On the impact of the Migdal effect in reactor CEν\nuNS experiments

The search for coherent elastic neutrino nucleus scattering (CE$\nu$NS) using reactor antineutrinos represents a formidable experimental challenge, recently boosted by the observation of such a process at the Dresden-II reactor site using a germanium detector. This observation relies on an unexpected enhancement at low energies of the measured quenching factor with respect to the theoretical Lindhard model prediction, which implies an extra observable ionization signal produced after the nuclear recoil. A possible explanation for this additional contribution could be provided by the so-called Migdal effect, which however has never been observed. Here, we study in detail the impact of the Migdal contribution to the standard CE$\nu$NS signal calculated with the Lindhard quenching factor, finding that the former is completely negligible for observed energies below $\sim 0.3\,\mathrm{keV}$ where the signal is detectable, and thus unable to provide any contribution to CE$\nu$NS searches in this energy regime. To this purpose, we compare different formalisms used to describe the Migdal effect that intriguingly show a perfect agreement, making our findings robust.Comment: 5 pages, 2 figure

Attitude toward prescription and clinical monitoring of lithium salts in a sample of Italian psychiatrists: preliminary data

Results of international prescribing patterns show that lithium prescription and biochemical drug monitoring seem to differ from a country to another. In spite of clear-cut supporting scientific evidence lithium monitoring is often disregarded, incorrectly used or underused. In Italy the trend of lithium prescriptions and biochemical monitoring is far from what suggested in guidelines; even if there's an impressive paucity of data about lithium monitoring and related iatrogenic risks in our country. In order to assess the current attitude in Italy toward lithium treatment in bipolar disorder we asked to a number of senior psychiatrists, working within the national territory, to fill a 34 items interview. Items were grouped in 8 domains, ranging from prescription pattern to therapeutic drug monitoring and other safety measures to prevent iatrogenic harm during lithium therapy. A preliminary analysis of the very first data, collected mainly in Tuscany, suggested that overall knowledge about lithium prescription and biochemical monitoring were good and the few critical topics found in this preliminary study may be addressed with an improvement in information about lithium therapy

Maternal-foetal attachment independently predicts the quality of maternal-infant bonding and post-partum psychopathology

Purpose: The aim of this study was to evaluate the association of maternal antenatal attachment and post-partum psychopathology, maternal–infant bonding, while checking for antenatal psychopathology, for lifetime psychiatric diagnosis and for the known risk factors for peripartum depression. Methods: One hundred and six women recruited at the first month of pregnancy (T0) were evaluated with the structured interview for DSM-IV TR (SCID-I) to assess the presence of lifetime psychiatric diagnosis and with the Perinatal Depression Predictor Inventory-Revised (PDPI-R), the Edinburgh Postnatal Depression Scale (EPDS), and the State–Trait Anxiety Inventory (STAI). At the sixth month of pregnancy (T1) and at the first month post-partum (T2), all patients were evaluated with the PDPI-R, the EPDS, the STAI, at T1, with the Maternal Antenatal Attachment Scale (MAAS), and at T2 with the Maternal Postnatal Attachment Scale (MPAS). Results: Multivariate regression analyses showed that maternal–foetal attachment was the variable most significantly associated with postnatal symptoms of depression and anxiety and with quality of maternal-infant attachment. The logistic regression analyses showed that antenatal attachment may predict postnatal depressive and anxiety symptoms (respectively, OR: 0.83–IC [0.74 − 0.95], p =.005, OR: 0.88–IC [0.79 − 0.98], p =.02), and the quality of maternal postnatal attachment (OR: 1.17–IC [1.08 − 1.27], p <.001), also after taking into account the known risk factors for perinatal depression, the sociodemographic variables and lifetime psychiatric diagnosis. Conclusion: The quality of maternal–foetal bonding may independently predict the quality of maternal–infant attachment and post-partum depressive and anxiety symptoms. A comprehensive assessment of maternal risk factors for perinatal psychopathology during pregnancy should include the evaluation of antenatal attachment that could be modifiable by specific interventions promoting the quality of maternal bonding

Search for dark matter annual modulation with DarkSide-50

Dark matter induced event rate in an Earth-based detector is predicted to show an annual modulation as a result of the Earth's orbital motion around the Sun. We searched for this modulation signature using the ionization signal of the DarkSide-50 liquid argon time projection chamber. No significant signature compatible with dark matter is observed in the electron recoil equivalent energy range above $40~{\rm eV_{ee}}$, the lowest threshold ever achieved in such a search.Comment: 8 pages, 4 figure

Study of cosmogenic activation above ground for the DarkSide-20k experiment

The activation of materials due to exposure to cosmic rays may become an important background source for experiments investigating rare event phenomena. DarkSide-20k, currently under construction at the Laboratori Nazionali del Gran Sasso, is a direct detection experiment for galactic dark matter particles, using a two-phase liquid-argon Time Projection Chamber (TPC) filled with 49.7 tonnes (active mass) of Underground Argon (UAr) depleted in 39Ar. Despite the outstanding capability of discriminating / background in argon TPCs, this background must be considered because of induced dead time or accidental coincidences mimicking dark-matter signals and it is relevant for low-threshold electron-counting measurements. Here, the cosmogenic activity of relevant long-lived radioisotopes induced in the experiment has been estimated to set requirements and procedures during preparation of the experiment and to check that it is not dominant over primordial radioactivity; particular attention has been paid to the activation of the 120 t of UAr used in DarkSide-20k. Expected exposures above ground and production rates, either measured or calculated, have been considered in detail. From the simulated counting rates in the detector due to cosmogenic isotopes, it is concluded that activation in copper and stainless steel is not problematic. The activity of 39Ar induced during extraction, purification and transport on surface is evaluated to be 2.8% of the activity measured in UAr by DarkSide-50 experiment, which used the same underground source, and thus considered acceptable. Other isotopes in the UAr such as 37Ar and 3H are shown not to be relevant due to short half-life and assumed purification methods

Sensitivity projections for a dual-phase argon TPC optimized for light dark matter searches through the ionization channel

Dark matter lighter than 10  GeV/c2 encompasses a promising range of candidates. A conceptual design for a new detector, DarkSide-LowMass, is presented, based on the DarkSide-50 detector and progress toward DarkSide-20k, optimized for a low-threshold electron-counting measurement. Sensitivity to light dark matter is explored for various potential energy thresholds and background rates. These studies show that DarkSide-LowMass can achieve sensitivity to light dark matter down to the solar neutrino fog for GeV-scale masses and significant sensitivity down to 10  MeV/c2 considering the Migdal effect or interactions with electrons. Requirements for optimizing the detector’s sensitivity are explored, as are potential sensitivity gains from modeling and mitigating spurious electron backgrounds that may dominate the signal at the lowest energies

Measurement of isotopic separation of argon with the prototype of the cryogenic distillation plant Aria for dark matter searches

The Aria cryogenic distillation plant, located in Sardinia, Italy, is a key component of the DarkSide-20k experimental program for WIMP dark matter searches at the INFN Laboratori Nazionali del Gran Sasso, Italy. Aria is designed to purify the argon, extracted from underground wells in Colorado, USA, and used as the DarkSide-20k target material, to detector-grade quality. In this paper, we report the first measurement of argon isotopic separation by distillation with the 26 m tall Aria prototype. We discuss the measurement of the operating parameters of the column and the observation of the simultaneous separation of the three stable argon isotopes: 36Ar , 38Ar , and 40Ar . We also provide a detailed comparison of the experimental results with commercial process simulation software. This measurement of isotopic separation of argon is a significant achievement for the project, building on the success of the initial demonstration of isotopic separation of nitrogen using the same equipment in 2019