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Related papers: Measure fiber position errors from spectra data

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We present a conceptual design for a fiber positioning system for multi-object high-resolution spectroscopy, designed to be compatible with the upcoming large telescopes with a wide field of view. The design incorporates multiple…

Instrumentation and Methods for Astrophysics · Physics 2025-09-23 Manjunath Bestha , T. Sivarani , Arun Surya , Sudharsan Yadav , Athira Unni , Parvathy M , Devika Divakar , S. Sriram , Ajin Prakash , Amirul Hasan

Optical quasar spectra can be used to trace variations of the fine-structure constant alpha. Controversial results that have been published in last years suggest that in addition to to wavelength calibration problems systematic errors might…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Nils Prause , Dieter Reimers

Understanding the dynamics of complex systems is a central task in many different areas ranging form biology via epidemics to economics and engineering. Unexpected behaviour of dynamic systems or even systems failure is sometimes difficult…

Optimization and Control · Mathematics 2020-06-11 Dominik Kahl , Andreas Weber , Maik Kschischo

Transmission matrix measurements of multimode fibers are now routinely performed in numerous labs, enabling control of the electric field at the distal end of the fiber and paving the way for the potential application to ultrathin medical…

In fiber optic sensing, time delays induced by polarization mode dispersion can distort signals in systems relying on phase or intensity variations for measurement, degrading performance, especially in long distance, high-precision…

Optics · Physics 2025-01-08 Wei-Qian Zhao , Zi-Fu Su , Ya-Fei Yu , Jin-Dong Wang

Focal Ratio Degradation (FRD) in fibres is a crucial factor to control in astronomical instruments in order to minimize light loss. As astronomical instrumentation has advanced, the integration of large populations of fibres has become…

Instrumentation and Methods for Astrophysics · Physics 2023-06-30 Weimin Sun , Xudong Chen , Jiabin Wang , Hang Jiang , Anzhi Wang , Qi Yan , Zhenyu Ma , Shengjia Wang , Tao Geng , Yue Zhong , Zhongquan Qu , Yunxiang Yan

Motivated by the recognition that variation in the optical transmission of the atmosphere is probably the main limitation to the precision of ground-based CCD measurements of celestial fluxes, we review the physical processes that attenuate…

Optimal error estimation is key to achieve accurate photometry and astrometry. Stellar fluxes and positions in high angular resolution images are typically measured with PSF fitting routines, such as StarFinder. However, the formal…

Instrumentation and Methods for Astrophysics · Physics 2022-08-12 E. Gallego-Cano , R. Schödel , A. T. Gallego-Calvente , A. M. Ghez

This paper presents the exact error analysis of point positioning equation used for airborne three-dimensional(3D) imaging sensor. With differential calculus and principles of precision analysis a mathematics formula on the point position…

Optics · Physics 2015-03-13 Yuesong Jiang , Xiaoxia Liu , Ruiqiang Chen , Yanling Wang

This paper addresses the problem of vision-based pedestrian localization, which estimates a pedestrian's location using images and camera parameters. In practice, however, calibrated camera parameters often deviate from the ground truth,…

Computer Vision and Pattern Recognition · Computer Science 2024-10-30 Wanyu Zhang , Jiaqi Zhang , Dongdong Ge , Yu Lin , Huiwen Yang , Huikang Liu , Yinyu Ye

Classical single-mode fiber interferometers, using one fiber per aperture, have very limited imaging capabilities and small field of view. Observations of extended sources (resolved by one aperture) cannot be fully corrected for wavefront…

Astrophysics · Physics 2009-11-07 Olivier Guyon

Precise localization is a core ability of an autonomous vehicle. It is a prerequisite for motion planning and execution. The well-established localization approaches such as Kalman and particle filters require a probabilistic observation…

Robotics · Computer Science 2020-03-02 Oleg Shipitko , Vladislav Kibalov , Maxim Abramov

Ground-based astronomy is unavoidably subject to the adverse effect of atmospheric turbulence, a.k.a. the seeing, which blurs the images and limits the achievable spatial resolution. For spectroscopic observations, it leads to slit or…

Instrumentation and Methods for Astrophysics · Physics 2024-06-12 Tobias M. Schmidt

Today's most precise optical instruments -- gravitational-wave interferometers and optical atomic clocks -- rely on long storage times for photons to realize their exquisite sensitivity. Optical fiber technology is the most widely deployed…

The precise determination of the position of point-like emitters and scatterers using far-field optical imaging techniques is of utmost importance for a wide range of applications in medicine, biology, astronomy, and physics. Although the…

Long-storage-time Fabry-Perot cavities are a core component of many precision measurement experiments. Optical loss in such cavities is a critical parameter in determining their performance; however, it is very difficult to determine a…

Optics · Physics 2013-11-28 T. Isogai , J. Miller , P. Kwee , L. Barsotti , M. Evans

The sky subtraction performances of multi-fiber spectrographs are discussed, analysing in detail the case of the OPTOPUS system at the 3.6 meter ESO telescope at La Silla. A standard technique, based on flat-fields obtained with a uniformly…

Astrophysics · Physics 2009-10-22 C. Lissandrini , S. Cristiani , F. La Franca

Single-exposure spectra in large spectral surveys are valuable for time domain studies such as stellar variability, but there is no available method to eliminate cosmic rays for single-exposure, multi-fiber spectral images. In this paper,…

Instrumentation and Methods for Astrophysics · Physics 2017-05-08 Zhongrui Bai , Haotong Zhang , Hailong Yuan , Jeffrey L. Carlin , Guangwei Li , Yongheng Zhao , Zihuang Cao

An optimal maximum-likelihood technique for computing point-source image centroids from many, slightly offset, CCD frames is presented. The method is especially useful for measuring stellar proper motions from data taken with the Wide Field…

Astrophysics · Physics 2015-06-24 Rodrigo Ibata , Geraint Lewis

Searches for variations of fundamental constants require accurate measurement errors. There are several potential sources of errors and quantifying each one accurately is essential. This paper addresses one source of uncertainty relating to…

Instrumentation and Methods for Astrophysics · Physics 2022-12-02 Chung-Chi Lee , John K. Webb , Darren Dougan , Vladimir A. Dzuba , Victor V. Flambaum