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Achieving GPT-4o level performance in astronomy with a specialized 8B-parameter large language model [PDF]
Scientific ReportsAstroSage-Llama-3.1-8B is a domain-specialized natural-language AI assistant tailored for research in astronomy, astrophysics, cosmology, and astronomical instrumentation.
Tijmen de Haan +8 more
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Calibration of the Timing Performance of GECAM-C
The Astrophysical Journal Supplement Series, 2023 As a new member of the Gravitational-wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) after GECAM-A and GECAM-B, GECAM-C (originally called HEBS), which was launched on board the SATech-01 satellite on 2022 July 27, aims to monitor ...
Shuo Xiao +37 more
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Astronomical Optical Interferometry. I. Methods and Instrumentation [PDF]
Serbian Astronomical Journal, 2010 Previous decade has seen an achievement of large interferometricprojects including 8-10m telescopes and 100m class baselines. Modern computerand control technology has enabled the interferometric combination of lightfrom separate telescopes also in the ...
Jankov, S.
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Dispersion Characteristics of the Multi-mode Fiber-fed VIPA Spectrograph
The Astronomical Journal, 2023 A high-resolution ( ${ \mathcal R }\gt {10}^{5}$ ), multi-mode fiber-fed spectrograph on large telescopes with a reasonable size is desirable in astronomy.
Xiaoming Zhu +4 more
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Real-time Experimental Demonstrations of a Photonic Lantern Wave-front Sensor
The Astrophysical Journal Letters, 2023 The direct imaging of an Earth-like exoplanet will require sub-nanometric wave-front control across large light-collecting apertures to reject host starlight and detect the faint planetary signal.
Jonathan W. Lin +14 more
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A Two-element Interferometer for Millimeter-wave Solar Flare Observations
The Astrophysical Journal Supplement Series, 2023 In this paper, we present the design and implementation of a two-element interferometer operating in the millimeter-wave band (39.5–40 GHz) for observing solar radio emissions through nulling interference.
YongLin Yu +10 more
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First Constraints on Helium +He3 Evolution in z = 3–4 Using the 8.67 GHz Hyperfine Transition
The Astrophysical Journal, 2023 We present the first constraints on the cross-correlation power spectrum of the He ii ( ^+ He ^3 ) signal strength using the redshifted 8.67 GHz hyperfine transition between z = 2.9 and 4.1 and with interferometric data obtained from the public archive ...
Cathryn M. Trott, Randall B. Wayth
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The Simons Observatory: Rotation Performance of Cryogenic Half-wave Plate Polarization Modulators
The Astrophysical Journal Supplement SeriesWe present the on-site rotation performance of the first three cryogenic continuously rotating half-wave plate (HWP) polarization modulators for the Simons Observatory small aperture telescopes (SATs).
Kyohei Yamada +12 more
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The Astronomical JournalThe Large Sky Area Multi-Object Fiber Spectroscopy Telescope (LAMOST) is one of the most effective multiobject spectroscopic instruments. Its survey efficiency is guaranteed by simultaneously positioning multiple fibers via 4000 robotic fiber positioners
Feifan Zhang +5 more
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The Calibration of theta-phi Fiber Positioners Based on the Differential Evolution Algorithm
The Astronomical JournalRobotic fiber positioner (RFP) arrays are commonly adopted in multiobject spectroscopic instruments. The positioning accuracy is a common but vital issue for RFP as inaccurate fiber placement may heavily affect the observation performance.
Feifan Zhang +6 more
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