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At frequencies close to 1 GHz the sky diffuse radiation is a superposition of radiation of Galactic origin, the 3 K Relic or Cosmic Microwave Background Radiation, and the signal produced by unresolved extragalactic sources. Because of their different origin and space distribution the relative importance of the three components varies with frequency and depends on the direction of observation. With the aim of disentangling the components we built TRIS, a system of three radiometers, and studied the temperature of the sky at $ u =0.6$, $ u = 0.82$ and $ u = 2.5$ GHz using geometrically scaled antennas with identical beams (HPBW = $18^{circ} times 23^{circ}$). Observations included drift scans along a circle at constant declination $delta=+42^{circ}$ which provided the dependence of the sky signal on the Right Ascension, and absolute measurement of the sky temperature at selected points along the same scan circle. TRIS was installed at Campo Imperatore (lat. = $42^{circ}~26$ N, long.= $13^{circ}~33$, elevation = 2000 m a.s.l.) in Central Italy, close to the Gran Sasso Laboratory.
With the TRIS experiment we have performed absolute measurements of the sky brightness in a sky circle at $delta = +42^{circ}$ at the frequencies $ u =$ 0.60, 0.82 and 2.5 GHz. In this paper we discuss the techniques used to separate the different co
We apply the sky brightness modelling technique introduced and developed by Roy Garstang to high-resolution DMSP-OLS satellite measurements of upward artificial light flux and to GTOPO30 digital elevation data in order to predict the brightness distr
This paper presents optical night sky brightness measurements from the stratosphere using CCD images taken with the Super-pressure Balloon-borne Imaging Telescope (SuperBIT). The data used for estimating the backgrounds were obtained during three com
Site-testing is crucial for achieving the goal of scientific research and analysis of meteorological and optical observing conditions is one of the basic tasks of it. As one of three potential sites to host 12-meter Large Optical/infrared Telescope (
The ARCADE 2 instrument has measured the absolute temperature of the sky at frequencies 3, 8, 10, 30, and 90 GHz, using an open-aperture cryogenic instrument observing at balloon altitudes with no emissive windows between the beam-forming optics and