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We present the first on-sky results of the micro-lens ring tip-tilt (MLR-TT) sensor. This sensor utilizes a 3D printed micro-lens ring feeding six multi-mode fibers to sense misaligned light, allowing centroid reconstruction. A tip-tilt…

Atmospheric Cherenkov telescopes rely on the Earth's atmosphere as part of the detector. The presence of clouds affects observations and can introduce biases if not corrected for. Correction methods typically require an atmospheric profile,…

Instrumentation and Methods for Astrophysics · Physics 2024-04-03 Julian Sitarek , Mario Pecimotika , Natalia Żywucka , Dorota Sobczyńska , Abelardo Moralejo , Dario Hrupec

Two major challenges of 3D LiDAR Panoptic Segmentation (PS) are that point clouds of an object are surface-aggregated and thus hard to model the long-range dependency especially for large instances, and that objects are too close to…

Computer Vision and Pattern Recognition · Computer Science 2022-01-19 Shuangjie Xu , Rui Wan , Maosheng Ye , Xiaoyi Zou , Tongyi Cao

From the South Pole, microthermal turbulence within a narrow surface boundary layer some 200m thick provides the dominant contribution to the astronomical seeing. We present results for the seeing at a wavelength of 2.4um. The narrow…

Astrophysics · Physics 2009-11-07 RD Marks

In scanning probe microscopy laser interferometers are usually used for measuring the position of the probe tip with a metrological traceability. As the most of the AFM setups are designed to work under standard atmospheric conditions the…

Instrumentation and Detectors · Physics 2022-10-25 V. Hucl , M. Cizek , J. Hrabina , B. Mikel , S. Rerucha , Z. Buchta , P. Jedlicka , A. Lesundak , J. Oulehla , L. Mrna , M. Sarbort , R. Smid , J. Lazar , O. Cip

Atmospheric retrieval studies are essential to determine the science requirements for future generation missions, such as the Large Interferometer for Exoplanets (LIFE). The use of heterogeneous absorption cross-sections might be the cause…

This paper introduces five new density and accuracy metrics for aerial point clouds that address the complexity and objectives of modern, dense laser scans of urban scenes. The five metrics describe (1) vertical surface density (points per…

Signal Processing · Electrical Eng. & Systems 2020-12-18 Michael H. Stanley , Debra F. Laefer

Astronomical seeing is quantified by a single parameter, turbulence integral, in the framework of the Kolmogorov turbulence model. This parameter can be routinely measured by a Differential Image Motion Monitor, DIMM. A new instrument,…

Astrophysics · Physics 2009-11-13 A. Tokovinin , V. Kornilov

Long-term orbital evolution of multi-planet systems under tidal dissipation often converges to a stationary state, known as the tidal fixed point. The fixed point is characterized by a lack of oscillations in the eccentricities and apsidal…

Earth and Planetary Astrophysics · Physics 2015-05-27 Konstantin Batygin , Gregory Laughlin

We present an approach for state and parameter estimation in retinal laser treatment by a novel setup where both measurement and heating is performed by a single laser. In this medical application, the temperature that is induced by the…

Systems and Control · Electrical Eng. & Systems 2021-03-05 Viktoria Kleyman , Manuel Schaller , Mitsuru Wilson , Mario Mordmüller , Ralf Brinkmann , Karl Worthmann , Matthias A. Müller

CONTEXT: Spectral-line asymmetries and wavelength shifts are signatures of hydrodynamics in solar and stellar atmospheres. Theory may precisely predict idealized lines, but observed spectra are limited by blends, too few suitable lines,…

Astrophysics · Physics 2009-11-13 Dainis Dravins

Line asymmetries and shifts are a powerful tool for studying velocity fields in the stellar photospheres. Other effects, however, could also generate asymmetries blurring the information of the velocity patterns. We have studied the shifts…

Astrophysics · Physics 2009-10-30 C. Allende Prieto , R. J. Garcia Lopez , J. Trujillo Bueno

Spatial phase-referencing in dual-field optical interferometry is reconsidered. Our analysis is based on the 2-sample variance of the differential phase between target and reference star. We show that averaging over time of the atmospheric…

Astrophysics · Physics 2009-11-07 Gerard Daigne , Jean-Francois Lestrade

Intensity mapping with the redshifted 21-cm line is an emerging tool in cosmology. Drift scan observations, where the antennas are fixed to the ground and the telescope's pointing center (PC) changes continuously on the sky due to earth's…

Instrumentation and Methods for Astrophysics · Physics 2022-12-14 Suman Chatterjee , Somnath Bharadwaj , Samir Choudhuri , Shiv Sethi , Akash Kumar Patwa

The characterisation of exoplanets is critical to understanding planet diversity and formation, their atmospheric composition and the potential for life. This endeavour is greatly enhanced when light from the planet can be spatially…

Lidar point cloud distortion from moving object is an important problem in autonomous driving, and recently becomes even more demanding with the emerging of newer lidars, which feature back-and-forth scanning patterns. Accurately estimating…

Robotics · Computer Science 2022-07-05 Wen Yang , Zheng Gong , Baifu Huang , Xiaoping Hong

We forecast the detectability of the lensing footprint of a collapsing cosmic texture, a topological defect proposed as an explanation of the CMB Cold Spot. Our pipeline is a quadratic, template-amplitude estimator for localized,…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-08 Pedro da Silveira Ferreira , Stephen Owusu

Precise astrometric and photometric measurements of celestial point sources are fundamental to modern astronomy. These measurements, used to determine object positions, motions, and fluxes, are based on observational models that have…

Instrumentation and Methods for Astrophysics · Physics 2025-12-05 Sebastián Espinosa , Rene A. Mendez , Jorge F. Silva , Marcos Orchard

In this tutorial we summarize the physics and mathematics behind refractive electromagnetic wave bending and delay. Refractive bending and delay through the Earth's atmosphere at both radio/millimetric and optical/IR wavelengths are…

Instrumentation and Methods for Astrophysics · Physics 2015-06-23 Jeffrey G. Mangum , Patrick Wallace

LiDAR-based 3D object detection plays a crucial role in modern autonomous driving systems. LiDAR data often exhibit severe changes in properties across different observation ranges. In this paper, we explore cross-range adaptation for 3D…

Computer Vision and Pattern Recognition · Computer Science 2019-09-27 Ze Wang , Sihao Ding , Ying Li , Minming Zhao , Sohini Roychowdhury , Andreas Wallin , Guillermo Sapiro , Qiang Qiu