Download or read book New Technique for Barium Daughter Ion Identification in a Liquid Xe 136 Double Beta Decay Experiment written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This work addresses long-standing issues of fundamental interest in elementary particle physics. The most important outcome of this work is a new limit on neutrinoless double beta decay. This is an extremely rare and long sought after type of radioactive decay. If discovered, it would require changes in the standard model of the elementary constituents of matter, and would prove that neutrinos and antineutrinos are the same, a revolutionary concept in particle physics. Neutrinos are major components of the matter in the universe that are so small and so weakly interacting with other matter that their masses have not yet been discovered. A discovery of neutrinoless double beta decay could help determine the neutrino masses. An important outcome of the work on this project was the Colorado State University role in operating the EXO-200 neutrinoless double beta decay experiment and in analysis of the data from this experiment. One type of double beta decay of the isotope 136Xe, the two-neutrino variety, was discovered in this work. Although the other type of double beta decay, the neutrinoless variety, was not yet discovered in this work, a world's best sensitivity of 1.9x1025 year half-life was obtained. This result rules out a previous claim of a positive result in a different isotope. This work also establishes that the masses of the neutrinos, are less than one millionth of that of electrons. A unique EXO-200 analysis, in which the CSU group had a leading role, has established for the first time ever in a liquid noble gas the fraction of daughter atoms from alpha and beta decay that are ionized. This result has important impact on other pending studies, including nucleon decay and barium tagging. Novel additional discoveries include multiphoton ionization of liquid xenon with UV pulsed lasers, which may find application in calibration of future noble liquid detectors, and studies of association and dissociation reactions of Ba+ ions in gaseous xenon. Through this project, we are substantially closer to demonstrating "barium tagging", i.e., detection of single daughter 136Ba atoms from 136Xe double beta decay. Milestones achieved include obtaining spectra of small numbers of Ba atoms and cryoprobe advances toward trapping single 136Ba atoms in solid xenon and probe extraction for detection. One of the other benefits to society is the training of six Ph. D. students in a variety of state-of-the-art technologies, half under primary support of this grant and half with partial support, with four finishing their Ph. D. degrees and two well on their way.

Download or read book Surface Adsorption and Resonance Ionization Spectroscopy for Barium Identification in Neutrinoless Double Beta Decay Experiments written by Karl Twelker and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Neutrinos are the only elementary particle that could have particle-antiparticle duality, called Majorana nature. If neutrinos do indeed have this property, it could be measured through neutrinoless double-beta decay, a hypothetical nuclear decay. The half-life of this decay is very long, thus the reduction of backgrounds is very important. In searches for neutrinoless double-beta decay in Xe-136, backgrounds in the signal region of interest can be eliminated by recovering the expected daughter nucleus of this decay, Ba-136. This work describes the development of a technique to recover these barium ions from liquid xenon using surface adsorption and identify them using Resonance Ionization Spectroscopy (RIS). Barium ions adsorb onto a surface in the liquid xenon, which we remove to a separate vacuum chamber for identification. Laser induced thermal desorption removes atoms from the surface into vacuum, then the barium is re-ionized using RIS and drifted down a time of flight mass spectrometer. RIS has been shown to be both efficient and selective, both favorable aspects for a barium tagging system. The prototype system described here offers both optical spectroscopic and mass spectroscopic confirmation of the barium daughter. Barium tagging is being developed for use in nEXO, a future neutrinoless double-beta decay experiment, and will allow the detector to probe into the normal hierarchy of neutrino masses.

Download or read book Searching for Double Beta Decay with the Enriched Xenon Observatory written by and published by . This book was released on 2007 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Enriched Xenon Observatory (EXO) Collaboration is building a series of experiments to search for the neutrinoless double beta decay of 136Xe. The first experiment, known as EXO-200, will utilize 200 kg of xenon enriched to 80% in the isotope of interest, making it the largest double beta decay experiment to date by one order of magnitude. This experiment is rapidly being constructed, and will begin data taking in 2007. The EXO collaboration is also developing a technique to identify on an event-by-event basis the daughter barium ion of the double beta decay. If successful, this method would eliminate all conventional radioactive backgrounds to the decay, resulting in an ideal experiment. We summarize here the current status of EXO-200 construction and the barium tag R & D program.

Download or read book On Ion Probes and Traps written by Matthew Piron Green and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Enriched Xenon Observatory seeks to measure neutrino mass through observation of neutrinoless double beta decay. A new generation of ton-scale experiments are being developed, which aim to probe neutrinoless double beta decay half-lives on the order of 10^27 - 10^28 years. The keys to reaching these sensitivities are large source mass and reduction of radioactive backgrounds; this thesis details efforts to develop a system for tagging the 136-Ba+ daughter of the double beta decay of 136-Xe, for the purposes of background elimination in a large experiment.

Download or read book Detecting the Barium Daughter in 136Xe 0 Decay Using Single molecule Fluorescence Imaging Techniques written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Single-molecule fluorescent imaging may provide an avenue to efficiently detect the Ba ++ daughter atom in the decay 136 Xe → Ba + 2e −, and, unambiguously associate the birth point in space within the electron trajectories of the decay event. Chelation of doubly-charged alkaline earth elements such as calcium and barium by certain precursor molecules converts the resulting complex from a non-fluorescent to a fluorescent state. Repeated photo-excitation of a single fluorescent complex reveals both presence and location with high precision. This technique, widespread now in biochemistry, biophysics and biology, may permit a similar discriminating response in a large high-pressure xenon gas TPC for the Ba ++ ion from xenon double-beta decay. The TPC measures the event time and energy of the two nascent electrons, as well as topology and position in 3-D from their trajectories in the gas. Measurement of the 2-D location of the molecular ion after arrival at the cathode plane permits an association of ion with the event. Demonstration of an efficient, highly specific detection of the barium daughter would provide a long-sought pathway to a background-free result in the search for this decay mode, of central importance for determining the nature of the neutrino.

Download or read book Development of an In Xe gas Laser Ablation Source for the Ba tagging Technique for NEXO written by Melissa Medina Peregrina and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "nEXO is a next generation experiment searching for neutrinoless double beta decay in the isotope Xe-136. An observation of this decay would imply lepton number violation and require the neutrino to be its own antiparticle. Such an observation would demonstrate physics beyond the Standard Model of particle physics and alter our understanding of the universe.To increase nEXO's sensitivity in a future upgrade and to verify a potential signal as originating from true double decay events, the collaboration is developing a Ba-tagging technique with the aim of identifying the Xe-136 decay daughter Ba-136. In this scheme, the decay volume is probed for the presence of Ba when a candidate neutrinoless double beta decay event is detected. Since Ba-136 is only produced in double beta decays, the event can be identified as a double beta decay of Xe-136 and backgrounds can be discarded.The nEXO collaboration is investigating different approaches to extract and identify single barium ions. In Canada, groups at Carleton, McGill, and TRIUMF are working on extracting ions from liquid Xe into a gaseous environment and subsequently into vacuum for final identification of the barium ion. The group at McGill University is developing a laser ablation ion source to be operated in high pressure Xe-gas. This ablation source is intended to provide ions to study and optimize the ion extraction process. This thesis describes the setup, an analysis of the measured ion current in vacuum as function of different physical parameters along with future plans for this ion source. All in-gas measurements were interrupted because of COVID-19 and had to be postponed until after this MSc thesis"--

Download or read book Seventy Years Of Double Beta Decay From Nuclear Physics To Beyond standard model Particle Physics written by Hans Volker Klapdor-kleingrothaus and published by World Scientific. This book was released on 2010-03-25 with total page 1559 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the last 20 years the disciplines of particle physics, astrophysics, nuclear physics and cosmology have grown together in an unprecedented way. A brilliant example is nuclear double beta decay, an extremely rare radioactive decay mode, which is one of the most exciting and important fields of research in particle physics at present and the flagship of non-accelerator particle physics.While already discussed in the 1930s, only in the 1980s was it understood that neutrinoless double beta decay can yield information on the Majorana mass of the neutrino, which has an impact on the structure of space-time. Today, double beta decay is indispensable for solving the problem of the neutrino mass spectrum and the structure of the neutrino mass matrix. The potential of double beta decay has also been extended such that it is now one of the most promising tools for probing beyond-the-standard-model particle physics, and gives access to energy scales beyond the potential of future accelerators.This book presents the breathtaking manner in which achievements in particle physics have been made from a nuclear physics process. Consisting of a 150-page highly factual overview of the field of double beta decay and a 1200-page collection of the most important original articles, the book outlines the development of double beta decay research — theoretical and experimental — from its humble beginnings until its most recent achievements, with its revolutionary consequences for the theory of particle physics. It further presents an outlook on the exciting future of the field.

Download or read book A Search for Double Beta Decay of Xenon to Excited States of Barium with EXO 200 written by Sereres Johnston and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents searches for several modes of double beta decays of 136Xe to two low-lying excited levels of 136Ba. For each final level, both 2[nu] and 0[nu] double beta decay processes are considered. The data and general techniques developed by the EXO-200 collaboration are used, including a Machine Learning process to improve sensitivity in multivariate space. EXO-200 is an experimental program searching for 0[nu][beta][beta] decay in a time projection chamber filled with 175 kg of liquid Xenon enriched to 80% 136Xe, functioning as both source and detector. Experimental searches of double beta decay with 136Xe and other isotopes are motivated by non Standard Model neutrinoless decay (0[nu][beta][beta]) possibilities. If found this would imply the Majorana nature of neutrinos, provide access to the currently unknown absolute mass scale of the neutrino, and violate lepton conservation by 2 units. Nuclear matrix elements necessary to connecting observed neutrinoless halflife to the neutrino mass scale depend on nuclear models. Observation of both the 2[nu] 0+ excited and 0+ ground state in a single element may constrain these models. Sensitivity studies of search performance are described, and final sensitivities from 7.86 · 10^23 years to 2.00 · 10^25 years are reported.

Download or read book Double Beta decay written by Rolf G. Winter and published by . This book was released on 1951 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Emission Detectors written by Alexander I Bolozdynya and published by World Scientific. This book was released on 2010-07-30 with total page 223 pages. Available in PDF, EPUB and Kindle. Book excerpt: After decades of research and development, emission detectors have recently become the most successful instrumentation used in modern fundamental experiments searching for cold dark matter, and are also considered for neutrino coherent scattering and magnetic momentum neutrino measurement. This book is the first monograph exclusively dedicated to emission detectors. Properties of two-phase working media based on noble gases, saturated hydrocarbon, ion crystals and semiconductors are reviewed.

Download or read book Double Beta Decay in 136Xe written by Roland Lüscher and published by . This book was released on 1999 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Aspects of the R D for the Enriched Xenon Observatory for Double Beta Decay written by Kolo Wamba and published by . This book was released on 2006 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Radiation Detectors and Their Uses written by Mitsuhiro Miyajima and published by . This book was released on 1994 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Search for Neutrinoless Double Beta Decay in 136Xe with EXO 200 written by and published by . This book was released on 2015 with total page 119 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A New Technique to Study the Rydberg States of the Barium Atom by Multiphoton Ionization Laser Spectroscopy written by Alak Chanda and published by . This book was released on 1987 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Measurement of the Xe 136 Two neutrino Double Beta Decay Half life with the NEXT White Detector written by Alberto Usón Andrés and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Search for Double beta Decay of 136Xe to Excited States of 136Ba with the KamLAND Zen Experiment written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: