The Hubble Deep Field South (HDFS) has been recently selected and the observations are programmed for October 1998. We present the high resolution (FWHM ' 14 km s) spectrum of the quasar J2233–60 (zem ' 2.22) which is located 5.1 arcmin EAST of the HDFS. The NTT/EMMI spectrum redward of the Lyman–α emission line covers the spectral range 4386–8270 Å corresponding to redshift intervals for CIV a...

The GRANAT group (R. Sunyaev et al., Central Bureau of Astronomical Telegrams, International Astronomical Union, Circular No. 5481) recently reported the observation of a (545±11) keV line in the spectrum of the Crab Nebula. It is tempting to associate this with the positron-electron annihilation line at 511 keV. If this line originates from some transition at the surface of the neutron star in...

[1] Fundamental to the development of astronomical time scales is the recognition of oscillatory variability within stratigraphic data and its evaluation relative to a null “noise” hypothesis. In this study, Monte Carlo simulations are used to investigate the suitability of two commonly used noise hypotheses (the “conventional” and “robust” AR1 approaches), and the results highlight important l...

A major boost in the understanding of universe was given by revelation first coalescence event two neutron stars (GW170817) and observation same across entire electromagnetic spectrum. With third-generation gravitational wave detectors new astronomical facilities, we expect many multi-messenger events type. We anticipate need to analyse data provided us such not only fulfil requirements real-ti...

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 time-averages are recorded. An RFI ““ reference signal,ÏÏ is constructed from the cross power spectrum of the signals from the two polarizations of a reference horn...

Where appropriate repositories are not available to support all relevant astronomical data products, data can fall into darkness: unseen and unavailable for future reference and re-use. Some data in this category are legacy or old data, but newer datasets are also often uncurated and could remain dark. This paper provides a description of the design motivation and development of Astrolabe, a cy...

there are many different ways to subdivide the spectrum of a bounded linear operator; some of them aremotivated by applications to physics (in particular, quantum mechanics). in this study, the relationship betweenthe subdivisions of spectrum which are not required to be disjoint and goldberg's classification are given.moreover, these subdivisions for some summability methods are studied.

The Terahertz region of the electromagnetic spectrum which offers many molecular and atomic emission is of particular interest for astrophysics [1]. In order to explore the THz frequency band low noise heterodyne receiver are required. Hot electron bolometers (HEB) are the most sensitive THz mixers for frequencies above 1 THz offering a gain bandwidth (GBW) as wide as 4 GHz [2]. HEBs made from ...

Classical black holes are solutions of the field equations of General Relativity. Many astronomical observations suggest that black holes really exist in nature. However, an unambiguous proof for their existence is still lacking. Neither event horizon nor intrinsic curvature singularity have been observed by means of astronomical techniques. This paper introduces to particular features of black...

Over the last few years, an enormous amount of studies has been devoted to astronomical image restoration. The new challenge, nowadays, has been reported on the use of multichannel techniques to restore, segment and classify such images. The multichannel image segmentation problem, is a new field of great interest for the astronomical community. This paper presents an unsupervised method to aut...