1. RESEARCH INSTRUMENTATION AND NEEDS Astronomers using ground-based telescopes are necessarily engaged in negating the effects of the earth’s atmosphere, which acts as a wavelength dependent, spatially and temporally non-stationary refractive optical element in any ground based telescope system. Almost all of the extinction of starlight due to aerosols happens in the troposphere. These troposp...

We report the first observations of an astronomical object using a superconducting tunnel junction (STJ) device, a pixel detector with intrinsic energy resolution in the optical wavelength range. The Crab pulsar was observed using a 6 × 6 array of Tantalum STJs at the 4.2-m William Herschel Telescope on La Palma. Each array element provides photon counting capability recording up to ∼ 10 3 phot...

Images secured from an astronomical telescope usually suffer from blur and from interference that scientists refer to as ‘‘noise’’. Therefore, good image restoration technique has become an important tool in astronomical observation. In this paper, we propose a modified anisotropic diffusion scheme to tackle the problem of image restoration in astronomy, especially in the case of nebula images....

The FITS is the standard file format in astronomy, and it has been extended to agree with astronomical needs of the day. However, astronomical datasets have been inflating year by year. In case of ALMA telescope, a ∼ TB scale 4-dimensional data cube may be produced for one target. Considering that typical Internet bandwidth is a few 10 MB/s at most, the original data cubes in FITS format are ho...

Your thesaurus codes are: 03(03.09.2) Abstract. We report first white-light interferograms obtained with an integrated optics beam combiner on a glass plate. These results demonstrate the feasability of single-mode interferometric beam combination with integrated optics technology presented and discussed in paper I (Malbet et al. 1999). The demonstration is achieved in laboratory with off-the-s...

The pyramid wave-front sensor in its original form works with a mechanical modulation that adapts the linear range of the sensor to seeing and sensing conditions. For adaptive optics systems working in an astronomical context, the way in which the aberrations produced by the atmospheric turbulence, which are not seen by the sensor owing to its limited temporal bandwidth, act as modulators is sh...

As a follow-up of the X–ray serendipitous detection of the source 2MASX J14585116−1652223, medium-resolution optical spectroscopic observations collected at the 1.5-metre “Cassini” telescope of the Astronomical Observatory of Bologna were performed. This allowed us to determine the extragalactic nature of this X–ray source, which is a Type 2 Seyfert galaxy at redshift z = 0.068 ± 0.001. This re...

The caustic or Gaviola test, used for testing aspheric mirrors, has been studied with reference to the research of Schroader ["The caustic test," in Amateur Telescope Making III, A. G. Ingalls, ed. (Kingsport Press, Kingsport, Tenn., 1953), pp. 429-456]. It is shown that the two central formulas, which are used to determine the mirror quality, give significant errors for the large-diameter, sho...

We propose a new probe of the dependence of the fine-structure constant α on a strong gravitational field using metal lines in the spectra of white-dwarf stars. Comparison of laboratory spectra with far-UV astronomical spectra from the white-dwarf star G191-B2B recorded by the Hubble Space Telescope Imaging Spectrograph gives limits of Δα/α=(4.2±1.6)×10(-5) and (-6.1±5.8)×10(-5) from FeV and Ni...

We present a summary of optical/NIR deep surveys for very high-z galaxies using the 8.2m Subaru Telescope operated by National Astronomical Observatory of Japan. The prime focus mosaic CCD camera, Suprime-Cam, with a very wide field of view, 34′ × 27′, allows us to carry out efficient optical deep surveys. In particular, the Subaru Deep Field project has provided us a number of Lymanα emitters ...