DOCSLIB.ORG

Calibration and Monitoring for the Borexino Solar Neutrino Experiment

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Calibration and Monitoring for the Borexino Solar Neutrino Experiment Calibration and Monitoring for the Borexino Solar Neutrino Experiment Dissertation submitted to the Faculdade de Ciências da Universidade de Lisboa for the degree of Ph.D. in Physics by José Carvalho Maneira Advisors: Prof. Amélia Maio Prof. Gianpaolo Bellini (University of Milan) Lisbon, November 2001 To my parents and my brother. “The first question I ask myself when something doesn't seem to be beautiful is why do I think it's not beautiful. And very shortly you discover that there is no reason.” John Cage Summary One of the major open issues in Elementary Particle Physics today, the phenomenon of Neutrino Oscillations is a natural consequence of a non-zero neutrino mass and a non-diagonal leptonic mixing matrix. Even if the Standard Model extension to accommodate neutrino oscillations is relatively trivial, a non- zero neutrino mass and mixing is widely considered as a doorway for the Unified Theory of the fundamental interactions. In fact, Super Symmetry naturally explains small neutrino masses through the well-known “see-saw” mechanism. From the experimental point of view, neutrino oscillations are a privileged way of studying the neutrino mass spectrum, since small mass splittings can lead to large and measurable phase differences between interfering quantum-mechanical amplitudes. This is particularly true for Solar Neutrino Experiments, since the large distance between source and detector (1.5´1011 m) allows for a good sensitivity to very small mass differences (down to about 10-11 eV2), not available with the present accelerator and reactor experiments. In fact, the first indication for the possibility of Neutrino Oscillations came from the first measurements of Solar Neutrinos, more than thirty years ago. This hypothesis has been increasingly strengthened by the addition of successive results, from measurements of both Solar and Atmospheric Neutrinos. The experimental constraints on the neutrino mass and mixing parameters have been obtained through the combined analysis of the complementary results from experiments with different potentialities. The Borexino experiment is conceived according to this perspective, since it is aimed at the real-time measurement of the 7Be neutrino flux, a high rate (46 events/day), low energy (0.86 MeV) component of the solar neutrino spectrum for which only indirect, integrated measurements are available up to now. The Physics potential of such a measurement relies on the fact that the 7Be component is monoenergetic so the oscillation patterns are not smoothed by averaging over the energy spectrum and on its low energy, where the presently allowed oscillation solutions predict large rate differences. v The main goal of the Borexino experiment, presently in its final installation phase at the Gran Sasso underground laboratory (LNGS) in Italy, is the detection of 7Be solar neutrinos, requiring both a low energy threshold (250 keV) and a very low level of background from natural radioactivity in the detector materials (10-16 g/g of 238U and 232Th). In order to achieve this, the active detector target will be made of liquid scintillator, pseudocumene with PPO as fluor. However, the use of the scintillation technique limits the data analysis, since it does not allow any directional signature for neutrino events, and their identification is statistical, based on the energy spectrum shape analysis. Therefore, the challenging experimental measurement in Borexino requires precise energy and time calibrations, an accurate control of the background rejection cuts and excellent detector stability. The aim of the work presented in this thesis was to supply the Borexino experiment with the calibration tools necessary to interpret the data and extract the Physics of Neutrino Oscillations. The priority was given to the design, testing, construction and installation of the different calibration systems, but a significant effort was also dedicated to the development of software tools for the energy spectrum analysis and 7Be neutrino identification. The calibration and monitoring systems, face the same challenge that drives some of the most crucial aspects of the Borexino design: to reach and maintain the lowest radioactivity levels ever achieved in any large scale underground detector. This fact limits the mass of any permanent calibration devices in the detector and the risk of radioactive contamination puts significant constraints on the access to the active scintillator volume and on the use of radioactive sources. The strategy followed was to develop non-invasive monitoring systems based on the coupling of optical fibers to lasers and a system to position a radioactive g source (228Th - 200 mCi) in an external region. The calibration and monitoring operations will be scheduled according to the radioactive contamination risk, each step being carried vi out only if the required accuracy was not obtained with the preceding ones. Naturally, the calibration with internal radioactive sources, and in particular, long- lived ones, is the last step in the operational schedule. This thesis is organized in six Chapters. Chapter 1 introduces the Physics of Solar Neutrinos and Neutrino Oscillations, while Chapter 2 describes the goals and design of the Borexino experiment. The design and tests of the Calibration and Monitoring systems are presented in Chapters 3 to 5, while Chapter 6 discusses the sensitivity of Borexino to 7Be Solar Neutrino Physics. The work of the author includes Chapters 3, 4 and 6 and half of Chapter 5. Chapter 3 presents the system for time and charge calibration of the 2200 photomultipliers (PMTs) that detect the light produced in the liquid scintillator. The system is based on the illumination of all the 2200 PMTs with a common light source -- a diode laser -- through a two-stage fiber splitting system, so that each PMT is illuminated by one fiber. We present the requirements, guidelines and design of the system, as well as the results from a prototype of the complete optical chain, built and operated in realistic conditions. From these results and further tests of the final system, now almost fully installed, we expect that all the Borexino PMTs will be illuminated with a low intensity, fast, light pulse, allowing a charge calibration at the single-photoelectron level and a time calibration with a 0.5 ns accuracy. These will be relevant, for an accurate energy measurement and event position reconstruction respectively. Chapter 4 presents the two systems for the optical calibration of the scintillator and buffer liquid. The first of these systems is internal to the active volume and uses absorption and re-emission of ultraviolet laser pulses in the scintillator to measure its optical properties and mimic charged particle scintillation events. We describe the goals and design of the system, as well as the results of preliminary tests with a single photoelectron counting setup. We confirmed that, if the wavelength is low enough (below 300 nm), it will excite primarily the solvent and the fast component of the scintillation decay time is the same as for charged vii particles. This allows us to use laser sources to measure the time distribution of the actual scintillation pulses, necessary for position reconstruction and external background rejection. The second optical calibration system is external to the active volume and it will use a set of light beams in different directions in order to study the stability of the attenuation/scattering length of the buffer liquid and scintillator, that has a strong impact on the efficiency of the internal background rejection cut. The feasibility of this method, in which laser beams are carried to the detector by optical fibers, was tested in the Two Liquid Test Tank (TLTT), a 7 m3 tank built in LNGS for a long-term test of 50 PMTs in realistic conditions, i.e., immersed in the pseudocumene. The time distributions of PMT signals from different zones were used to distinguish between direct, reflected and scattered light and obtain control parameters. Independent measurements of the pseudocumene attenuation length confirmed the sensitivity of these parameters to the transparency changes of the liquid. The design and configuration of the light beam for the final system, now installed, was optimized by means of further tests and Monte Carlo simulations, so we expect to have a good accuracy for the attenuation length monitoring. Chapter 5 presents the systems for calibrations with internal and external radioactive sources. We present the hardware design and the Monte Carlo feasibility studies for a system based on a radioactive g source placed in a region outside the active detector volume, in order to minimize any detector contamination risk. In order to be sensitive to the ± 3.5 % yearly variation of the solar neutrino flux, we need to monitor the counting rate in one of the internal shells of the scintillator volume with an accuracy of 1 %. From our calculations and source insertion design, this can be accomplished with a 200 mCi 228Th source in a short time (a 2 hour run). For completion, we present also the internal source system, designed by our collaborators. Chapter 6 presents a study of the Borexino sensitivity to 7Be solar neutrinos, focusing on the last step of the data processing, that is the energy spectrum viii analysis, since the identification of the 7Be neutrino signal is ultimately done by the recognition of its characteristic “Compton-like” edge. In the energy spectrum study, analytic functions based on the theoretical cross-sections and the detector resolution were used to describe both the neutrino and the background energy distributions. The goal of this strategy is to complement the detailed description of all the expected shapes with a flexible approach that allows the method to better adapt itself to unexpected and not easily reproducible effects. The expected data were generated by Monte Carlo simulations. We studied the sensitivity to 7Be neutrinos for different oscillation scenarios, and its dependence on the internal background rate.
Load more

Recommended publications
  • Radiochemical Solar Neutrino Experiments, "Successful and Otherwise"
    BNL-81686-2008-CP Radiochemical Solar Neutrino Experiments, "Successful and Otherwise" R. L. Hahn Presented at the Proceedings of the Neutrino-2008 Conference Christchurch, New Zealand May 25 - 31, 2008 September 2008 Chemistry Department Brookhaven National Laboratory P.O. Box 5000 Upton, NY 11973-5000 www.bnl.gov Notice: This manuscript has been authored by employees of Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. The publisher by accepting the manuscript for publication acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. This preprint is intended for publication in a journal or proceedings. Since changes may be made before publication, it may not be cited or reproduced without the author’s permission. DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, nor any of their contractors, subcontractors, or their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or any third party’s use or the results of such use of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof or its contractors or subcontractors.
    [Show full text]
  • Searching for Lightweight Dark Matter in Nova Near Detector
    Searching for Lightweight Dark Matter in NOvA Near Detector PoS(FPCP2017)056 Filip Jediný* Czech Technical University in Prague Brehova 7, Prague, Czech Republic E-mail: [email protected] Athanasios Hatzikoutelis University of Tennessee Knoxville Knoxville, TN, USA E-mail: [email protected] Sergey Kotelnikov Fermi National Accelerator Laboratory Kirk and Pine st., Batavia, IL, USA E-mail: [email protected] Biao Wang Southern Methodist University Dallas, TX, USA E-mail: [email protected] The NOvA long-baseline neutrino oscillation experiment is receiving record numbers of 120GeV protons on target from Fermilab's NuMI neutrino beam. We take advantage of our experiment’s sophisticated particle identification algorithms to search for Lightweight Dark Matter (LDM) in the first year of data from the Near Detector of NOvA (300-ton low-Z mass, placed off the beam axis) during the experiment’s first physics runs. Theoretical models of LDM predict that bellow- 10GeV candidates produced in the NuMI target might scatter or decay in the NOvA Near Detector. We simulate an example of the Neutral Vector Portal model with the sensitivity estimate of 10-39 cm2, which corresponds to O(10) LDM candidates per three years of data, looking at single electromagnetic showers between 5 and 15 GeV in a model independent way. The 15th International Conference on Flavor Physics & CP Violation 5-9 June, 2017 Prague, Czech Republic * Speaker Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0). http://pos.sissa.it/ Searching for LDM in NOvA ND Filip Jediný 1.
    [Show full text]
  • Neutrino Book
    The challenge of neutrinos Preparing the Gargamelle bubble chamber at CERN in 1969. In 1973 the chamber took the first historic photographs of neutral current interactions. (Photo CERN 409.9.69) Neutrino book Gargamelle and Neutral Currents - The Story of a Vital Discovery by Andre Rousset Andre Rousset's book (in French - Gargamelle et les Courants Neutres - Ecole des Mines de Paris) tells the story of Gargamelle and the discov­ ery at CERN in 1973 of neutral currents, the cornerstone of the electroweak theory. This vital discov­ ery helped to give credence to the Standard Model of particle physics. Rousset is both an observer and one of the key figures in the story. His book is lively and well docu­ mented; in it he uses archive material to ensure the accuracy of his infor­ mation on dates, choices and deci­ sions. ously" to the project was probably in an interesting manner the theo­ After an introduction to particle what swung the decision. rists' "green light", giving the go- physics which puts into perspective Construction took five years, during ahead to the experimentalists. In fact, the electroweak theory unifying weak which many problems were encoun­ the European collaboration (Aachen, and electromagnetic interactions, tered, right up to the fault in the main Brussels, CERN, Ecole Polytechni­ Rousset comes straight to the point. part of the chamber which caused que, Milan, Orsay, UC London) was From the late 1950s onwards he was delays and, a few years later, was to divided between a study of the quark- involved in the construction of the prove fatal to the detector.
    [Show full text]
  • Gigantic Japanese Detector Seeks Supernova Neutrinos Tracing the History of Exploding Stars Is a Goal of the Revamped Super-Kamiokande
    NEWS IN FOCUS ASAHI SHIMBUN/GETTY Observations by the Super-Kamiokande neutrino detector have forced theorists to amend the standard model of particle physics. PHYSICS Gigantic Japanese detector seeks supernova neutrinos Tracing the history of exploding stars is a goal of the revamped Super-Kamiokande. BY DAVIDE CASTELVECCHI weight. These data will help astronomers to detector much better at distinguishing between better understand the history of supernovae different types, or ‘flavours’, of neutrino, as well leven thousand giant orange eyes in the Universe — but the neutrinos that the as their antiparticles, antineutrinos. confront the lucky few who have explosions emit have been difficult to detect. In 1987, the Kamiokande detector, Super-K’s entered the Super-Kamiokande under- “Every 2–3 seconds, a supernova goes off smaller predecessor, detected the first neutri- Eground neutrino observatory in Japan — by somewhere in the Universe, and it produces nos from a supernova. The dozen neutrinos far the largest neutrino detector of its kind in 1058 neutrinos,” says Masayuki Nakahata, came from Supernova 1987A, which occurred the world. A chance to see these light sensors who heads the Super-K, an international col- in the Large Magellanic Cloud, a small galaxy is rare because they are usually submerged in laboration led by Japan and the United States. that orbits the Milky Way. Head experimenter 50,000 tonnes of purified water. But a major With the upgrade, the detector should be able Masatoshi Koshiba shared the 2002 Nobel revamp of Super-K that was completed in to count a few of these ‘relic’ neutrinos every physics prize partly for that discovery.
    [Show full text]
  • The Gallex Project Deqq Q05573
    BNL-43669 C-3557 BNL—43669 THE GALLEX PROJECT DEQQ Q05573 T.KIRSTEN Max-Planck-Institut für Kernphysik P.OMox 103980 6900 Heidelberg GALLEX GALLEX COLLABORATION: M.Breitenbach, W.Hampel, G.Heusser, J.Kiko, T.Kirsten, H.Lalla, A.Lenzing, E.Pernicka, R.Plaga, B.Povh, C.Schlosser, H.Völk, R,Wink, K.Zuber Max-Planck-Institut für Kernphysik.Heidelberg R.v.Ammon, K.Ebert, E.Henrich, L.Stieglitz Kernforschungszentrum Karlsruhe- KFK ¿Bellota JAN 2 2 Dip.dì Fisica delVUnìversità,Mìlano and Laboratori Nazionali del Gran Sasso-INFN O.Creraonesi, EJFiorini, C.Liguori, S.Ragazzi, L.Zanoiti Dip.di Fisica dell'Università, Milano R.Mössbauer,A.Urban Physik Dept. EIS , Technische Universität München G.Berthomieu, E.Schatzman Université de Nice-Observatoire S.d'Angelo, C.Bacci, P.Belli, R.Bernabei, L.Paoluzi, R.Santonico H-Universita di Roma -INFN M.Cribier, CDupont, B.Pichard, J.Rich, M.Spiro, T.Stolarczyk, C.Tao, D.Vignaud Centre d'Etudes Nucléaires de Saclay, Gif-sur Yvette I.Dostrovsky Weizmann Institute of Sciences,Rehovot G.Friedlander,R.L.Hahn,J.K.Rowley,R.W.Stoenner,J.Weneser Brookhaven National Laboratory, Upton,N.Y. ABSTRACT. The GALLEX collaboration aims at the detection of solar neutrinos in a radiochemical experiment employing 30 tons of Gallium in form of concentrated aqueous Gallium-chloride solution/The detector is primarily sensitive to the otherwise inaccessible pp-neutrinos. Details of the experiment have been repeatedly described before [1-7]. .Here we report the present status of implementation in the Laboratori Nazionali del Gran Sasso (Italy). So far, 12.2 tons of Gallium are at hand.The present status of development allows to start the first full scale run at the time when 30 tons of Gallium become available.This date is expected to be January, 1990.
    [Show full text]
  • Plastic Anti-Neutrino Detector Array (PANDA)
    Plastic Anti-Neutrino Detector Array (PANDA) Yo Kato (The University of Tokyo) Yasuhiro KurodaA, Shugo OguriB, Nozomu TomitaA, Ryoko NakataA, Chikara ItoC, Masato TakitaD, Yoshizumi InoueE, Makoto MinowaA,F The University of TokyoA High Energy Accelerator Research Organization (KEK)B Japan Atomic Energy Agency (JAEA)C ICRR, The University of TokyoD ICEPP, The University of TokyoE RESCEU, The University of TokyoF Applied Antineutrino Physics (AAP) Arlington, 7 Dec 2015 Reactor monitoring Inspection by IAEA - Nonproliferation of nuclear technology - Current inspection tools are “intrusive”, such as -- neutron monitoring beside reactor cores -- fuel monitoring before and after reactor operation International Atomic Energy Agency -> Burden for both operator and inspector IAEA proposed a “non-intrusive” inspection tool. Final Report: Focused Workshop on Antineutrino Detection Safeguards Applications (2008) Reactor monitoring using an antineutrino detector - High penetration -> can be detected outside a reactor building - No alternative source -> cannot hide reactor operation -> Suitable for inspection ! 7 Dec 2015 AAP2015 2 Reactor antineutrino Nuclear fission of 235U -> neutron-rich nuclei - 6 antineutrinos - 200MeV per fission decay of neutron-rich nuclei -> antineutrino - - 3GWth reactor emits 6×1020 neutrinos/s Prompt event - Energy deposit of e+ - e+ + e− → 2훾 Delayed coincidence Delayed event gadolinium - Gamma rays by Gd neutron plastic scintillator capture (Total 8 MeV) 7 Dec 2015 AAP2015 3 PANDA（Plastic Anti-Neutrino Detector Array）
    [Show full text]
  • Neutrino Interaction Measurements Using the T2K Near Detectors
    Neutrino interaction measurements using the T2K near detectors Daniel G Brook-Roberge for the T2K Collaboration University of British Columbia, Vancouver, BC, Canada E-mail: [email protected] Abstract. The T2K near detectors provide a rich facility for measuring neutrino interactions in a high-flux environment. This talk will discuss the near detector CC-inclusive normalization analysis for the T2K oscillation result in detail, along with the present result, and describe the plan for its extension to more sophisticated measurements. Selection criteria for CCQE interactions will be presented, as will a strategy for calculating cross-section difference between plastic scintillator and water. The unique capacities of the near detectors to measure other exclusive CC and NC channels in a narrow-band off-axis beam will also be explored. 1. Introduction The T2K (Tokai to Kamioka) long-baseline neutrino oscillation experiment[1] aims to make high- precision measurements of oscillation parameters using a beam of muon neutrinos. In particular, the appearance of electron neutrinos in the beam is studied in an effort to measure a non-zero value of the mixing parameter θ13. Electron neutrino appearance provides a particular challenge for the near detector, as the electron neutrino fraction in the muon neutrino beam is the most significant background to this measurement. The T2K experiment has had two experimental runs; one at beam power up to 50 kW from January to June 2010, and one at beam power up to 150 kW from November 2010 to March 2011, when it was cut short by the Tohoku earthquake. 1.43 × 1020 protons on target were accumulated by T2K prior to the earthquake.
    [Show full text]
  • High Energy Neutrino Detection with the ANTARES Underwater Čerenkov Telescope
    Scuola di Dottorato “Vito Volterra” Dottorato di Ricerca in Fisica – XXII ciclo High energy neutrino detection with the ANTARES underwater Čerenkov telescope Thesis submitted to obtain the degree of Doctor of Philosophy (“Dottore di Ricerca”) in Physics October 2009 by Manuela Vecchi Program Coordinator Thesis Advisors Prof. Vincenzo Marinari Prof. Antonio Capone Dr. Fabrizio Lucarelli to my parents Contents Introduction ix 1 Neutrino astronomy in the context of multimessenger approach 1 1.1 AstrophysicalNeutrinos . 1 1.2 Themulti-messengerconnection . 4 1.3 Galactic Sources of High Energy Neutrinos . 6 1.3.1 SuperNovaRemnants ...................... 8 1.3.2 Microquasars ........................... 9 1.4 Extra-Galactic Sources of High Energy Neutrinos . 10 1.4.1 GammaRayBursts ....................... 10 1.4.2 ActiveGalacticNuclei . 12 2 High energy neutrino detection 17 2.1 Recent developments in neutrino physics . 17 2.2 High energy neutrino detection methods . 20 2.3 Highenergyneutrinotelescopes. 24 2.3.1 Čerenkov high energy neutrino detectors . 24 2.3.2 Radiodetectiontechnique . 27 2.3.3 Acoustic detection technique . 29 2.3.4 The Pierre Auger Observatory as a neutrino telescope . 31 3 The ANTARES high energy neutrino telescope 33 3.1 Detector layout and site dependent properties . ..... 33 3.1.1 Light transmission properties at the ANTARES site . 37 3.2 Environmentalbackground . 38 3.3 The biofouling effect at the ANTARES site . 39 3.3.1 Experimentaltechnique . 40 3.3.2 Dataanalysis ........................... 41 3.4 Calibration ................................ 46 3.4.1 TimeCalibration......................... 46 3.4.2 Alignment............................. 47 3.4.3 ChargeCalibration. 47 3.5 Physicalbackground ........................... 49 3.6 Data acquisition system, trigger and event selection .
    [Show full text]
  • 21.8 N&V PJ BG.Indd
    NEWS & VIEWS NATURE|Vol 454|21 August 2008 OBITUARY Yoji Totsuka (1942–2008) Leader in the discovery of neutrino oscillations. Yoji Totsuka, a major figure in the world of of the supernova and of the neutrinos particle physics, died on 10 July after a long themselves. battle with cancer. He was a leading light Shortly after the supernova, Koshiba in the thrilling advances in the physics of retired and Totsuka became leader of neutrinos over the past 30 years, and was the Kamiokande project. Two seminal a notably resolute figure in seeing through results from the group were subsequently the rebuilding of the Super-Kamiokande published. The first observed a deficit in neutrino detector after a disastrous accident atmospheric neutrinos that could not be in 2001. explained by systematic experimental errors Born on 6 March 1942, in Fuji, Japan, or uncertainties in the background neutrino Totsuka received his bachelor’s, master’s and flux. Instead, some “as-yet-unaccounted-for PhD degrees from the University of Tokyo. physics”, as the paper put it, might explain His thesis project studied ultra-high-energy the data. The second crucially confirmed the particle interactions, so kick-starting his solar neutrino deficit recorded by Davis. lifelong passion for particle physics. As a In 1991, Totsuka obtained funding for a Totsuka also supervised the successful research associate with the University of successor to Kamiokande. This was Super- Belle B-factory, where particles known as Tokyo, he then travelled to the Deutsches Kamiokande, an underground detector B-mesons were generated to study differences Electron Synchrotron Laboratory in that contained 50,000 tons of water.
    [Show full text]
  • Arxiv:1606.02896V3 [Physics.Ins-Det] 11 Oct 2016 1Corresponding Author; E-Mail: [email protected]
    DANSS: Detector of the reactor AntiNeutrino based on Solid Scintillator I. Alekseev a;b;c, V. Belov d, V. Brudanin d, M. Danilov b;c;e, V. Egorov d;f 1, D. Filosofov d, M. Fomina d, Z. Hons d;g, S. Kazartsev d;f , A. Kobyakin a;c, A. Kuznetsov d, I. Machikhiliyan a, D. Medvedev d, V. Nesterov a, A. Olshevsky d, D. Ponomarev d, I. Rozova d, N. Rumyantseva d, V. Rusinov a, A. Salamatin d, Ye. Shevchik d, M. Shirchenko d, Yu. Shitov d;h, N. Skrobova a;c, A. Starostin a, D. Svirida a, E. Tarkovsky a, I. Tikhomirov a, J. Vl´aˇsek d;i, I. Zhitnikov d, D. Zinatulina d a ITEP { State Scientific Center, Institute for Theoretical and Experimental Physics, Moscow, Russia b MEPhI { National Research Nuclear University MEPhI, Moscow, Russia c MIPT { Moscow Institute of Physics and Technology, Moscow Region, Dolgoprudny, Russia d JINR { Joint Institute for Nuclear Research, Moscow Region, Dubna, Russia e LPI RAS { Lebedev Physical Institute of the Russian Academy of Sciences, Moscow, Russia f DSU { Dubna State University, Moscow Region, Dubna, Russia g NPI { Nuclear Physics Institute, Reˇz,ˇ Czechia h ICL { Imperial College London, SW7 2AZ, London, United Kingdom i CTU { Czech Technical University in Prague, Czechia Keywords: Neutrino detectors Abstract The DANSS project is aimed at creating a relatively compact neutrino spectrometer which does not contain any flammable or other dangerous liquids and may therefore be located very close to the core of an industrial power reactor. As a result, it is expected that high neutrino flux would provide about 15,000 IBD interactions per day in the detector with a sensitive volume of 1 m3.
    [Show full text]
  • Results and Perspectives in Solar Neutrino Detection with Borexino
    Results and perspectives in solar neutrino detection with Borexino Lino Miramonti on behalf of the Borexino Collaboration Dipartimento di Fisica, Università degli Studi di Milano & INFN-Sezione di Milano 1 Solar neutrinos fluxes Electron neutrinos (νe) are copiously produced by thermonuclear processes that power the Stars In the Sun about 99 % of of the energy is produced in the pp chain ne from: pp pep 7Be 8B hep 2 Solar neutrinos fluxes Beside the pp chain there is also the CNO cycle which represents ∼1-2 % of the Sun energy CNO cycle is important for massive stars ne from: 13N 15O CNO 17F So far CNO νe have never been detected! 3 Solar neutrinos fluxes Expected n fluxes from the Standard Solar Model (SSM) In the middle of ’60s a solar neutrino detector was built in order to test the validity of the Standard Solar Model (SSM). 4 Solar neutrinos detection – SSM and Neutrino Oscillations There are two ways to detect solar neutrinos: % radiochemical experiments n +AAXYe®+- "#$� radioactive (Inverse Beta Decay) eZ Z+1 daughter isotope. ( e) --σ νµ,τ 1 real time experiments ≈ nn+ee®+ ( e) 6 (Elastic Scattering) xxσ νe More than 40 years of solar neutrino experiments have successfully detected solar neutrinos and validate the SSM. We know that solar neutrinos oscillates in vacuum at low energy and for high energy (multi-MeV) the conversion is enhanced by the high electron density in the core of the Sun (MSW effect Mikheyev-Smirnov-Wolfenstein). Global 3ν oscillation analysis 1 P3ν = cos4 θ 1+ cos2θ M cos2θ NuFIT 3.2 (2018) ee 2 13 ( 12 12 ) cos2θ − β cos2θ M = 12 12 2 cos2θ − β +sin2 2θ regions at 1σ, 90%, ( 12 ) 12 2σ, 99%, 3σ CL 2 2G cos2 θ n E where F 13 e ν β = 2 Δm12 5 Solar Spectroscopy with Borexino from 200 keV Radiochemical experiments (Homestake, ν flux as predicted by SSM Gallex, SAGE) integrate in time and energy.
    [Show full text]
  • Neutrino Observatory Management & Operations Plan
    IceCube Neutrino Observatory Management & Operations Plan Neutrino Observatory Management & Operations Plan December 2019 Revision 4.0 December 2019 1 IceCube Neutrino Observatory Management & Operations Plan IceCube MANAGEMENT & OPERATIONS PLAN SUBMITTED BY: Francis Halzen Kael Hanson IceCube Principal Investigator Co-PI and IceCube Director of Operations University of Wisconsin–Madison University of Wisconsin–Madison Albrecht Karle Co-PI and Associate Director for Science and Instrumentation University of Wisconsin–Madison James Madsen Associate Director for Education and Outreach University of Wisconsin–River Falls Catherine Vakhnina Resource Coordinator Paolo Desiati Coordination Committee Chair John Kelley Detector Operations Manager Benedikt Riedel Computing and Data Management Services Manager Juan Carlos Diaz-Velez Data Processing and Simulation Services Manager Alex Olivas Software Coordinator Summer Blot, Keiichi Mase Calibration Coordinator December 2019 2 IceCube Neutrino Observatory Management & Operations Plan Revision History Date Section Revision Action Revised Revised 1.0 06/9/2016 First version 2.0 05/31/2017 Updated for M&O PY2 3.0 12/12/2018 Updated for M&O PY3 4.0 03/20/2020 Updated PY4 plan w new Org Chart December 2019 1 IceCube Neutrino Observatory Management & Operations Plan Table of Contents List of Acronyms and Terms ........................................................................................................................ 5 1 Preface .................................................................................................................................................
    [Show full text]