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1. The Deepest GLIMPSE of a Dense Gas Cocoon Enshrouding a Little Red Dot

   https://doi.org/10.3847/1538-4357/ae4ed7  

   Kokorev, Vasily; Chisholm, John; Naidu, Rohan P; Fujimoto, Seiji; Atek, Hakim; Brammer, Gabriel; Finkelstein, Steven L; Akins, Hollis B; Berg, Danielle A; Furtak, Lukas J; et al (June 2026, The Astrophysical Journal)

   Abstract The detection of strong Balmer breaks and absorption features in Little Red Dots (LRDs) suggests they host active galactic nuclei embedded within dense gas envelopes, potentially powered by super-Eddington accretion. We present GLIMPSE-17775, a luminous (L_bol ∼ 10⁴⁵erg s⁻¹) LRD atz= 3.501 behind Abell S1063 (μ ∼ 2), observed with deep JWST/NIRCam and a ∼20 hr (80 hr delensed) NIRSpec G395M spectrum. The data reveal over 40 emission and absorption features, including a rich forest of low-ionization Feiilines and numerous broad hydrogen recombination transitions. We use this depth to test the dense-gas interpretation through five independent diagnostics. Nearly all permitted lines show exponential wings with consistent FWHM, a signature of Thomson scattering requiringn_e ≳ 10⁸cm⁻³. Adopting this width yieldsM_BH ∼ 10^6.7M_⊙, a factor of 10 lower than Gaussian fits, andλ_Edd ∼ 1.8. Additional diagnostics support the same picture: a pronounced Balmer break (f_ν,4050/f_ν,3670 = 2.0 ± 0.1), enhanced Heiλ7065 andλ10830 with P-Cygni absorption, Bowen-fluorescent Oiλ8446–λ11290 emission requiring Lyβpumping, and 16 Feiilines matching fluorescence models. These features indicate a dense (n ∼ 10⁸cm⁻³), partially ionized cocoon where scattering and fluorescence dominate line formation, providing strong evidence that at least some LRDs are powered by super-Eddington black hole growth in the early Universe. 

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2. A GLIMPSE into the UV Continuum Slopes of the Faintest Galaxies in the Epoch of Reionization

   https://doi.org/10.3847/1538-4357/ae5246  

   Jecmen, Michelle C; Chisholm, John; Atek, Hakim; Kokorev, Vasily; Endsley, Ryan; Chemerynska, Iryna; Furtak, Lukas J; Pan, Richard; Fujimoto, Seiji; Naidu, Rohan P; et al (April 2026, The Astrophysical Journal)

   Abstract As observations have yet to constrain the ionizing properties of the faintest (M_UV≳ −16) galaxies, their contribution to cosmic reionization remains unclear. The rest-frame ultraviolet (UV) continuum slope (β) is a powerful diagnostic of stellar populations and one of the few feasible indicators of the escape fraction of ionizing photons (f_esc) for such faint galaxies at high redshift. Leveraging ultradeep JWST/NIRCam GLIMPSE imaging of the strong lensing field Abell S1063, we estimate the UV continuum slopes of 553 galaxies atz> 6 with absolute magnitudes down toM_UV≃ −12.5. We find a modest evolution ofβwith redshift and a flattening in theβ–M_UVrelation such that galaxies fainter thanM_UV∼ −16.5 no longer exhibit the bluest UV slopes. The 136 ultrafaint galaxies withM_UV> −16 are a diverse population encompassing dusty (30%), old (15%), and low-mass (50%) galaxies. We apply the empiricalβ–f_escrelation from local Lyman continuum leakers, finding the meanf_escpeaks at ∼20% atM_UV= −16.5 and declines towards fainter galaxies, while remaining consistent withf_esc= 14% within the uncertainties, in agreement with recent radiative transfer simulations. Incorporating GLIMPSE constraints on the UV luminosity function, ionizing photon production efficiency, and escape fractions produces a reionization history consistent with independent observational constraints. Our results indicate galaxies with anM_UVbetween −18 and −14 supplied ∼60% of the ionizing photons to cosmic reionization, while the lowerf_escof fainter galaxies produces a natural cutoff in the ionizing photon production rate density. 

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3. Evaluating the Photosynthetic Response of Perovskite-based Solar Cells for Greenhouse Applications

   https://doi.org/10.21273/JASHS05528-25  

   Persons, Parker Egan; van_Iersel, Marc W; Ullrich, Susanne; Zhan, Jie; Anh_Ngo, Tu; Duc_Nguyen, Tho; Severns, Paul M; Ferrarezi, Rhuanito Soranz (March 2026, J. Amer. Soc. Hort. Sci.)

   Greenhouses have been widely used to grow lettuce (Lactuca sativa) for commercial markets worldwide, but electricity is a major input cost at these facilities when supplemental lighting is needed. To improve sustainability, solar energy, especially photovoltaic technologies, is being investigated as an alternative power source. One promising solution is the use of semi-transparent perovskite solar cells, which transmit high levels of extended photosynthetic active radiation (ePAR), the light needed for photosynthesis, while generating electricity. This study quantified the effects of perovskite solar systems on lettuce photosynthetic rates under short-term exposure. Two trials that explored the photosynthetic capacity of ‘Green Towers’ lettuce underneath methylammonium lead iodide (MAPbI₃), MAPbI_2.25Br_0.75, MAPbI_1.5Br_1.5, MAPbI_0.75Br_2.25, and methylammonium lead bromide (MAPbBr₃) thin films, each with distinct energy bandgap and corresponding transmission spectra, were conducted. Light-response curves were created by exposing lettuce to increasing light intensities, and nonlinear regression was used to determine the maximum quantum yield of photosystem II (F_v/F_m) and maximum net photosynthesis rate (P_Nmax) under the perovskite samples. In the first trial, lettuce photosynthesis was measured under MAPbI₃perovskite samples at 0.06, 0.12, and 0.24 M concentrations, with increasing concentrations producing thicker films that reduced spectral transparency. In the second trial, lettuce photosynthesis was measured under MAPbI₃, MAPbI_2.25Br_0.75, MAPbI_1.5Br_1.5, MAPbI_0.75Br_2.25, and MAPbBr₃at a concentration of 0.06 M. There were no differences inF_v/F_mandP_Nmaxof lettuce underneath the perovskite samples at the concentrations of 0.06 M or 0.12 M in both trials (P >0.05). TheP_Nmaxwas greater under 0.24 M MAPbI₃perovskite in the first trial, highlighting its potential for agrivoltaic applications. Semi-transparent perovskites show promise as greenhouse glazing materials. 

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4. Measurements of F ₁ ‐ Region Ionosphere State Variables at Arecibo Through Quasi Height‐Independent Exhaustive Fittings of the Incoherent Scatter Ion‐Line Spectra

   https://doi.org/10.1029/2024JA032620  

   Li, Yanlin; Zhou, Qihou (November 2024, Journal of Geophysical Research: Space Physics)

   Abstract We discuss an exhaustive search approach to fit the incoherent scatter spectrum (ISS) in the F₁‐region for molecular ion fraction (f_m), ion temperature (T_i), and electron temperature (T_e). The commonly used “full profile” approach for F₁‐region measurements parameterizes the molecular ion fraction as a function of altitude and fits all the related heights for the state variables. In our approach, we fit the ISS at each height forf_m,T_i,T_e, and ion velocity (V_i) independently. Our exhaustive search method finds all the major local minima at each altitude. Although a parameterized function is used to guide the algorithm in finding the best solution, the fitting parameters retain their local characteristics. Despite that fittingf_m,T_i, andT_ewithout constraints requires Doppler shift to be accurately determined and the ISS signal‐to‐noise ratio higher than the full‐profile method, simulations show thatT_i,T_e, andf_mcan be recovered within a few percent accuracy with a moderate signal‐to‐noise ratio. We apply the exhaustive search approach to the Arecibo high‐resolution incoherent scatter radar data taken on 13 September 2014. The derived ion and electron temperatures are sensitive enough to reveal thermosphere gravity waves commonly seen in the electron density previously. Our method is more robust than previous height‐independent fitting methods. Comparison with another Arecibo program indicates our results are likely more accurate. Simultaneous high‐resolution measurements ofT_i,T_e,f_m,V_i, and electron concentration (N_e) in our approach open new opportunities for synergistic studies of the F₁‐region dynamics and chemistry. 

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5. Bootstrapping M-theory orbifolds

   https://doi.org/10.1007/JHEP06(2024)001  

   Chester, Shai M; Pufu, Silviu S; Wang, Yifan; Yin, Xi (June 2024, Journal of High Energy Physics)

   A<sc>bstract</sc> We analyze correlation functions of SU(k) × SU(2)_Fflavor currents in a family of three-dimensional$$ \mathcal{N} $$ $N$ = 4 superconformal field theories, combining analytic bootstrap methods with input from supersymmetric localization. Via holographic duality, we extract gluon and graviton scattering amplitudes of M-theory on AdS₄×S⁷/ℤ_kwhich contains a ℂ²/ℤ_korbifold singularity. From these results, we derive aspects of the effective description of M-theory on the orbifold singularity beyond its leading low energy limit. We also determine a threshold correction to the holographic correlator from the combined contribution of two-loop gluon and tree-level bulk graviton exchange. 

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