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A set of co-aligned high resolution images from the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory (SDO) is used to investigate propagating disturbances (PDs) in warm fan loops at the periphery of a non-flaring…

Solar and Stellar Astrophysics · Physics 2015-06-17 Vadim M. Uritsky , Joseph M. Davila , Nicholeen M. Viall , Leon Ofman

Achieving sub-arcsecond co-registration across varying time-lines of multi-wavelength and instrument images is not trivial, and requires accurate characterization of instrument pointing jitter. In this work we have investigated internal…

Solar and Stellar Astrophysics · Physics 2015-01-22 N. Brice Orange , Hakeem M. Oluseyi , David L. Chesny , Maulik Patel , Patrick Champey , Katie Hesterly , Dylan Anthony , Robert Treen

When inverting solar spectra, image degradation effects that are present in the data are usually approximated or not considered. We develop a data reduction method that takes these issues into account and minimizes the resulting errors. By…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 M. van Noort

Intermediate Scattering Functions (ISF's) are measured for colloidal hard sphere systems using both Dynamic Light Scattering (DLS) and X-ray Photon Correlation Spectroscopy (XPCS). We compare the techniques, and discuss the advantages and…

Soft Condensed Matter · Physics 2015-05-19 V. A. Martinez , J. H. J Thijssen , F. Zontone , W. van Megen , G. Bryant

We describe the observing simulation software FISVI (FIS Virtual Instrument), which was developed for the Far-Infrared Surveyor (FIS) that will be on the Japanese infrared astronomy mission ASTRO-F. The FISVI has two purposes: one is to…

We consider the best today available observations of the Sun free of turbulent Earth atmospheric effects, taken with the Solar Optical Telescope (SOT) onboard the Hinode spacecraft. Both the instrumental smearing and the observed stray…

Solar and Stellar Astrophysics · Physics 2015-06-30 Hadis Goodarzi , Serge Koutchmy , Ali Adjabshirizadeh

Most current astronomical adaptive optics (AO) systems rely on the availability of a bright star to measure the distortion of the incoming wavefront. Replacing the guide star with an artificial laser beacon alleviates this dependency on…

Astrophysics · Physics 2009-11-11 E. Steinbring , S. M. Faber , B. A. Macintosh , D. Gavel , E. L. Gates

Modeling the brightness of satellites in large Low-Earth Orbit (LEO) constellations can not only assist the astronomical community in assessing the impact of reflected light from satellites, optimizing observing schedules and guiding data…

Instrumentation and Methods for Astrophysics · Physics 2024-05-16 Yao Lu

We investigate the effects of atmospheric dispersion on observations of the Sun at the ever-higher spatial resolutions afforded by increased apertures and improved techniques. The problems induced by atmospheric refraction are particularly…

Astrophysics · Physics 2008-11-26 Kevin P. Reardon

The EUV Imaging Spectrometer (EIS) on the Hinode satellite is capable of measuring emission line center positions for Gaussian line profiles to a fraction of a spectral pixel, resulting in relative solar Doppler-shift measurements with an…

Photometric surveys require precise point spread function (PSF) characterization, as it varies across filters and is crucial for accurate photometry and low surface brightness (LSB) studies. However, the small PSF size provided by default…

The weak gravitational lensing is a powerful tool in modern cosmology. To accurately measure the weak lensing signal, one has to control the systematic bias to a small level. One of the most difficult problems is how to correct the smearing…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-28 Q. Y. Liu , X. Z. Er , Z. H. Fan , D. Z. Liu , G. L. Li , C. L. Wei , Z. Ban , X. B. Li , D. Yue

Reconstruction of the point spread function (PSF) is a critical process in weak lensing measurement. We develop a real-data based and galaxy-oriented pipeline to compare the performances of various PSF reconstruction schemes. Making use of…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-24 Tianhuan Lu , Jun Zhang , Fuyu Dong , Yingke Li , Dezi Liu , Liping Fu , Guoliang Li , Zuhui Fan

We investigate the impact of point spread function (PSF) fitting errors on cosmic shear measurements using the concepts of complexity and sparsity. Complexity, introduced in a previous paper, characterizes the number of degrees of freedom…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 S. Paulin-Henriksson , A. Refregier , A. Amara

Context: ASPIICS is a giant-baseline visible light solar coronagraph, which relies on the millimetric positioning performance of the precision formation flying Proba-3 mission of the European Space Agency. Proba-3 was launched on 5 Dec…

Instrumentation and Methods for Astrophysics · Physics 2026-04-24 S. Shestov , A. N. Zhukov , R. Rougeot , C. Aime , B. Bourgoignie , L. Dolla , N. Britavskiy , S. Fineschi , S. Gunar , P. Lamy , M. Mierla , H. Peter , P. Rudawy , K. Tsinganos

Synthetic aperture sonar (SAS) image resolution is constrained by waveform bandwidth and array geometry. Specifically, the waveform bandwidth determines a point spread function (PSF) that blurs the locations of point scatterers in the…

Computer Vision and Pattern Recognition · Computer Science 2021-12-17 Albert Reed , Thomas Blanford , Daniel C. Brown , Suren Jayasuriya

We demonstrate that artificial bipolar structure can be detected using spectro-astrometry when the point spread function (PSF) of a point source suffers distortion in a relatively wide slit. Spectro-astrometry is a technique which allows us…

Astrophysics · Physics 2009-11-13 E. Brannigan , M. Takami , A. Chrysostomou , J. Bailey

The InfraRed Imaging Spectrograph (IRIS) is a first-light instrument for the Thirty Meter Telescope (TMT) that will be used to sample the corrected adaptive optics field by the Narrow-Field Infrared Adaptive Optics System (NFIRAOS) with a…

Solar activity plays a quintessential role in influencing the interplanetary medium and space-weather around the Earth. Remote sensing instruments onboard heliophysics space missions provide a pool of information about the Sun's activity…

Current and future imaging surveys will measure cosmic shear with statistical precision that demands a deeper understanding of potential systematic biases in galaxy shape measurements than has been achieved to date. We use analytic and…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-15 Joshua E. Meyers , Patricia R. Burchat
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