A5039498194- Atomic and Subatomic Physics Research
- Dark Matter and Cosmic Phenomena
- Particle physics theoretical and experimental studies
- Muon and positron interactions and applications
- Atomic and Molecular Physics
- Quantum, superfluid, helium dynamics
- Neutrino Physics Research
- Particle Detector Development and Performance
- Particle accelerators and beam dynamics
- Nuclear physics research studies
- Cold Atom Physics and Bose-Einstein Condensates
- Radiation Detection and Scintillator Technologies
- Nuclear Physics and Applications
- Astronomy and Astrophysical Research
- Experimental and Theoretical Physics Studies
- Gamma-ray bursts and supernovae
- Quantum Chromodynamics and Particle Interactions
- X-ray Spectroscopy and Fluorescence Analysis
- Astrophysics and Cosmic Phenomena
- Flexible and Reconfigurable Manufacturing Systems
- Cosmology and Gravitation Theories
- Solid State Laser Technologies
- Corporate Governance and Management
- Advanced Chemical Physics Studies
- Noncommutative and Quantum Gravity Theories
Paul Scherrer Institute
2015-2024
ETH Zurich
1987-2023
Istituto Nazionale di Fisica Nucleare, Sezione di Pisa
2022-2023
Suranaree University of Technology
2023
University of Washington
2010-2022
Shanghai Jiao Tong University
2022
European Organization for Nuclear Research
2012-2022
University of Pisa
2022
Johannes Gutenberg University Mainz
2021-2022
University of Zurich
1977-2021
Fifteen months of cumulative CoGeNT data are examined for indications an annual modulation, a predicted signature weakly interacting massive particle (WIMP) interactions. Presently available support the presence modulated component unknown origin, with parameters prima facie compatible galactic halo composed light-mass WIMPs. Unoptimized estimators yield statistical significance modulation ∼2.8σ, limited by short exposure.
We present the result of an experiment to measure electric dipole moment (EDM) neutron at Paul Scherrer Institute using Ramsey's method separated oscillating magnetic fields with ultracold neutrons (UCN). Our measurement stands in long history EDM experiments probing physics violating time reversal invariance. The salient features this were use a Hg-199 co-magnetometer and array optically pumped cesium vapor magnetometers cancel correct for field changes. statistical analysis was performed...
CoGeNT employs p-type point-contact (PPC) germanium detectors to search for Weakly Interacting Massive Particles (WIMPs). By virtue of its low energy threshold and ability reject surface backgrounds, this type device allows an emphasis on low-mass dark matter candidates (wimp mass about 10 GeV/c2). We report the characteristics PPC detector presently taking data at Soudan Underground Laboratory, elaborating aspects shielding, acquisition, instrumental stability, analysis, background...
The M ajorana D emonstrator will search for the neutrinoless double-beta<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M1"><mml:mo stretchy="false">(</mml:mo><mml:mi>β</mml:mi><mml:mi>β</mml:mi><mml:mfenced separators="|"><mml:mrow><mml:mn fontstyle="italic">0</mml:mn><mml:mi>ν</mml:mi></mml:mrow></mml:mfenced><mml:mo stretchy="false">)</mml:mo></mml:math>decay of isotope<mml:math id="M2"/>Ge with a mixed array enriched and natural germanium detectors. observation this rare...
The Majorana Collaboration is operating an array of high purity Ge detectors to search for neutrinoless double-β decay in ^{76}Ge. Demonstrator comprises 44.1 kg (29.7 enriched ^{76}Ge) split between two modules contained a low background shield at the Sanford Underground Research Facility Lead, South Dakota. Here we present results from data taken during construction, commissioning, and start full operations. We achieve unprecedented energy resolution 2.5 keV FWHM Q_{ββ} very with no...
Abstract The energy levels of hydrogen-like atomic systems can be calculated with great precision. Starting from their quantum mechanical solution, they have been refined over the years to include electron spin, relativistic and field effects, tiny shifts related complex structure nucleus. These caused by nuclear are vastly magnified in formed a negative muon nucleus, so spectroscopy these muonic ions used investigate high Here we present measurement two 2S–2P transitions helium-4 ion that...
A neutron $\ensuremath{\beta}$-decay asymmetry measurement using polarized ultracold neutrons (UCN) determines the correlation between spin of and momentum decay electron. The authors extract ratio weak axial-vector to vector couplings with reduced uncertainties. This new result from first this UCN contributes a benchmark for lattice QCD calculations possibility improved precision on CKM matrix element ${V}_{u\phantom{\rule{0}{0ex}}d}$ $\ensuremath{\beta}$ decay.
The Mu3e experiment aims to find or exclude the lepton flavour violating decay $\mu \rightarrow eee$ at branching fractions above $10^{-16}$. A first phase of using an existing beamline Paul Scherrer Institute (PSI) is designed reach a single event sensitivity $2\cdot 10^{-15}$. We present overview all aspects technical design and expected performance phase~I detector. high rate up $10^{8}$ muon decays per second low momenta electrons positrons pose unique set challenges, which we tackle...
We propose an experiment to measure the nuclear charge radii of light elements with up 20~times higher accuracy. These are essential both for understanding physics at low energies, and experimental theoretical applications in simple atomic systems. Such comparisons advance bound-state quantum electrodynamics useful searching new beyond Standard Model. The energy levels muonic atoms highly susceptible structure, especially mean square radius. lightest nuclei (with number, $Z=1,2$) have been...
A new measurement of the neutron $β$-decay asymmetry $A_0$ has been carried out by UCNA collaboration using polarized ultracold neutrons (UCN) from solid deuterium UCN source at Los Alamos Neutron Science Center (LANSCE). Improvements in experiment have led to reductions both statistical and systematic uncertainties leading $A_0 = -0.11954(55)_{\rm stat.}(98)_{\rm syst.}$, corresponding ratio axial-vector vector coupling $λ\equiv g_A/g_V -1.2756(30)$.
Abstract The precise measurement of forces is one way to obtain deep insight into the fundamental interactions present in nature. In context neutral antimatter, gravitational interaction high interest, potentially revealing new that violate weak equivalence principle. Here we report on a successful extension tool from atom optics—the moiré deflectometer—for acceleration slow antiprotons. setup consists two identical transmission gratings and spatially resolving emulsion detector for...
Weakly Interacting Massive Particles (WIMPs) are well-established dark matter candidates. WIMP interactions with sensitive detectors expected to display a characteristic annual modulation in rate. We release dataset spanning 3.4 years of operation from low-background germanium detector, designed search for this signature. A previously reported persists, concentrated region the energy spectrum populated by an exponential excess unknown origin. Its phase and period agree phenomenological...
In case a mirror world with copy of our ordinary particle spectrum would exist, the neutron n and its degenerate partner, n', could potentially mix undergo nn' oscillations. The interaction an magnetic field lift degeneracy between partners, diminish n' amplitude in wave function and, thus, suppress observability. We report experimental comparison ultracold storage trap without superimposed field. No influence is found assuming negligible fields, limit on oscillation time taunn' > 103 s (95%...
A clock comparison experiment, analyzing the ratio of spin precession frequencies stored ultracold neutrons and 199Hg atoms, is reported. No daily variation this could be found, from which set an upper limit on Lorentz invariance violating cosmic anisotropy field b perpendicular < 2 x 10(-20) eV (95% C.L.). This first for free neutron. result also interpreted as a direct gravitational dipole moment neutron |gn| 0.3 eV/c2 m spin-dependent interaction with Sun. Analyzing Earth, based previous...
CoGeNT has taken data for over 3 years, with 1136 live days of accumulated as April 23, 2013. We report on the results a maximum likelihood analysis to extract any possible dark matter signal present in collected data. The extraction uses 2-dimensional probability density functions (PDFs) characterize anticipated variations interaction rates given observable nuclear recoil energies during differing periods Earth's annual orbit around Sun. Cosmogenic and primordial radioactivity backgrounds...
The CREMA collaboration is pursuing a measurement of the ground-state hyperfine splitting (HFS) in muonic hydrogen ( \mu <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>μ</mml:mi></mml:math> p) with 1 ppm accuracy by means pulsed laser spectroscopy to determine two-photon-exchange contribution 2\times10^{-4}...
Muonic atom spectroscopy is a method that can determine absolute nuclear charge radii with typical relative precision of $$10^{-3}$$ . Recent developments have enabled to extend muonic microscopic target quantities as low $$5\,{\upmu }\text {g}$$ This substantial reduction from the traditional limit order $$100\,\text {mg}$$ based on transfer mechanism in high-pressure hydrogen gas cell, which transports muon surface material rather than stopping it over broad depth range. approach enables...
We performed ultracold neutron storage measurements to search for additional losses due (n) mirror-neutron (n′) oscillations as a function of an applied magnetic field B. In the presence mirror B′, would be maximal B≈B′. did not observe any indication nn′ and placed lower limit on oscillation time τnn′>12.0 s at 95% C.L. B′ between 0 12.5 μT.Received 26 May 2009DOI:https://doi.org/10.1103/PhysRevD.80.032003©2009 American Physical Society
The measurement of the neutron electric dipole moment (nEDM) constrains contribution CP-violating terms within both Standard Model and its extensions. experiment uses ultracold neutrons (UCN) stored in vacuum at room temperature. This technique provided last (and best) limit by RAL/Sussex/ILL collaboration 2006: dn < 2:9 × 10-26 e cm (90% C.L.). We aim to improve experimental sensitivity a factor 5 2-3 years, using an upgrade same apparatus. will take advantage increased density Paul...
It has been proposed recently that a previously unobserved neutron decay branch to dark matter particle ($\ensuremath{\chi}$) could account for the discrepancy in lifetime observed experiments use two different measurement techniques. One of possible final states discussed includes single $\ensuremath{\chi}$ along with an ${e}^{+}{e}^{\ensuremath{-}}$ pair. We data from UCNA (Ultracold Neutron Asymmetry) experiment set limits on this channel. Coincident electron-like events are detected...
This letter of intent proposes an experiment to search for electric dipole moment the muon based on frozen-spin technique. We intend exploit high field, $E=1{\rm GV/m}$, experienced in rest frame with a momentum $p=125 {\rm MeV/}c$ when passing through large magnetic field $|\vec{B}|=3{\rm T}$. Current fluxes at $μ$E1 beam line permit improved sensitivity $σ(d_μ)\leq 6\times10^{-23}e{\rm cm}$, about three orders magnitude more than current upper limit $|d_μ|\leq1.8\times10^{-19}e{\rm...