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We examine Abell 1689 non-parametrically, combining strongly lensed Hubble Space Telescope images and weak distortions from wider field Subaru imaging. Our model incorporates member galaxies to improve the lens solution. By adding luminosity-scaled member galaxy deflections to our smooth grid, we can derive meaningful solutions with sufficient accuracy to permit the identification of our own strongly lensed images, so our model becomes self-consistent. We identify 11 new multiply lensed system candidates and clarify previously ambiguous cases, in the deepest optical and near-infrared data to date from Hubble and Subaru. Our improved spatial resolution brings up new features not seen when the weak and strong lensing effects are used separately, including clumps and filamentary dark matter around the main halo. Our treatment means we can obtain an objective mass ratio between the cluster and galaxy components. We find a typical mass-to-light ratios of M/LB = 21 ± 14 inside the r < 1 arcmin region. Our model independence means we can objectively evaluate the competitiveness of stacking cluster lenses for defining the geometric lensing–distance–redshift relation in a model-independent way. [ABSTRACT FROM AUTHOR]

We present the supernova (SN) sample and Type-Ia SN (SN Ia) rates from the Cluster Lensing And Supernova survey with Hubble (CLASH). Using the Advanced Camera for Surveys and the Wide Field Camera 3 on the Hubble Space Telescope (HST), we have imaged 25 galaxy-cluster fields and parallel fields of non-cluster galaxies. We report a sample of 27 SNe discovered in the parallel fields. Of these SNe, ∼13 are classified as SN Ia candidates, including four SN Ia candidates at redshifts z > 1.2. We measure volumetric SN Ia rates to redshift 1.8 and add the first upper limit on the SN Ia rate in the range 1.8 < z < 2.4. The results are consistent with the rates measured by the HST/GOODS and Subaru Deep Field SN surveys. We model these results together with previous measurements at z < 1 from the literature. The best-fitting SN Ia delay-time distribution (DTD; the distribution of times that elapse between a short burst of star formation and subsequent SN Ia explosions) is a power law with an index of , where the statistical uncertainty is a result of the 68% and 95% (in parentheses) statistical uncertainties reported for the various SN Ia rates (from this work and from the literature), and the systematic uncertainty reflects the range of possible cosmic star-formation histories. We also test DTD models produced by an assortment of published binary population synthesis (BPS) simulations. The shapes of all BPS double-degenerate DTDs are consistent with the volumetric SN Ia measurements, when the DTD models are scaled up by factors of 3-9. In contrast, all BPS single-degenerate DTDs are ruled out by the measurements at >99% significance level. [ABSTRACT FROM AUTHOR]

We present a quintuply lensed z ∼ 6 candidate discovered in the field of the galaxy cluster RXC J2248.7−4431 (z ∼ 0.348) targeted within the Cluster Lensing and Supernova survey with Hubble (CLASH) and selected in the deep Hubble Space Telescope (HST) frontier fields survey. Thanks to the CLASH 16-band HST imaging, we identify the quintuply lensed z ∼ 6 candidate as an optical dropout in the inner region of the cluster, the brightest image having magAB = 24.8 ± 0.1 in the f105w filter. We perform a detailed photometric analysis to verify its high-z and lensed nature. We get as photometric redshift zph ∼ 5.9, and given the extended nature and NIR colours of the lensed images, we rule out low-z early-type and galactic star contaminants. We perform a strong lensing analysis of the cluster, using 13 families of multiple lensed images identified in the HST images. Our final best model predicts the high-z quintuply lensed system with a position accuracy of 0.8 arcsec. The magnifications of the five images are between 2.2 and 8.3, which leads to a delensed UV luminosity of $L_{1600}\sim 0.5L_{1600}^*$ at z = 6. We also estimate the UV slope from the observed NIR colours, finding a steep β = −2.89 ± 0.38. We use singular and composite stellar population SEDs to fit the photometry of the high-z candidate, and we conclude that it is a young (age <300 Myr) galaxy with mass of M ∼ 108 M⊙, subsolar metallicity (Z < 0.2 Z⊙) and low dust content (AV ∼ 0.2–0.4). [ABSTRACT FROM AUTHOR]

We present VIsible Multi-Object Spectrograph (VIMOS) observations of a z ~ 6 galaxy quintuply imaged by the Frontier Fields galaxy cluster RXC J2248.7-4431 (z = 0.348). This sub-L", high-z galaxy has been recently discovered by Monna et al. (2013) using dropout techniques with the 16-band HST photometry acquired as part of the Cluster Lensing And Supernova survey with Hubble (CLASH). Obtained as part of the CLASH-VLT survey, the VIMOS medium-resolution spectra of this source show a very faint continuum between ~8700 Å and ~9300 Å and a prominent emission line at 8643 Å, which can be readily identified with Lyman-α at z = 6.110 ± 0.002. The emission line exhibits an asymmetric profile, with a more pronounced red wing. The rest-frame equivalent width of the line is EW = 79± 10 Å, relatively well constrained thanks to the detection of the UV continuum, which is rarely achieved for a sub-L" galaxy at this redshift. After correcting for magnification, the star formation rate (SFR) estimated from the Lyα line is SFR(Lyα) = 11 M☉ yr-1 and that estimated from the UV data is SFR(UV) = 3 M☉ yr-1. We estimate that the effective radius of the source is Re ≲ 0.4 kpc, which implies a star formation surface mass density ΣSFR > 6 M☉ yr-1 kpc-2 and, using the Kennicutt-Schmidt relation, a gas surface mass density Σgas > 103 M☉ pc-2. Our results support the idea that this magnified, distant galaxy is a young and compact object with luminosity 0.4 L" at z = 6, when the Universe was just 1 Gyr old, with a similar amount of mass in gas and stars. In the spirit of the Frontier Fields initiative, we also publish the redshifts of several multiply imaged sources and other background objects, which will help improving the strong-lensing model of this galaxy cluster. [ABSTRACT FROM AUTHOR]

We report the discovery of seven strongly lensed lyman-break galaxy (LBG) candidates at z ~ 7 detected in hubble Space Telescope Wide Field Camera 3 (WFC3) imaging of A1703. The brightest candidate, called A1703-zD1, has an observed (lensed) magnitude of 24.0 AB (26σ) in the WFC3/IR F160W band, making it 0.2 mag brighter than the z850-dropout candidate recently reported behind the Bullet Cluster and 0.7 mag brighter than the previously brightest known z ~ 7.6 galaxy, A1689-zD1. with a cluster magnification of ~9, this source has an intrinsic magnitude of H160 = 26.4 AB, a strong z850-J125 break of 1.7 mag, and a photometric redshift of z ~ 6.7. Additionally, we find six other bright LBG candidates with H160-band magnitudes of 24.9-26.4, photometric redshifts z ~ 6.4 - 8.8, and magnifications μ ~ 3-40. stellar population fits to the advanced camera for surveys, WFC3/IR, and Spitzer/Infrared Array Camera data for A1703-zD1 and A1703-zD4 yield stellar masses (0.7 - 3.0) x 109 M⊙, stellar ages 5-180 Myr, and star formation rates ~7.8 M⊙ yr-1, and low reddening with AV ≤ 0.7. The source-plane reconstruction of the exceptionally bright candidate A1703-zD1 exhibits an extended structure, spanning ~4 kpc in the z ~ 6.7 source plane, and shows three resolved star-forming knots of radius r ~ 0.4 kpc. [ABSTRACT FROM AUTHOR]

We examine the inner mass distribution of the relaxed galaxy cluster A383 (z = 0.189), in deep 16 band Hubble Space Telescope/ACS+WFC3 imaging taken as part of the Cluster Lensing And Supernova survey with Hubble (CLASH) multi-cycle treasury program. Our program is designed to study the dark matter distribution in 25 massive clusters, and balances depth with a wide wavelength coverage, 2000-16000 Å. to better identify lensed systems and generate precise photometric redshifts. This photometric information together with the predictive strength of our strong-lensing analysis method identifies 13 new multiply lensed images and candidates, so that a total of 27 multiple images of nine systems are used to tightly constrain the inner mass profile gradient, d log Σ/d log r ≃ -0.6 ± 0.1 (r < 160 kpc). We find consistency with the standard distance-redshift relation for the full range spanned by the lensed images, 1.01 < z < 6.03, with the higher-redshift sources deflected through larger angles as expected. The inner mass profile derived here is consistent with the results of our independent weak-lensing analysis of wide-field Subaru images, with good agreement in the region of overlap (~0.7-1 arcmin). Combining weak and strong lensing, the overall mass profile is well fitted by a Navarro-Frenk-White profile with Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed M⊙ h-1 and a relatively high concentration, Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed, which lies above the standard c-M relation similar to other well-studied clusters. The critical radius of A383 is modest by the standards of other lensing clusters, rE ≃ 16 ± 2" (for zs = 2.55), so the relatively large number of lensed images uncovered here with precise photometric redshifts validates our imaging strategy for the CLASH survey. In total we aim to provide similarly high-quality lensing data for 25 clusters. 20 of which are X-ray-selected relaxed clusters, enabling a precise determination of the representative mass profile free from lensing bias. [ABSTRACT FROM AUTHOR]

Objective: To describe the relationship between body mass index (BMI) and body fatness (BF) in youth and to determine the accuracy of the BMI category of overweight as a measure of excessive BF. Methods: 987 school-aged youth were combined into groups between the ages of 5-9 years (pre-adolescent, n=128), 10-12 years (early-adolescent, n=631), and 13-15 years (adolescent, n=228). BMI (kg/m2) was calculated from measured height and weight. International Obesity Task Force BMI centile curves were used to classify youth as overweight. BF was determined using triceps and calf skinfolds (Slaughter, 1989) and overfatness was determined using four criteria (Williams, 1992, Child Growth Foundation, 85th, and 90th percentile of the sample). Prevalence of overweight, sensitivity and specificity of BMI were calculated for all groups. Receiver operator characteristic curves determined optimal BMI cut points for overfatness in early-adolescent boys and girls. Results: Correlations between BMI and BF were significant for all groups (r = 0.80-0.94; P<0.001). The accuracy of BMI as a measure of BF varied between boys and girls. Sensitivity declined across girls' age groups (pre-adolescence through adolescence [0.94, 0.85, 0.65]) and there was no specific trend seen in boys (1.00, 0.77, 0.88). Optimal BMI cut points were developed for early adolescent boys (19.4 kg/m2) and girls (21.4 kg/m2). Conclusion: Although BMI and BF were significantly correlated, the accuracy of BMI decreased in girls and showed no apparent trend in boys. The results suggest optimal, universal cut points for early adolescent boys and girls that do not decrease the accuracy of BMI. [ABSTRACT FROM AUTHOR]

The authors present a concept for an anti-tamper system that dynamically generates a cryptographic key derived from microelectromechanical systems (MEMS) arrays encapsulated within a protected system in a single package. The system provides protection in active and passive states with no battery backup. [ABSTRACT FROM PUBLISHER]