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An improved model for the effect of correlated Si iii absorption on the one-dimensional Lyman-α forest power spectrum
Full text linkWe present an analysis of Si iii absorption and its effect on the one-dimensional Ly forest power spectrum using the Sherwood–Relics hydrodynamical simulation suite. In addition to oscillations from the Ly – Si iii cross-correlation that are damped towards smaller scales, we find an enhancement in small-scale power that has been ignored in previous studies. We therefore develop a new analytical fitting function that captures two critical effects that have previously been neglected: distinct Ly and Si iii line profiles, and a variable ratio for coeval Ly and Si iii optical depths. In contrast to earlier work, we also predict amplitudes for the Si iii power spectrum and Ly – Si iii cross power spectrum that decrease towards lower redshift due to the hardening metagalactic UV background spectrum at . The fitting function is validated by comparison against multiple simulated data sets at redshifts and wavenumbers s km. Our model has little effect on existing warm dark matter constraints from the Ly forest when adopting a physically motivated prior on the silicon abundance. It will, however, be an essential consideration for future, high precision Ly forest power spectrum measurements
Pedestrian Motion Prediction Evaluation for Urban Autonomous Driving
Full text linkPedestrian motion prediction is a key aspect in any autonomous-driving pipeline, and is required for ensuring safe, accurate, and timely awareness of human agents' possible future trajectories. Autonomous vehicles need to use agent motionprediction information to prevent any possible accidents, and for creating a comfortable and pleasant driving experience for vehicles' passengers as well for pedestrians in vehicles' vicinity. A significant amount of research has been conducted on the topic of agent motion prediction in the fields of robotics, computer vision, and intelligent transportation systems etc. However, a relatively unexplored aspect in the existing literature is the integration of state-of-the-art motion-prediction solutions into existing autonomous driving stacks and evaluating them in real-life conditions rather than on sanitized datasets. In this paper, we analyze a set of selected methods from the literature, and present the perspective obtained by integrating them into an existing autonomous-driving software stack - Autoware Mini - and performing experiments in natural urban conditions in Tartu, Estonia to determine the suitability of conventional motion prediction metrics. Our study should be of value to researchers in autonomous driving or robotics interested in understanding real-world performance of existing state-of-theart pedestrian motion prediction methods. The code, along with instructions on accessing the dataset that we employ, is available at https://github.com/dmytrozabolotnii/autoware_min
Towards resilient renewable energy deployment in Africa through a weather-aware optimization framework
Full text linkRenewable energy deployment in Africa must account for the continent’s pronounced weather variability to ensure reliable electricity supply. Here, we introduce a weather-aware framework that integrates multi-criteria decision analysis with assessments of meteorological variability to optimize renewable site selection. Optimal solar and wind energy locations are identified not only by their highest average yields but also by evaluating generation variability under major climate oscillations, including the Madden–Julian Oscillation modulated by El Niño–Southern Oscillation. In addition, novel synoptic regimes are derived through Self Organising Map cluster analysis, providing further insight into region-specific drivers of variability. Country-level yield estimates reveal the dominant meteorological patterns shaping renewable output and their frequencies of occurrence. Our findings underscore the necessity of accurately forecasting these regimes to enhance system resilience and inform long-term planning. By explicitly linking generation variability to underlying climate drivers, this framework offers a robust pathway for optimizing renewable energy expansion across Africa
Assistive Robotics for Healthy Aging: A Foundational Phenomenological Co-Design Exercise
Full text linkBackground: Assistive robotics for helping older people live well and stay independent has, to date, failed to fulfill its promise: there are few assistive robots in everyday use. In part, this failing can be attributed to inadequate or missing co-design activities that would ensure that these technologies and any services that incorporate them are developed with prospective end users, addressing their actual needs and wants, and not merely for them, and based on lazy assumptions about heterogeneous user groups. Objective: This exercise aimed to address some of these limitations by taking a ``phenomenological snapshot'' of what it means to be an older person in the current sociotechnological context, and making this snapshot, along with the co-design materials developed, available to the wider assistive robotics community to provide solid foundational evidence for steering the development of assistive robotics in more productive directions. Methods: Two rounds of co-design workshops have been conducted with older people and their caregivers, based on an innovative methodology that used personas and speculative designs to explore sensitive everyday difficulties faced by participants and highlight some of their general wishes for and concerns about assistive robotics. The data collected during the workshops were analyzed, and key themes were extracted. Results: Analysis of the workshop data gives access to the lived experience of older people and their caregivers, and their opinions about domestic robotics and assistive technologies more generally. The findings are organized thematically as everyday difficulties, the daily problems faced by older people; ideas for aging better, older people's own suggestions for how their lives could be improved; and living with technology, their preferences and requirements for assistive robots, along with their concerns about what the introduction of robots might mean, both for themselves and for society more widely. Conclusions: We believe that our findings provide solid foundational evidence for the development of assistive robotics for older people. We are in the process of disseminating these results through various channels to the wider assistive robotics community; ultimately, the success of our activities will be demonstrated only through the development of acceptable, useful, and viable assistive robotics for older people
The Diversity of Cold Worlds: Age and Characterization of the Exoplanet COCONUTS-2 b
Full text linkStudying cold brown dwarfs is key to understanding the diverse characteristics of cold giant exoplanets atmospheres. COCONUTS-2 is a wide binary system composed of a T9 brown dwarf and an M3 star, which presents a unique opportunity to characterize a cold benchmark brown dwarf. As part of a JWST program to study the range of physical and atmospheric properties of the coldest brown dwarfs, we obtained NIRSpec G395H spectra (R ∼ 2700, 2.87−5.13 μm) and MIRI F1000W, F1280W, and F1800W photometry for COCONUTS-2 b. In this work, we find a 99% probability of the system belonging to the Corona of Ursa Major moving group (414 ± 23 Myr) using BANYAN Σ and its full kinematics. We also reestimate the astrometry of COCONUTS-2b using the MIRI data. We support this membership with a comparison of the rotation period, metallicity, and C/O ratio of the group with those of the COCONUTS-2 system. We also calculate its bolometric luminosity, which, combined with our age estimation, allows us to derive its mass, effective temperature, surface gravity, and radius with high precision. As a result of our analysis, we support the conclusion that COCONUTS-2 b is a planetary-mass object (7.5 ± 0.4 MJup), which was likely formed via the same mechanism as stars. In addition we compare the JWST spectrum to another object in the sample, J082507.35+280548.5 (0825+2805), a Y0.5 brown dwarf, which is a candidate member of the same moving group, but has a lower mass (3.7 ± 0.2 MJup). We identify absorption feature differences, which could indicate that 0825+2805 has stronger vertical mixing
A search for transit-timing variations in the transiting hot-Jupiter systems HIP 65, NGTS-6, NGTS-10, and WASP-173
Full text linkHot Jupiters are Jupiter-mass planets with orbital periods of less than 10 d. Their short orbital separations make tidal dissipation within the stellar host especially efficient, potentially leading to a measurable evolution of the orbit. One possible manifestation of this is orbital decay, which presents itself observationally through variations in the orbital period and thus times of transit. Here, we select four promising exoplanetary systems for detecting this effect: HIP 65, NGTS-6, NGTS-10, and WASP-173. We present 33 new transit light curves taken with the 1.54 m Danish Telescope, and analyse these alongside photometric data from the Transiting Exoplanet Survey Satellite and transit-timing data from the literature. We construct two ephemeris models for each target: a linear ephemeris and a shrinking orbital period due to tidal decay. The linear ephemeris is preferred for three of the four models – the highest significance for the quadratic ephemeris is over 3 for WASP-173. We compare these results to theoretical predictions for tidal dissipation of gravity waves in radiation zones, and find that wave breaking is predicted only in WASP-173, making rapid decay plausible in this system but unclear in the other three. The sensitivity of transit timings to orbital decay depends on the square of the time interval covered by available observations, so our results establish a useful baseline against which future measurements can be compared. NGTS-6 and NGTS-10 are important objects for future study as they are in the first field to be observed by the upcoming PLATO mission
The Quasar Feedback Survey : Revealing the importance of sensitive radio imaging for AGN identification deeper into the radio-quiet regime
Full text linkWe present new sub-arcsecond (∼0.3–1 arcsec; ∼1–3 kpc) Very Large Array imaging at 1.4 and 6 GHz of 29 opticallyselected [O iii] luminous (L[OIII] > 1042.1 erg s−1) z < 0.2 quasars drawn from the expanded Quasar Feedback Survey(QFeedS; with L1.4 GHz = 1022.6–1026.3 WHz−1). These 29 new objects occupy the low end of the radio-power distribution(L1.4 GHz=1022.63–1023.45 WHz−1) in the QFeedS sample and are nominally ‘radio quiet’. Despite this, we find widespreadevidence of active galactic nucleus (AGN)-driven synchrotron activity. Nearly ∼ 31 per cent exhibit resolved radio structures on ∼0.1–20 kpc scales consistent with compact jets or wind-driven outflows, and ∼ 90 per cent display steep spectra(α −1) indicative of optically thin synchrotron emission. Combining morphology, spectral index, and brightness temperature diagnostics, at least ∼ 38 per cent of the sample show clear AGN signatures that cannot be explained by starformation alone. These constitute the first results from the expanded QFeedS (now 71 quasars spanning ≈ 4 dex in radiopower) and demonstrate that compact low-power jets and AGN shocks are common deep inside the radio-quiet regime.A thorough understanding of feedback processes from quasars, deep into the ‘radio-quiet’ regime, will be obtained byconnecting these high-resolution radio observations with multiwavelength observations
Stellar Populations in the Extreme Outer Halo of the Spiral Galaxy M96
Full text linkWe use deep Hubble Space Telescope imaging to study stellar populations in the outer halo of the spiral galaxy M96, located in the dynamically active Leo I galaxy group. Our imaging targets two fields at a projected distance of 50 kpc from the galaxy’s center, with a 50% photometric completeness limit of F814W = 28.0—nearly 2 magnitudes below the tip of the red giant branch (RGB). In both fields, we clearly detect red giant stars in M96’s halo, with a space density that corresponds to an equivalent broadband surface brightness of μV ≈ 31.7 mag arcsec−2. We find little evidence for any differences in the spatial density or color of the RGB stars in the two fields. Using isochrone matching, we derive a median metallicity for the red giants of [M/H] = −1.36, with an interquartile spread of ± 0.75 dex. Adopting a power-law radial density profile, we also derive a total halo mass of Mh=7.8−4.9+17.4×109 M⊙, implying a stellar halo mass fraction of M*, halo/M*, tot≈15−9+33 %—on the high end for spiral galaxies, but with significant uncertainty. Finally, we find that M96 appears offset from the stellar halo mass–metallicity relationship for spirals, with a halo that is distinctly metal-poor for its halo mass. While a variety of systematic effects could have conspired to drive M96 off this relationship, if confirmed our results may argue for a markedly different accretion history for M96 compared to other spirals in the nearby Universe
Jewish Sopranos in Germany: A study of Jewish-Muslim Cooperation in the Post-Migrant Television Series "The Zweiflers"
Full text linkIn an extremely critical public sphere surrounding Jewish-Muslim relations in Germany, the multi-award-winning miniseries The Zweiflers has uniquely navigated this intense scrutiny, depicting a nuanced subplot of Jewish-Muslim coexistence. Inspired by HBO's The Sopranos, the series centres on the Zweifler family, exploring their complex intergenerational dynamics, transnational diasporic ties, and alleged connections to Frankfurt's underworld. While initially lauded for its portrayal of a modern German-Jewish identity, this article takes a closer look at the significant theme of Jewish-Muslim cooperation in post-war Germany. Drawing on ethnographic research conducted in Frankfurt's Bahnhofsviertel (train station district), where the series was filmed, The Zweiflers is critically analysed and compared with insights from that long-term fieldwork. This analysis is further contextualized by engaging with the crucial works of diasporic artists and post-migrant filmmakers, alongside scholarship on urban multiculture and anti-essentialist concepts in sociology and cultural studies. The Jewish-Muslim relationships depicted in the series are not merely fictional; they reflect real, historically evolved partnerships characterized by a collective will to overcome contradictions. This nuanced depiction counters static assumptions about community relations often found in the polarized debates surrounding the Israeli-Palestinian conflict, offering a vital contribution to understanding contemporary German society
Skilled for Whom? Immigration Policy, Racial Capitalism, and the Reproduction of Inequality in Britain
Full text linkThis paper examines the UK's 2025 Immigration White Paper as a critical site for understanding how immigration policy functions as an instrument of racial capitalism. Drawing on Critical Race Theory, the theory of social reproduction, and intersectionality, it interrogates how the state's construction of the ‘skilled migrant’ operates as a racially coded category that privileges whiteness, anglocentric credentials, and neoliberal norms of value. Rather than treating the White Paper as a discrete policy episode, the analysis situates it within a longer genealogy of immigration governance that reproduces structural inequalities across higher education and graduate employment. By tracing how migrant ‘worthiness’ is encoded through racialised and classed proxies—such as language fluency, academic credentials, and salary thresholds—the paper contributes to wider sociological debates on bordering, credentialism, and state racial formation. It demonstrates that the British state's discourse of ‘merit’ and ‘skill’ is inseparable from exclusionary practices that undermine the promise of equal opportunity for racialised citizens and migrants alike. The paper concludes by advancing a forward-looking framework for understanding policy as both a site of intervention and a generator of symbolic and material hierarchies