Related papers: Robust absolute solar flux density calibration for…
The development of new phased array systems in radio astronomy, as the low frequency array (LOFAR) and the square kilometre array (SKA), formed of a large number of small and flexible elementary antennas, has led to significant challenges.…
This paper provides an overview of the PACS photometer flux calibration concept, in particular for the principal observation mode, the scan map. The absolute flux calibration is tied to the photospheric models of five fiducial stellar…
We present the first observations of the Sun with the Allen Telescope Array (ATA). We used up to six frequencies, from 1.43 to 6 GHz, and baselines from 6 to 300 m. To our knowledge, these are the first simultaneous multifrequency full-Sun…
Observational cosmology employing optical surveys often require precise flux calibration. In this context we present SNIFS Calibration Apparatus (SCALA), a flux calibration system developed for the SuperNova Integral Field Spectrograph…
Polarimetric radio observations of the Sun can provide rich information about emission mechanisms and the propagation medium. For the past five decades, solar polarimetric studies at low radio frequencies have almost always assumed the…
Coronal magnetic fields are well known to be one of the crucial parameters defining coronal physics and space weather. However, measuring the global coronal magnetic fields remains challenging. The polarization properties of coronal radio…
We present the first dedicated observations of Interplanetary Scintillation (IPS) with the Murchison Widefield Array (MWA). We have developed a synthesis imaging technique, tailored to the properties of modern "large-N" low-frequency radio…
Continuum intensity observations obtained with the Michelson Doppler Imager (MDI) on-board the SoHO mission provide long time series of filtergrams that are ideal for studying the evolution of large-scale phenomena in the solar atmosphere…
We present the absolute flux and wavelength calibration of the James Webb Space Telescope (JWST) Near-Infrared Camera (NIRCam) Wide Field Slitless Spectroscopy (WFSS) mode. Each of NIRCam's two modules (A and B) provides independent long…
We present results from the first intensive monitoring campaign of a sample of Compact Symmetric Objects (CSOs). We observed seven CSOs at 8.5 GHz over a period of eight months, with an average spacing between observations of 2.7 days. Our…
Newly acquired data and improved data reduction algorithms mandate a fresh look at the absolute flux calibration of the CCD cameras on the Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS). The goals are to achieve a 1\%…
We have extended our previous work to use the Murchison Widefield Array (MWA) as a non-coherent passive radar system in the FM frequency band, using terrestrial FM transmitters to illuminate objects in Low Earth Orbit LEO) and the MWA as…
The Fourier transform spectrometer (FTS) is a core instrument for solar observation with high spectral resolution, especially in the infrared. The Infrared System for the Accurate Measurement of Solar Magnetic Field (AIMS), working at 10-13…
Context. Solar flux atlases observe the spatially integrated light from the Sun, treating it as a star. They are fundamental tools for gaining insight into the composition of the Sun and other stars, and are utilized as reference material…
We present deep polarimetric observations at 154 MHz with the Murchison Widefield Array (MWA), covering 625 deg^2 centered on RA=0 h, Dec=-27 deg. The sensitivity available in our deep observations allows an in-band, frequency-dependent…
Matter-wave interferometry with solids is highly susceptible to minute fluctuations of environmental fields, including gravitational effects from distant sources. Hence, experiments require a degree of shielding that is extraordinarily…
Solar radio emissions provide several unique diagnostics to estimate different physical parameters of the solar corona, which are otherwise simply inaccessible. However, imaging the highly dynamic solar coronal emissions spanning a large…
The inference of flows of material in the interior of the Sun is a subject of major interest in helioseismology. Here we apply techniques of Full Waveform Inversion (FWI) to synthetic data to test flow inversions. In this idealized setup,…
The Very Small Array (VSA) is a synthesis telescope designed to image faint structures in the cosmic microwave background on degree and sub-degree angular scales. The VSA has key differences from other CMB interferometers with the result…
The Atacama Large Millimeter/submillimeter Array (ALMA) allows for solar observations in the wavelength range of 0.3$-$10 mm, giving us a new view of the chromosphere. The measured brightness temperature at various frequencies can be fitted…