J. Hakenmüller
A5043330965- Neutrino Physics Research
- Particle physics theoretical and experimental studies
- Dark Matter and Cosmic Phenomena
- Astrophysics and Cosmic Phenomena
- Radiation Detection and Scintillator Technologies
- Particle Detector Development and Performance
- Nuclear Physics and Applications
- Atomic and Subatomic Physics Research
- Muon and positron interactions and applications
- Nuclear physics research studies
- Radiation Therapy and Dosimetry
- Astro and Planetary Science
- Quantum, superfluid, helium dynamics
- Quantum Chromodynamics and Particle Interactions
- Advanced NMR Techniques and Applications
- Planetary Science and Exploration
- Isotope Analysis in Ecology
- Cosmology and Gravitation Theories
- Electron and X-Ray Spectroscopy Techniques
- Vibration and Dynamic Analysis
- Particle accelerators and beam dynamics
- Nuclear reactor physics and engineering
- Stellar, planetary, and galactic studies
- High-pressure geophysics and materials
- Computational Physics and Python Applications
Max Planck Institute for Nuclear Physics
2016-2025
Duke University
2022-2024
Max Planck Society
2015
The GERmanium Detector Array (GERDA) experiment searched for the lepton-number-violating neutrinoless double-$\beta$ ($0\nu\beta\beta$) decay of $^{76}$Ge, whose discovery would have far-reaching implications in cosmology and particle physics. By operating bare germanium diodes, enriched an active liquid argon shield, GERDA achieved unprecedently low background index $5.2\times10^{-4}$ counts/(keV$\cdot$kg$\cdot$yr) signal region met design goal to collect exposure 100 kg$\cdot$yr a...
The GERDA experiment searches for the lepton-number-violating neutrinoless double-β decay of ^{76}Ge (^{76}Ge→^{76}Se+2e^{-}) operating bare Ge diodes with an enriched fraction in liquid argon. exposure broad-energy germanium type (BEGe) detectors is increased threefold respect to our previous data release. BEGe feature excellent background suppression from analysis time profile detector signals. In window a level 1.0_{-0.4}^{+0.6}×10^{-3} counts/(keV kg yr) has been achieved; if normalized...
A discovery that neutrinos are not the usual Dirac but Majorana fermions, i.e. identical to their antiparticles, would be a manifestation of new physics with profound implications for particle and cosmology. generate neutrinoless double-$\beta$ ($0\nu\beta\beta$) decay, matter-creating process without balancing emission antimatter. So far, 0$\nu\beta\beta$ decay has eluded detection. The GERDA collaboration searches $0\nu\beta\beta$ $^{76}$Ge by operating bare germanium detectors in an...
We report the best limit on coherent elastic scattering of electron antineutrinos emitted from a nuclear reactor off germanium nuclei. The measurement was performed with CONUS detectors positioned at 17.1m 3.9GWth core power plant in Brokdorf, Germany. antineutrino energies less than 10 MeV assure interactions fully regime. analyzed dataset includes 248.7 kgd turned and background data 58.8 off. With quenching parameter k = 0.18 for germanium, we determined an upper number neutrino events 85...
A bstract The measurements of coherent elastic neutrino-nucleus scattering (CE ν NS) experiments have opened up the possibility to constrain neutrino physics beyond standard model elementary particle physics. Furthermore, by considering neutrino-electron in keV-energy region, it is possible set additional limits on new processes. Here, we present constraints that are derived from Conus germanium data (BSM) processes like tensor and vector non-standard interactions (NSIs) neutrino-quark...
The CONUS experiment studies coherent elastic neutrino-nucleus scattering in four 1 kg germanium spectrometers. Low ionization energy thresholds of 210 eV were achieved. detectors operated inside an optimized shield at the Brokdorf nuclear power plant which provided a reactor antineutrino flux up to <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"...
The GERDA collaboration is performing a sensitive search for neutrinoless double beta decay of $^{76}$Ge at the INFN Laboratori Nazionali del Gran Sasso, Italy. upgrade experiment from Phase I to II has been concluded in December 2015. first data release shows that goal suppress background by one order magnitude compared achieved. thus will remain background-free up its design exposure (100 kg yr). It reach thereby half-life sensitivity more than 10$^{26}$ yr within 3 years collection. This...
CONUS is a novel experiment aiming at detecting elastic neutrino nucleus scattering in the fully coherent regime using high-purity Germanium (Ge) detectors and reactor as antineutrino ($\bar\nu$) source. The detector setup installed commercial nuclear power plant Brokdorf, Germany, very small distance to core order guarantee high flux of more than 10$^{13}\bar\nu$/(s$\cdot$cm$^2$). For experiment, good understanding neutron-induced background events required, neutron recoil signals can mimic...
Abstract This article reports the measurement of ionization quenching factor in germanium for nuclear recoil energies keV range. Precise knowledge this energy range is highly relevant coherent elastic neutrino-nucleus scattering and low mass dark matter searches with germanium-based detectors. Nuclear recoils were produced a thin high-purity target very threshold via irradiation using monoenergetic neutron beams. The dependence was directly measured kinematically constrained coincidences...
Abstract We report first constraints on electromagnetic properties of neutrinos from neutrino-electron scattering using data obtained the CONUS germanium detectors, i.e. an upper limit effective neutrino magnetic moment and millicharge. The electron antineutrinos are emitted 3.9 $$\hbox {GW}_\mathrm {th}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mtext>GW</mml:mtext> <mml:mi>th</mml:mi> </mml:msub> </mml:math> reactor core Brokdorf Nuclear Power Plant in...
Abstract Point-contact p-type high-purity germanium detectors (PPC HPGe) are particularly suited for detection of sub-keV nuclear recoils from coherent elastic scattering neutrinos or light dark matter particles. While these particles expected to interact homogeneously in the entire detector volume, specific classes external background radiation preferably deposit their energy close semi-active surface, which diffusion processes dominate that subsequently lead slower rising pulses compared...
We report on the development and construction of high-purity germanium spectrometer setup GIOVE (Germanium Inner Outer VEto), recently built now operated at shallow underground laboratory Max-Planck-Institut für Kernphysik, Heidelberg. Particular attention was paid to design a novel passive active shield, aiming efficient rejection environmental muon induced radiation backgrounds. The achieved sensitivity level $$\le $$ 100 $$\upmu Bq kg $$^{-1}$$ for primordial radionuclides from U Th in...
Abstract The CONUS experiment aims to detect coherent elastic neutrino-nucleus scattering (CE $$\nu $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>ν</mml:mi> </mml:math> NS) of reactor antineutrinos on germanium nuclei in the fully regime, continuing this way physics program started at Brokdorf nuclear power plant, Germany. setup is installed plant Leibstadt, Switzerland, a distance 20.7 m from 3.6 GW thermal core. CE NS signature will be measured with same four...
Neutrinos are elementary particles that interact only very weakly with matter. Neutrino experiments therefore usually big, masses on the multi-ton scale. The thresholdless interaction of coherent elastic scattering neutrinos atomic nuclei leads to drastically enhanced rates, allows for much smaller detectors. study this process gives insights into physics beyond Standard Model particle physics. Conus+ experiment was designed first detect neutrino-nucleus in fully regime low-energy produced...
Abstract CONUS is an experiment aiming at detecting coherent elastic neutrino-nucleus scattering (CE $$\nu $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>ν</mml:mi> </mml:math> NS) of reactor antineutrinos on germanium nuclei in the fully regime, continuing physics program conducted Brokdorf nuclear power plant (KBR), Germany. The installed Leibstadt (KKL), Switzerland, a distance 20.7 m from 3.6 GW core, where antineutrino flux $$1.5\cdot 10^{13}$$ <mml:mrow>...
We present the first search for bosonic superweakly interacting massive particles (super-WIMPs) as keV-scale dark matter candidates performed with GERDA experiment. is a neutrinoless double-β decay experiment which operates high-purity germanium detectors enriched in ^{76}Ge an ultralow background environment at Laboratori Nazionali del Gran Sasso (LNGS) of INFN Italy. Searches were pseudoscalar and vector mass region from 60 keV/c^{2} to 1 MeV/c^{2}. No evidence signal was observed, most...
A bstract The GERmanium Detector Array (Gerda) experiment at the Gran Sasso underground laboratory (LNGS) of INFN is searching for neutrinoless double-beta (0 νββ ) decay 76 Ge. technological challenge Gerda to operate in a “background-free” regime region interest (ROI) after analysis cuts full 100 kg · yr target exposure experiment. careful modeling and decomposition full-range energy spectrum essential predict shape composition events ROI around Q ββ 0 search, extract precise measurement...
Using an 185-kg NaI[Tl] array, COHERENT has measured the inclusive electron-neutrino charged-current cross section on ^{127}I with pion decay-at-rest neutrinos produced by Spallation Neutron Source at Oak Ridge National Laboratory. Iodine is one heaviest targets for which low-energy (≤50 MeV) inelastic neutrino-nucleus processes have been measured, and this first measurement of its section. After a five-year detector exposure, reports flux-averaged electron 9.2_{-1.8}^{+2.1}×10^{-40} cm^{2}....
On July 10, 2018 at 21:29 UT extended areas of South-Western Germany were illuminated by a very bright bolide. This fireball was recorded instruments the European Fireball Network (EN). The records enabled complex and precise description this event including prediction impact area. So far six meteorites totaling about 1.23 kg have been found in predicted location for given mass during dedicated searches. first piece 12 g recovered on 24 close to village Renchen (Baden-Württemberg) followed...
Abstract On March 6, 2016 at 21:36:51 UT , extended areas of Upper Austria, Bavaria (Germany) and the southwestern part Czech Republic were illuminated by a very bright bolide. This bolide was recorded instruments in European Fireball Network it enabled complex precise description this event including prediction impact area. So far six meteorites totaling 1473 g have been found predicted The first pieces recovered on 12, field close to village Stubenberg (Bavaria). is weakly shocked (S3)...
The GERmanium Detector Array (Gerda) collaboration searched for neutrinoless double- β decay in 76 Ge using isotopically enriched high purity germanium detectors at the Laboratori Nazionali del Gran Sasso of INFN. After Phase I (2011-2013), experiment benefited from several upgrades, including an additional active veto based on LAr instrumentation and a significant increase mass by point-contact that improved half-life sensitivity II (2015-2019) order magnitude. At core background mitigation...
Abstract A search for Beyond the Standard Model double- β decay modes of 76 Ge has been performed with data collected during Phase II GERmanium Detector Array ( Gerda ) experiment, located at Laboratori Nazionali del Gran Sasso INFN (Italy). Improved limits on decays involving Majorons have obtained, compared to previous experiments Ge, half-life values order 10 23 yr. For first time Lorentz invariance violation effects in obtained. The isotropic coefficient å (3) , which embeds decay,...
Abstract The CONUS experiment is searching for coherent elastic neutrino nucleus scattering of reactor anti-neutrinos with four low-energy threshold point-contact high-purity germanium spectrometers. Excellent background suppression within the region interest below 1 keV (ionization energy) absolutely necessary to enable signal detection. collected data also make it possible set limits on various models regarding beyond standard model physics. These analyses benefit as well from low level...
Abstract The ability to detect liquid argon scintillation light from within a densely packed high-purity germanium detector array allowed the Gerda experiment reach an exceptionally low background rate in search for neutrinoless double beta decay of $${}^{76}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mrow /> <mml:mn>76</mml:mn> </mml:msup> </mml:math> Ge. Proper modeling propagation throughout experimental setup, any origin volume its eventual detection by...