir, S. L. Kaufman, K. H. Barth and R. 1. White jun. Pp. xi +216. Illustrated. R76,75. Philadelphia: W. B. Saunders. 1982.Clinical Topics in Internal Medicine. Ed. by G. M. Tisi and H. M. Ranney. Pp. xii 173. Illustrated. Baltimore, Maryland: Williams & Wilkins. 1982.Recognizable Patterns of Human Malformation: Genetic Embryologic and Clinical Aspects (Major Problems in Clinical Pediatrics, vo!. vii). 3rd ed. By W. David and M. D. Smith. Pp. xvii + 653. Illustrated. R78,55. Philadelphia: W. B. Saunders. 1982.The Patient and the Plastic Surgeon. By R. M. Goldwyn. Pp. xiii + 255. Boston: Little, Brown. 1981.The Aging Lumbar Spine. By S. W. Wiesel, P. Bernini and R. H. Rothman. Pp. 257. Illustrated. R69,55. Philadelphia: W. B. Saunders. 1982.Postoperative Complications of Intracranial Neurological Surgery. By N. H. Horwitz and H. V. Rizzoli. Pp. xi + 472. Illustrated. Baltimore: Williams & Wilkins. 1982.Current Topics in Inflammation and Infection (International Academy of Pathology Monograph). Ed. by G. Majno, R. S. Cotran and . Kaufman. Pp. xi + 242. Illustrated. Baltimore, Maryland: Williams & Wilkins. 1982.Radiology of the Ear, Nose and Throat. By G. E. Valvassori, G. D. Porter, W. N. Hanafee, B. L. Carter and R. A. Buckingham. Pp. viii + 342. Illustrated. RI94,30. Philadelphia: \Y/. B. Saunders. 1982.Neuropathology ofParasitic Infections. By W. J. Brown and M. Voge. Pp. 240. Illustrated. RI5,-. Oxford: Oxford Medical Publishers. 1982.Herzkrankheiten: Pathophysiologie, Diagoostik, Therapie. 2nd ed. By H. Roskamm and H. Reindel!. Pp. xxxiii + 1543. Illustrated. DM 278,-. Berlin: Springer-Verlag. 1982.Review ofSpeech, Language and Hearing, vols I, 2and 3. By N. J. Lass, L. V. McReynolds, J. L. Northern and D. E. Yoder. Illustrated. R36,20 each. Philadelphia: W. B. Saunders. 1982

    Research of the NUSTAR departments : SHE departments and HIM SHE section

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    The SHE departments devoted to the research of superheavy elements, operate the recoil separators SHIP and TASCA and their ancillary installations including SHIPTRAP and a laser spectroscopy setup at SHIP as well as chemistry and nuclear spectroscopy setups at TASCA. In 2019, the activities at GSI focused on the UNILAC beamtime within the FAIR Phase-0 program and on the analysis of data obtained in prior beamtimes. At HIM, the advancement of actinide sample preparation, manipulation, and characterization for various applications was most central. In addition, technical developments, for example for single-ion mass measurements, have been performed

    High-resolution and low-background 163^{163}Ho spectrum: interpretation of the resonance tails

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    The determination of the effective electron neutrino mass via kinematic analysis of beta and electron capture spectra is considered to be model-independent since it relies on energy and momentum conservation. At the same time the precise description of the expected spectrum goes beyond the simple phase space term. In particular for electron capture processes, many-body electron-electron interactions lead to additional structures besides the main resonances in calorimetrically measured spectra. A precise description of the 163^{163}Ho spectrum is fundamental for understanding the impact of low intensity structures at the endpoint region where a finite neutrino mass affects the shape most strongly. We present a low-background and high-energy resolution measurement of the 163^{163}Ho spectrum obtained in the framework of the ECHo experiment. We study the line shape of the main resonances and multiplets with intensities spanning three orders of magnitude. We discuss the need to introduce an asymmetric line shape contribution due to Auger–Meitner decay of states above the auto-ionisation threshold. With this we determine an enhancement of count rate at the endpoint region of about a factor of 2, which in turn leads to an equal reduction in the required exposure of the experiment to achieve a given sensitivity on the effective electron neutrino mass

    The electron capture in 163^{163}Ho experiment – ECHo

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    Neutrinos, and in particular their tiny but non-vanishing masses, can be considered one of the doors towards physics beyond the Standard Model. Precision measurements of the kinematics of weak interactions, in particular of the 3^{3}H β-decay and the 163^{163}Ho electron capture (EC), represent the only model independent approach to determine the absolute scale of neutrino masses. The electron capture in 163^{163}Ho experiment, ECHo, is designed to reach sub-eV sensitivity on the electron neutrino mass by means of the analysis of the calorimetrically measured electron capture spectrum of the nuclide 163^{163}Ho. The maximum energy available for this decay, about 2.8 keV, constrains the type of detectors that can be used. Arrays of low temperature metallic magnetic calorimeters (MMCs) are being developed to measure the 163^{163}Ho EC spectrum with energy resolution below 3 eV FWHM and with a time resolution below 1 μs. To achieve the sub-eV sensitivity on the electron neutrino mass, together with the detector optimization, the availability of large ultra-pure 163^{163}Ho samples, the identification and suppression of background sources as well as the precise parametrization of the 163^{163}Ho EC spectrum are of utmost importance. The high-energy resolution 163^{163}Ho spectra measured with the first MMC prototypes with ion-implanted 163^{163}Ho set the basis for the ECHo experiment. We describe the conceptual design of ECHo and motivate the strategies we have adopted to carry on the present medium scale experiment, ECHo-1K. In this experiment, the use of 1 kBq 163^{163}Ho will allow to reach a neutrino mass sensitivity below 10 eV/c2^{2}. We then discuss how the results being achieved in ECHo-1k will guide the design of the next stage of the ECHo experiment, ECHo-1M, where a source of the order of 1 MBq 163^{163}Ho embedded in large MMCs arrays will allow to reach sub-eV sensitivity on the electron neutrino mass

    Nuclear Structure Investigations of Es 253-255 by Laser Spectroscopy

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    Laser resonance ionization spectroscopy was performed on the rare einsteinium isotopes Es253-255 at the RISIKO mass separator in Mainz. With low sample sizes ranging down to femtograms, the prominent 352 nm-ground-state transition was measured in all three einsteinium isotopes, and four additional ground-state transitions were measured in Es254. Hyperfine-structure analysis resulted in assigned spin values of I(Es254)=7 and I(Es255)=7/2. From the extracted coupling constants, nuclear magnetic dipole moments of μI(Es254)=3.42(7)μN and μI(Es255)=4.14(10)μN as well as spectroscopic electric quadrupole moments of Qs(Es254)=9.6(1.2)eb and Qs(Es255)=5.1(1.7)eb were derived. Our value for Es254 deviates from the value of |μI(Es254)|=4.35(41)μN extracted from the angular anisotropy of α-radiation emitted by Es254. © 2022 authors. Published by the American Physical Society.Acknowledgments. This research was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Heavy Elements Chemistry Program, under Award DE-FG02-13ER16414. The isotopes used in this research were supplied by the U.S. DOE Isotope Program, managed by the Office of Science. This work has been supported by the Bundesministerium für Bildung und Forschung (BMBF, Germany) under Project No. 05P18UMCIA. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 861198–LISA–H2020-MSCA-ITN-2019

    A White Paper on keV Sterile Neutrino Dark Matter

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    We present a comprehensive review of keV-scale sterile neutrino Dark Matter,collecting views and insights from all disciplines involved - cosmology,astrophysics, nuclear, and particle physics - in each case viewed from boththeoretical and experimental/observational perspectives. After reviewing therole of active neutrinos in particle physics, astrophysics, and cosmology, wefocus on sterile neutrinos in the context of the Dark Matter puzzle. Here, wefirst review the physics motivation for sterile neutrino Dark Matter, based onchallenges and tensions in purely cold Dark Matter scenarios. We then round outthe discussion by critically summarizing all known constraints on sterileneutrino Dark Matter arising from astrophysical observations, laboratoryexperiments, and theoretical considerations. In this context, we provide abalanced discourse on the possibly positive signal from X-ray observations.Another focus of the paper concerns the construction of particle physicsmodels, aiming to explain how sterile neutrinos of keV-scale masses could arisein concrete settings beyond the Standard Model of elementary particle physics.The paper ends with an extensive review of current and future astrophysical andlaboratory searches, highlighting new ideas and their experimental challenges,as well as future perspectives for the discovery of sterile neutrinos

    A White Paper on keV sterile neutrino Dark Matter

    Get PDF
    We present a comprehensive review of keV-scale sterile neutrino Dark Matter, collecting views and insights from all disciplines involved—cosmology, astrophysics, nuclear, and particle physics—in each case viewed from both theoretical and experimental/observational perspectives. After reviewing the role of active neutrinos in particle physics, astrophysics, and cosmology, we focus on sterile neutrinos in the context of the Dark Matter puzzle. Here, we first review the physics motivation for sterile neutrino Dark Matter, based on challenges and tensions in purely cold Dark Matter scenarios. We then round out the discussion by critically summarizing all known constraints on sterile neutrino Dark Matter arising from astrophysical observations, laboratory experiments, and theoretical considerations. In this context, we provide a balanced discourse on the possibly positive signal from X-ray observations. Another focus of the paper concerns the construction of particle physics models, aiming to explain how sterile neutrinos of keV-scale masses could arise in concrete settings beyond the Standard Model of elementary particle physics. The paper ends with an extensive review of current and future astrophysical and laboratory searches, highlighting new ideas and their experimental challenges, as well as future perspectives for the discovery of sterile neutrinos

    The electron capture in 163Ho experiment – ECHo

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    Metallic magnetic calorimeter arrays for the first phase of the ECHo experiment

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    The ECHo experiment has been designed for the determination of the effective electron neutrino mass by means of the analysis of the end-point region of the Ho-163 electron capture spectrum. Metallic magnetic calorimeters enclosing Ho-163 are used for the high energy resolution calorimetric measurement of the Ho-163 spectrum. For the first phase of the experiment, ECHo-1k, a 72-pixel MMC array has been developed. The single-pixel design has been optimised to reach 100% stopping power for the radiation emitted in the Ho-163 electron capture process (besides the electron neutrino) and an energy resolution . We describe the design of the ECHo-1k detector chip, the fabrication steps and the characterisation at room temperature, at 4 K and at the final operation temperatures. In particular, a detailed analysis of the results from these tests allowed to define a quality check protocol based on parameters measurable at room temperature. We discuss the performance achieved with the two ECHo-1k detector chips – the first one with 163Ho implanted in gold and the second one with Ho-163 implanted in silver – which have been used for the high statistics measurement of the ECHo-1k experiment. An average activity per pixel of and and an average energy resolution of FWHM and FWHM have been achieved with these two detectors, fulfilling the requirements for the first phase of the ECHo experiment
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