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Context: Current instrument developments at the largest telescopes worldwide have provisions for Multi-Conjugated Adaptive Optics (MCAO) modules. The large field of view and more uniform correction provided by these systems is not only…

Instrumentation and Methods for Astrophysics · Physics 2015-05-28 Eva Meyer , Martin Kuerster , Carmelo Arcidiacono , Roberto Ragazzoni , Hans-Walter Rix

Performances of an adaptive optics (AO) system are directly linked with the quality of its alignment. During the instrument calibration, having open loop fast tools with a large capture range are necessary to quickly assess the system…

Due to the demand for efficient fine-tuning of large language models, Low-Rank Adaptation (LoRA) has been widely adopted as one of the most effective parameter-efficient fine-tuning methods. Nevertheless, while LoRA improves efficiency,…

Computation and Language · Computer Science 2025-06-13 Naibin Gu , Zhenyu Zhang , Xiyu Liu , Peng Fu , Zheng Lin , Shuohuan Wang , Yu Sun , Hua Wu , Weiping Wang , Haifeng Wang

In the framework of a 4m class Solar Telescope we studied the performance of the MCAO using the LOST simulation package. In particular, in this work we focus on two different methods to reduce the time delay error which is particularly…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 Marco Stangalini , Francesco Berrilli , Dario Del Moro , Roberto Piazzesi

Multi-object adaptive optics (MOAO) has been demonstrated by the CANARY instrument on the William Herschel Telescope. However, for proposed MOAO systems on the next generation Extremely Large Telescopes, such as EAGLE, many challenges…

Instrumentation and Methods for Astrophysics · Physics 2015-06-16 A. G. Basden , N. A. Bharmal , R. M. Myers , S. L. Morris , T. J. Morris

All coronagraphic instruments for exoplanet high-contrast imaging need wavefront correction systems to reject optical aberrations and create sufficiently dark holes. Since the most efficient wavefront correction algorithms (controllers and…

Instrumentation and Methods for Astrophysics · Physics 2018-10-09 He Sun , N. Jeremy Kasdin , Robert Vanderbei

Studies of the human brain during natural activities, such as locomotion, would benefit from the ability to image deep brain structures during these activities. While Positron Emission Tomography (PET) can image these structures, the bulk…

Robotics · Computer Science 2023-11-30 Junxiang Wang , Iulian I. Iordachita , Peter Kazanzides

Beam lifetime in storage rings and colliders is affected by, among other effects, lattice nonlinearities. Their control are of great benefit to the dynamic aperture of an accelerator, whose enlargement leads in general to more efficient…

Accelerator Physics · Physics 2018-04-18 A. Franchi , L. Farvacque , F. Ewald , G. Le Bec , K. B. Scheidt

High-energy physics experiments rely on reconstruction of the trajectories of particles produced at the interaction point. This is a challenging task, especially in the high track multiplicity environment generated by p-p collisions at the…

Computer Vision and Pattern Recognition · Computer Science 2017-12-06 Maxim Borisyak , Andrey Ustyuzhanin , Denis Derkach , Mikhail Belous

We investigate methods to calibrate the non-common path aberrations at an adaptive optics system having a wavefront-correcting device working at an extremely high resolution (larger than 150x150). We use focal-plane images collected…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Visa Korkiakoski , Christoph U. Keller , Niek Doelman , Matthew Kenworthy , Gilles Otten , Michel Verhaegen

Nonlinear optics is a promising idea potentially opening the path towards achieving super high beam intensities in circular accelerators. Creation of a tune spread reaching 50% of the betatron tune would provide strong Landau damping and…

Accelerator Physics · Physics 2012-02-27 A. Valishev , S. Nagaitsev , V. Kashikhin , V. Danilov

Multi-objective Bayesian optimization (MOBO) provides a principled framework for optimizing expensive black-box functions with multiple objectives. However, existing MOBO methods often struggle with coverage, scalability with respect to the…

Machine Learning · Computer Science 2026-04-20 Yaohong Yang , Sammie Katt , Samuel Kaski

Whether is ground-based or space-based, any optical instrument suffers from some amount of optical geometric distortion. Recently, the diffraction-limited image quality afforded by space-based telescopes and by Adaptive Optics (AO)…

Instrumentation and Methods for Astrophysics · Physics 2017-11-29 A. Bernard , B. Neichel , L. M. Mugnier , T. Fusco

We propose and demonstrate a method for the adaptive wavefront correction of dynamic multimode fiber beams for the first time. The wavefront of incident beam is reconstructed in real-time based on the complete modal information, which…

Optical properties of components in a linac can be reconstructed from analysis of the orbit response matrix, composed from responses of BPMs to changes in currents of dipole correctors. An efficient way to record such response, discussed in…

Accelerator Physics · Physics 2021-09-27 Alexander Shemyakin

We present an analytical derivation of the on-axis performance of Adaptive Optics systems using a given number of guide stars of arbitrary altitude, distributed at arbitrary angular positions in the sky. The expressions of the residual…

Instrumentation and Methods for Astrophysics · Physics 2015-06-17 E. Tatulli , A. N. Ramaprakash

This paper introduces an Enhanced Boolean version of the Correlation Matrix Memory (CMM), which is useful to work with binary memories. A novel Boolean Orthonormalization Process (BOP) is presented to convert a non-orthonormal Boolean…

Neural and Evolutionary Computing · Computer Science 2016-07-15 Mario Mastriani

To calculate nonlinear transport of space charge dominated beam in 6D phase spaces, a computer code package LEADS-v5 (Linear and Electrostatic Accelerator Dynamics Simulations) has been developed. The codes calculate particle motions in the…

Accelerator Physics · Physics 2022-02-15 Jian-Qin Lu

Deep metric learning has been effectively used to learn distance metrics for different visual tasks like image retrieval, clustering, etc. In order to aid the training process, existing methods either use a hard mining strategy to extract…

Computer Vision and Pattern Recognition · Computer Science 2021-08-24 Bhavya Vasudeva , Puneesh Deora , Saumik Bhattacharya , Umapada Pal , Sukalpa Chanda

The primary objective of accelerator tuning is to correct its linear optics. This involves adjusting a large set of parameters, such as quadrupole lens gradients and alignment errors, as well as addressing various calibration errors in beam…

Accelerator Physics · Physics 2023-12-05 I. Morozov , Yu. Maltseva