English
Related papers

Related papers: Correcting second-order contamination in low-resol…

200 papers

This paper presents a method for estimating the resolution of a digital holographic microscope using neural network analysis of reconstructed images. The spectral bandwidth of the source ($\Delta \lambda$) is used as a controlled image…

Optics · Physics 2026-05-12 A. G. Fedorov

We describe a device (adapter) for off-axis guiding and photometric calibration of wide-angle spectrographs operating in the prime focus of the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences. To…

Instrumentation and Methods for Astrophysics · Physics 2017-12-13 Victor L. Afanasiev , Vladimir R. Amirkhanyan , Alexei V. Moiseev , Roman I. Uklein , Alexander E. Perepelitsyn

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

We present a Hubble diagram of type II supernovae using corrected magnitudes derived only from photometry, with no input of spectral information. We use a data set from the Carnegie Supernovae Project I (CSP) for which optical and…

The detection of exoplanets in coronographic images is severely limited by residual starlight speckles. Dedicated post-processing can drastically reduce this "stellar leakage" and thereby increase the faintness of detectable exoplanets.…

Instrumentation and Methods for Astrophysics · Physics 2017-11-08 Nicholas Devaney , Éric Thiébaut

Spectral computed tomography has received considerable interest in recent years since spectral measurements contain much richer information about the object of interest. In spectral computed tomography, we are interested in the energy…

Numerical Analysis · Mathematics 2022-03-04 Katrine O Bangsgaard , Genoveva Burca , Evelina Ametova , Martin S Andersen , Jakob S Jørgensen

Radio astronomical observations have very poor signal to noise ratios, unlike in other disciplines. On the other hand, it is possible to observe the object of interest for long time intervals as well as using a wider bandwidth.…

Astrophysics · Physics 2008-09-02 Sarod Yatawatta

The growing level of radio frequency interference (RFI) is a recognized problem for research in radio astronomy. This paper describes an intuitive but powerful RFI cancellation technique that is suitable for radio spectroscopy where…

Astrophysics · Physics 2009-10-31 F. H. Briggs , J. F. Bell , M. J. Kesteven

Astronomical precision spectroscopy underpins searches for life beyond Earth, direct observation of the expanding Universe and constraining the potential variability of physical constants across cosmological scales. Laser frequency combs…

Astronomical images are of crucial importance for astronomers since they contain a lot of information about celestial bodies that can not be directly accessible. Most of the information available for the analysis of these objects starts…

Numerical Analysis · Mathematics 2019-04-10 Silvia Tozza , Maurizio Falcone

We discuss the extent to which photometric measurements alone can be used to identify Type Ia supernovae (SNIa) and to determine redshift and other parameters of interest for cosmological studies. We fit the light curve data of the type…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Yan Gong , Asantha Cooray , Xuelei Chen

Automated method of full spectrum fitting gives reliable estimates of stellar atmospheric parameters (Teff, logg and [Fe/H]) for late A, F, G and early K type stars. Recently, the technique was further improved in the cooler regime and the…

Solar and Stellar Astrophysics · Physics 2018-07-24 Kaushal Sharma , Santosh Joshi , H. P. Singh

Near-diffraction limited imaging and spectroscopy in the visible on large (8-10 meter) class telescopes has proved to be beyond the capabilities of current adaptive optics technologies, even when using laser guide stars. The need for high…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 Craig Mackay , Tim D. Staley , David King , Frank Suess , Keith Weller

Noise bias is a significant source of systematic error in weak gravitational lensing measurements that must be corrected to satisfy the stringent standards of modern imaging surveys in the era of precision cosmology. This paper reviews the…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-09 Xiangchong Li , Rachel Mandelbaum , The LSST Dark Energy Science Collaboration

Chemical imaging provides information about the distribution of chemicals within a target. When combined with structural information about the target, in situ chemical imaging opens the door to applications ranging from tissue…

Image and Video Processing · Electrical Eng. & Systems 2020-12-02 Luke Pfister , Rohit Bhargava , Yoram Bresler , P. Scott Carney

Recovering high-fidelity images of the night sky from blurred observations is a fundamental problem in astronomy, where traditional methods typically fall short. In ground-based astronomy, combining multiple exposures to enhance…

Instrumentation and Methods for Astrophysics · Physics 2025-09-04 Yashil Sukurdeep , Fausto Navarro , Tamás Budavári

We present a technique for the accurate estimation of large-scale errors in an antenna surface using astronomical sources and detectors. The technique requires several out-of-focus images of a compact source and the signal-to-noise ratio…

Astrophysics · Physics 2009-11-11 B. Nikolic , R. E. Hills , J. S. Richer

We present near-infrared (0.8-1.8 $\mu$m) spectra of 105 bright (${m_{J}}$ $<$ 10) stars observed with the low resolution spectrometer on the rocket-borne Cosmic Infrared Background Experiment (CIBER). As our observations are performed…

M.Levitin and E.Shargorodsky purposed in a recent article, [math.SP/0212087], the use of the so called ``second order relative spectrum'', to find eigenvalues of self-adjoint operators in gaps of the essential spectrum. Let $M$ be a…

Spectral Theory · Mathematics 2025-10-20 Lyonell Boulton

A next generation of space-based observatories aims to detect and characterize potentially Earth-like exoplanets around Sun-like stars using reflected light spectroscopy. However, it remains unclear how such direct imaging…

Earth and Planetary Astrophysics · Physics 2025-10-28 Arnaud Salvador , Tyler D. Robinson
‹ Prev 1 3 4 5 6 7 10 Next ›