Laboratoire Souterrain à Bas Bruit

We present the MIGA experiment, an underground long baseline atom interferometer to study gravity at large scale. The hybrid atom-laser antenna will use several atom interferometers simultaneously interrogated by the resonant mode of an optical cavity. The instrument will be a demonstrator for gravitational wave detection in a frequency band (100 mHz-1 Hz) not explored by classical ground and space-based observatories, and interesting for potential astrophysical sources. In the initial instrument configuration, standard atom interferometry techniques will be adopted, which will bring to a peak strain sensitivity of [Formula: see text] at 2 Hz. This demonstrator will enable to study the techniques to push further the sensitivity for the future development of gravitational wave detectors based on large scale atom interferometers. The experiment will be realized at the underground facility of the Laboratoire Souterrain à Bas Bruit (LSBB) in Rustrel-France, an exceptional site located away from major anthropogenic disturbances and showing very low background noise. In the following, we present the measurement principle of an in-cavity atom interferometer, derive the method for Gravitational Wave signal extraction from the antenna and determine the expected strain sensitivity. We then detail the functioning of the different systems of the antenna and describe the properties of the installation site.

Abstract Gravitational waves (GWs) were observed for the first time in 2015, one century after Einstein predicted their existence. There is now growing interest to extend the detection bandwidth to low frequency. The scientific potential of multi-frequency GW astronomy is enormous as it would enable to obtain a more complete picture of cosmic events and mechanisms. This is a unique and entirely new opportunity for the future of astronomy, the success of which depends upon the decisions being made on existing and new infrastructures. The prospect of combining observations from the future space-based instrument LISA together with third generation ground based detectors will open the way toward multi-band GW astronomy, but will leave the infrasound (0.1–10 Hz) band uncovered. GW detectors based on matter wave interferometry promise to fill such a sensitivity gap. We propose the European Laboratory for Gravitation and Atom-interferometric Research (ELGAR), an underground infrastructure based on the latest progress in atomic physics, to study space–time and gravitation with the primary goal of detecting GWs in the infrasound band. ELGAR will directly inherit from large research facilities now being built in Europe for the study of large scale atom interferometry and will drive new pan-European synergies from top research centers developing quantum sensors. ELGAR will measure GW radiation in the infrasound band with a peak strain sensitivity of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"> <mml:mn>3.3</mml:mn> <mml:mo>×</mml:mo> <mml:mn>1</mml:mn> <mml:msup> <mml:mrow> <mml:mn>0</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>22</mml:mn> </mml:mrow> </mml:msup> <mml:mo>/</mml:mo> <mml:msqrt> <mml:mrow> <mml:mtext>Hz</mml:mtext> </mml:mrow> </mml:msqrt> </mml:math> at 1.7 Hz. The antenna will have an impact on diverse fundamental and applied research fields beyond GW astronomy, including gravitation, general relativity, and geology.

Low noise underground environments offer conditions allowing assessment of ultimate performance of high sensitivity sensors such as accelerometers, gyrometers, seismometers⋯ Such facilities are for instance ideal for observing the tiny signals of interest for geophysical studies. Laboratoire Souterrain à Bas Bruit (LSBB) in which we have installed our cold atom gravimeter provides such an environment. We report here the best short term sensitivity ever obtained without any ground vibration isolation system with such an instrument: 10−8 m s−2 in 100 s measurement time.

We report results of a $14.1\text{ }\text{ }\mathrm{kg}\text{ }\mathrm{d}$ measurement with 15 superheated droplet detectors of total active mass 0.208 kg, comprising the first stage of a $30\text{ }\text{ }\mathrm{kg}\text{ }\mathrm{d}$ Phase II experiment. In combination with the results of the neutron-spin sensitive XENON10 experiment, these results yield a limit of $|{a}_{p}|&lt;0.32$ for ${M}_{W}=50\text{ }\text{ }\mathrm{GeV}/{c}^{2}$ on the spin-dependent sector of weakly interacting massive particle-nucleus interactions with a 50% reduction in the previously allowed region of the phase space, formerly defined by XENON, KIMS, and PICASSO. In the spin-independent sector, a limit of $2.3\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}\text{ }\text{ }\mathrm{pb}$ at ${M}_{W}=45\text{ }\text{ }\mathrm{GeV}/{c}^{2}$ is obtained.

Phase II of SIMPLE (Superheated Instrument for Massive ParticLe Experiments) searched for astroparticle dark matter using superheated liquid ${\mathrm{C}}_{2}{\mathrm{ClF}}_{5}$ droplet detectors. Each droplet generally requires an energy deposition with linear energy transfer (LET) $\ensuremath{\gtrsim}150\text{ }\text{ }\mathrm{keV}/\ensuremath{\mu}\mathrm{m}$ for a liquid-to-gas phase transition, providing an intrinsic rejection against minimum ionizing particles of order ${10}^{\ensuremath{-}10}$, and reducing the backgrounds to primarily $\ensuremath{\alpha}$ and neutron-induced recoil events. The droplet phase transition generates a millimetric-sized gas bubble that is recorded by acoustic means. We describe the SIMPLE detectors, their acoustic instrumentation, and the characterizations, signal analysis and data selection, which yield a particle-induced, ``true nucleation'' event detection efficiency of better than 97% at a 95% C.L. The recoil-$\ensuremath{\alpha}$ event discrimination, determined using detectors first irradiated with neutrons and then doped with alpha emitters, provides a recoil identification of better than 99%; it differs from those of COUPP and PICASSO primarily as a result of their different liquids with lower critical LETs. The science measurements, comprising two shielded arrays of fifteen detectors each and a total exposure of 27.77 kgd, are detailed. Removal of the 1.94 kgd Stage 1 installation period data, which had previously been mistakenly included in the data, reduces the science exposure from 20.18 to 18.24 kgd and provides new contour minima of ${\ensuremath{\sigma}}_{p}=4.3\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}\text{ }\text{ }\mathrm{pb}$ at $35\text{ }\text{ }\mathrm{GeV}/{\mathrm{c}}^{2}$ in the spin-dependent sector of astroparticle dark matter--proton interactions and ${\ensuremath{\sigma}}_{N}=3.6\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}\text{ }\text{ }\mathrm{pb}$ at $35\text{ }\text{ }\mathrm{GeV}/{\mathrm{c}}^{2}$ in the spin-independent sector. These results are examined with respect to the fluorine spin and halo parameters used in the previous data analysis.

We report an improved SIMPLE experiment comprising four superheated droplet detectors with a total exposure of 0.42 kgd. The result yields ∼ factor 10 improvement in the previously-reported results, and—despite the low exposure—is seen to provide restrictions on the allowed phase space of spin-dependent coupling strengths almost equivalent to those from the significantly larger exposure NAIAD-CDMS/ZEPLIN searches.

The macrocrustacean fauna from an alluvial aquifer in the French Pyrénées was investigated using 15 wells scattered over the floodplain. Wells were sampled at three contrasting periods for faunal, phy-sical and chemical variables to investigate relationships between amphipod, isopod distributions and environmental factors. The assemblages, dominated by stygobite amphipod species, showed an overall persistence between the sampling dates. Groundwater quality exhibited between-site variations related to agriculturally-induced pollution. Low correlations existed between water quality and fauna distribution patterns. At the scale of the aquifer, groundwater contamination did not influence the macrocrustacean distribution. The spatial distribution of amphipods and isopods was clearly related to hydrogeology and hydrodynamics: strong relationships were found between the assemblages composition and the hydrological context of the stations (wells from the alluvial plain and from the alluvial terrace). With respect to spatial and temporal scales and providing adequate sampling methods, macrocrustaceans then constitute natural indicators of groundwater hydrodynamics in the Ariège aquifer.

Gravitational Waves (GWs) were observed for the first time in 2015, one century after Einstein predicted their existence. There is now growing interest to extend the detection bandwidth to low frequency. The scientific potential of multi-frequency GW astronomy is enormous as it would enable to obtain a more complete picture of cosmic events and mechanisms. This is a unique and entirely new opportunity for the future of astronomy, the success of which depends upon the decisions being made on existing and new infrastructures. The prospect of combining observations from the future space-based instrument LISA together with third generation ground based detectors will open the way towards multi-band GW astronomy, but will leave the infrasound (0.1 Hz to 10 Hz) band uncovered. GW detectors based on matter wave interferometry promise to fill such a sensitivity gap. We propose the European Laboratory for Gravitation and Atom-interferometric Research (ELGAR), an underground infrastructure based on the latest progress in atomic physics, to study space-time and gravitation with the primary goal of detecting GWs in the infrasound band. ELGAR will directly inherit from large research facilities now being built in Europe for the study of large scale atom interferometry and will drive new pan-European synergies from top research centers developing quantum sensors. ELGAR will measure GW radiation in the infrasound band with a peak strain sensitivity of $4.1 \\times 10^{-22}/\\sqrt{\\text{Hz}}$ at 1.7 Hz. The antenna will have an impact on diverse fundamental and applied research fields beyond GW astronomy, including gravitation, general relativity, and geology.

The anatomy and development of the eye of Proteus anguinus are described. The relationships between organogenesis of the eye in embryos and larva and its involution in the young and the adult are discussed. The availability (in breeding cultures) of a significant number of Proteus embryos (which are normally rare) allowed experimental analysis of the effects of light, xenoplastic differentiation and thyroid hormones on the development of the eye. The results of this study suggest that development and involution of the eye of Proteus are controlled by genetic factors which are not greatly influenced by environment, and one can, therefore, consider the microphthalmy of Proteus as a relict characteristic which is the result of a specific development with disturbance of the normal ontogenic process.

SIMPLE 2000 ({\\underline S}uperheated {\\underline I}nstrument for {\\underline M}assive {\\underline P}artic{\\underline {LE}} searches) will consist of an array of eight to sixteen large active mass ($\\sim15$ g) Superheated Droplet Detectors(SDDs) to be installed in the new underground laboratory of Rustrel-Pays d'Apt. Several factors make of SDDs an attractive approach for the detection of Weakly Interacting Massive Particles (WIMPs), namely their intrinsic insensitivity to minimum ionizing particles, high fluorine content, low cost and operation near ambient pressure and temperature. We comment here on the fabrication, calibration and already-competitive first limits from SIMPLE prototype SDDs, as well as on the expected immediate increase in sensitivity of the program, which aims at an exposure of $&gt;$25 kg-day during the year 2000. The ability of modest-mass fluorine-rich detectors to explore regions of neutralino parameter space beyond the reach of the most ambitious cryogenic projects is pointed out.

This document presents a summary of the 2023 Terrestrial Very-Long-Baseline Atom Interferometry Workshop hosted by CERN. The workshop brought together experts from around the world to discuss the exciting developments in large-scale atom interferometer (AI) prototypes and their potential for detecting ultralight dark matter and gravitational waves. The primary objective of the workshop was to lay the groundwork for an international TVLBAI proto-collaboration. This collaboration aims to unite researchers from different institutions to strategize and secure funding for terrestrial large-scale AI projects. The ultimate goal is to create a roadmap detailing the design and technology choices for one or more kilometer--scale detectors, which will be operational in the mid-2030s. The key sections of this report present the physics case and technical challenges, together with a comprehensive overview of the discussions at the workshop together with the main conclusions.

Fluctuations of the Earth's gravitational field are a major noise source for ground-based experiments investigating general-relativistic phenomena such as gravitational waves (GWs). Mass density variations caused by local seismic or atmospheric perturbations determine spurious differential displacements of the free-falling test masses---called gravity gradient noise (GGN)---which mimics GW effects. This GGN is expected to become dominant in the infrasound domain and must be tackled for the future realization of observatories exploring GWs at low frequency. GGN will be studied with the MIGA experiment, a demonstrator for low-frequency GW detection based on atom interferometry currently being constructed at the low-noise underground Laboratoire Souterrain \`a Bas Bruit (LSBB) in France. MIGA will provide precise measurements of local gravity, probed by a network of three free-falling atom test masses separated by up to 150 m. We model the effect of GGN for MIGA and use seismic and atmospheric data recorded at LSBB to characterize their impact on future measurements. We show that the antenna will be able to characterize GGN using dedicated data analysis methods.

BACKGROUND: Although the burden of opioid use disorder is disproportionately high among persons who are incarcerated, medications for opioid use disorder are often unavailable in correctional settings. The Rhode Island Department of Corrections provides all 3 classes of medications for opioid use disorder to clinically eligible persons who are incarcerated. Despite a decrease in fatal overdoses among persons with recent criminal legal system involvement since the program's implementation, barriers to continued engagement in treatment after release from incarceration still exist. METHODS: We conducted 40 semistructured, qualitative interviews with people who were incarcerated and enrolled in the comprehensive medications for opioid use disorder program at the Rhode Island Department of Corrections. Analysis applied a general, inductive approach using NVivo 12. RESULTS: Participants discussed barriers to treatment engagement before incarceration, as well as anticipated barriers to medications to treat opioid use disorder continuation after release from incarceration. Structural factors including housing, health insurance, transportation, and the treatment program structure, as well as social factors such as social support networks were perceived to influence retention in medications to treat opioid use disorder post-release. CONCLUSION: Our findings suggest that people with opioid use disorder who are incarcerated encounter unique challenges upon community reentry. Addressing structural factors that pose barriers to post-release engagement is essential to sustaining retention. We recommend utilization of peer recovery specialists to alleviate some of the stress of navigating the structural barriers identified by participants.

The permanent operation of a 3 axes SQUID magnetometer in the LSBB below 550 m of calcite rock is a unique system of magnetic observation: a rejection rate better than 3 fT/Hz over 40 Hz. The observation of magneto-ionosphere responses to P wave emissions both at the epicentre and at their arrival at LSBB for earthquakes of magnitude larger than 3 is reported. A simple model predicts the starting time of these events. These results are compared with those provided by Doppler sounders for ionosphere responses to Rayleigh waves.

We propose a marginally stable optical resonator suitable for atom interferometry. The resonator geometry is based on two flat mirrors at the focal planes of a lens that produces the large beam waist required to coherently manipulate cold atomic ensembles. Optical gains of about 100 are achievable&#13;\nusing optics with part-per-thousand losses. The resulting power build-up will allow for enhanced coherent manipulation of the atomic wavepackets such as large separation beamsplitters. We study the effect of longitudinal misalignments and assess the robustness of the resonator in terms of&#13;\nintensity and phase profiles of the intra-cavity field. We also study how to implement atom interferometry based on large momentum transfer Bragg diffraction in such a cavity.

Conditioning experiments revealed that Proteus perceives a back-and-forth moving (approximately 1 Hz) direct-current field and its polarity. Minimum behavioral thresholds occurred at a current density of 0.15 microA/cm2, corresponding to a voltage gradient of 0.5 mV/cm. Recordings from afferent nerve fibers showed that ampullary electroreceptors in Proteus respond as do other nonteleost receptors, i.e. with an increase in discharge rate to cathodal current and a decrease to anodal current (threshold: approximately 1 mV/cm).

This study investigated the efficacy and safety of masitinib, a selective tyrosine kinase inhibitor capable of downregulating mast cell functions, for treatment of canine atopic dermatitis (CAD). Dogs with confirmed CAD received masitinib at 12.5 mg/kg/day (n = 202) or control (n = 104) for 12 weeks. A reduction in CAD Extent and Severity Index (CADESI-02) score of ≥ 50% at week 12 was observed in 61% of masitinib-treated dogs versus 35% of control dogs (P < 0.001), according to the modified intent-to-treat population. For dogs resistant to ciclosporin and/or corticosteroids (60% of the study population), CADESI-02 response rates were 60 versus 31%, respectively (P = 0.004). The mean reduction in pruritus score of severely pruritic dogs was 46 versus 29%, respectively (P = 0.045). Furthermore, 65% of owners with severely pruritic dogs assessed masitinib efficacy as good/excellent versus 35% control (P = 0.05). Overall, 63% of investigators assessed masitinib efficacy as good/excellent versus 35% control (P < 0.001). Premature discontinuations from the modified intent-to-treat population (28.2% masitinib versus 26.0% control) were mainly due to adverse events (13.4 versus 4.8%, respectively) or lack of efficacy (12.4 versus 18.3%, respectively). In total, 13.2% dogs presented with severe adverse events (16.0% masitinib versus 7.7% control). Masitinib showed a risk of reversible protein loss, although regular surveillance of blood albumin and proteinuria allowed for discontinuation of treatment while the dog was still clinically asymptomatic. Masitinib proved to be an effective and mostly well-tolerated treatment of CAD, including severe and refractory cases, with medically manageable adverse effects.

The MIGA project aims at demonstrating precision measurements of gravity with cold atom sensors in a large scale instrument and at studying the associated applications in geosciences and fundamental physics. The first stage of the project (2013-2018) will consist in building a 300-meter long optical cavity to interrogate atom interferometers and will be based at the low noise underground laboratory LSBB in Rustrel, France. The second stage of the project (2018-2023) will be dedicated to science runs and data analyses in order to probe the spatio-temporal structure of the local gravity field of the LSBB region, a site of high hydrological interest. MIGA will also assess future potential applications of atom interferometry to gravitational wave detection in the frequency band $\sim 0.1-10$ Hz hardly covered by future long baseline optical interferometers. This paper presents the main objectives of the project, the status of the construction of the instrument and the motivation for the applications of MIGA in geosciences. Important results on new atom interferometry techniques developed at SYRTE in the context of MIGA and paving the way to precision gravity measurements are also reported.

This pilot study investigates effects of an ultra shielded capsule at the low-noise underground laboratory (LSBB), Rustrel, France, when used to acquire scalp electroencephalogram (EEG). Analysis of EEG recordings from three volunteers confirms that clean EEG signals can be acquired in the LSBB capsule without the need for notch filtering. In addition, using different setups for acquiring EEG in the capsule, statistical analysis of power spectral densities based on a geodesic distance measure reveals that the laptop computer and patient module do not introduce any noise on recorded signals. Moreover, the current study shows that the backward counting task as a mental activity can be better detected using the EEG acquired in the capsule due to the higher level of â-band activities. The counting-relaxed â-band energy ratio is calculated using the S transform and compared between the hospital and capsule, revealing significantly higher values in the capsule (p < 0.05). Exploring the relative â-band energy (ratio of â-band energy to that of 0-12 Hz in counting state) reveals that the average of this measure is higher in the capsule for all subjects. Those results demonstrate the potential of the LSBB capsule for novel EEG studies, including establishing novel low-noise EEG benchmarks.

Measurements performed with the High Energy Range Multisphere Extended IRSN System (HERMEIS) acquired by the French Aerospace Lab are presented and discussed. The detectors were calibrated at the Low Noise Underground Laboratory of Rustrel. Atmospheric neutron spectra were obtained at three altitudes ( <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">${+}500$</tex></formula> m, <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">${+}1000$</tex></formula> m and <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">${+}2885$</tex></formula> m) and the first results about the continuous measurements of the Natural Radiative Environment at the Pic du Midi are presented with a discussion about the uncertainties.