Suchergebnisse

With upcoming (continuum) surveys of high-resolution radio telescopes, detection rates of fast radio bursts (FRBs) might approach 10^5 per sky per day by future extremely large observatories, such as the possible extension of the Square Kilometer Array (SKA) to a phase-2 array. Depending on the redshift distribution of FRBs and using the repeating FRB121102 as a model, we calculate a detection rate of multiply imaged FRBs with their multiply imaged hosts caused by the distribution of galaxy-cluster-scale gravitational lenses of the order of 10-4 per square degree per year for a minimum total flux of the host of 10 μJy at 1.4 GHz for SKA phase 2. Our comparison of estimated detection rates for quasars (QSOs), supernovae (SNe), gamma ray bursts (GRBs), and FRBs shows that multiple images of FRBs could be more numerous than those of GRBs and SNe and as numerous as multiple images of QSOs. Time delays between the multiple images of an FRB break degeneracies in model-based and model-independent lens reconstructions as other time-varying sources do, yet without a microlensing bias, as FRBs are more point-like and have shorter duration times. We estimate the relative imprecision of FRB time-delay measurements to be 10^-10 for time delays on the order of 100 days for galaxy-cluster-scale lenses, yielding more precise (local) lens properties than time delays from the other time-varying sources. Using the lens modelling software Grale, we show the increase in accuracy and precision of the reconstructed scaled surface mass density map of a simulated cluster-scale lens when adding time delays for one set of multiple images to the set of observational constraints. ; We would like to thank Claudio Grillo, Eric Jullo, Julian Merten, Adi Zitrin, and the Galaxy Cluster Group at the Institute for Theoretical Astrophysics for helpful discussions and comments. JW gratefully acknowledges the support by the Deutsche Forschungsgemeinschaft (DFG) WA3547/1-1 and WA3547/1-3. JL acknowledges the use of the computational resources and services provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation - Flanders (FWO) and the Flemish Government-department EWI. DE acknowledges support from the Israel - U.S. Binational Science Foundation, the Israel Science Foundation including an ISF-UGC grant, and the Joan and Robert Arnow Chair of Theoretical Astrophysics.

Context. Local gravitational lensing properties, like convergence and shear, determined at the positions of multiply-imaged background objects, yield valuable information on the smaller-scale lensing matter distribution in the central part of galaxy clusters. Highly distorted multiple images with resolved brightness features like the ones observed in CL0024 allow to study these local lensing properties to tighten the constraints on the properties of dark matter on sub-cluster scale. Aims. We investigate to which precision local magnification ratios, J, ratios of convergences, f , and reduced shears, g = (g1, g2), can be determined model-independently for the five resolved multiple images of the source at zs = 1.675 in CL0024. We also determine if a comparison to the respective results obtained by the parametric modelling program Lenstool and by the non-parametric modelling program Grale can detect biases in the lens models. For these model-based approaches we additionally analyse the influence of the number and location of the constraints from multiple images on the local lens properties determined at the positions of the five multiple images of the source at zs = 1.675. Methods. Our model-independent approach uses a linear mapping between the five resolved multiple images to determine the magnifi- cation ratios, ratios of convergences, and reduced shears at their positions.With constraints from up to six multiple image systems, we generate Lenstool and Grale models using the same image positions, cosmological parameters, and number of generated convergence and shear maps to determine the local values of J, f , and g at the same positions across all methods. Results. All approaches show high agreement on the local values of J, f , and g. We find that Lenstool obtains the tightest confidence bounds even for convergences around one using constraints from six multiple image systems, while the best Grale model is generated only using constraints from all multiple images with resolved brightness features and adding limited small-scale mass corrections. Yet, confidence bounds as large as the values themselves can occur for convergences close to one in all approaches. Conclusions. Our results are in agreement with previous findings, supporting the light-traces-mass assumption and the merger hypothesis for CL0024. Comparing the three different approaches allows to detect modelling biases. Given that the lens properties remain approximately constant over the extension of the image areas covered by the resolvable brightness features, the model-independent approach determines the local lens properties to a comparable precision but within less than a second. ; JW would like to thank Mauricio Carrasco, Matteo Maturi, Massimo Meneghetti, Sven Meyer, Juan Remolina, Sebastian Stapelberg, Rudiger Vaas, and Adi Zitrin for helpful discussions, and Johan Richard for helpful discussions and providing the information on his lens model. JW gratefully acknowledges the support by the Deutsche Forschungsgemeinschaft (DFG) WA3547/1-1. JL acknowledges the use of the computational resources and services provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation - Flanders (FWO) and the Flemish Government - department EWI. NT acknowledges support from the European Research Council in the form of a Consolidator Grant with number 681431.

AbstractConflict frequency in adolescence has been linked to personality and relationship-specific features. However, an integrative investigation of both aspects is lacking. To address this gap, this study used data from 571 individuals in middle adolescence (Study 1; Mage = 15.86, SD = 1.23; 75.8% female) and 233 individuals in late adolescence (Study 2; Mage = 17.17, SD = 1.01; 75.5% female) in Germany, including participants' self-reports on conflict frequency and other-reports provided by parents and peers. Across studies, multigroup models revealed that adolescents' level of neuroticism predicted self- and other-perceived conflict frequency in parent and peer relationships more consistently than agreeableness, while providing no evidence for an interplay between both personality traits. Furthermore, relationship-specific features differentially accounted for individual differences in conflict frequency across relationship types, such that in adolescents' relationships with parents, lower relationship quality related to more frequent conflicts. In peer relationships, higher contact frequency was linked to more frequent conflicts. The present findings highlight the contributions of both personality and relationship-specific features to conflict frequency in adolescence and offer practical guidance for the improvement of adolescents' and their relationship partners' social skills and experiences. All research questions, hypotheses, and analyses of this research were preregistered at the OSF and can be retrieved from: https://osf.io/xmvqd/.

Although it is widely known that reading plays a significant role in mathematics performance, it remains unclear how specific reading component skills and item characteristics are associated with adults' mathematics performance. The aim of this study was to investigate reading component skills (printed vocabulary, sentence processing, passage comprehension), characteristics of mathematics items (picture/table, complex verb forms, number of prepositions, lexical density), and the possible interaction effects thereof on mathematics performance. The sample consisted of 368 German adults (age: M = 50.45; 59% female). Our results showed main effects on performance from adults' reading component skills and item characteristics. Furthermore, interaction effects between passage comprehension and two item characteristics on mathematics performance emerge. Implications include enhancing adults' reading component skills.

Assuming individual differences in the satisfaction of affiliative needs, the authors hypothesize that people maintain friendships differently depending on the number and the quality of their horizontal family relationships, and this relates to differences in subjective well‐being. These predictions were tested in 2 studies involving German adults aged 30 to 86 years. Contrary to previous studies, the authors studied the importance of friends in relation to family relationships and identified friends in participants' networks based on predefined criteria. Results showed that less close relationships with horizontal family were accompanied by greater closeness to friends and vice versa, and this was related to higher well‐being. The findings demonstrate that people shape their relationships in accordance to their social environment, and benefit from doing so by enhanced well‐being.

Whether couples have children or remain childless has largely been associated with individual and couple characteristics. We propose that the broader social network additionally differentiates between parents and childless couples, particularly between involuntarily and voluntarily childless couples. In light of this, we studied social network differences and their interplay with dyadic and individual characteristics in three types of couples with and without children, in a sample of 248 German early-midlife adults ( n = 41 voluntarily childless, n = 35 involuntarily childless, n = 48 traditional parental dyads). A multinomial logistic regression analysis revealed that social network characteristics distinguished between voluntarily and involuntarily childless individuals. Additionally, attitudes toward children differed substantially across types of couples, whereas levels of partnership distress did not. Findings provide new insights into the significance of the social network above and beyond dyadic and individual characteristics in early-midlife couples with and without children.

The authors propose a model of relationship differentiation that is based on two psychological mechanisms, the regulation of emotional closeness and the monitoring of reciprocity. Both combined are expected to define relationship systems of differential reproductive significance: Relative to others, kin relationships are predicted by higher closeness and lower reciprocity, cooperative (non-kin) relationships by lower closeness and higher reciprocity, and partner relationships by both higher closeness and higher reciprocity. These assumptions could be confirmed by two studies involving 455 young adults and 171 middle-aged couples from different family forms (i.e., traditional and patchwork families, involuntary and motivated childless couples). Effects varied primarily due to parental investment such that parental partners become less distinguishable from kin, or, in other words, more like "elected kin". Results highlight the flexibility of relationship differentiation.