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Measuring the escape fraction, $f_{\rm esc}$, of ionizing, Lyman Continuum (LyC) radiation is key to our understanding of the process of cosmic reionization. In this paper we provide a methodology for recovering the posterior probability distribution of the LyC escape fraction, $f_{\rm esc}^{\rm PDF}$, considering both the observational uncertainties and ensembles of simulated transmission functions through the intergalactic medium (IGM). We present an example of this method applied to a VUDS galaxy at $z=3.64$ and find $f_{\rm esc}^{\rm PDF}$ = 0.51$^{+0.33}_{-0.34}$ and compare this to the values computed assuming averaged IGM transmission with and without consideration of detection bias along average sightlines yielding $f_{\rm esc}^{\langle T \rangle}$ = 1.40$^{+0.80}_{-0.42}$, and $f_{\rm esc}^{\rm bias}$ = 0.82$^{+0.33}_{-0.16}$. Our results highlight the limitations of methods assuming average, smooth transmission functions. We also present MOSFIRE data for a sample of seven LyC candidates selected based on photometric redshifts at $z > 3.4$, but find that all seven have overestimated photometric redshifts by $\Delta z \sim 0.2$ making them unsuitable for LyC measurements. This results likely due to a bias induced by our selection criteria., Comment: 12 pages, 9 figues, 2 tables, accepted for publication in MNRAS

This is an Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited., Context. The formation process of fossil groups (FGs) is still under debate, and, because of their relative rarity, large samples of such objects are still missing. Aims. The aim of the present paper is to increase the sample of known FGs, to analyse the properties of their brightest group galaxies (BGGs), and to compare them with a control sample of non-FG BGGs. Methods. We extracted a sample of 87 FG and 100 non-FG candidates from a large spectroscopic catalogue of haloes and galaxies. For all the objects with data available in UNIONS (initially the Canada France Imaging Survey, CFIS) in the u and r bands, and/or in an extra r-band processed to preserve all low-surface-brightness features (rLSB), we performed a 2D photometric fit of the BGG with GALFIT with one or two Sérsic components. We also analysed how the subtraction of the intracluster light (ICL) contribution modifies the BGG properties. From the SDSS spectra available for the BGGs of 65 FGs and 82 non-FGs, we extracted the properties of their stellar populations with Firefly. To complement our study, and in order to provide a detailed illustration of the possible origin of emission lines in the FG BGGs, involving the presence or absence of an AGN, we investigated the origin of the emission lines in a nearby FG that is dominated by the NGC 4104 galaxy. Results. Morphologically, a single Sérsic profile can fit most objects in the u band, while two Sérsics are needed in the r and rLSB bands, both for FGs and non-FGs. Non-FG BGGs cover a larger range of Sérsic index n. FG BGGs follow the Kormendy relation (mean surface brightness versus effective radius) previously derived for almost 1000 brightest cluster galaxies (BCGs), while the majority of non-FGs BGGs are located below this relation, with fainter mean surface brightnesses. This suggests that FG BGGs have evolved similarly to BCGs, and non-FG BGGs have evolved differently from both FG BGGs and BCGs. All the above properties can be strongly modified by the subtraction of the ICL contribution. Based on spectral fitting, the stellar populations of FG and non-FG BGGs do not differ significantly. Conclusions. FG and non-FG BGGs differ from one another in terms of their morphological properties and Kormendy relation, suggesting they have had different formation histories. However, it is not possible to trace differences in their stellar populations or in their large-scale distributions. © The Authors 2023., F.D. acknowledges support from CNES. I.M. acknowledges financial support from the State Agency for Research of the Spanish MCIU, through the “Center of Excellence Severo Ochoa” award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709), and through PID2019-106027GB-C41. F.S. acknowledges support from a CNES Postdoctoral Fellowship. This work is based on data obtained as part of UNIONS (initially CFIS), using data from a CFHT large program of the National Research Council of Canada and the French Centre National de la Recherche Scientifique. Based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA Saclay, at the Canada-France-Hawaii Telescope (CFHT) which is operated by the National Research Council (NRC) of Canada, the Institut National des Science de l’Univers (INSU) of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii. Pan-STARRS is a project of the Institute for Astronomy of the University of Hawaii, and is supported by the NASA SSO Near Earth Observation Program under grants 80NSSC18K0971, NNX14AM74G, NNX12AR65G, NNX13AQ47G, NNX08AR22G, and by the State of Hawaii. Funding for the Sloan Digital Sky Survey IV has been provided by the Alfred P. Sloan Foundation, the U.S. Department of Energy Office of Science, and the Participating Institutions. SDSS-IV acknowledges support and resources from the Center for High-Performance Computing at the University of Utah. The SDSS web site is www.sdss.org. SDSS-IV is managed by the Astrophysical Research Consortium for the Participating Institutions of the SDSS Collaboration including the Brazilian Participation Group, the Carnegie Institution for Science, Carnegie Mellon University, the Chilean Participation Group, the French Participation Group, Harvard-Smithsonian Center for Astrophysics. Based in part on observations made at Observatoire de Haute-Provence (CNRS), France. This research has made use of the MISTRAL database, based on observations made at Observatoire de Haute Provence (CNRS), France, with the MISTRAL spectro-imager, and operated at CeSAM (LAM), Marseille, France. Based on observations collected at Centro Astronomico Hispano en Andalucia (CAHA) at Calar Alto, operated jointly by Instituto de Astrofisica de Andalucia (CSIC) and Junta de Andalucia. Based on observations taken with the Nordic Optical Telescope on La Palma (Spain)., With funding from the Spanish government through the "Severo Ochoa Centre of Excellence" accreditation (CEX2021-001131-S).

We report on GaN lasers with extremely narrow linewidth (~1MHz) at ‘magic wavelengths’ for cold-atom quantum sensors and optical atomic clocks, using extended cavity GaN laser diodes and DFB GaN laser diodes.

Low-surface-brightness galaxies (LSBs) contribute to a significant fraction of all the galaxies in the Universe. Ultra-diffuse galaxies (UDGs) form a subclass of LSBs that has attracted a lot of attention in recent years (although its definition may vary between studies). Although UDGs are found in large numbers in galaxy clusters, groups, and in the field, their formation and evolution are still very much debated. Using a comprehensive set of multiwavelength data from the NGVS (optical), VESTIGE (H$\alpha$ narrowband), and GUViCS (UV) surveys, we studied a sample of 64 diffuse galaxies and UDGs in the Virgo cluster to investigate their formation history. We analyzed the photometric colors and surface-brightness profiles of these galaxies and then compared them to models of galaxy evolution, including ram-pressure stripping (RPS) events to infer any possible strong interactions with the hot cluster gas in the past. While our sample consists mainly of red LSBs, which is typical in cluster environments, we found evidence of a color variation with the cluster-centric distance. Blue, HI-bearing, star-forming diffuse galaxies are found at larger distances from the cluster center than the rest of the sample. The comparison of our models with multifrequency observations suggests that most of the galaxies of the sample might have undergone a strong RPS event in their lifetime, on average 1.6 Gyr ago (with a large dispersion, and RPS still ongoing for some of them). This process resulted in the transformation of initially gas-rich diffuse blue galaxies into gas-poor and red ones that form the dominant population now, the more extreme UDGs having undergone the process in a more distant past on average. The RPS in dense environments could be one of the major mechanisms for the formation of the large number of quiescent UDGs we observe in galaxy clusters., Comment: 57 pages, 14 Figures, accepted for publication in A&A

There have been 77 TNOs discovered to be librating in the distant trans-Neptunian resonances (beyond the 2:1 resonance, at semimajor axes greater than 47.7 au) in four well-characterized surveys: the Outer Solar System Origins Survey (OSSOS) and three similar prior surveys. Here, we use the OSSOS Survey Simulator to measure their intrinsic orbital distributions using an empirical parameterized model. Because many of the resonances had only one or very few detections, j:k resonant objects were grouped by k in order to have a better basis for comparison between models and reality. We also use the Survey Simulator to constrain their absolute populations, finding that they are much larger than predicted by any published Neptune migration model to date; we also find population ratios that are inconsistent with published models, presenting a challenge for future Kuiper Belt emplacement models. The estimated population ratios between these resonances are largely consistent with scattering–sticking predictions, though further discoveries of resonant TNOs with high-precision orbits will be needed to determine whether scattering–sticking can explain the entire distant resonant population or not.

In 1978 and 1979 two infant formulas, Neo-Mull-Soy and Cho-Free, were found to be deficient in chloride. The Centers for Disease Control received reports that hypochloremic metabolic alkalosis (HMA) had developed in 141 children as a result of exposure to these formulas. Thirty-five of these children were examined at 9 and 10 years of age and compared with a group of 32 children who were exposed to the chloride-deficient formulas but were not reported to experience HMA and a group of 61 children who received chloride-sufficient soy formulas in infancy. The control children were matched to the HMA children on sex, race, age, and maternal education. Growth characteristics, performance on the Wechsler Intelligence Scale for Children-Revised (WISC-R), the Boston Naming Test, the Rey-Osterrieth Test, the Clinical Evaluation of Language Fundamentals-Revised (CELF-R), and subtests from several other speech and language tests were compared across the groups. After adjustment for family income and the level of the father's education, significantly lower scores were observed in the HMA children on the WISC-R Arithmetic subtest (mean = 10.5) compared with the soy control children (mean = 12.0, P < .05) and on the WISC-R Coding subtest (mean = 9.0) compared with the soy control children (mean = 10.8, P < .01). All the WISC-R subtest scores were, however, within the normal range. Although no significant differences occurred on the CELF-R between groups, the risk of an HMA child falling below the range expected for a standard population was increased on the CELF-R Composite Total, Receptive, and Expressive Language scores: risk ratios = 2.14, 2.14, and 3.03 respectively. Significant differences were observed between the children exposed, both HMA and non-HMA children, and the soy control children for behavioral problems as determined by the Achenbach Childhood Behavioral Checklist. It is concluded that as a group, children with documented HMA appear to have recovered from their growth failure and have normal cognitive development. They may, however, be at risk for deficits in language skills that require expressive language abilities.

The low-income black family has needs that are not being met by traditional family therapy approaches. This article examines the literature on the effectiveness of typical treatment methods, presents an illustrative case study, and then describes more specialized family therapy models for reaching this population.

This paper describes a diode‐array pulsed spectrometer (DAPS) that performs flash photolysis studies with a time resolution of 10 ns and a spectral resolution of 2.4 nm over a 600‐nm wavelength window in the range of 350–1100 nm. It employs a 1024‐element photodiode‐array detector with high dynamic range and low noise. Laser‐pumped fluorescent dye mixtures are used as a novel, stable light source which enable it to record spectra with a photolimited S/N ratio equivalent to 0.001 abs. units in a single shot. The measuring light distribution can be tailored so that a constant S/N ratio across a spectrum is attainable even in regions of high absorbance. Electrical artifacts from the actinic laser or other discharges do not interfere with the measurement and the effects of scattered actinic light and fluorescence from the sample are minimized. The instrument is simple to build, using mainly standard lab equipment, and easy to maintain and operate.

This paper describes an instrument for conductimetric detection of charged species formed in solution‐phase photochemical reactions in the time region 1 μsec to 100 msec. A low‐voltage pulsed dc polarization technique is employed, and electrochemical complications minimized by pulse reversal. By using state‐of‐the‐art operational amplifiers it is possible to study ion transients as short as 10 nsec, but the present instrument is set up for a 1% settling time of 400 nsec, giving sufficient sensitivity to detect ions in nanomolar concentration and sufficient speed to follow encounter‐limited reactions at millimolar reactant concentrations. The instrument is dc coupled throughout, but employs an automatic zeroing system to refer photoconductance transients to a zero baseline and provide continuous readout of the static conductance.