The Astrophysical Journal Letters最新文献

{"title":"Ionized Gas Kinematics with FRESCO: An Extended, Massive, Rapidly Rotating Galaxy at z = 5.4","authors":"Erica Nelson, Gabriel Brammer, Clara Giménez-Arteaga, Pascal A. Oesch, Rohan P. Naidu, Hannah Übler, Jasleen Matharu, Alice E. Shapley, Katherine E. Whitaker, Emily Wisnioski, Natascha M. Förster Schreiber, Renske Smit, Pieter van Dokkum, John Chisholm, Ryan Endsley, Abigail I. Hartley, Justus Gibson, Emma Giovinazzo, Garth Illingworth, Ivo Labbe, Michael V. Maseda, Jorryt Matthee, Alba Covelo Paz, Sedona H. Price, Naveen A. Reddy, Irene Shivaei, Andrea Weibel, Stijn Wuyts, Mengyuan Xiao, Stacey Alberts, William M. Baker, Andrew J. Bunker, Alex J. Cameron, Stephane Charlot, Daniel J. Eisenstein, Anna de Graaff, Zhiyuan Ji, Benjamin D. Johnson, Gareth C. Jones, Roberto Maiolino, Brant Robertson, Lester Sandles, Katherine A. Suess, Sandro Tacchella, Christina C. Williams and Joris Witstok","doi":"10.3847/2041-8213/ad7b17","DOIUrl":"https://doi.org/10.3847/2041-8213/ad7b17","url":null,"abstract":"With the remarkable sensitivity and resolution of JWST in the infrared, measuring rest-optical kinematics of galaxies at z > 5 has become possible for the first time. This study pilots a new method for measuring galaxy dynamics for highly multiplexed, unbiased samples by combining FRESCO NIRCam grism spectroscopy and JADES medium-band imaging. Here we present one of the first JWST kinematic measurements for a galaxy at z > 5. We find a significant velocity gradient, which, if interpreted as rotation, yields Vrot = 305 ± 70 km s−1, and we hence refer to this galaxy as Twister-z5. With a rest-frame optical effective radius of re = 2.25 kpc, the high rotation velocity in this galaxy is not due to a compact size, as may be expected in the early Universe, but rather to a high total mass, . This is a factor of roughly 10× higher than the stellar mass within re. We also observe that the radial Hα equivalent width profile and the specific star formation rate map from resolved stellar population modeling are centrally depressed by a factor of ∼1.5 from the center to re. Combined with the morphology of the line-emitting gas in comparison to the continuum, this centrally suppressed star formation is consistent with a star-forming disk surrounding a bulge growing inside out. While large, rapidly rotating disks are common to z ∼ 2, the existence of one after only 1 Gyr of cosmic time, shown for the first time in ionized gas, adds to the growing evidence that some galaxies matured earlier than expected in the history of the Universe.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142718232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Solar System Migration Points to a Renewed Concept: Galactic Habitable Orbits","authors":"Junichi Baba, Takuji Tsujimoto and Takayuki R. Saitoh","doi":"10.3847/2041-8213/ad9260","DOIUrl":"https://doi.org/10.3847/2041-8213/ad9260","url":null,"abstract":"Astrophysical evidence suggests that the Sun was born near 5 kpc from the Galactic center, within the corotation radius of the Galactic bar, around 6–7 kpc. This presents challenges for outward migration due to the Jacobi energy constraint, preventing stars from easily overcoming the corotation barrier. In this study, we use test particle simulations to explore two possible migration pathways for the Sun: a “trapped” scenario, where the Sun's orbit was influenced by a slowing Galactic bar, and an “untrapped” scenario driven by dynamic spiral arms. Our results demonstrate that both mechanisms can explain how the Sun migrated from its birth radius (≈5 kpc) to its current orbital radius around 8.5–9 kpc. Furthermore, we investigate the environmental changes experienced by the Sun along these migration pathways, focusing on variations in radiation hazards and comet fluxes, which may have impacted planetary habitability. These findings highlight the dynamic nature of galactic habitability, emphasizing that the path a star takes within the Milky Way can significantly affect its surrounding environment and the potential for life. We propose a new concept of “Galactic habitable orbits,” which accounts for evolving galactic structures and their effects on stellar and planetary systems. This work contributes to a deeper understanding of the solar system's migration and its implications for habitability within the Milky Way.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"99 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142718375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Composition and Provenance of the Chang′e-6 Lunar Samples: Insights from the Simulation of the Impact Gardening Process","authors":"Yanze Su, Luyuan Xu, Meng-Hua Zhu and Xing-Li Cui","doi":"10.3847/2041-8213/ad8f3b","DOIUrl":"https://doi.org/10.3847/2041-8213/ad8f3b","url":null,"abstract":"In 2024 June, China’s Chang′e-6 (CE-6) mission successfully returned 1935.3 grams of samples from the lunar farside for the first time. The origin and composition of the unique samples could offer valuable insights into fundamental questions on the Moon’s evolutional history. Besides the local materials of mare basalts, a certain quantity of foreign ejecta materials are expected in the samples, while their percentage was mostly overestimated since the influence of impact gardening was not fully considered. In this study, we model the impact gardening process surrounding the CE-6 landing site by numerical simulations. Our simulations show that impact gardening played a key role in overturning the local materials and diluting the foreign ones in the top-meters-deep layer at the landing site. About 90% of the CE-6 drilled samples, which were sampled within the top ∼1 m deep layer, are predicted to be the local intermediate-Ti mare basalts originating in the deeper area of 1–60 m, and the underlying low-Ti basalts may make up <1%. The foreign materials in the CE-6 drilled samples likely constitute a minor portion, with an abundance of ∼3.0%. As the primary contributor (∼2.1%) of foreign materials, Chaffee S ejecta may contain lunar mantle materials excavated by the South Pole–Aitken basin.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"81 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142753227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"GRB 240529A: A Tale of Two Shocks","authors":"Tian-Rui Sun, Jin-Jun Geng, Jing-Zhi Yan, You-Dong Hu, Xue-Feng Wu, Alberto J. Castro-Tirado, Chao Yang, Yi-Ding Ping, Chen-Ran Hu, Fan Xu, Hao-Xuan Gao, Ji-An Jiang, Yan-Tian Zhu, Yongquan Xue, Ignacio Pérez-García, Si-Yu Wu, Emilio Fernández-García, María D. Caballero-García, Rubén Sánchez-Ramírez, Sergiy Guziy, I. Olivares, Carlos Jesus Pérez del Pulgar, A. Castellón, S. Castillo, Ding-Rong Xiong, Shashi B. Pandey, David Hiriart, Guillermo García-Segura, William H. Lee, I. M. Carrasco-García, Il H. Park, S. Jeong, Petrus J. Meintjes, Hendrik J. van Heerden, Antonio Martín-Carrillo, Lorraine Hanlon, Bin-Bin Zhang, L. Hernández-García, Maria Gritsevich, Andrea Rossi, Elisabetta Maiorano, Felice Cusano, Paolo D’Avanzo, Matteo Ferro, Andrea Melandri, Massimiliano De Pasquale, Riccardo Brivio, Min Fang, Lu-Lu Fan, Wei-Da Hu, Zhen Wan, Lei Hu, Ying-Xi Zuo, Jin-Long Tang, Xiao-Ling Zhang, Xian-Zhong Zheng, Bin Li, Wen-Tao Luo, Wei Liu, Jian Wang, Hong-Fei Zhang, Hao Liu, Jie Gao,..","doi":"10.3847/2041-8213/ad85da","DOIUrl":"https://doi.org/10.3847/2041-8213/ad85da","url":null,"abstract":"Thanks to the rapidly increasing time-domain facilities, we are entering a golden era of research on gamma-ray bursts (GRBs). In this Letter, we report our observations of GRB 240529A with the Burst Optical Observer and Transient Exploring System, the 1.5 m telescope at Observatorio de Sierra Nevada, the 2.5 m Wide Field Survey Telescope of China, the Large Binocular Telescope, and the Telescopio Nazionale Galileo. The prompt emission of GRB 240529A shows two comparable energetic episodes separated by a quiescence time of roughly 400 s. Combining all available data on the GRB Coordinates Network, we reveal the simultaneous apparent X-ray plateau and optical rebrightening around 103–104 s after the burst. Rather than the energy injection from the magnetar as widely invoked for similar GRBs, the multiwavelength emissions could be better explained as two shocks launched from the central engine separately. The optical peak time and our numerical modeling suggest that the initial bulk Lorentz factor of the later shock is roughly 50, which indicates that the later jet should be accretion driven and have a higher mass loading than a typical one. The quiescence time between the two prompt emission episodes may be caused by the transition between different accretion states of a central magnetar or black hole, or the fallback accretion process. A sample of similar bursts with multiple emission episodes in the prompt phase and sufficient follow-up could help to probe the underlying physics of GRB central engines.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142690667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Discovery of a Rare Group of Dwarf Galaxies in the Local Universe","authors":"Sanjaya Paudel, Cristiano G. Sabiu, Suk-Jin Yoon, Pierre-Alain Duc, Jaewon Yoo and Oliver Müller","doi":"10.3847/2041-8213/ad8f3c","DOIUrl":"https://doi.org/10.3847/2041-8213/ad8f3c","url":null,"abstract":"We report the discovery of a rare isolated group of five dwarf galaxies located at z = 0.0086 (D = 36 Mpc). All member galaxies are star forming, blue, and gas rich, with g − r indices ranging from 0.2 to 0.6 mag, and two of them show signs of ongoing mutual interaction. The most massive member of the group has a stellar mass that is half of the Small Magellanic Cloud stellar mass, and the median stellar mass of the group members is 7.87 × 107M☉. The derived total dynamical mass of the group is Mdyn = 6.02 × 1010M☉, whereas its total baryonic mass (stellar + H i) is 2.6 × 109M☉, which gives us the dynamical to baryonic mass ratio of 23. Interestingly, all galaxies found in the group are aligned along a straight line in the plane of the sky. The observed spatial extent of the member galaxies is 154 kpc, and their relative line-of-sight velocity span is within 75 km s−1. Using the spatially resolved optical spectra provided by the Dark Energy Spectroscopic Instrument early data release, we find that three group members share a common rotational direction. With these unique properties of the group and its member galaxies, we discuss the possible importance of such a system in the formation and evolution of dwarf galaxy groups and in testing the theory of large-scale structure formation.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142671011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Limits on Planetary-mass Primordial Black Holes from the OGLE High-cadence Survey of the Magellanic Clouds","authors":"Przemek Mróz, Andrzej Udalski, Michał K. Szymański, Igor Soszyński, Paweł Pietrukowicz, Szymon Kozłowski, Radosław Poleski, Jan Skowron, Krzysztof Ulaczyk, Mariusz Gromadzki, Krzysztof Rybicki, Patryk Iwanek, Marcin Wrona and Mateusz J. Mróz","doi":"10.3847/2041-8213/ad8e68","DOIUrl":"https://doi.org/10.3847/2041-8213/ad8e68","url":null,"abstract":"Observations of the Galactic bulge revealed an excess of short-timescale gravitational microlensing events that are generally attributed to a large population of free-floating or wide-orbit exoplanets. However, in recent years, some authors suggested that planetary-mass primordial black holes (PBHs) comprising a substantial fraction (1%–10%) of the dark matter in the milky Way may be responsible for these events. If that was the case, a large number of short-timescale microlensing events should also be seen toward the Magellanic Clouds. Here, we report the results of a high-cadence survey of the Magellanic Clouds carried out from 2022 October through 2024 May as part of the Optical Gravitational Lensing Experiment. We observed almost 35 million source stars located in the central regions of the Large and Small Magellanic Clouds and found only one long-timescale microlensing event candidate. No short-timescale events were detected despite high sensitivity to such events. That allows us to infer the strongest available limits on the frequency of planetary-mass PBHs in dark matter. We find that PBHs and other compact objects with masses from 1.4 × 10−8M⊙ (half of the Moon mass) to 0.013 M⊙ (planet/brown dwarf boundary) may comprise at most 1% of dark matter. That rules out the PBH origin hypothesis for the short-timescale events detected toward the Galactic bulge and indicates they are caused by the population of free-floating or wide-orbit planets.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"15 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142673328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Flattest Infrared Extinction Curve in Four Isolated Dense Molecular Cloud Cores","authors":"Jun Li, 军 李, Bingqiu Chen, 丙秋 陈, Biwei Jiang, 碧沩 姜, He Zhao, 赫 赵, Botao Jiang, 博韬 江, Xi Chen and 曦 陈","doi":"10.3847/2041-8213/ad9025","DOIUrl":"https://doi.org/10.3847/2041-8213/ad9025","url":null,"abstract":"The extinction curve of interstellar dust in the dense molecular cloud cores is crucial for understanding dust properties, particularly size distribution and composition. We investigate the infrared extinction law in four nearby isolated molecular cloud cores—L429, L483, L673, and L1165—across the 1.2–8.0 μm wavelength range, using deep near-infrared and mid-infrared photometric data from UKIRT Infrared Deep Sky Survey and Spitzer Space Telescope. These observations probe an unprecedented extinction depth, reaching AV ∼ 40–60 mag in these dense cloud cores. We derive color-excess ratios E(K − λ)/E(H − K) by fitting color–color diagrams of (K − λ) versus (H − K), which are subsequently used to calculate the extinction law Aλ/AK. Our analysis reveals remarkably similar and exceptionally flat infrared extinction curves for all four cloud cores, exhibiting the most pronounced flattening reported in the literature to date. This flatness is consistent with the presence of large dust grains, suggesting significant grain growth in dense environments. Intriguingly, our findings align closely with the Astrodust model for a diffuse interstellar environment proposed by Hensley and Draine. This agreement between dense core observations and a diffuse medium model highlights the complexity of dust evolution and the need for further investigation into the processes governing dust properties in different interstellar environments.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142673329","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Extreme Low-mass End of the Mass–Metallicity Relation at z ∼ 7","authors":"Iryna Chemerynska, Hakim Atek, Pratika Dayal, Lukas J. Furtak, Robert Feldmann, Jenny E. Greene, Michael V. Maseda, Themiya Nanayakkara, Pascal A. Oesch, Seiji Fujimoto, Ivo Labbé, Rachel Bezanson, Gabriel Brammer, Sam E. Cutler, Joel Leja, Richard Pan, Sedona H. Price, Bingjie Wang, John R. Weaver and Katherine E. Whitaker","doi":"10.3847/2041-8213/ad8dc9","DOIUrl":"https://doi.org/10.3847/2041-8213/ad8dc9","url":null,"abstract":"The mass–metallicity relation provides crucial insights into the baryon cycle in galaxies and strong constraints on galaxy formation models. We use JWST NIRSpec observations from the UNCOVER program to measure the gas-phase metallicity in a sample of eight galaxies during the epoch of reionization at z = 6–8. Thanks to the strong lensing of the galaxy cluster Abell 2744, we are able to probe extremely low stellar masses between 106 and 108M⊙. Using strong-line diagnostics and the most recent JWST calibrations, we derive extremely low oxygen abundances in the range of 12 + log(O/H) = 6.7–7.8. By combining this sample with more massive galaxies at similar redshifts, we derive a best-fit relation of 12 + log(O/H) = × , which becomes steeper than determinations at z ∼ 3–6 toward low-mass galaxies. Our results show a clear redshift evolution in the overall normalization of the relation, galaxies at higher redshift having significantly lower metallicities at a given mass. A comparison with theoretical models provides important constraints on which physical processes, such as metal mixing, star formation or feedback recipes, are important in reproducing the observations. Additionally, these galaxies exhibit star formation rates that are higher by a factor of a few to tens compared to extrapolated relations at similar redshifts or theoretical predictions of main-sequence galaxies, pointing to a recent burst of star formation. All these observations are indicative of the highly stochastic star formation and interstellar medium enrichment expected in these low-mass systems, suggesting that feedback mechanisms in high-z dwarf galaxies might be different from those in place at higher masses.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"74 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142670347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"She’s Got Her Mother’s Hair: Unveiling the Origin of Black Hole Magnetic Fields through Stellar to Collapsar Simulations","authors":"Ore Gottlieb, Mathieu Renzo, Brian D. Metzger, Jared A. Goldberg and Matteo Cantiello","doi":"10.3847/2041-8213/ad8563","DOIUrl":"https://doi.org/10.3847/2041-8213/ad8563","url":null,"abstract":"Relativistic jets from a Kerr black hole (BH) following the core collapse of a massive star (“collapsar”) is a leading model for gamma-ray bursts (GRBs). However, the two key ingredients for a Blandford–Znajek-powered jet—rapid rotation and a strong magnetic field—seem mutually exclusive. Strong fields in the progenitor star’s core transport angular momentum outward more quickly, slowing down the core before collapse. Through innovative multidisciplinary modeling, we first use MESA stellar evolution models followed to core collapse to explicitly show that the small length scale of the instabilities—likely responsible for angular momentum transport in the core (e.g., Tayler–Spruit)—results in a low net magnetic flux fed to the BH horizon, far too small to power GRB jets. Instead, we propose a novel scenario in which collapsar BHs acquire their magnetic “hair” from their progenitor proto–neutron star (PNS), which is likely highly magnetized from an internal dynamo. We evaluate the conditions for the BH accretion disk to pin the PNS magnetosphere to its horizon immediately after the collapse. Our results show that the PNS spin-down energy released before collapse matches the kinetic energy of Type Ic-BL supernovae, while the nascent BH’s spin and magnetic flux produce jets consistent with observed GRB characteristics. We map our MESA models to 3D general-relativistic magnetohydrodynamic simulations and confirm that accretion disks confine the strong magnetic flux initiated near a rotating BH, enabling the launch of successful GRB jets, whereas a slower-spinning BH or one without a disk fails to do so.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142670346","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Probing the Origin of the Star Formation Excess Discovered by JWST through Gamma-Ray Bursts","authors":"Tatsuya Matsumoto, Yuichi Harikane, Keiichi Maeda and Kunihito Ioka","doi":"10.3847/2041-8213/ad8ce0","DOIUrl":"https://doi.org/10.3847/2041-8213/ad8ce0","url":null,"abstract":"The recent observations by the James Webb Space Telescope (JWST) have revealed a larger number of bright galaxies at z ≳ 10 than was expected. The origin of this excess is still under debate, although several possibilities have been presented. We propose that gamma-ray bursts (GRBs) are a powerful probe to explore the origin of the excess and, hence, the star and galaxy formation histories in the early universe. Focusing on the recently launched mission, Einstein Probe (EP), we find that EP can detect several GRBs annually at z ≳ 10, assuming the GRB formation rate calibrated by events at z ≲ 6 can be extrapolated. Interestingly, depending on the excess scenarios, the GRB event rate may also show an excess at z ≃ 10, and its detection will help to discriminate between the scenarios that are otherwise difficult to distinguish. Additionally, we discuss that the puzzling, red-color, compact galaxies discovered by JWST, the so-called “little red dots,” could host dark GRBs if they are dust-obscured star-forming galaxies. We are eager for unbiased follow-up of GRBs and encourage future missions such as HiZ-GUNDAM to explore the early universe.","PeriodicalId":501814,"journal":{"name":"The Astrophysical Journal Letters","volume":"99 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142671012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}