Related papers: An X-ray photometry system I: Chandra ACIS
Galaxy clusters are massive dark matter-dominated systems filled with X-ray emitting, optically thin plasma. Their large size and relative simplicity (at least as astrophysical objects go) make them a unique laboratory to measure some of…
We use MARCS model atmosphere fluxes to compute synthetic colours, bolometric corrections and reddening coefficients for the Hipparcos/Tycho, Pan-STARRS1, SkyMapper and JWST systems. Tables and interpolation subroutines are provided to…
This article begins with the discussions on the formation of speckles in the case of non-coherent quasi monochromatic source and of ways to detect them. Prior to this, a brief introduction on the behavior of the atmosphere and its effect on…
Improving angular resolution is one of X-ray astronomy's big challenges. While X-ray interferometry should eventually vastly improve broad-band angular resolution, in the near-term, X-ray telescopes will sacrifice angular resolution for…
Gaia Data Release 3 provides novel flux-calibrated low-resolution spectrophotometry for about 220 million sources in the wavelength range 330nm - 1050nm (XP spectra). Synthetic photometry directly tied to a flux in physical units can be…
A hierarchy of statistics of increasing sophistication and accuracy is proposed, to exploit an interesting and fundamental arithmetic structure in the photon bunching noise of incoherent light of large photon occupation number, with the…
Motivated by their great potential to reduce the size, cost and weight, flat lenses, a category that includes diffractive lenses and metalenses, are rapidly emerging as key components with the potential to replace the traditional refractive…
On January 10 and 13, 2001, Venus was observed for the first time with an X-ray astronomy satellite. The observation, performed with the ACIS-I and LETG/ACIS-S instruments on Chandra, yielded data of high spatial, spectral, and temporal…
Surface chemistry of airless bodies in the solar system can be derived from remote x-ray spectral measurements from an orbiting spacecraft. X- rays from planetary surfaces are excited primarily by solar x-rays. Several experiments in the…
Nonlinear processes lie at the heart of many technologies such as frequency converters and entangled photon sources. Historically, observation and manipulation of these processes, for instance through nanostructures, has been limited to…
A software package able to simulate imaging observations of galaxy clusters by the Chandra X-ray telescope is here presented. We start from high resolution N-body hydrodynamical simulations of galaxy clusters and assign to each gas particle…
In this paper, we present the methodology of photometric redshift determination with the BATC 15-color system by using hyperz program. Both simulated galaxies and real galaxies with known redshifts were used to estimate the accuracy of…
We demonstrate a new kind of optical spectrometer employing photonic crystal patterns to outcouple waveguided light from a transparent substrate. This spectrometer consists of an array of photonic crystal patterns, nanofabricated in a…
The position accuracy of X-ray photons on a CCD detector is generally believed to be limited by the CCD pixel size. While this is true in general, the position accuracy for X-ray events which deposit charge in more than one pixel can be…
The observations of solar photosphere from the ground encounter significant problems due to the presence of Earth's turbulent atmosphere. Prior to applying image reconstruction techniques, the frames obtained in most favorable atmospheric…
We present a new method for photometering objects in galaxy clusters. We introduce a mode-filtering technique for removing spatially variable backgrounds, improving both detection and photometric accuracy (roughly halving the scatter in the…
We explore whether medium-resolution stellar spectra can be reconstructed from photometric observations, taking advantage of the highly compressible nature of the spectra. We formulate the spectral reconstruction as a least-squares problem…
Optical spectrometers have propelled scientific and technological advancements in a wide range of fields. While sophisticated systems with excellent performance metrics are serving well in controlled laboratory environments, many…
Most satellites decouple the acquisition of a panchromatic image at high spatial resolution from the acquisition of a multispectral image at lower spatial resolution. Pansharpening is a fusion technique used to increase the spatial…
We present a photometric method for identifying stars, galaxies and quasars in multi-color surveys, which uses a library of >65000 color templates. The method aims for extracting the information content of object colors in a statistically…