The multi-staged XENON program at INFN Laboratori Nazionali del Gran Sasso aims to detect dark matter with two-phase liquid xenon time projection chambers of increasing size and sensitivity. The XENONnT experiment is the latest detector in the program, planned to be an upgrade of its predecessor XENON1T. It features an active target of 5.
View Article and Find Full Text PDFWe present a new measurement of the positive muon magnetic anomaly, a_{μ}≡(g_{μ}-2)/2, from the Fermilab Muon g-2 Experiment using data collected in 2019 and 2020. We have analyzed more than 4 times the number of positrons from muon decay than in our previous result from 2018 data. The systematic error is reduced by more than a factor of 2 due to better running conditions, a more stable beam, and improved knowledge of the magnetic field weighted by the muon distribution, ω[over ˜]_{p}^{'}, and of the anomalous precession frequency corrected for beam dynamics effects, ω_{a}.
View Article and Find Full Text PDFMultiple viable theoretical models predict heavy dark matter particles with a mass close to the Planck mass, a range relatively unexplored by current experimental measurements. We use 219.4 days of data collected with the XENON1T experiment to conduct a blind search for signals from multiply interacting massive particles (MIMPs).
View Article and Find Full Text PDFTRIUMF is one of the only laboratories in the world able to produce both lead-203 (Pb, t = 51.9 h) and Pb (t = 10.6 h) onsite via its 13 and 500 MeV cyclotrons, respectively.
View Article and Find Full Text PDFConditional gene regulation in Drosophila through binary expression systems like the LexA-LexAop system provides a superb tool for investigating gene and tissue function. To increase the availability of defined LexA enhancer trap insertions, we present molecular, genetic, and tissue expression studies of 301 novel Stan-X LexA enhancer traps derived from mobilization of the index SX4 line. This includes insertions into distinct loci on the X, II, and III chromosomes that were not previously associated with enhancer traps or targeted LexA constructs, an insertion into ptc, and seventeen insertions into natural transposons.
View Article and Find Full Text PDFWe report on a blinded analysis of low-energy electronic recoil data from the first science run of the XENONnT dark matter experiment. Novel subsystems and the increased 5.9 ton liquid xenon target reduced the background in the (1, 30) keV search region to (15.
View Article and Find Full Text PDFThe selection of low-radioactive construction materials is of the utmost importance for rare-event searches and thus critical to the XENONnT experiment. Results of an extensive radioassay program are reported, in which material samples have been screened with gamma-ray spectroscopy, mass spectrometry, and Rn emanation measurements. Furthermore, the cleanliness procedures applied to remove or mitigate surface contamination of detector materials are described.
View Article and Find Full Text PDFIn this work, an efficient 3-step process targeting the chemical modification and purification of lignin oligomers from industrial alkaline lignin is described. The oxidative depolymerization process of alkaline lignin with O or Air pressure, without use of metal catalyst, led to the production of two fractions of lignin oligomers named 'precipitated lignin' and 'hydrosoluble lignin' with 40% and 60% yield, respectively. These fractions were characterized with a wide range of methods including NMR spectroscopy (31P, 2D-HSQC), SEC (in basic media), FTIR.
View Article and Find Full Text PDFThe selection of low-radioactive construction materials is of utmost importance for the success of low-energy rare event search experiments. Besides radioactive contaminants in the bulk, the emanation of radioactive radon atoms from material surfaces attains increasing relevance in the effort to further reduce the background of such experiments. In this work, we present the Rn emanation measurements performed for the XENON1T dark matter experiment.
View Article and Find Full Text PDFHemicelluloses were extracted from a softwood acid sulfite pulp in a three-step procedure. Further delignification step resulted in a holocellulose pulp containing only 1.7 wt.
View Article and Find Full Text PDFWe present the first results of the Fermilab National Accelerator Laboratory (FNAL) Muon g-2 Experiment for the positive muon magnetic anomaly a_{μ}≡(g_{μ}-2)/2. The anomaly is determined from the precision measurements of two angular frequencies. Intensity variation of high-energy positrons from muon decays directly encodes the difference frequency ω_{a} between the spin-precession and cyclotron frequencies for polarized muons in a magnetic storage ring.
View Article and Find Full Text PDFWe report on a search for nuclear recoil signals from solar ^{8}B neutrinos elastically scattering off xenon nuclei in XENON1T data, lowering the energy threshold from 2.6 to 1.6 keV.
View Article and Find Full Text PDFThe electrically insulating space layer takes a fundamental role in monolithic carbon-graphite based perovskite solar cells (PSCs) and it has been established to prevent the charge recombination of electrons at the mp-TiO/carbon-graphite (CG) interface. Thick 1 μm printed layers are commonly used for this purpose in the established triple-mesoscopic structures to avoid ohmic shunts and to achieve a high open circuit voltage. In this work, we have developed a reproducible large-area procedure to replace this thick space layer with an ultra-thin dense 40 nm sputtered AlO which acts as a highly electrically insulating layer preventing ohmic shunts.
View Article and Find Full Text PDFDirect dark matter detection experiments based on a liquid xenon target are leading the search for dark matter particles with masses above ∼5 GeV/c^{2}, but have limited sensitivity to lighter masses because of the small momentum transfer in dark matter-nucleus elastic scattering. However, there is an irreducible contribution from inelastic processes accompanying the elastic scattering, which leads to the excitation and ionization of the recoiling atom (the Migdal effect) or the emission of a bremsstrahlung photon. In this Letter, we report on a probe of low-mass dark matter with masses down to about 85 MeV/c^{2} by looking for electronic recoils induced by the Migdal effect and bremsstrahlung using data from the XENON1T experiment.
View Article and Find Full Text PDFWe report constraints on light dark matter (DM) models using ionization signals in the XENON1T experiment. We mitigate backgrounds with strong event selections, rather than requiring a scintillation signal, leaving an effective exposure of (22±3) tonne day. Above ∼0.
View Article and Find Full Text PDFFishes are exposed to mixtures of different classes of steroids, but ecotoxicological implications are not sufficiently known. Here, we systematically analyze effects of different combinations of steroid mixtures in zebrafish embryos to assess their joint activities on physiology and transcriptional alterations of steroid-specific target genes at 96 and 120 h post fertilization. In binary mixtures of clobetasol propionate (CLO) with estradiol (E2) or androstenedione (A4), each steroid exhibited its own expression profile.
View Article and Find Full Text PDFWe report the first experimental results on spin-dependent elastic weakly interacting massive particle (WIMP) nucleon scattering from the XENON1T dark matter search experiment. The analysis uses the full ton year exposure of XENON1T to constrain the spin-dependent proton-only and neutron-only cases. No significant signal excess is observed, and a profile likelihood ratio analysis is used to set exclusion limits on the WIMP-nucleon interactions.
View Article and Find Full Text PDFPhys Rev Lett
February 2019
We present first results on the scalar coupling of weakly interacting massive particles (WIMPs) to pions from 1 t yr of exposure with the XENON1T experiment. This interaction is generated when the WIMP couples to a virtual pion exchanged between the nucleons in a nucleus. In contrast to most nonrelativistic operators, these pion-exchange currents can be coherently enhanced by the total number of nucleons and therefore may dominate in scenarios where spin-independent WIMP-nucleon interactions are suppressed.
View Article and Find Full Text PDFIntroduction: Intensive treatment aimed at achieving optimal metabolic control to prevent the development of chronic diabetic complications is often associated with an increased rate of hypoglycemic events. Hypoglycemia is believed to be responsible for acute fatal and nonfatal cardiovascular events likely as a consequence of the activation of pro-inflammatory and pro-atherothrombotic pathways. Hypoglycemia has been reported to influence the development of preclinical atherosclerosis.
View Article and Find Full Text PDFRelating crystallization of the absorber layer in a perovskite solar cell (PSC) to the device performance is a key challenge for the process development and in-depth understanding of these types of high efficient solar cells. A novel approach that enables real-time photo-physical and electrical characterization using a graphite-based PSC is introduced in this work. In our graphite-based PSC, the device architecture of porous monolithic contact layers creates the possibility to perform photovoltaic measurements while the perovskite crystallizes within this scaffold.
View Article and Find Full Text PDFACS Appl Mater Interfaces
September 2017
The most efficient organic-inorganic perovskite solar cells (PSCs) contain the conventional n-i-p mesoscopic device architecture using a semiconducting TiO scaffold combined with a compact TiO blocking layer for selective electron transport. These devices achieve high power conversion efficiencies (15-22%) but mainly require high-temperature sintering (>450 °C), which is not possible for temperature-sensitive substrates. Thus far, comparably little effort has been spent on alternative low-temperature (<150 °C) routes to realize high-efficiency TiO-based PSCs; instead, other device architectures have been promoted for low-temperature processing.
View Article and Find Full Text PDFCH3NH3PbI3 perovskite solar cells with a mesoporous TiO2 layer and spiro-MeOTAD as a hole transport layer (HTL) with three different CH3NH3I concentrations (0.032 M, 0.044 M and 0.
View Article and Find Full Text PDFTo verify whether high level of bladder distension may counteract the inhibitory effect of descending pathways on sacral spinal cord neurons and to investigate which spinal circuitries are possibly involved in such a viscero-somatic interaction. Nociceptive withdrawal reflex (NWR), cutaneous silent period (CSP), and H-reflex were recorded in both lower and upper limbs of twenty-eight healthy subjects. Subjects were examined during baseline (empty bladder, no voiding desire), high level of bladder filling (urgency desire), and control (empty bladder, no voiding desire) sessions.
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