English
Related papers

Related papers: Positioning errors and efficiency in fiber spectro…

200 papers

The frequency dependent beampatterns of an active sonar projector filters the acoustic signal that is transmitted into the medium, also known as the transmit waveform. This filtering encodes information about the target's bearing relative…

Signal Processing · Electrical Eng. & Systems 2021-07-28 David A. Hague , Matthew D. Tidwell

In the next years, several cosmological surveys will rely on imaging data to estimate the redshift of galaxies, using traditional filter systems with 4-5 optical broad bands; narrower filters improve the spectral resolution, but strongly…

We present a new fiber assignment algorithm for a robotic fiber positioner system in multi-object spectroscopy. Modern fiber positioner systems typically have overlapping patrol regions, resulting in the number of observable targets being…

With millimeter wave wireless communications, the resulting radiation reflects on most visible objects, creating rich multipath environments, namely in urban scenarios. The radiation captured by a listening device is thus shaped by the…

Signal Processing · Electrical Eng. & Systems 2018-04-12 João Gante , Gabriel Falcão , Leonel Sousa

Shack-Hartmann wavefront sensors using wound fibre bundles are desired for multi-object adaptive optical systems to provide large multiplex positioned by Starbugs. The use of the large-sized wound fibre bundle provides the exibility to use…

Instrumentation and Methods for Astrophysics · Physics 2018-04-11 Jessica R. Zheng , Michael Goodwin , Jon Lawrence

Optical interferometers provide multiple wavelength measurements. In order to fully exploit the spectral and spatial resolution of these instruments, new algorithms for image reconstruction have to be developed. Early attempts to deal with…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 Éric Thiébaut , Ferréol Soulez , Loïc Denis

Optical fiber modal noise is a limiting factor for high precision spectroscopy signal-to-noise in the near-infrared and visible. Unabated, especially when using highly coherent light sources for wavelength calibration, modal noise can…

Instrumentation and Methods for Astrophysics · Physics 2018-02-21 Ryan R. Petersburg , Tyler M. McCracken , Dominic Eggerman , Colby A. Jurgenson , David Sawyer , Andrew E. Szymkowiak , Debra A. Fischer

Self-calibrating and dual-slope measurements have been used in the field of diffuse optics for robust assessment of absolute values or temporal changes in the optical properties of highly scattering media and biological tissue. These…

Optics · Physics 2025-05-05 Giles Blaney , Angelo Sassaroli , Tapan Das , Sergio Fantini

In fiber-fed galaxy redshift surveys, the finite size of the fiber plugs prevents two fibers from being placed too close to one another, limiting the ability of studying galaxy clustering on all scales. We present a new method for…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-07 Hong Guo , Idit Zehavi , Zheng Zheng

Efficient fiber-to-chip coupling has been a major hurdle to cost-effective packaging and scalable interconnections of photonic integrated circuits. Conventional photonic packaging methods relying on edge or grating coupling are constrained…

Redshift space distortions privilege the location of the observer in cosmological redshift surveys, breaking the translational symmetry of the underlying theory. This violation of statistical homogeneity has consequences for the modeling of…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-23 Emanuele Castorina , Martin White

Many astrophysical analyses depend on estimates of redshifts (a proxy for distance) determined from photometric (i.e., imaging) data alone. Inaccurate estimates of photometric redshift uncertainties can result in large systematic errors.…

Instrumentation and Methods for Astrophysics · Physics 2022-05-31 Biprateep Dey , Jeffrey A. Newman , Brett H. Andrews , Rafael Izbicki , Ann B. Lee , David Zhao , Markus Michael Rau , Alex I. Malz

Plastic scintillation detectors are increasingly used to measure dose distributions in the context of radiotherapy treatments. Their water-equivalence, real-time response and high spatial resolution distinguish them from traditional…

Medical Physics · Physics 2021-09-22 Emily Cloutier , Louis Archambault , Luc Beaulieu

In photo injectors, the transverse emittance is one of the key measures of beam quality as it defines the possible performance of the whole facility. As such it is important to measure the emittance in photo injectors and ensure the…

Analyzing the internal loss characteristics and multimodedness of (integrated) optical devices can prove difficult. One technique to recover this information is to Fourier transform the transmission spectrum of optical components. This…

Image transmission through multimode optical fibers has been an area of immense interests driven by the demand for miniature endoscopes in biomedicine and higher speed and capacity in telecommunications. Conventionally, a complex-valued…

Optics · Physics 2020-07-15 Tianrui Zhao , Sebastien Ourselin , Tom Vercauteren , Wenfeng Xia

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

In this paper, we report all results obtained with a fiber scrambler on the Hamilton spectrograph at Lick Observatory. We demonstrate an improvement in the stability of the instrumental profile using this fiber scrambler. Additionally, we…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 Julien F. P. Spronck , Debra A. Fischer , Zachary A. Kaplan , Christian Schwab , Andrew Szymkowiak

The perception of the blur due to accommodation failures, insufficient optical correction or imperfect image reproduction is a common source of visual discomfort, usually attributed to an anomalous and annoying distribution of the image…

Image and Video Processing · Electrical Eng. & Systems 2020-11-16 Elio D. Di Claudio , Paolo Giannitrapani , Giovanni Jacovitti

We examine the impact of fiber assignment on the measurement of galaxy clustering and its cross correlation with weak lensing fields. Unlike the past spectroscopic galaxy surveys such as Baryon Oscillation Spectroscopic Survey (BOSS),…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-16 Ryu Makiya , Tomomi Sunayama
‹ Prev 1 4 5 6 7 8 10 Next ›