DOCSLIB.ORG

KATRIN Experiment: Frrt Rerultr and Future Prorpectr

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
KATRIN Experiment: Frrt Rerultr and Future Prorpectr KATRIN experiment: frrt rerultr and future prorpectr Alexey Lokhov on behalf of KATRIN collaboration (University of Muenster & INR RAS) 40th International Conference on High Energy Physics Institut für Kernphysik Westfälische Wilhelms-Universität Münster BBBB.... LLLLeeeehhhhnnnneeeerrrrtttt PPPPlllleeeennnnaaaarrrryyyy IIIIVVVV Three wayr to arrerr the abrolute neutrino marr (Planck)rcale 2 0.12 eV ) 4 i 2 c m( 2 + m 2 c ) 2 ( Cosmologyvery sensitive: era of precision cosmology 2 = p Ho 1) ● m 163 ● compares power at different scales use E current sensitivity: ● EXO-200, KamLAND-Zen, GERDA, < 0.1-0.4 eV Search for 0 Sensitive to Majoranam neutrinos, model-dependent, from supernova) LNV 2) ● ( ) < 2 eV (Mainz & Troitsk) Upper limits by ● m( CUORE: Direct neutrino mass determination 3) ● No further assumptions needed, ● Time-of-flight measurements ● Kinematics of weak decays / beta decays, e.g. tritium, best upper limits before KATRIN: N. Aghanim et al. (Planck), (2018), arXiv:1807.06209; M. J. Dolinski, A. W. Poon, and W. Rodejohann, Annual Review of Nuclear and Particle Science 69, 219 (2019); Eur. Phys. J. C 40, 447 (2005); Phys. Rev. D 84, 112003 Tritium -decay ● continuous -spectrum described by Fermi´s Golden Rule, measurement of efective mass m$e) based on kinematic parameterr & energy conrervation 3 d Γ 2 2 2 =C⋅p⋅( E+m )⋅(E −E)⋅ U ⋅ (E −E) −m ⋅F (E ,Z )⋅θ(E − E−m ) e 0 ∑| ei| √ 0 i 0 i dE i=1 3 2 2 m(e )≝ |U ei|⋅mi ) ∑ s i=1 t √ i n 6 u . b r a ( e 4 t a r t n u 2 o c 0 5 10 15 electron energy (keV) 3 Tritium -decay 3 ● continuous Need:Need: ß-spectrumlowlow endpoint endpoint described energy energy by Fermi´s Golden Rule, TritiumTritium measurement 3HH –– 18.6 18.6 ofkeV keV short half-life (superallowed) – 12.3 yr efective massshort m$ ehalf-life) based (superallowed)on kinematic parameterr & energy conrervation– 12.3 yr dΓ 163 i C p (E m )(E E) (E E)2 m2 ((F163(HoHoE, electron Zelectron)θ (E capture) capture) E m ) dE e 0 0 i 0 i veryvery high high energy energy resolution resolution & & 3 m( ) U 2 m2 veryvery high high luminosity luminositye & & ei i MAC-E-FilterMAC-E-Filter KATRINKATRIN ) i1 s t cryogenic bolometers i cryogenic bolometers n 6 u very low background ECHo, HOLMES very low background ECHo, HOLMES . b CRES PROJECT 8 r CRES PROJECT 8 a ( e 4 t graphene substrate of T target+TES+... PTOLEMY a graphene substrate of T target+TES+... PTOLEMY r t n u 2 o c 0 5 10 15 electron energy (keV) 4 The KATRIN experiment at Karlrruhe Inrtitute of Technology Gaseous T2 source Transport section Pre-Spectrometer Main Spectrometer Detector s c i t keV s E > 10 o n g a i D 70 m 5 The KATRIN Windowlerr Gareour Molecular Tritium Source beam tube Ø = 9 cm , L = 10 m temperature T = 30 K ± 30 mK, can be adjusted in the range 30-110 K guiding field 2.52 T T flow rate 5·1019 molecules/s (40 g of T / day) 2 2 T2 purity 95% ± 0.1 % -3 T2 inlet pressure 10 mbar ± 0.1 % 17 2 11 column density 5·10 T2/cm luminosity 1.7·10 Bq 6 MAC-E-Filter: high-rerolution - rpectrorcopy Magnetic Adiabatic Collimation & Electrostatic Filter: Analyzing plane electrode Giant spectrometer: solenoid solenoid high energy resolution & acceptance U0 Us detector B Bmax Bs min µ = E / B = const. ┴ adiabatic conversion E → E ┴ ‖ Inner electrode system: Momentum transformation without the E-field background suppression & potential shaping 7 Beta spectrum: R Model of the experimental rpectrum (E,m 2 ( e )) Experimental response: f(E-qU) Ä Calibration with electron 83m E gun and Kr conversion 0 NeutrinoNeutrino physicsphysics –– PosterPoster electrons E M.M. SefcikSefcik single0 tritium scan and fit 8 Firrt Tritium (2-week engineering run in 2018) systematic uncertainty ± 0.1% reference First Tritium: ● low tritium concentration: ~1% DT and ~99% D2 ● functionality of all system components at nominal column density rd (5∙1017 cm-2) ● stability of the source parameters → sub per mille level KATRIN Collab, EPJ C 80 (2020) 264 9 KATRIN neutrino marr run # 1 4-week long measuring campaign in spring 2019 with high-purity tritium ● April 10 – May, 13 2019: 780 h ● high-purity tritium (eT = 97.5 % by laser-Raman spectr.) ● high source activity (22% nominal): 10 2.45 ∙ 10 Bq ● high-quality data collected ● full analysis chain using two independent methods + Bayesian 10 Tritium rcanning rtrategy 274 scans of tritium -spectrum: 22 HV set points 5 HV set points ● alternating up- / down- scans ● 2 h net scanning time single tritium scan E0 ● analysis: 27 HV set points and fit ● [ E0 – 40 eV , E0 + 50 eV] still limited bg-slope Measurement point distribution maximizes -mass sensitivity ● focus on region close to E0 11 Fitting tritium -decay rpectrum High-statistics -spectrum - 2 million events in in 90-eV-wide interval (522 h of scanning, 274 indiv. scans) - fit with 4 free parameters: 2 m ( ), R , A , E 2 e bg s 0 neutrino mass square m (e) excellent goodness-of-fit c2 = 21.4 for 23 d.o.f. (p-value = 0.56) Bias-free analysis - blinding of FSD - full analysis chain first on MC data sets - final step: unblinded FSD for experimental data KATRIN Collab, Phys. Rev. Lett. 123 (2019) 221802 12 Analyrir methodr and -marr rerult two independent analysis methods to propagate uncertainties & infer parameters - Covariance matrix: covariance matrix + c2-estimator - MC propagation: 105 MC samples + likelihood (-2 ln L) - both methods agree to a few percent -mass and E : best fit results 0 2 +0.9 2 m (e) = -1.0 -1.1 eV KATRIN Collab, Phys. Rev. Lett. 123 (2019) 221802 E0 = (18573.7 ± 0.1) eV → Q-value: (18575.2 ± 0.5) eV E.G. Myers, A. Wagner, H. Kracke, 3 3 B.A. Wesson, → Q-value[ΔM( H, He)]: (18575.72 ± 0.07) eV Phys. Rev. Lett. 114, 013003 (2015) 13 New upper limit on neutrino marr confidence belts: procedures of Lokhov and Tkachov (LT) + Feldman and Cousins (FC) - for this first result we follow the robust LT method - LT yields experimental sensitivity 2 by construction for m (e) < 0 - KATRIN upper limit on neutrino mass: LT m() < 1.1 eV (90% CL) FC m() < 0.8 eV (90% CL) Bayesian m() < 0.9 eV (90% CI) A.V. Lokhov, F.V. Tkachov, Phys. Part. Nucl. 46 (2015) 347 flat prior, m2>0 G. J. Feldman, R. D. Cousins, Phys. Rev. D 57 (1998) 3873 KATRIN Collab, Phys. Rev. Lett. 123 (2019) 221802 14 Sterile neutrino rearcher with KATRIN ● Same data-set as for the neutrino mass ● 3+1 sterile neutrino model ● 2 Grid search in m4, |Ue4| plane ● Neutrino mass fixed to the minimal allowed value from oscillations (0.009 eV) 15 eV-rcale rterile neutrino ● 2 High Dm 41 values: ─ Improve exclusion with respect to DANSS, PROSPECT, STEREO ─ Exclude parameter space of Reactor Anomaly (RAA) ● 2 Low Dm 41 values: ─ Improve on Mainz and Troitsk limit ─ Approaching Neutrino-4 hint ● Probe a large fraction of RAA in future 16 KATRIN rearch for keV rterile neutrinor ● Deep scan $1.6 keV below E0 ) with low-activity commissioning data – Excellent agreement of model and data -3 – Senritivity to mixing of 10 @ m4 = 0.4 keV ● TRISTAN project: – novel multi-pixel Silicon Drift Detector array – large count rater – good energy rerolution Preliminary segmented Si-PIN wafer S. Mertens et al., J.Phys.G 46 (2019) 6, 065203; T. Brunst et al., JINST 14 (2019) 11, P11013 17 Outlook: Background reduction Background reduction spectrometer bake-out successful AP SAP more effective 219Rn retention Volume dependent background rate ● Reduce the volume of the flux upgraded air coil system modified fields configuration „shifted analyzing plane“ (SAP) – factor 2 signal/background improvement – background & calibration & tritium scans Two large air coil systems: background suppression & B-field shaping 18 Outlook: Statur & future planr mass 1 mass 2 mass 3 Calibration and Optimization 2nd neutrino mass campaign ● Extensive study of plasma properties at different ● Measurement time: 31 days gas densities, temperature and boundary ● Gas density: 84% conditions ● Isotopic purity: 98.6% tritium ● Reduced background with shifted analyzing plane ● Source activity: 9.8 · 1010 Bq 3rd neutrino mass campaign finished on ● Total statistics: 4 · 106 Monday, analysis is ongoing » Data soon to be un-blinded 19 Conclurion ● New world-best direct neutrino mass measurment: m < 1.1 eV (90 % C.L.) ● KATRIN is taking data to reach ultimate sensitivity of ~0.2 eV 90 % C.L.) after 5 years ● First constraints on the eV-scale sterile neutrinos ● First search for keV-scale sterile neutrinos ● BSM physics searches ● Next KATRIN run with optimized settings just completed! – reduced background – optimized source confguration Stay tuned for the new results from KATRIN! 20 Thank you for your attention! We acknowledge the support of Helmholtz Associaton (HGF), Ministry for Educaton and esearch BMBF (05A17PM3, 05A17PX3, 05A17VK2, 05A17PDA, and 05A17WO3), Helmholtz Alliance for Astropartcle Physics (HAP), the doctoral school KSETA at KIT, and Helmholtz Young Investgator Group (VH-NG-1055), Max Planck esearch Group (MaxPlanck@TUM), and Deutsche Forschungsgemeinschaf DFG ( esearch Training Groups Grants No. G K 1694, G K 1694 and G K 2149, Graduate School Grant No. GSC 1085-KSETA, and SFB-1258 in Germany ; Ministry of Educaton, Youth and Sport (CANAM- LM2015056, LTT19005) in the Czech epublic; and the Department of Energy through grants DE-FG02-97E 41020, DE-FG02-94E 40818, DE-SC0004036, DE-FG02-97E 41033, DE-FG02-97E 41041, DE-AC02-05CH11231, and DE- SC0011091 in the United States.
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]
  • 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]
  • 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]
  • 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]
  • 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]
  • Optimization of a KATRIN Source Analysis Tool and Investigations of the Potential to Constrain the Relic Neutrino Background
    Optimization of a KATRIN source analysis tool and investigations of the potential to constrain the relic neutrino background Master Thesis of Florian Heizmann At the Department of Physics Institute of Experimental Nuclear Physics Reviewer: Prof. G. Drexlin Second reviewer: Prof. U. Husemann Advisor: Dr. K. Valerius Second advisor: Dr. M. Babutzka January 2015 KIT – University of the State of Baden-Wuerttemberg and National Research Center of the Helmholtz Association www.kit.edu ABSTRACT The KArlsruhe TRItium Neutrino (KATRIN) experiment { currently under con- struction at KIT { will determine the neutrino mass with an unprecedented sensi- tivity of 200 meV at 90 % C.L. by high-precision tritium β-decay spectroscopy. In order to reach this new level of neutrino mass sensitivity it is very important to understand the tritium source properties and the related systematic measurement uncertainties. Therefore, in the scope of this thesis, the electromagnetic design of a source analysis tool is optimized. Furthermore, the unique tritium source opens up the possibility to search for the elusive relic neutrinos, at least to set limits on the local relic neutrino overdensity, in a laboratory experiment. The potential of KATRIN to set those limits is also explored in this thesis. Das KArlsruhe TRItium Neutrino (KATRIN) Experiment { welches sich momen- tan im Aufbau am KIT befindet { ist konstruiert, um mittels hochaufl¨osender β- Zerfall Spektroskopie die Neutrinomasse mit einer bisher unerreichten Sensitivit¨at von 200 meV zu 90 % C.L. zu bestimmen. Das Erreichen dieses Sensitivit¨atsziels erfordert ein detailliertes Verst¨andnis der Eigenschaften der Quelle und der damit verbundenen systematischen Messunsicher- heiten.
    [Show full text]
  • Indirect Detection Constraints on the Scotogenic Dark Matter Model
    Prepared for submission to JCAP Indirect detection constraints on the scotogenic dark matter model T. de Boer,a R. Busse,b A. Kappes,b M. Klasen,a;1 and S. Zeinstraa aInstitut für Theoretische Physik, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Str. 9, 48149 Münster, Germany bInstitut für Kernphysik, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Str. 9, 48149 Münster, Germany Abstract. Radiative seesaw models have the attractive property of providing dark matter candidates in addition to the generation of neutrino masses. Here we present a study of neutrino signals from the annihilation of dark matter particles that have been gravitationally captured in the Sun in the framework of the scotogenic model. We compute expected event rates in the IceCube detector in its 86-string configuration. As fermionic dark matter does not scatter off nucleons due to its singlet nature and therefore does not accumulate in the Sun, we study the case of scalar dark matter with a scan over the parameter space. Due to a naturally small mass splitting between the two neutral scalar components, inelastic scattering processes with nucleons can occur. We find that for most of the parameter space, i.e. for mass splittings below 500 keV, inelastic scattering in the Sun yields IceCube event rates above 10 events per year, whereas direct detection on Earth is sensitive only to 250 keV. Consequently, a detailed analysis with IceCube could lead to a lower limit on the scalar coupling λ 1:6 10 5 m =TeV. For larger mass splittings, only elastic scattering occurs 5 & · − · DM in the Sun.
    [Show full text]
  • Detecting Fast Time Variations in the Supernova Neutrino Flux with Hyper-Kamiokande
    Max-Planck-Institut für Physik Technische Universität München (Werner-Heisenberg-Institut) Fakultät für Physik Abschlussarbeit im Masterstudiengang Physik Detecting Fast Time Variations in the Supernova Neutrino Flux with Hyper-Kamiokande Suche nach hochfrequenten Oszillationen des Supernovaneutrino-Flusses mit Hyper-Kamiokande Jost Migenda 2015-06-22 arXiv:1609.04286v1 [physics.ins-det] 14 Sep 2016 “However big you think supernovae are, they’re bigger than that.” — Donald Spector [1] Themensteller: Prof. Dr. Lothar Oberauer Betreuer: Dr. habil. Georg G. Raffelt Datum des Kolloquiums: 8. Juli 2015 Abstract For detection of neutrinos from galactic supernovae, the planned Hyper- Kamiokande detector will be the first detector that delivers both a high event rate (about one third of the IceCube rate) and event-by-event energy information. In this thesis, we use a three-dimensional computer simulation by the Garching group to find out whether this additional information can be used to improve the detection prospects of fast time variations in the neutrino flux. We find that the amplitude of SASI oscillations of the neutrino number flux is energy-dependent. However, in this simulation, the larger amplitude in some energy bins is not sufficient to counteract the increased noise caused by the lower event rate. Finally, we derive a condition describing when it is advantageous to consider an energy bin instead of the total signal and show that this condition is satisfied if the oscillation of the mean neutrino energy is increased slightly. iii Contents Abstract ........................................ iii 1 Introduction .....................................1 2 Core-Collapse Supernovae ............................5 2.1 Classification of Supernovae . .5 2.1.1 Spectral Classification .
    [Show full text]
  • Measurement of Neutrino Oscillations in Atmospheric Neutrinos with the Icecube Deepcore Detector
    Measurement of neutrino oscillations in atmospheric neutrinos with the IceCube DeepCore detector Dissertation zur Erlangung des akademischen Grades doctor rerum naturalium ( Dr. rer. nat.) im Fach Physik eingereicht an der Mathematisch-Naturwissenschafltichen Fakultät I der Humboldt-Universität zu Berlin von B.Sc. Juan Pablo Yáñez Garza Präsident der Humboldt-Universität zu Berlin: Prof. Dr. Jan-Hendrik Olbertz Dekan der Mathematisch-Naturwissenschaftlichen Fakultät I: Prof. Stefan Hecht, Ph.D. Gutachter: 1. Prof. Dr. Hermann Kolanoski 2. Prof. Dr. Allan Halgren 3. Prof. Dr. Thomas Lohse Tag der mündlichen Prüfung: 02.06.2014 iii Abstract The study of neutrino oscillations is an active Ąeld of research. During the last couple of decades many experiments have measured the efects of oscillations, pushing the Ąeld from the discovery stage towards an era of precision and deeper understanding of the phe- nomenon. The IceCube Neutrino Observatory, with its low energy subarray, DeepCore, has the possibility of contributing to this Ąeld. IceCube is a 1 km3 ice Cherenkov neutrino telescope buried deep in the Antarctic glacier. DeepCore, a region of denser instrumentation in the lower center of IceCube, permits the detection of neutrinos with energies as low as 10 GeV. Every year, thousands of atmospheric neutrinos around these energies leave a strong signature in DeepCore. Due to their energy and the distance they travel before being detected, these neutrinos can be used to measure the phenomenon of oscillations. This work starts with a study of the potential of IceCube DeepCore to measure neutrino oscillations in diferent channels, from which the disappearance of νµ is chosen to move forward.
    [Show full text]