Alpha Backgrounds and Their Implications for Neutrinoless Double-beta Decay Experiments Using HPGe Detectors PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Alpha Backgrounds and Their Implications for Neutrinoless Double-beta Decay Experiments Using HPGe Detectors PDF full book. Access full book title Alpha Backgrounds and Their Implications for Neutrinoless Double-beta Decay Experiments Using HPGe Detectors by Robert A. Johnson. Download full books in PDF and EPUB format.
Author: Robert A. Johnson
Publisher:
ISBN:
Category : Double beta decay
Languages : en
Pages : 143
Get Book Here
Book Description
Author: Robert A. Johnson
Publisher:
ISBN:
Category : Double beta decay
Languages : en
Pages : 143
Get Book Here
Book Description
Author: Julieta Gruszko
Publisher:
ISBN:
Category :
Languages : en
Pages : 178
Get Book Here
Book Description
Though the existence of neutrino oscillations proves that neutrinos must have non-zero mass, Beyond-the-Standard-Model physics is needed to explain the origins of that mass. One intriguing possibility is that neutrinos are Majorana particles, i.e., they are their own anti-particles. Such a mechanism could naturally explain the observed smallness of the neutrino masses, and would have consequences that go far beyond neutrino physics, with implications for Grand Unification and leptogenesis. If neutrinos are Majorana particles, they could undergo neutrinoless double-beta decay (0nBB), a hypothesized rare decay in which two antineutrinos annihilate one another. This process, if it exists, would be exceedingly rare, with a half-life over 1E25 years. Therefore, searching for it requires experiments with extremely low background rates. One promising technique in the search for 0nBB is the use of P-type point-contact (P-PC) high-purity Germanium (HPGe) detectors enriched in 76Ge, operated in large low-background arrays. This approach is used, with some key differences, by the MAJORANA and GERDA Collaborations. A problematic background in such large granular detector arrays is posed by alpha particles incident on the surfaces of the detectors, often caused by 222Rn contamination of parts or of the detectors themselves. In the MAJORANA DEMONSTRATOR, events have been observed that are consistent with energy-degraded alphas originating near the passivated surface of the detectors, leading to a potential background contribution in the region-of-interest for neutrinoless double-beta decay. However, it is also observed that when energy deposition occurs very close to the passivated surface, high charge trapping occurs along with subsequent slow charge re-release. This leads to both a reduced prompt signal and a measurable change in slope of the tail of a recorded pulse. Here we discuss the characteristics of these events and the development of a filter that can identify the occurrence of this delayed charge recovery (DCR) effect, allowing for the efficient rejection of passivated surface alpha events in analysis. Using a dedicated test-stand called the TUM Upside-down BEGe (TUBE) scanner, we have characterized the response of a P-PC detector like those used in the DEMONSTRATOR to alphas incident on the sensitive surfaces, developing a model for the radial dependence of the energy loss to charge trapping and determining the dominant mechanism behind the delayed charge effect. We have also used these measurements to demonstrate the complementarity of the DCR analysis with the drift-time analysis that is used to identify alpha background candidate events in the GERDA detectors. Using these two methods, we demonstrate the ability to effectively reject all alpha events (to within statistical uncertainty) with only 0.2% bulk event sacrifice. Applying the DCR analysis to the events observed in the MAJORANA DEMONSTRATOR, we find that it reduces the backgrounds in the 0nBB region-of-interest by a factor of 29, increasing the expected experimental sensitivity by a factor of 3 over the lifetime of the DEMONSTRATOR. The results of the dedicated measurements in the TUBE scanner can be used to build a background model for alpha decays in the DEMONSTRATOR; here, we examine two simplified geometric models for the alpha source distribution and find that the observed spectral shape is consistent with alpha events originating in the plastics of the detector units.
Author: Michael F. L'Annunziata
Publisher: Academic Press
ISBN: 0128143967
Category : Science
Languages : en
Pages : 1076
Get Book Here
Book Description
Handbook of Radioactivity Analysis: Radiation Physics and Detectors, Volume One, and Radioanalytical Applications, Volume Two, Fourth Edition, constitute an authoritative reference on the principles, practical techniques and procedures for the accurate measurement of radioactivity - everything from the very low levels encountered in the environment, to higher levels measured in radioisotope research, clinical laboratories, biological sciences, radionuclide standardization, nuclear medicine, nuclear power, and fuel cycle facilities, and in the implementation of nuclear forensic analysis and nuclear safeguards. It includes sample preparation techniques for all types of matrices found in the environment, including soil, water, air, plant matter and animal tissue, and surface swipes.Users will find the latest advances in the applications of radioactivity analysis across various fields, including environmental monitoring, radiochemical standardization, high-resolution beta imaging, automated radiochemical separation, nuclear forensics, and more. Spans two volumes, Radiation Physics and Detectors and Radioanalytical Applications Includes a new chapter on the analysis of environmental radionuclides Provides the latest advances in the applications of liquid and solid scintillation analysis, alpha- and gamma spectrometry, mass spectrometric analysis, Cherenkov counting, flow-cell radionuclide analysis, radionuclide standardization, aerosol analysis, high-resolution beta imaging techniques, analytical techniques in nuclear forensics, and nuclear safeguards Describes the timesaving techniques of computer-controlled automatic separation and activity analysis of radionuclides Provides an extensive table of the radiation characteristics of most radionuclides of interest for the radioanalytical chemist
Author: Joseph Mario Krivicich
Publisher:
ISBN:
Category :
Languages : en
Pages : 248
Get Book Here
Book Description
Author: Pavel P. Povinec
Publisher: Elsevier
ISBN: 0080553370
Category : Medical
Languages : en
Pages : 539
Get Book Here
Book Description
The purpose of this book is to present a state of art summary of current knowledge of methods of assessment of radionuclides in the terrestrial and marine environments. It cover the traditional methods of radioactivity measurements such as radiometrics techniques, but also recent developments in the mass spectrometry sector. The book starts with a short preface introducing the subject of the book, summarising content and philosophy of the book, as well as the most important historical achievements. The scientific topics are introduced by description of sampling methods, optimisation of sampling sites and sampling frequency. The recent developments in radiochemical separation methods using chromatography resins for the treatment of actinides, transuranics and other groups of radioelements are also described. No other book is available covering all aspects of environmental radioactivity measurements, although remarkable progress has been made in detection techniques over the last ten years. At present the new methods enable to carry out investigations which were not possible before, either because of lack of sensitivity or because of the fact that they required too large samples.
Author: Matteo Agostini
Publisher:
ISBN:
Category :
Languages : en
Pages : 161
Get Book Here
Book Description
Author: Andrea Lazzaro
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Author: Michael F. L'Annunziata
Publisher: Elsevier
ISBN: 0323137881
Category : Science
Languages : en
Pages : 810
Get Book Here
Book Description
Handbook of Radioactivity Analysis is written by experts in the measurement of radioactivity. The book describes the broad scope of analytical methods available and instructs the reader on how to select the proper technique. It is intended as a practical manual for research which requires the accurate measurement of radioactivity at all levels, from the low levels encountered in the environment to the high levels measured in radioisotope research. This book contains sample preparation procedures, recommendations on steps to follow, necessary calculations, computer controlled analysis, and high sample throughput techniques. Each chapter includes practical techniques for application to nuclear safety, nuclear safeguards, environmental analysis, weapons disarmament, and assays required for research in biomedicine and agriculture. The fundamentals of radioactivity properties, radionuclide decay, and methods of detection are included to provide the basis for a thorough understanding of the analytical procedures described in the book. Therefore, the Handbook can also be used as a teaching text. Includes sample preparation techniques for matrices such as soil, air, plant, water, animal tissue, and surface swipes Provides procedures and guidelines for the analysis of commonly encountered na
Author: Ann-Kathrin Schütz
Publisher:
ISBN:
Category : Double beta decay
Languages : en
Pages :
Get Book Here
Book Description
Author: R. Ito
Publisher:
ISBN:
Category :
Languages : en
Pages : 11
Get Book Here
Book Description
