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Euclid preparation. Sensitivity to neutrino parameters
No full textInternational audienceThe Euclid mission of the European Space Agency will deliver weak gravitational lensing and galaxy clustering surveys that can be used to constrain the standard cosmological model and extensions thereof. We present forecasts from the combination of these surveys on the sensitivity to cosmological parameters including the summed neutrino mass and the effective number of relativistic species in the standard CDM scenario and in a scenario with dynamical dark energy (CDM). We compare the accuracy of different algorithms predicting the nonlinear matter power spectrum for such models. We then validate several pipelines for Fisher matrix and MCMC forecasts, using different theory codes, algorithms for numerical derivatives, and assumptions concerning the non-linear cut-off scale. The Euclid primary probes alone will reach a sensitivity of 56meV in the CDM+ model, whereas the combination with CMB data from Planck is expected to achieve 23meV and raise the evidence for a non-zero neutrino mass to at least the level. This can be pushed to a detection if future CMB data from LiteBIRD and CMB Stage-IV are included. In combination with Planck, Euclid will also deliver tight constraints on \Delta N_{\rm eff}< 0.144 (95%CL) in the CDM++ model, or \Delta N_{\rm eff}< 0.063 when future CMB data are included. When floating , we find that the sensitivity to remains stable, while that to degrades at most by a factor 2. This work illustrates the complementarity between the Euclid spectroscopic and imaging/photometric surveys and between Euclid and CMB constraints. Euclid will have a great potential for measuring the neutrino mass and excluding well-motivated scenarios with additional relativistic particles
Electron Paramagnetic Resonance spectroscopy of a scheelite crystal using microwave photon counting
No full textInternational audienceCounting the microwave photons emitted by an ensemble of electron spins when they relax radiatively has recently been introduced as a sensitive new method for electron paramagnetic resonance spectroscopy at millikelvin temperatures. Here, we apply this spin fluorescence method to a scheelite crystal of CaWO4, finding some known (, , and ) and other unknown paramagnetic impurities. Investigating the zero nuclear spin isotope () transition of as a model system, we provide a quantitative analysis of the time-dependent photon counting rate following an excitation pulse, as a function of its power. The achieved signal-to-noise ratio is found to be an order of magnitude higher than the one obtained by inductively-detected Hahn echo under identical conditions. Finally, we use spin fluorescence spectroscopy at low excitation power to probe the properties of rare-earth-ions close to a metallic wire deposited on the surface; our data reveal line distortion caused by the mechanical strain imparted by the thermal contractions of the metal relative to the underlying crystal. Coherent oscillations are also observed for the most highly strained ions
Measurement of the double-differential inclusive jet cross section in proton-proton collisions at = 5.02 TeV
No full textInternational audienceThe inclusive jet cross section is measured as a function of jet transverse momentum and rapidity . The measurement is performed using proton-proton collision data at = 5.02 TeV, recorded by the CMS experiment at the LHC, corresponding to an integrated luminosity of 27.4 pb. The jets are reconstructed with the anti- algorithm using a distance parameter of = 0.4, within the rapidity interval 2, and across the kinematic range 0.06 1 TeV. The jet cross section is unfolded from detector to particle level using the determined jet response and resolution. The results are compared to predictions of perturbative quantum chromodynamics, calculated at both next-to-leading order and next-to-next-to-leading order. The predictions are corrected for nonperturbative effects, and presented for a variety of parton distribution functions and choices of the renormalization/factorization scales and the strong coupling
Opto-RF transduction in Er3+:CaWO4
No full textInternational audienceWe use an erbium doped CaWO crystal as a resonant transducer between the RF and optical domains at 12 GHz and 1532 nm respectively. We employ a RF resonator to enhance the spin coupling but keep a single-pass (non-resonant) setup in optics. The overall efficiency is low but we carefully characterize the transduction process and show that the performance can be described by two different metrics that we define and distinguish: the electro-optics and the quantum efficiencies. We reach an electro-optics efficiency of -84 dB for 15.7 dBm RF power. The corresponding quantum efficiency is -142 dB for 0.4 dBm optical power. We develop the Schrödinger-Maxwell formalism, well-known to describe light-matter interactions in atomic systems, in order to model the conversion process. We explicitly make the connection with the cavity quantum electrodynamics (cavity QED) approach that are generally used to describe quantum transduction
Constraints on lepton number violation with the 2 tonne · year CUORE dataset
No full textInternational audienceThe matter-antimatter asymmetry underlines the incompleteness of the current understanding of particle physics. Neutrinoless double-beta () decay may help explain this asymmetry, while unveiling the Majorana nature of the neutrino. The CUORE experiment searches for decay of Te using a tonne-scale cryogenic calorimeter operated at milli-kelvin temperatures. We report no evidence for decay and place a lower limit on the half-life of T> 3.8 10 years (90% C.I.) with over 2 tonneyear TeO exposure. The tools and techniques developed for this result and the 5 year stable operation of nearly 1000 detectors demonstrate the infrastructure for a next-generation experiment capable of searching for decay across multiple isotopes
Broadband parametric amplification for multiplexed SiMOS quantum dot signals
No full textInternational audienceSpins in semiconductor quantum dots hold great promise as building blocks of quantum processors. Trapping them in SiMOS transistor-like devices eases future industrial scale fabrication. Among the potentially scalable readout solutions, gate-based dispersive radiofrequency reflectometry only requires the already existing transistor gates to readout a quantum dot state, relieving the need for additional elements. In this effort towards scalability, traveling-wave superconducting parametric amplifiers significantly enhance the readout signal-to-noise ratio (SNR) by reducing the noise below typical cryogenic low-noise amplifiers, while offering a broad amplification band, essential to multiplex the readout of multiple resonators. In this work, we demonstrate a 3GHz gate-based reflectometry readout of electron charge states trapped in quantum dots formed in SiMOS multi-gate devices, with SNR enhanced thanks to a Josephson traveling-wave parametric amplifier (JTWPA). The broad, tunable 2GHz amplification bandwidth combined with more than 10dB ON/OFF SNR improvement of the JTWPA enables frequency and time division multiplexed readout of interdot transitions, and noise performance near the quantum limit. In addition, owing to a design without superconducting loops and with a metallic ground plane, the JTWPA is flux insensitive and shows stable performances up to a magnetic field of 1.2T at the quantum dot device, compatible with standard SiMOS spin qubit experiments
Pure Gravitational Wave Estimation of Hubble's Constant using Neutron Star-Black Hole Mergers
No full textInternational audienceHere we show how can be derived purely from the gravitational waves (GW) of neutron star-black hole (NSBH) mergers. This new method provides an estimate of spanning the redshift range, with current GW sensitivity and without the need for any afterglow detection. We utilise the inherently tight neutron star mass function together with the NSBH waveform amplitude and frequency to estimate distance and redshift respectively, thereby obtaining statistically. Our first estimate is km s Mpc for the secure NSBH events GW190426 and GW200115. We forecast that soon, with 10 more such NSBH events we can reach competitive precision of
Finite Integrals from Feynman Polytopes
No full textInternational audienceWe investigate a geometric approach to determining the complete set of numerators giving rise to finite Feynman integrals. Our approach proceeds graph by graph, and makes use of the Newton polytope associated to the integral's Symanzik polynomials. It relies on a theorem by Berkesch, Forsgård, and Passare on the convergence of Euler--Mellin integrals, which include Feynman integrals. We conjecture that a necessary in addition to a sufficient condition is that all parameter-space monomials lie in the interior of the polytope. We present an algorithm for finding all finite numerators based on this conjecture. In a variety of examples, we find agreement between the results obtained using the geometric approach, and a Landau-analysis approach developed by Gambuti, Tancredi, and two of the authors
gSeaGen code by KM3NeT: an efficient tool to propagate muons simulated with CORSIKA
No full textInternational audienceThe KM3NeT Collaboration has tackled a common challenge faced by the astroparticle physics community, namely adapting the experiment-specific simulation software to work with the CORSIKA air shower simulation output. The proposed solution is an extension of the open-source code gSeaGen, allowing for the transport of muons generated by CORSIKA to a detector of any size at an arbitrary depth. The gSeaGen code was not only extended in terms of functionalities but also underwent a thorough redesign of the muon propagation routine, resulting in a more accurate and efficient simulation. This paper presents the capabilities of the new gSeaGen code as well as prospects for further developments
An end-to-end calibration of the Mini-EUSO detector in space
No full textInternational audienceMini-EUSO is a wide Field-of-View (44∘×44∘) telescope currently in operation from a nadir-facing Ultra-Violet (UV) transparent window in the Russian Zvezda module on the International Space Station (ISS). Mini-EUSO has been designed as a scaled-down version of the original JEM-EUSO telescope to raise its instrumentation’s technological readiness level and demonstrate its observational principle, while performing multidisciplinary studies on different fields such as atmospheric science and planetology. One of Mini-EUSO main goals is the study of the UV background for future space missions employing the same concept as the original JEM-EUSO telescope, which requires an absolute calibration of the Mini-EUSO instrument. During the past years, a few observational campaigns have been completed, employing a ground-based UV flasher to perform an end-to-end calibration of the instrument. In this paper, we present the assembled UV flasher system, the operation of the field campaign and the analysis of the obtained data. The results are interpreted by the means of a parametrization of the Mini-EUSO photon counts. The end-to-end efficiency of several pixels has been obtained, taking into account different parameters such as the atmospheric attenuation, the optics efficiency and the multi-anode photomultiplier detection efficiency