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Abstract Population III (Pop III) stars, the first generation of stars formed from primordial gas, played a fundamental role in shaping the early Universe through their influence on cosmic reionization, early chemical enrichment, and the formation of the first galaxies. However, to date, they have eluded direct detection due to their short lifetimes and high redshifts. The launch of the James Webb Space Telescope (JWST) has revolutionized observational capabilities, providing the opportunity to detect Pop III stars via caustic lensing, where strong gravitational lensing magnifies individual stars to observable levels. This prospect makes it compelling to develop accurate models for their spectral characteristics to distinguish them from other stellar populations. Previous studies have focused on computing the spectral properties of nonrotating, zero-age main-sequence (ZAMS) Pop III stars. In this work, we expand upon these efforts by incorporating the effects of stellar rotation and post-ZAMS evolution into spectral calculations. We use the JWST bands and magnitude limits to identify the optimal observing conditions, both for isolated stars, as well as for small star clusters. We find that, while rotation does not appreciably change the observability at ZAMS, the subsequent evolution can significantly brighten the stars, making the most massive ones potentially visible with only moderate lensing. 

Abstract Long-duration gamma-ray bursts (LGRBs), thought to be produced during core-collapse supernovae, may have a prominent neutron component in the outflow material. If present, neutrons can change how photons scatter in the outflow by reducing its opacity, thereby allowing the photons to decouple sooner than if there were no neutrons present. Understanding the details of this process could therefore allow us to probe the central engine of LGRBs, which is otherwise hidden. Here, we present results of the photospheric emission from an LGRB jet, using a combination of relativistic hydrodynamic simulations and radiative transfer postprocessing using Monte Carlo radiation transfer code. We control the size of the neutron component in the jet material by varying the equilibrium electron fractionY_e, and we find that the presence of neutrons in the GRB fireball affects the Band parametersαandE₀, while the picture with theβparameter is less clear. In particular, the break energyE₀is shifted to higher energies. Additionally, we find that increasing the size of the neutron component also increases the total radiated energy of the outflow across multiple viewing angles. Our results not only shed light on LGRBs but are also relevant to short-duration gamma-ray bursts associated with binary neutron star mergers due to the likelihood of a prominent neutron component in such systems. 

Abstract To fulfill their conservation potential and provide safeguards for biodiversity, marine protected areas (MPAs) need coordinated research and monitoring for informed management through effective evaluation of ecosystem dynamics. However, coordination is challenging, often due to knowledge gaps caused by inadequate access to data and resources, compounded by insufficient communication between scientists and managers. We propose to use the world's largest MPA in the Ross Sea, Antarctica as a model system to create a comprehensive framework for an interdisciplinary network supporting research and monitoring that could be implemented in other remote large‐scale international MPAs. Our proposed framework has three key components: (i) policy engagement, including delineation of policy needs and ecosystem metrics to assess MPA effectiveness; (ii) community partner engagement to elevate diverse voices, build trust, and share resources; and (iii) integrated science comprising three themes. These themes are: advancement of data science and cyberinfrastructure to facilitate data synthesis and sharing; biophysical modeling towards understanding ecosystem changes and uncertainties; and execution of observational and process studies to address uncertainties and evaluate ecosystem metrics. This proposed framework can improve MPA implementation by generating policy‐relevant science through this coordinated network, which can in turn improve MPA effectiveness in the Ross Sea and beyond.