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SuperSUN, a new superthermal source of ultracold neutrons (UCN) at the Institut Laue-Langevin, exploits inelastic scattering of neutrons in isotopically pure superfluid $^4$He at temperatures below $0.6\,$K. For the first time, continuous operation with an intense broad-spectrum cold neutron beam is demonstrated over 60 days. We observe continuous UCN extraction rates of $21000\,$s$^{-1}$, and storage in the source with saturated $\textit{in-situ}$ density $273\,$cm$^{-3}$. The high stored density, low-energy UCN spectrum, and long storage times open new possibilities in fundamental and applied physics.

The extreme variability of blazars, in both timescale and amplitude, is generally explained as the effect of a relativistic jet closely aligned to the observer's line-of-sight. Due to causality arguments, variability characteristics translate into spatial information about the emitting region of blazars. Since radiation at different wavelengths is emitted in different parts of the jet, multi-frequency observations provide us with a virtual view of the structure of the jet on different scales. Radio--gamma-ray correlations, moreover, are essential to reveal where and how the high-energy radiation is produced. We present here the observations collected within the blazar radio monitoring program that we are running at the Medicina and Noto telescopes. It aims at investigating how the variability characteristics and spectral energy distribution of blazars evolve in time. Since 2004, observation have been performed at 5, 8, 24, and 43 GHz on 47 targets, with monthly cadence; the monitoring program is still active at frequencies of 8 and 24 GHz. The database we built in more than twenty years of activity comprises to date about 21000 flux density measurements. Some basic analysis tools h

Production of the High Granularity Timing Detector for the ATLAS experiment at High Luminosity LHC requires over 21000 silicon sensors based on Low Gain Avalanche Diode (LGAD) technology. Their radiation hardness is monitored as a part of the production quality control. Dedicated test structures from each wafer are irradiated with neutrons and a fast and comprehensive characterization is required. We introduce a new test method based on Transient Current Technique (TCT) performed in the interface region of two LGAD devices. The measurement enables extraction of numerous sensor performance parameters, such as LGAD gain layer depletion voltage, LGAD gain dependence on bias voltage, sensor leakage current and effective interpad distance. Complementary capacitance-voltage measurements and charge collection measurements with 90Sr on the same samples have been performed to calibrate the TCT results in terms of charge collection and define acceptance criteria for wafer radiation hardness in the ATLAS-HGTD project.

AGB stars are the primary source of dust and complex molecules in the interstellar medium. The determination of outflow parameters is often hindered by the unknown geometry of the circumstellar environment, creating a demand for high-angular resolution observations. We use our NIR spectra and photometry of the carbon AGB star V Cyg, along with literature data, to construct its SED over a wide range of wavelengths. The dust envelope responsible for the IR excess was also resolved in scattered polarized light at angular scales of 50-80 mas using differential speckle polarimetry. We present an interpretation of the thermal and scattered radiation of the dust using models of a spherical dusty outflow (Mdust = 5.3e-7 M_sun) and an inclined equatorial density enhancement, either in the form of a disk (Mdust = 7.6e-3 M_earth) or a torus (Mdust = 5.7e-3 M_earth), which material is concentrated at stellocentric distances less than 25 AU. The dust material consists of amorphous carbon and SiC, with 84% of the dust being amorphous carbon. Dust particle radii range from 5 to 950 nm and follow a power law with an exponent of -3.5. Modeling of the envelope allowed us to improve the accuracy of s

To date, several methods have been developed to explain deep learning algorithms for classification tasks. Recently, an adaptation of two of such methods has been proposed to generate instance-level explainable maps in a semantic segmentation scenario, such as multiple sclerosis (MS) lesion segmentation. In the mentioned work, a 3D U-Net was trained and tested for MS lesion segmentation, yielding an F1 score of 0.7006, and a positive predictive value (PPV) of 0.6265. The distribution of values in explainable maps exposed some differences between maps of true and false positive (TP/FP) examples. Inspired by those results, we explore in this paper the use of characteristics of lesion-specific saliency maps to refine segmentation and detection scores. We generate around 21000 maps from as many TP/FP lesions in a batch of 72 patients (training set) and 4868 from the 37 patients in the test set. 93 radiomic features extracted from the first set of maps were used to train a logistic regression model and classify TP versus FP. On the test set, F1 score and PPV were improved by a large margin when compared to the initial model, reaching 0.7450 and 0.7817, with 95% confidence intervals of [

Link function is a key tool in the binomial regression model defined as non-linear model under GLM approach. It transforms the nonlinear regression to linear model with converting the interval (-\infty,\infty) to the probability [0,1]. The binomial model with link functions (logit, probit, cloglog and cauchy) are applied on the proportional of child malnutrition age 0-5 years in each household level. Multiple Indicator Cluster survey (MICS)-2019, Bangladesh was conducted by a joint cooperation of UNICEF and BBS . The survey covered 64000 households using two stage stratified sampling technique, where around 21000 household have children age 0-5 years. We use bi-variate analysis to find the statistical association between response and sociodemographic features. In the binary regression model, probit model provides the best result based on the lowest standard error of covariates and goodness of fit test (deviance, AIC).

Although child malnutrition is improving over the world in the last couple of decades, still now it is concerning issue among the developing countries including Bangladesh. In general, malnutrition is a dichotomous response variable fitted with logistic regression model. But in this study, counting number of malnourished children in each household is defined as response variable. UNICEF with co-operating Bangladesh Bureau of Statistics (BBS) conducted Multiple Indicator Cluster Survey (MICS) covering 64000 households in Bangladesh by using two stage stratified sampling technique, where 21000 households have children age 0-5 years. We use bivariate analysis figuring out significant association between target and socio-demographic predictor variables. Then Negative binomial regression model is used over poisson regression model due to arising over-dispersion problem ($variance > mean$). Zero inflated negative binomial model also is applied for the excess of zeros in the target variable. Considering standard error and significant level of individual factors NB model provides better result as compare to ZINB.

This study presents an experimental dataset documenting the evolution of a turbulent boundary layer downstream of a rough-to-smooth surface transition. To investigate the effect of upstream flow conditions, two groups of experiments are conducted. For the \emph{Group-Re} cases, a nominally constant viscous-scaled equivalent sand grain roughness $k_{s0}^+\approx160$ is maintained on the rough surface, while the friction Reynolds number $Re_{τ0}$ ranges from 7100 to 21000. For the \emph{Group-ks} cases, $Re_{τ0}\approx14000$ is maintained while $k_{s0}^+$ ranges from 111 to 228. The wall-shear stress on the downstream smooth surface is measured directly using oil-film interferometry to redress previously reported uncertainties in the skin-friction coefficient recovery trends. In the early development following the roughness transition, the flow in the internal layer is not in equilibrium with the wall-shear stress. This conflicts with the common practise of modelling the mean velocity profile as two log laws below and above the internal layer height, as first proposed by Elliott (\textit{Trans. Am. Geophys. Union}, vol. 39, 1958, pp 1048--1054). As a solution to this, the current dat

We present Herschel-PACS spectroscopy of four main-sequence star-forming galaxies at z~1.5. We detect [OI]63micron line emission in BzK-21000 at z=1.5213, and measure a line luminosity, L([OI]63micron) = (3.9+/-0.7)x1.E+9 Lsun. Our PDR modelling of the interstellar medium in BzK-21000 suggests a UV radiation field strength, G~320 G0, and gas density, n~1800 cm-3, consistent with previous LVG modelling of the molecular CO line excitation. The other three targets in our sample are individually undetected in these data, and we perform a spectral stacking analysis which yields a detection of their average emission and an [OI]63micron line luminosity, L([OI]63micron) =(1.1+/-0.2)x1E+9 Lsun. We find that the implied luminosity ratio, L([OI]63micron)/L(IR), of the undetected BzK-selected star-forming galaxies broadly agrees with that of low-redshift star-forming galaxies, while BzK-21000 has a similar ratio to that of a dusty star-forming galaxy at z~6. The high [OI]63micron line luminosities observed in BzK-21000 and the $z \sim 1 -3$ dusty and submm luminous star-forming galaxies may be associated with extended reservoirs of low density, cool neutral gas.

Intrusion detection systems perform post-compromise detection of security breaches whenever preventive measures such as firewalls do not avert an attack. However, these systems raise a vast number of alerts that must be analysed and triaged by security analysts. This process is largely manual, tedious and time-consuming. Alert correlation is a technique that tries to reduce the number of intrusion alerts by aggregating those that are related in some way. However, the correlation is performed outside the IDS through third-party systems and tools, after the high volume of alerts has already been raised. These other third-party systems add to the complexity of security operations. In this paper, we build on the very researched area of correlation techniques by developing a novel hierarchical event correlation model that promises to reduce the number of alerts issued by an Intrusion Detection System. This is achieved by correlating the events before the IDS classifies them. The proposed model takes the best of features from similarity and graph-based correlation techniques to deliver an ensemble capability not possible by either approach separately. Further, we propose a correlation pr

One of the novelties of the Gaia-DR3 with respect to the previous data releases is the publication of the multiband light curves of about 1 million AGN. The goal of this work was the creation of a catalogue of variable AGN, whose selection was based on Gaia data only. We first present the implementation of the methods to estimate the variability parameters into a specific object study module for AGN. Then we describe the selection procedure that led to the definition of the high-purity variable AGN sample and analyse the properties of the selected sources. We started from a sample of millions of sources, which were identified as AGN candidates by 11 different classifiers based on variability processing. Because the focus was on the variability properties, we first defined some pre-requisites in terms of number of data points and mandatory variability parameters. Then a series of filters was applied using only Gaia data and the Gaia Celestial Reference Frame 3 (Gaia-CRF3) sample as a reference.The resulting Gaia AGN variable sample, named GLEAN, contains about 872000 objects, more than 21000 of which are new identifications. We checked the presence of contaminants by cross-matching

We report the detection of the CO J=1-0 emission line in three near-infrared selected star-forming galaxies at z~1.5 with the Very Large Array (VLA) and the Green Bank telescope (GBT). These observations directly trace the bulk of molecular gas in these galaxies. We find H_2 gas masses of 8.3 \pm 1.9 x 10^{10} M_sun, 5.6 \pm 1.4 x 10^{10} M_sun and 1.23 \pm 0.34 x 10^{11} M_sun for BzK-4171, BzK-21000 and BzK-16000, respectively, assuming a conversion alpha_CO=3.6 M_sun (K km s^{-1} pc^{2})^{-1}. We combined our observations with previous CO 2-1 detections of these galaxies to study the properties of their molecular gas. We find brightness temperature ratios between the CO 2-1 and CO 1-0 emission lines of 0.80_{-0.22}^{+0.35}, 1.22_{-0.36}^{+0.61} and 0.41_{-0.13}^{+0.23} for BzK-4171, BzK-21000 and BzK-16000, respectively. At the depth of our observations it is not possible to discern between thermodynamic equilibrium or sub-thermal excitation of the molecular gas at J=2. However, the low temperature ratio found for BzK-16000 suggests sub-thermal excitation of CO already at J=2. For BzK-21000, a Large Velocity Gradient model of its CO emission confirms previous results of the low-

The Extremely Large Telescopes will require hundreds of actuators across the pupil for high Strehl in the visible. We envision a triple-stage AO (TSAO) system for GMT/GMagAO-X to achieve this. The first stage is a 4K DM controlled by an IR pyramid wavefront sensor that provides the first order correction. The second stage contains the high-order parallel DM of GMagAO-X that has 21000 actuators and contains an interferometric delay line for phasing of each mirror segment. This stage uses a Zernike wavefront sensor for high-order modes and a Holographic Dispersed Fringe Sensor for segment piston control. Finally, the third stage uses a dedicated 3K dm for non-common path aberration control and the coronagraphic wavefront control by using focal plane wavefront sensing and control. The triple stage architecture has been chosen to create simpler decoupled control loops. This work describes the performance of the proposed triple-stage AO architecture for ExAO with GMagAO-X.

We explore the gas-to-dust mass ratio (G/D) and the CO luminosity-to-Mgas conversion factor (a_co) of two well studied galaxies in the GOODS-N field, that are expected to have different star forming modes, the starburst GN20 at z=4.05 and the normal star-forming galaxy BzK-21000 at z=1.52. Detailed sampling is available for their Rayleigh-Jeans emission via ground based mm interferometry (1.1-6.6mm) along with Herschel, PACS and SPIRE data that probe the peak of their infrared emission. Using the physically motivated Draine & Li (2007) models, as well as a modified black body function, we measure the dust mass (Md) of the sources and find 2.0^{+0.7}_{-0.6} x 10^{9} Msun for GN20 and 8.6^{+0.6}_{-0.9} x 10^{8} Msun for BzK-21000. The addition of mm data reduces the uncertainties of the derived Md by a factor of ~2, allowing the use of the local G\D vs metallicity relation to place constraints on the a_co values of the two sources. For GN20 we derive a conversion factor of a_co < 1.0 Msun pc^{-2}(K km s^{-1})^{-1}, consistent with that of local ULIRGs, while for BzK-21000 we find a considerably higher value, a_co ~4.0 Msun pc^{-2}(K km s^{-1})^{-1}, in agreement with an indepe

We present the results of the longest yet undertaken search for apparently extragalactic radio bursts at the Bleien Radio Observatory covering 21000 hours (898 days). The data were searched for events of less than 50 ms FWHM duration showing a $ν^{-2}$ drift in the spectrogram characteristic of the delay of radio waves in plasma. We have found five cases suggesting dispersion measures between 350 and 400 cm$^{-3}$ pc while searching in the range of 50 -- 2000 cm$^{-3}$ pc. Four of the five events occurred between 10.27 and 11.24 a.m. local civil time. The only exception occurred at night with the full moon in the beam. It was an event that poorly fits plasma dispersion, but had the characteristics of a solar type III burst. However, we were not able to confirm that it was a lunar reflection. All events were observed with a log-periodic dipole within 6800 hours but none with a more directional horn antenna observing the rest of the time. These properties suggest a terrestrial origin of the "peryton" type reported before. However, the cause of these events remains ambiguous.

The $ε$ mechanism is a self-excitation mechanism of stellar pulsations which acts in regions inside the star where nuclear burning takes place. It has been shown that the $ε$ mechanism can excite pulsations in models of hot pre-horizontal branch stars, and that the shortest periods of LS IV-14$^{\circ}$116 could be explained that way. We aim to study the $ε$ mechanism in stellar models appropriate for hot pre-horizontal branch stars to predict their pulsational properties and the instability domain in the $\log g-\log T_{\rm eff}$ plane. We perform detailed computations of non-adiabatic non-radial pulsations on stellar models during the helium subflashes just before the helium-core burning phase. We find an instability domain of long-period gravity modes due to the $ε$ mechanism in the $\log g-\log T_{\rm eff}$ plane at roughly $22000\,{\rm K} \lesssim T_{\rm eff}\lesssim 50000\,$K and $4.67 \lesssim \log g \lesssim 6.15$. Consequently, we find instabilities due to the $ε$ mechanism on pre-extreme horizontal branch stellar models ($T_{\rm eff}\gtrsim 22000\,$K), but not on pre-blue horizontal branch stellar models ($T_{\rm eff}\lesssim 21000\,$K). The periods of excited modes range

We present the UV photometry of the old open cluster NGC188 obtained using images acquired with Ultraviolet Imaging Telescope (UVIT) on board the ASTROSAT satellite, in two far-UV (FUV) and one near-UV (NUV) filters. UVIT data is utilised in combination with optical photometric data to construct the optical and UV colour-magnitude diagrams (CMDs). In the FUV images, we detect only hot and bright blue straggler stars (BSSs), one hot subdwarf, and one white dwarf (WD) candidate. In the NUV images, we detect members up to a faintness limit of ~22 mag including 21 BSSs, 2 yellow straggler stars (YSSs), and one WD candidate. This study presents the first NUV-optical CMDs, and are overlaid with updated BaSTI-IAC isochrones and WD cooling sequence, which are found to fit well to the observed CMDs. We use spectral energy distribution (SED) fitting to estimate the effective temperatures, radii, and luminosities of the UV-bright stars. We find the cluster to have an HB population with three stars (Teff = 4750 - 21000 K). We also detect two yellow straggler stars, with one of them with UV excess connected to its binarity and X-ray emission.

We present preliminary photometric results of a monitoring study of the open cluster NGC 2660 as part of the EXPLORE/OC project to find planetary transits in Galactic open clusters. Analyzing a total of 21000 stars (3000 stars with photometry to 1% or better) yielded three light curves with low-amplitude signals like those typically expected for transiting hot Jupiters. Although their eclipses are most likely caused by non-planetary companions, our methods and photometric precision illustrate the potential to detect planetary transits around stars in nearby open clusters.

We present observations of the most radio-luminous BAL quasar known, 1624+3758, at redshift z = 3.377. The quasar has several unusual properties: (1) The FeII UV191 1787-A emission line is very prominent. (2) The BAL trough (BALnicity index 2990 km/s) is detached by 21000 km/s and extends to velocity v = -29000 km/s. There are additional intrinsic absorbers at -1900 and -2800 km/s. (3) The radio rotation measure of the quasar, 18350 rad/m^2, is the second-highest known. The radio luminosity is P(1.4GHz) = 4.3 x 10^27 W/Hz (H0 = 50 km/s/Mpc, q0 = 0.5), radio loudness R* = 260. The radio source is compact (<~ 2.8 kpc) and the radio spectrum is GHz-peaked, consistent with it being relatively young. The width of the CIV emission line, in conjunction with the total optical luminosity, implies black-hole mass ~ 10^9 M(sun), L/L(Eddington) ~ 2. The high Eddington ratio, and the radio-loudness, place this quasar in one corner of Boroson's (2002) 2-component scheme for the classification of AGN, implying a very high accretion rate, and this may account for some of the unusual observed properties. A complex mini-BAL absorber at v = -3000 km/s is detected in each of CIV, NV and OVI. The bl