Results 1 to 10 of about 5,796,492 (306)

Optimizing Structural Parameters and Layout of Fiber Positioners with the Whale Optimization Algorithm for LAMOST

The Astronomical Journal
Robotic fiber positioner (RFP) arrays are essential for multiobject spectroscopic telescopes. To improve the survey efficiency, they are densely arranged on the focal planes with overlapped patrol areas, guaranteeing full coverage and increasing the ...
Zengxiang Zhou, Jiahao Zhou, Baolong Chen, Jianping Wang, Zhigang Liu, Hongzhuan Hu, Feifan Zhang   +6 more
doaj   +1 more source

Primary beam calibration for commensal telescopes utilizing offset optics

Frontiers in Astronomy and Space Sciences
IntroductionAccurate primary beam calibration is essential for precise brightness measurements in radio astronomy. The VLA Low-band Ionosphere and Transient Experiment (VLITE) faces challenges in calibration due to the offset Cassegrain optics used in ...
Emil Polisensky, Tracy E. Clarke, Simona Giacintucci, Wendy Peters   +3 more
doaj   +1 more source

Bayesian Doppler Imaging: Simultaneous Inference of Surface Maps and Geometric Parameters

The Astrophysical Journal
We present a fully Bayesian, pixel-based Doppler imaging framework that enables the simultaneous inference of surface brightness maps and geometric parameters, including the inclination i and equatorial rotation velocity v _rot , from high-resolution ...
Yamato Ureshino, Hajime Kawahara, Hibiki Yama, Kento Masuda   +3 more
doaj   +1 more source

Empirical modeling of tropospheric delays with uncertainty [PDF]

Geoscientific Model Development
Accurate modeling of tropospheric delay is important for high-precision data analysis of space geodetic techniques, such as the Global Navigation Satellite System (GNSS).
J. Wang, J. Wang, J. Wang, J. Chen, J. Chen, J. Chen, Y. Zhang   +6 more
doaj   +1 more source

Astronomia ex machina: a history, primer and outlook on neural networks in astronomy

Royal Society Open Science, 2023
In this review, we explore the historical development and future prospects of artificial intelligence (AI) and deep learning in astronomy. We trace the evolution of connectionism in astronomy through its three waves, from the early use of multilayer ...
Michael J. Smith, James E. Geach
doaj   +1 more source

A Hierarchical Point-spread Function Reconstruction Method

The Astrophysical Journal
Reconstruction of the point-spread function (PSF) plays an important role in many areas of astronomy, including photometry, astrometry, galaxy morphology, and shear measurement.
Pedro Alonso, Jun Zhang, Cong Liu
doaj   +1 more source

The Digitization of Photographic Spectra in the Dominion Astrophysical Observatory Plate Collection with Commercial Scanners: A Pilot Study

The Astronomical Journal
Commercial flatbed scanners have the potential to deliver a quick and efficient means of capturing the scientific content of spectra recorded on photographic plates.
T. J. Davidge
doaj   +1 more source

Projected Rotational Velocities for LAMOST Stars with Effective Temperatures Lower than 9000 K

The Astrophysical Journal Supplement Series
In Data Release 9 of LAMOST, we present measurements of v sin i for a total of 121,698 stars measured using the Medium Resolution Spectrograph (MRS) and 80,108 stars using the Low Resolution Spectrograph (LRS).
Fang Zuo, A-Li Luo, Bing Du, Yinbi Li, Hugh R. A. Jones, Yi-han Song, Xiao Kong, Yan-xin Guo   +7 more
doaj   +1 more source

Singular spectrum analysis for the time-variable seasonal signals from GPS in Yunnan Province

Geodesy and Geodynamics
Studying the seasonal deformation in GPS time series is important to interpreting geophysical contributors and identifying unmodeled and mismodeled seasonal signals.
Weijie Tan, Junping Chen, Yize Zhang, Bin Wang, Songyun Wang   +4 more
doaj   +1 more source

Single-pulse Correlations in PSR B0329+54: Implications for Radio Emission Zones

The Astrophysical Journal
Individual radio pulses from a pulsar are directly linked to the underlying emission processes and the associated magnetic field geometry within its magnetosphere.
Shyam S. Sharma, Tetsuya Hashimoto, Tomotsugu Goto, Sanjay Kudale, Sujin Eie, Simon C.-C. Ho   +5 more
doaj   +1 more source