DOCSLIB.ORG

Enriched Xenon Observatory for Double Beta Decay

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Enriched Xenon Observatory for Double Beta Decay Why are neutrinos so light? Early results from the EXO experiment Carter Hall University of Maryland Spin 1/2 mass spectrum 1st 2nd 3rd TeV t b τ GeV c s µ ~105 d MeV u e Fermion Mass Fermion keV beta decay, cosmology ~105 eV at least one neutrino meV quantum interference effects Neutrino mass from beta decay (1932) “The greatest similarity to the empirical curve is given by the theoretical curve for m = 0. Hence we conclude that the rest mass of the neutrino is either zero, or, in any case, very small in comparison to the mass of the electron.” A quantum mechanical 3-state system Δm2 νµ ντ νe MINOS experiment – Fermilab - Minnesota L = 734 km L/E of 1st oscillation minimum measures Δm2 ~ (50 meV)2 One neutrino mass eigenstate must have at least m ~ 50 meV. A quantum mechanical 3-state system Δm ~ 50 meV KamLAND experiment – Japan Δm2 ~ (9 meV)2 Neutrino mass hierarchy 50 meV 9 meV Spin 1/2 mass spectrum 1st 2nd 3rd TeV t b τ GeV c s µ d Higgs? MeV u e Fermion Mass Fermion keV eV at least one neutrino meV Higgs Mechanism Spin ½ Fermions e- e+ e+ e- spin-up spin-down spin-up spin-down electron positron positron electron Dirac: Four degrees of freedom to describe a spin ½ particle Spin ½ Fermions No weak interactions e- e+ e+ e- right handed left-handed right handed left-handed electron positron positron electron Dirac: Four degrees of freedom to describe a spin ½ particle Spin ½ Fermion - Handedness Complex phase 360° physical rotation 360° physical rotation Fermion mass terms connect left-handed and right-handed states top quark: H H H H tL tL tL tL tL t t tR R R tR tR H H H H H mass term H electron - - e L - e R e R H Dirac mass term: conserves charge (e- →e-) What about a massless neutrino? No weak interactions...... no interactions at all – completely sterile! L=+1 L=-1 L=-1 L=+1 right handed left-handed right handed left-handed neutrino anti-neutrino anti-neutrino neutrino The old standard model “explanation” for massless neutrinos: Nature “had no use” for sterile states, so they are left out. This prevents the Higgs from giving neutrinos a Dirac mass. But neutrinos do have mass. Homestake Super-K Solar Neutrino Experiment Sudbury Neutrino Observatory No problem..... just put the sterile states back. Sterile L=+1 L=-1 L=-1 L=+1 right handed left-handed right handed left-handed neutrino anti-neutrino anti-neutrino neutrino Dirac neutrino: carries a conserved charge (lepton number) Types of Neutrino mass terms Dirac Neutrino Mass Conserves lepton number Standard model ν X ν Higgs can create R L only a Dirac mass Majorana Mass 1 νR X νL violates conservation of Majorana Mass 2 lepton number Neutrinos may X ν have all three νR L types of mass terms See-saw mechanism generated by the Higgs Suppose mDirac ~ 100 GeV, like the top quark 15 and mMajorana ~ 10 GeV generated by some type of new physics at the Grand Unification energy scale Then we would observe two Majorana neutrinos, with like atmospheric ν oscillations too large to be seen directly M.Gellman, R.Slanksy, P.Ramond, R.Mohapatra, G.Senjanovic Spin 1/2 mass spectrum 1st 2nd 3rd TeV t b τ GeV c s µ d Higgs? MeV u e Suppressed by Fermion Mass Fermion keV Grand Unification physics? eV at least one neutrino meV Dirac and Majorana neutrinos Dirac fermion: particle is charged, so (e-, µ-, τ-, quarks). A Dirac neutrino carries lepton number: Majorana fermion: particle carries no charge, so A Majorana neutrino cannot carry lepton number. Does the neutrino carry lepton number? Is the neutrino its own antiparticle? Use nuclear physics to test neutrino charge properties: beta decay e - acts a neutrino source L Majorana neutrino W-W- n ν p Inside a nucleus Use nuclear physics to test neutrino charge properties: eL- Majorana neutrino? W-W- 2n ν eL- W- Inside a nucleus 2p second vertex acts as the detector Neutrinoless Double Beta Decay (ββ0ν) Forbidden if neutrino mass is Dirac only eL- N(Z,A)→N(Z+2,A)e-e- Majorana neutrino W-W- 2n ν eL- m(ν) X W- Forbidden Inside a nucleus by lepton number conservation if neutrinos are Dirac. “Neutrino mass mechanism” 2p for double beta decay second vertex acts as the detector Many types of new physics lead to ββ0ν Right handed weak currents, leptoquarks, supersymmetry, ect., d u W- e- h-- W- e- d u “Doubly charged Higgs mechanism” for double beta decay Does this spoil neutrino physics interpretations of ββ0ν ? Black Box Theorem Anything that converts ν ν into ν ν means that neutrinos are Majorana If we see ββ0ν, we know that Majorana neutrinos exist! The ββ0ν half-life depends DIRECTLY on the absolute neutrino masses Decay rate (due to the heavy chiral suppression): Majorana effective mass phases phase space mixing matrix Nuclear Matrix (with phases) Element mass eigenvalues We can use the ββ0ν decay rate to measure the absolute neutrino mass if: 1) neutrinos are Majorana 2) we have a reliable calculation of the nuclear matrix element 3) the neutrino mass mechanism dominates the decay What ββ0ν can tell us about the neutrino mass scale pseudo- degenerate inverted hierarchy normal hierarchy Figure from Strumia & Vissani, Nucl. Phys. B 726 294 (2005) Two-Neutrino Double Beta Decay: eL- W-W- 2n eL- νR Two neutrons convert to two protons and four leptons. W- νR First direct observation by Moe, Elliott, and Hahn 2p in 100Mo (1988) No direct implications for neutrino mass, but useful for constraining and testing the nuclear matrix element calculations ββ0ν signature: a peak in the ββ energy spectrum ββ2ν spectrum (normalized to 1) 0νββ peak (5% FWHM) (normalized to 10-6) ββ0ν signal (5% FWHM) (normalized to 10-2) Summed electron energy in units of the kinematic endpoint (Q) What nuclei are ββ candidates? atomic mass atomic decay energy number of protons Choose a ββ source isotope: Q value natural Decay candidate (MeV) abundance (%) The most sensitive double beta decay experiments to date are based on 76-Germanium. Heidelberg-Moscow (76Ge) energy spectrum Q value Half-life limit: 1.9 x 1025 years (H-M and IGEX) Majorana neutrinos ruled out for masses greater than ~0.35-1.0 eV Germanium diode experiments – Heidelberg-Moscow - 2001 Moore’s Law for ββ0ν black box EXO-200 goal See-saw theorem ββ2ν Δm2 KamLAND-Zen GERDA Majorana CUORE-0 SNO+ Backgrounds: all ordinary radioactive decay Alpha decay beta decay gamma decay Shielding gammas is difficult! Gamma interaction cross section typical ββ Q values gammas travel about 2 cm before scattering in lead Lead shielding Nuclide half lives “Stable”: ~1015 years ββ0ν halflife is 1010 times longer “Peninsula (at least) of stability” half-life comparable to age of the earth half-life short compared to age of the earth Peninsula of Stability Uranium-235 Curium-247 Plutonium-244 Thorium-232 Uranium-238 Uranium-238 decay chain start Thorium-232 decay chain start gamma sources end end Ordinary radioactive decay here on earth K-40 Tl-208 Bi-214 (Th-232) (U-238) ββ0ν Q values: Ge-76 Xe-136 Te-130 Get smarter: Single Ba+ ion detection 136Xe→136Ba++ e-e- Daughter identified by optical spectroscopy of Ba+, well studied in ion traps for more than[Neuhauser, 25 years Hohenstatt, Toshek, Dehmelt, Phys. Rev. A 22 (1980) 1137] - very specific signature (“Λ” shelving) - cycling 493/650 nm transitions gives a fluorescence rate of ~108 Hz (in vacuum) plenty of light! Ba+ Tagging: Ion Trap + fluorescence ~9σ discrimination in 5s integration M.Green et al., Phys Rev A76 (2007) 023404 B.Flatt et al., NIM A578 (2007) 409 Prototype electrostatic probe to study ion grabbing and release Probe tip Liquid xenon cell Th+ source Prototype probe collects Th+ in liquid xenon, then we observe them with an α counter above the liquid surface. Grabbing ions from liquid xenon refrigerator cold head xenon condenser 3” diameter access port 3-liter (10 kg) liquid xenon storage vessel ITEP ИТЭФ The EXO-200 experiment 200 kg of xenon enriched to 80% in 136Xe: Liquid xenon calorimetry Measure the event energy by collecting the ionization on the anode and/or observing the scintillation. EXO-200: the first 200 kg ββ0ν experiment Copper liquid HFE-7000 copper cryostat xenon vessel cryofluid 25 cm lead shielding EXO-200 cryostat & lead 2150 feet underground at the WIPP facility in Carlsbad, NM Before EXO With EXO EXO-200 liquid xenon vessel: a thin copper balloon • Very light (wall thickness 1.5 mm, total weight 15 kg), to minimize material. • All parts machined under 7 ft of concrete shielding to reduce activation by cosmic rays. • Different parts are e-beam welded together at Applied Fusion. • End caps are TIG welded. A liquid xenon vessel made of teflon(!) EXO xenon handling &purification system purifier valve & instrumentation manifold xenon condenser xenon condenser condenser dual xenon compressors LXe boil-off heater Commissioning of cryogenics and fluid handling – 2007-2009 Dummy LXe vessel (stainless steel) EXO-200 TPC Construction EXO-200 TPC Construction EXO-200 TPC Construction A fully instrumented half-detector Final TPC installation - January 2010 Sensitivity : 0.1 ppb O2 Screen the xenon for impurities 1.0 ppb N2 0.06 ppb CH4 with mass spectrometry 0.5 ppt Kr Xe is constant due to cold trap ~few ppm Ar 18 ppb N2 5 ppb O2 0.25 ppb CH4 open leak valve, flow through bypass bypass gas purifier gas purifier gas purifier A cosmic ray muon in the EXO liquid xenon TPC Four views of the same muon track: 2 TPCs x X&Y views Single-Site Event Double site event – gamma scatter Calibration Source Run Sources: 137Cs, 60Co, 228Th y z x Various calibration sources can be brought to several positions just outside the detector x-y distribution of events clearly shows excess near the source location 70 Radioactive Source Calibration Run single - cluster multiple - cluster granularity from 9 mm wire spacing γ γ 720 720 • Calibration runs compared to simulation -There are no free parameters for these comparisons (worst agreement is +8%) Physics Data – June/July 2011 single - cluster multiple - cluster zoomed in 720 720 720 • 31 live-days of data • 63 kg active mass • Signal / Background ratio 10:1 -as good as 40:1 for some extreme fiducial volume cuts Physics Data – June/July 2011 Rate vs.
Load more

Recommended publications
  • Presentation File
    The Future of High Energy Physics and China’s Role Yifang Wang Institute of High Energy Physics, Beijing HKUST, Sep. 24, 2018 A Very Active Field ILC,FCC, China-based LHC: ATLAS/CMS CEPC/SPPC High China-participated Others Energy Compositeness AMS, PAMELA Extra-dimensions Supersymmetry Antimatter Higgs CP violation Daya Bay, JUNO,T2K,Nova, SuperK,HyperK,LBNF/DUNE, Icecube/PINGU, KM3net/ORKA, Neutrinos SNO+,EXO/nEXO, KamLAND-Zen, Precision Standard COMET, tests Model Gerda,Katrin… mu2e, g-2, K-decays,… Hadron physics Cosmology & QCD Standard Model of Cosmology Rare decays Dark matter LUX, Xenon, LZ, BESIII,LHCb, Axions PandaX, CDEX, High BELLEII, Darkside, … precision PANDA,… ADMX,… Fermi, DAMPE, AMS,… 2 Roadmaps of HEP in the World • Japan (2012) – If new particles(e.g. Higgs) are discovered, build ILC – If θ13 is big enough, build HyperK and T2HK • EU (2013) – Continue LHC, upgrade its luminosity, until 2035 – Study future circular collider (FCC-hh or FCC-ee) • US (2014) – Build long baseline neutrino facility LBNF/DUNE – Study future colliders A new round of roadmap study is starting 3 Where Are We Going ? • ILC is a machine we planned for ~30 years, way before the Higgs boson was discovered. Is it still the only machine for our future ? • Shall we wait for results from LHC/HL-LHC to decide our next step ? • What if ILC could not be approved ? • What is the future of High Energy Physics ? • A new route: – Thanks to the low mass Higgs, there is a possibility to build a circular e+e- collider(Higgs factory) followed by a proton machine in the same tunnel – This idea was reported for the first time at the “Higgs Factory workshop(HF2012)” in Oct.
    [Show full text]
  • The Gran Sasso Underground Laboratory Program
    The Gran Sasso Underground Laboratory Program Eugenio Coccia INFN Gran Sasso and University of Rome “Tor Vergata” [email protected] XXXIII International Meeting on Fundamental Physics Benasque - March 7, 2005 Underground Laboratories Boulby UK Modane France Canfranc Spain INFN Gran Sasso National Laboratory LNGSLNGS ROME QuickTime™ and a Photo - JPEG decompressor are needed to see this picture. L’AQUILA Tunnel of 10.4 km TERAMO In 1979 A. Zichichi proposed to the Parliament the project of a large underground laboratory close to the Gran Sasso highway tunnel, then under construction In 1982 the Parliament approved the construction, finished in 1987 In 1989 the first experiment, MACRO, started taking data LABORATORI NAZIONALI DEL GRAN SASSO - INFN Largest underground laboratory for astroparticle physics 1400 m rock coverage cosmic µ reduction= 10–6 (1 /m2 h) underground area: 18 000 m2 external facilities Research lines easy access • Neutrino physics 756 scientists from 25 countries Permanent staff = 66 positions (mass, oscillations, stellar physics) • Dark matter • Nuclear reactions of astrophysics interest • Gravitational waves • Geophysics • Biology LNGS Users Foreigners: 356 from 24 countries Italians: 364 Permanent Staff: 64 people Administration Public relationships support Secretariats (visa, work permissions) Outreach Environmental issues Prevention, safety, security External facilities General, safety, electrical plants Civil works Chemistry Cryogenics Mechanical shop Electronics Computing and networks Offices Assembly halls Lab
    [Show full text]
  • Effective Neutrino Masses in KATRIN and Future Tritium Beta-Decay Experiments
    PHYSICAL REVIEW D 101, 016003 (2020) Effective neutrino masses in KATRIN and future tritium beta-decay experiments † ‡ Guo-yuan Huang,1,2,* Werner Rodejohann ,3, and Shun Zhou1,2, 1Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China 2School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China 3Max-Planck-Institut für Kernphysik, Postfach 103980, D-69029 Heidelberg, Germany (Received 25 October 2019; published 3 January 2020) Past and current direct neutrino mass experiments set limits on the so-called effective neutrino mass, which is an incoherent sum of neutrino masses and lepton mixing matrix elements. The electron energy spectrum which neglects the relativistic and nuclear recoil effects is often assumed. Alternative definitions of effective masses exist, and an exact relativistic spectrum is calculable. We quantitatively compare the validity of those different approximations as function of energy resolution and exposure in view of tritium beta decays in the KATRIN, Project 8, and PTOLEMY experiments. Furthermore, adopting the Bayesian approach, we present the posterior distributions of the effective neutrino mass by including current experimental information from neutrino oscillations, beta decay, neutrinoless double-beta decay, and cosmological observations. Both linear and logarithmic priors for the smallest neutrino mass are assumed. DOI: 10.1103/PhysRevD.101.016003 I. INTRODUCTION region close to its end point will be distorted in com- parisontothatinthelimitofzeroneutrinomasses.This Neutrino oscillation experiments have measured with kinematic effect is usually described by the effective very good precision the three leptonic flavor mixing neutrino mass [7] angles fθ12; θ13; θ23g and two independent neutrino 2 2 2 2 mass-squared differences Δm21 ≡ m2 − m1 and jΔm31j≡ qffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi 2 − 2 2 2 2 2 2 2 jm3 m1j.
    [Show full text]
  • Neutrino Mass Analysis with KATRIN
    Technical University Munich Max Planck Institute for Physics Physics Department Werner Heisenberg Institute Advanced Lab Course Neutrino Mass Analysis with KATRIN Christian Karl, Susanne Mertens, Martin Slezák Last edited: September 2, 2020 Contents 1 Introduction 3 2 The KATRIN Experiment5 2.1 Neutrino Mass Determination from Beta-Decay............................5 2.2 Molecular Tritium as Beta-Decay Source................................6 2.3 Measuring Principle: MAC-E Filter Electron Spectroscopy.....................7 2.4 Experimental Setup.............................................8 2.4.1 Rear Section.............................................8 2.4.2 Windowless Gaseous Tritium Source..............................8 2.4.3 Pumping Sections.........................................9 2.4.4 Pre- and Main-Spectrometer...................................9 2.4.5 Focal Plane Detector........................................ 10 2.5 Modelling of the Integrated Beta-Decay Spectrum.......................... 10 2.5.1 Final State Distribution...................................... 10 2.5.2 Doppler Effect........................................... 11 2.5.3 Response Function......................................... 12 2.5.4 Model of the Rate Expectation................................. 13 3 Basic Principles of Data Analysis 15 3.1 Maximum Likelihood Analysis...................................... 15 3.2 Interval Estimation............................................. 16 4 Tasks 18 4.1 Understanding the Model........................................
    [Show full text]
  • Required Sensitivity to Search the Neutrinoless Double Beta Decay in 124Sn
    Required sensitivity to search the neutrinoless double beta decay in 124Sn Manoj Kumar Singh,1;2∗ Lakhwinder Singh,1;2 Vivek Sharma,1;2 Manoj Kumar Singh,1 Abhishek Kumar,1 Akash Pandey,1 Venktesh Singh,1∗ Henry Tsz-King Wong2 1 Department of Physics, Institute of Science, Banaras Hindu University, Varanasi 221005, India. 2 Institute of Physics, Academia Sinica, Taipei 11529, Taiwan. E-mail: ∗ [email protected] E-mail: ∗ [email protected] Abstract. The INdias TIN (TIN.TIN) detector is under development in the search for neutrinoless double-β decay (0νββ) using 90% enriched 124Sn isotope as the target mass. This detector will be housed in the upcoming underground facility of the India based Neutrino Observatory. We present the most important experimental parameters that would be used in the study of required sensitivity for the TIN.TIN experiment to probe the neutrino mass hierarchy. The sensitivity of the TIN.TIN detector in the presence of sole two neutrino double-β decay (2νββ) decay background is studied at various energy resolutions. The most optimistic and pessimistic scenario to probe the neutrino mass hierarchy at 3σ sensitivity level and 90% C.L. is also discussed. Keywords: Double Beta Decay, Nuclear Matrix Element, Neutrino Mass Hierarchy. arXiv:1802.04484v2 [hep-ph] 25 Oct 2018 PACS numbers: 12.60.Fr, 11.15.Ex, 23.40-s, 14.60.Pq Required sensitivity to search the neutrinoless double beta decay in 124Sn 2 1. Introduction Neutrinoless double-β decay (0νββ) is an interesting venue to look for the most important question whether neutrinos have Majorana or Dirac nature.
    [Show full text]
  • Search for Neutrinos from TANAMI Observed AGN Using Fermi
    Search for neutrinos from TANAMI observed AGN using Fermi lightcurves with ANTARES Suche nach Neutrinos von TANAMI-AGN unter Verwendung von Fermi-Lichtkurven mit ANTARES Der Naturwissenschaftlichen Fakultät der Friedrich-Alexander-Universität Erlangen-Nürnberg zur Erlangung des Doktorgrads Dr. rer. nat. vorgelegt von Kerstin Fehn Als Dissertation genehmigt von der Naturwissenschaftlichen Fakultät der Friedrich-Alexander Universität Erlangen-Nürnberg Tag der mündlichen Prüfung: 24.03.2015 Vorsitzender des Promotionsorgans: Prof. Dr. Jörn Wilms Gutachter/in: Prof. Dr. Gisela Anton Prof. Dr. Ulrich Katz ν Abstract Active galactic nuclei (AGN) are promising candidates for hadronic acceleration. The combination of radio, gamma ray and neutrino data should give information on their properties, especially concerning the sources of the high-energetic cosmic rays. Assuming a temporal correlation of gamma and neutrino emission in AGN the background of neutrino telescopes can be reduced using gamma ray lightcurves. Thereby the sensitivity for discovering cosmic neutrino sources is enhanced. In the present work a stacked search for a group of AGN with the ANTARES neutrino telescope in the Mediterranean is presented. The selection of AGN is based on the source sample of TANAMI, a multiwavelength observation program (radio to gamma rays) of extragalactic jets southerly of −30◦ declination. In the analysis lightcurves of the gamma satellite Fermi are used. In an unbinned maximum likelihood approach the test statistic in the background only case and in the signal and background case is determined. For the investigated 10% of data of ANTARES within the measurement time between 01.09.2008 and 30.07.2012 no significant excess is observed.
    [Show full text]
  • Nuclear Physics
    Nuclear Physics Overview One of the enduring mysteries of the universe is the nature of matter—what are its basic constituents and how do they interact to form the properties we observe? The largest contribution by far to the mass of the visible matter we are familiar with comes from protons and heavier nuclei. The mission of the Nuclear Physics (NP) program is to discover, explore, and understand all forms of nuclear matter. Although the fundamental particles that compose nuclear matter—quarks and gluons—are themselves relatively well understood, exactly how they interact and combine to form the different types of matter observed in the universe today and during its evolution remains largely unknown. Nuclear physicists seek to understand not just the familiar forms of matter we see around us, but also exotic forms such as those that existed in the first moments after the Big Bang and that exist today inside neutron stars, and to understand why matter takes on the specific forms now observed in nature. Nuclear physics addresses three broad, yet tightly interrelated, scientific thrusts: Quantum Chromodynamics (QCD); Nuclei and Nuclear Astrophysics; and Fundamental Symmetries: . QCD seeks to develop a complete understanding of how the fundamental particles that compose nuclear matter, the quarks and gluons, assemble themselves into composite nuclear particles such as protons and neutrons, how nuclear forces arise between these composite particles that lead to nuclei, and how novel forms of bulk, strongly interacting matter behave, such as the quark-gluon plasma that formed in the early universe. Nuclei and Nuclear Astrophysics seeks to understand how protons and neutrons combine to form atomic nuclei, including some now being observed for the first time, and how these nuclei have arisen during the 13.8 billion years since the birth of the cosmos.
    [Show full text]
  • Dissertation Imaging Single Barium Atoms in Solid Xenon for Barium
    Dissertation Imaging Single Barium Atoms in Solid Xenon for Barium Tagging in the nEXO Neutrinoless Double Beta Decay Experiment Submitted by Timothy Walton Department of Physics In partial fulfillment of the requirements For the Degree of Doctor of Philosophy Colorado State University Fort Collins, Colorado Spring 2016 Doctoral Committee: Advisor: William M. Fairbank, Jr. Bruce Berger Alan Van Orden Robert Wilson Copyright by Timothy Walton 2016 All Rights Reserved Abstract Imaging Single Barium Atoms in Solid Xenon for Barium Tagging in the nEXO Neutrinoless Double Beta Decay Experiment The nEXO experiment will search for neutrinoless double beta decay of the isotope 136Xe in a ton-scale liquid xenon time projection chamber, in order to probe the Majorana nature of neutrinos. Detecting the daughter 136Ba of double beta decay events, called barium tagging, is a technique under investigation which would provide a veto for a background-free measurement. This would involve detecting a single barium ion from within a macroscopic volume of liquid xenon. One proposed barium tagging method is to trap the barium ion in solid xenon at the end of a cold probe, and then detect it by its fluorescence in the solid xenon. In this thesis, new studies on the spectroscopy of deposits of Ba and Ba+ in solid xenon are presented. Imaging of barium atoms in solid xenon is demonstrated with sensitivity down to the single atom level. Achievement of this level of sensitivity is a major step toward barium tagging by this method. ii Acknowledgements I thank my adviser William M. Fairbank, Jr. with inadequate words for his inspiring courage, foresight, and intuition as a physicist.
    [Show full text]
  • THE BOREXINO IMPACT in the GLOBAL ANALYSIS of NEUTRINO DATA Settore Scientifico Disciplinare FIS/04
    UNIVERSITA’ DEGLI STUDI DI MILANO DIPARTIMENTO DI FISICA SCUOLA DI DOTTORATO IN FISICA, ASTROFISICA E FISICA APPLICATA CICLO XXIV THE BOREXINO IMPACT IN THE GLOBAL ANALYSIS OF NEUTRINO DATA Settore Scientifico Disciplinare FIS/04 Tesi di Dottorato di: Alessandra Carlotta Re Tutore: Prof.ssa Emanuela Meroni Coordinatore: Prof. Marco Bersanelli Anno Accademico 2010-2011 Contents Introduction1 1 Neutrino Physics3 1.1 Neutrinos in the Standard Model . .4 1.2 Massive neutrinos . .7 1.3 Solar Neutrinos . .8 1.3.1 pp chain . .9 1.3.2 CNO chain . 13 1.3.3 The Standard Solar Model . 13 1.4 Other sources of neutrinos . 17 1.5 Neutrino Oscillation . 18 1.5.1 Vacuum oscillations . 20 1.5.2 Matter-enhanced oscillations . 22 1.5.3 The MSW effect for solar neutrinos . 26 1.6 Solar neutrino experiments . 28 1.7 Reactor neutrino experiments . 33 1.8 The global analysis of neutrino data . 34 2 The Borexino experiment 37 2.1 The LNGS underground laboratory . 38 2.2 The detector design . 40 2.3 Signal processing and Data Acquisition System . 44 2.4 Calibration and monitoring . 45 2.5 Neutrino detection in Borexino . 47 2.5.1 Neutrino scattering cross-section . 48 2.6 7Be solar neutrino . 48 2.6.1 Seasonal variations . 50 2.7 Radioactive backgrounds in Borexino . 51 I CONTENTS 2.7.1 External backgrounds . 53 2.7.2 Internal backgrounds . 54 2.8 Physics goals and achieved results . 57 2.8.1 7Be solar neutrino flux measurement . 57 2.8.2 The day-night asymmetry measurement . 58 2.8.3 8B neutrino flux measurement .
    [Show full text]
  • Neurychlovacová Fyzika Elementárních Cástic
    Czech contribution to neutrino experiments V. Vorobel Charles University in Prague, FMP • Direct neutrino mass measurement – KATRIN • Accelerator neutrino NOvA • Reactor neutrino – Daya Bay, JUNO • Sterile neutrino DANCE • Doublel beta decay – NEMO3, SuperNEMO • Small scale experiments TGV 27.3.2015 RECFA - Vít Vorobel 1 KATRIN experiment - model independent search for the neutrino mass Czech participant: Nuclear Physics Institute of the Czech Acad. Sci., Řež near Prague Local and KATRIN websites: http://ojs.ujf.cas.cz/katrin/ http://www.katrin.kit.edu/ 2 KATRIN - Karlsruhe Tritium Neutrino Experiment: direct β-spectroscopic search for mν Measured quantity : 2 2 2 mνe = Σ|Uei| · mi i Mass eigenstates Neutrino mixing matrix elements theoretical decay amplitude: 2 1/2 dN/dE = K × F(Ee, Z+1) × pe × (Ee+me) × (E0-Ee) × [ (E0-Ee)2 – mνe ] Sensitiviy after 1000 measuring days: mν < 0.2 eV at 90 % C.L. if no effect is observed 3 mν = 0.35 eV would be seen as 5σ effect KATRIN setup - with MAC-E filter spectrometers For sensitivity of 200 meV: -high resolution: 0.9 eV -high luminosity: 19% of 4p -low detector back.: 10 mHz -T2 injection of 40 g/day, 4.7 Ci/s -1000 measurement days -high stability of key parameters e.g.: ± 3 ppm for retar. HV calibration & monitoring electron sources are developed at NPI 4 KATRIN – NPI: relations, manpower, funding, tasks With institutions from Germany, Russia, USA NPI is a founder of KATRIN Solid O. Dragoun and D. Vénos are members of the KATRIN Collaboration Board Electron D. Venos is co-leader of the task Calibration and Monitoring source Collaborators in 2014 .
    [Show full text]
  • RES-NOVA Sensitivity to Core-Collapse and Failed Core-Collapse Supernova Neutrinos
    Prepared for submission to JCAP RES-NOVA sensitivity to core-collapse and failed core-collapse supernova neutrinos L. Pattavinaa;b;1 N. Ferreiro Iachellinic;1 L. Pagnaninia;d L. Canonicac E. Celib;d M. Clemenzae F. Ferronid;f E. Fiorinie A. Garaic L. Gironie M. Mancusoc S. Nisia F. Petriccac S. Pirroa S. Pozzie A. Puiua;d J. Rotheb S. Schönertb L. Shtembaric R. Straussb V. Wagnerb aINFN Laboratori Nazionali del Gran Sasso, 67100 Assergi, Italy bPhysik-Department and Excellence Cluster Origins, Technische Universität München, 85747 Garching, Germany arXiv:2103.08672v2 [astro-ph.IM] 16 Aug 2021 cMax-Planck-Institut für Physik, 80805 München, Germany dGran Sasso Science Institute, 67100, L’Aquila, Italy eINFN Sezione Milano - Bicocca and Dipartimento di Fisica, Università di Milano - Bicocca, 20126 Milano, Italy f INFN Sezione di Roma1, 00185, Roma, Italy 1Corresponding authors. E-mail: [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], ettore.fi[email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected] Abstract. RES-NOVA is a new proposed experiment for the investigation of astrophysical neutrino sources with archaeological Pb-based cryogenic detectors. RES-NOVA will exploit Coherent Elastic neutrino-Nucleus Scattering (CEνNS) as detection channel, thus it will be equally sensitive to all neutrino flavors produced by Supernovae (SNe).
    [Show full text]
  • Letter of Interest Direct Neutrino-Mass Measurements with KATRIN
    Snowmass2021 - Letter of Interest Direct Neutrino-Mass Measurements with KATRIN NF Topical Groups: (check all that apply /) (NF1) Neutrino oscillations (NF2) Sterile neutrinos (NF3) Beyond the Standard Model (NF4) Neutrinos from natural sources (NF5) Neutrino properties (NF6) Neutrino cross sections (NF7) Applications (TF11) Theory of neutrino physics (NF9) Artificial neutrino sources (NF10) Neutrino detectors (Other) [Please specify frontier/topical group(s)] Contact Information: Diana Parno (Carnegie Mellon University) [email protected] Collaboration: KATRIN Authors: The full author list follows the text and references. Abstract: (maximum 200 words) The Karlsruhe Tritium Neutrino-Mass (KATRIN) experiment has re- cently set the world’s best direct limit on the neutrino mass, from the measurement of the electron energy spectrum of tritium β-decay near its endpoint. This first result is based on the equivalent of only 9 days of data-taking in the experiment’s design configuration. Here, we discuss KATRIN’s plans for further ex- ploring the neutrino mass in the next 1000 days of data-taking, including research and development toward still-greater sensitivities. 1 The neutrino-mass scale is one of the most pressing open questions in particle physics, affecting not only neutrino theory within the Standard Model, but also the possible rates of neutrinoless double-beta decay and structure formation in the early universe. Cosmological observations have set extremely tight constraints P on the sum of neutrino-mass values mi, recently reporting mi < 0.26 eV (95% confidence level, CL) from cosmic-microwave-background power spectra alone [1]. However, the interpretation of these limits implicitly relies upon the paradigm of the cosmological standard model.
    [Show full text]