Author: Axel Reimer MüllerPublisher:
ISBN:
Category :
Languages : en
Pages : 210
Book Description
Characterization of Solid D_1tn2 as Source Material for Ultra Cold Neutrons and Development of a Detector Concept for the Detection of Protons from the Neutron Decay
Author: Axel Reimer MüllerUse of Ultracold Neutrons for Condensed-matter Studies
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 69
Book Description
Ultracold neutrons have such low velocities that they are reflected by most materials at all incident angles and can be stored in material bottles for long periods of time during which their intrinsic properties can be studied in great detail. These features have been mainly used for fundamental-physics studies including the detection of a possible neutron electric dipole moment and the precise determination of neutron-decay properties. Ultracold neutrons can also play a role in condensed-matter studies with the help of high-resolution spectrometers that use gravity as a strongly dispersive medium for low-velocity neutrons. Such studies have so far been limited by the low intensity of existing ultracold-neutron sources but could be reconsidered with more intense sources, which are now envisaged. This report provides a broad survey of the properties of ultracold neutrons (including their reflectivity by different types of samples), of ultracold-neutron spectrometers that are compared with other high-resolution instruments, of results obtained in the field of condensed matter with these instruments, and of neutron microscopes. All these subjects are illustrated by numerous examples.
Characterization of Solid Deuterium Ultracold Neutron Source Production and UCN Transport
Author: Yanping XuPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Keywords: ucn transport, depolarization, ultracold neutron source.
Characterization of a Solid Deuterium Converter for Ultra-cold Neutrons (UCN) in the Framework of the Mini-D 2 Project at the FRM-II Reactor in Munich
Author: Daniele TortorellaStudies of Solid-deuterium Source of Ultracold Neutrons and Hydrogen- Deuterium Mixtures for Cold Neutron Sources
Author: A. P. SerebrovMaterials Research Using Cold Neutrons at Pulsed Neutron Sources
Author: P. ThiyagarajanPublisher: World Scientific Publishing Company Incorporated
ISBN: 9789810237486
Category : Science
Languages : en
Pages : 221
Book Description
The applications of the use of cold neutrons for condensed matter research at accelerator-based spallation sources are less well-known than that of the use of cold neutrons at reactor sources. This book represents the outcome of the first international workshop on “Materials Research Using Cold Neutrons at Pulsed Sources”. It consists of overviews of the present status and future trends in research opportunities using cold neutrons, as well as topical papers focusing on the areas of small-angle neutron scattering, reflectivity and spectroscopic studies of a rich variety of materials, from adsorbed molecules to thin films to coal to metallic glasses. These papers will benefit researchers who are interested in the characterization of microscopic properties of advanced materials.
Detecting High Rates of Ultracold Neutrons and Thermal Neutron Production
Author: Lori RebenitschPublisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
The first phase of the TRIUMF ultracold advanced neutron source (TUCAN) is operational at TRIUMF in Vancouver, Canada, with the second phase scheduled to be completed in 2020. The first proposed experiment with the source is a neutron electric dipole moment (nEDM) measurement. Preparing the experiment requires building the nEDM experimental cell, containing high voltage, magnetic fields, $B_0$ and $B_1$ coils, magnetic shielding to run the Ramsey cycle; a prototype detection system; and commissioning the TUCAN source. This thesis focuses on measurements that characterize the prototype UCN counter, as well as the thermal neutron flux measurement around TUCAN, as part of the source commissioning. The UCN counter is a \ce{^6Li}-doped glass detector, designed for high rates of UCN. The detector efficiency is comparable to the GEM-based Cascade-U detector at the UCN source at the Paul Scherrer Institute. Comparing the \ce{^6Li} detector to simulation gave a neutron efficiency of $99.5 \pm 0.5$~\% with a background contamination of $0.3 \pm 0.1$~\%. The total efficiency of this detector was measured to be $89.7^{+1.3}_{-1.9}$~\%. The thermal neutron measurement used Au and Cd-covered Au foils to measure the thermal and colder neutron flux around TUCAN at different temperatures. This measurement was conducted at TRIUMF during the initial commissioning of neutron production. There were some large discrepancies between the measured data and simulation and also between measurements with the same settings. A number of discrepancies were found to be due to differences between the experimental set up and the model. Modeling graphite, in particular, is limited due to the wide variability of the structure of graphite and is known to vary up to 40\% from the measurement depending on structural factors. The largest discrepancy was due to difficulties in steering the proton beam onto the tungsten target. However, none of the simulated effects were large enough to cover the measured results, suggesting there was a systematic effect that was not well-understood. While thermal and colder neutron flux was measured, the amount varied too much from irradiation run to irradiation run to determine the flux with consistency.
Essentials of Chemical Biology
Author: Andrew D. MillerPublisher: John Wiley & Sons
ISBN: 1118687833
Category : Science
Languages : en
Pages : 620
Book Description
"This excellent work fills the need for an upper-level graduate course resource that examines the latest biochemical, biophysical, and molecular biological methods for analyzing the structures and physical properties of biomolecules... This reviewer showed [the book] to several of his senior graduate students, and they unanimously gave the book rave reviews. Summing Up: Highly recommended..." CHOICE Chemical biology is a rapidly developing branch of chemistry, which sets out to understand the way biology works at the molecular level. Fundamental to chemical biology is a detailed understanding of the syntheses, structures and behaviours of biological macromolecules and macromolecular lipid assemblies that together represent the primary constituents of all cells and all organisms. The subject area of chemical biology bridges many different disciplines and is fast becoming an integral part of academic and commercial research. This textbook is designed specifically as a key teaching resource for chemical biology that is intended to build on foundations lain down by introductory physical and organic chemistry courses. This book is an invaluable text for advanced undergraduates taking biological, bioorganic, organic and structural chemistry courses. It is also of interest to biochemists and molecular biologists, as well as professionals within the medical and pharmaceutical industry. Key Features: A comprehensive introduction to this dynamic area of chemistry, which will equip chemists for the task of understanding and studying the underlying principles behind the functioning of biological macro molecules, macromolecular lipid assemblies and cells. Covers many basic concepts and ideas associated with the study of the interface between chemistry and biology. Includes pedagogical features such as: key examples, glossary of equations, further reading and links to websites. Clearly written and richly illustrated in full colour.
Materials Research Using Cold Neutrons at Pulsed Neutron Sources
Author: Chun Keung LoongPublisher:
ISBN: 9789814527750
Category : Cold neutrons
Languages : en
Pages : 245
Book Description
Development of an Ultra Cold Neutron Source at MLNSC.
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 6
Book Description
Ultra Cold Neutrons (UCN) can be produced at spallation sources using a variety of techniques. To date the technique used has been to Bragg scatter and Doppler shift cold neutrons into UCN from a moving crystal. This is particularly applicable to short-pulse spallation sources. We are presently constructing a UCN source at LANSCE using this method. In addition, large gains in UCN density should be possible using cryogenic UCN sources. Research is under way at Gatchina to demonstrate technical feasibility of a frozen deuterium source. If successful, a source of this type could be implemented at future spallation sources, such as the long pulse source being planned at Los Alamos, with a UCN density that may be two orders of magnitude higher than that presently available at reactors.