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COCHISE is a 2.6 meter millimetric telescope, mainly devoted to cosmological observations, located at Concordia. In this paper we report on the installation phases and preliminary operations performed with this instrument. At present, COCHISE is the largest telescope located at Concordia, for that reason it represents a pathfinder for future telescopes.

COMPASS is an on-axis 2.6 meter telescope coupled to a correlation polarimeter operating at a wavelength of 1 cm. The entire instrument was built specifically for CMB polarization studies. We report here on observations of February 2001 - April 2001 using this system. We set an upper limit on E-mode polarized anisotropies of 33.5 uK (95% confidence limit) in the l-range 200-600.

Published in: Astrophys. J. 513 (1999) 23 citations recorded in [Science Citation Index] Abstract: We report simultaneous observations at 1.2 and 2 mm, with a double channel photometer on the SEST Telescope, of the X-ray cluster RXJ0658-5557 in search for the Sunyaev-Zel'dovich (S-Z). The S-Z data were analyzed using the relativistically correct expression for the Comptonization parameter and we find from the detected decrement (2.60 +/- 0.79) ~ 10^{-4}, which is consistent with that computed using the X-ray (ROSAT and ASCA) observations. The uncertainty includes contributions due to statistical uncertainty in the detection and systematics and calibration. The 1.2 {mm} channel data alone gives rise to a larger Comptonization parameter and this result is discussed in terms of contamination from foreground sources and/or dust in the cluster or from a possible systematic effect. We then make use of the combined analysis of the ROSAT and ASCA X-ray satellite observations to determine an isothermal model for the S-Z surface brightness. Since the cluster is asymmetrical and probably in a merging process, models are only approximate. The associated uncertainty can, however, be estimated by exploring a set of alternative models. We then find as the global uncertainty on the Comptonization parameter a factor of 1.3. Combining the S-Z and the X-ray measurements, we determine a value for the Hubble constant. The 2 mm data are consistent with H_0(q_0 = 1/2)= 53^{+38}_{-28} km/s Mpc^{-1}, where the uncertainty is dominated by the uncertainty in models of the X-ray plasma halo.

The need for accurate and complete maps of the galaxy at radio frequencies is made evident not only by the importance of the data in the study of galactic dynamics and structure formation but also in the analysis of cosmic background radiation data. A summary of the existing radio surveys of our galaxy is presented along with their limitations. A new program, the Galactic Emission Mapping (GEM) project, to obtain calibrated and complete maps of the galaxy in the 400 to 1400 MHz range, is outlined.

COCHISE (Cosmological Observations at Concordia with High-sensitivity Instrument for Source Extraction) is a 2.6 m telescope located on the high Antarctic Plateau near the Italian-French Concordia Base. The telescope is mainly devoted to Cosmological observations, able to operate between 200 mu m and 3 mm of wavelength. In this paper we describe the main characteristics of the instrument. We also report on the first light, obtained during summer 2010-2011: this result marks the beginning of millimetre astrophysical observations at Concordia. Responsivity, noise equivalent temperature and field of view of the instrument are reported. At present COCHISE is the largest telescope located at Concordia. Beside the scientific expectations, the use of this kind of instrument in the Antarctic environment poses technological aspects of relevant interest: thus COCHISE can be considered as a pathfinder for future Antarctic telescopes.

OASI (Infrared and Sub-mm Antarctic Observatory) is the first large telescope permanently installed in Antarctica. It is located close to the Italian Base in Antarctica (Terra Nova Bay Station, latitude: 74.39 S, longitude: 164.09 E). The OASI first light was received in December 1990 when the wobbling secondary mirror was mounted. The telescope is planned to be an open facility which can operate in the wavelengths range between 350 μm and 3mm. The sky coverage from OASI goes down to a declination of about-35° for a 24 hours/day observing time.

My story with Francesco

The OASI group have been active in Antarctica since 1986: from the pioneering period, though the 2.62 m mm telescope activity at Terra Nova Bay to the first observing campaigns at Dome C. The group activity significantely contributed to the development of mm Italian Antarctic astronomy, acting as a pathfinder for present success and future development. The overall italian activity is characterised by interesting scientific results, obtained even when adequate funding was not available. The historical evolution of the italian mm activities in Antarctica will be illustrated and the perspective for future experiments will be reported.

We report on millimetric continuum observations of two bright compact H II regions, which have been observed for the first time in this frequency range. For the two observed regions (G291.6-0.5 and G291.3-0.7), we derive the flux densities at the two observed wavelengths (1.25 and 2 mm) as well as the spectral index and the temperature of the surrounding dust by fitting a modified blackbody curve to our results combined with IR values obtained from the literature. We also estimate the dust mass and the bolometric luminosity of the two regions.

COMPASS is an on-axis 2.6 meter telescope coupled to a correlation polarimeter. The entire instrument was built specifically for CMB polarization studies. Careful attention was given to receiver and optics design, stability of the pointing platform, avoidance of systematic offsets, and development of data analysis techniques. Here we describe the experiment, its strengths and weaknesses, and the various things we have learned that may benefit future efforts to measure the polarization of the CMB., To be published in the proceedings of "The Cosmic Microwave Background and its Polarization", New Astronomy Reviews, (eds. S. Hanany and K.A. Olive)

Preliminary site testing at Dome C (Antarctica) is presented, using both Automatic Weather Station (AWS) meteorological data (1986-1993) and Precipitable Water Vapor (PWV) measurements made by the authors. A comparison with South Pole and other sites is made. The South Pole is a well established astrophysical observing site, where extremely good conditions are reported for a large fraction of time during the year. Dome C, where Italy and France are building a new scientific station, is a potential observing site in the millimetric and sub-millimetric range. AWS are operating at both sites and they have been continuously monitoring temperature, pressure, wind speed and direction for more than ten years. Site testing instruments are already operating at the South Pole (AASTO, Automated Astrophysical Site-Testing Observatory), while ''light'' experiments have been running at Dome C (APACHE, Antarctic Plateau Anisotropy CHasing Experiment) during summertime. A direct comparison between the two sites is planned in the near future, using the AASTO. The present analysis shows that the average wind speed is lower at Dome C (~1 m/s) than at the South Pole (~2 m/s), while temperature and PWV are comparable., 10 pages, 8 figures, se also http://www.atnf.csiro.au/pasa/16_2/

We report on observations of the Sunyaev-Zeldovich effect toward X-ray ROSAT clusters taken with a double-channel (1.2 and 2 mm) photometer installed at the focus of the 15 m Swedish ESO Submillimeter Telescope antenna in Chile. This paper describes the first results obtained for the high-z clusters S1077, A2744, and S295. Marginal detections were found for A2744, and at 1 mm for S1077. We discuss these data in terms of contamination of sources along the line of sight and give a constraint on the amplitude of the kinematic effect.

A balloon-borne experiment has been conceived in order to map the sub-millimetric galactic emission at four different wavelengths between 400 μm and 2 mm at an angular scale of 1°. Such measurements will make it possible both to investigate the nature of the interstellar dust and to disentangle the galactic contribution from extragalactic and cosmological signals. A binocular telescope system has been realized by means of two 37 cm of-axis wobbling parabolic mirrors, each one coupled with a two-channel 3He photometer. The first trans-Mediterranean flight is scheduled for summer 1995.

A double channel (1.2 and 2 mm) photometer has been installed at the focus of the 15m SEST antenna in Chile to perform measurements of the Sunyaev-Zeldovich effect towards X-ray ROSAT clusters. This paper describes the instrument and the characteristics of the system: its sensitivity, field of view, noise and the performed calibrations.

Millimetric continuum observations of the Galactic disk at b about -8 deg and l about 290-310 deg has been achieved during the Italian 1987-1988 scientific expedition in Antarctica. Emission was detected from few southern clouds (the Chamaeleon region and a cirrus cloud), and their energy distributions reveal an excess in the long wavelength range. This fact is interpreted as being due to the presence of a cold component of the interstellar material coexisting with the warm dust responsible for the emission detected by IRAS. Then, a multiple nature of the interstellar dust is suggested also in regions far from the Galactic bulge. 45 refs.

Millimetric observations (1-2 mm) toward the Magellanic Clouds from Antarctica show a good spatial correlation with the IRAS 100-micron emission in the same sky regions. Very likely a cold component coexisting with the warm dust detected by IRAS has been observed. 18 refs.

Results concerning zodiacal dust emission are reported from an IR sky survey experiment performed during a balloon flight on July 30, 1984 which explored five wavelength bands centered at 11, 19, 50, 108, and 225 microns. The dust density n decreases at a rate slower than r exp -1.3 with increasing heliocentric distance. The trend of n depends critically on the radial variation of the temperature which, in turn, depends on the chemical composition of the grains. The spatial distribution of the dust is in good agreement with that previously inferred from IR measurements. A comparison between IR and optical observations points out the uncertainties affecting the estimates of the dust density obtained with both methods. The emission spectrum of the dust is used to discriminate among the different species of grains, showing that the observations can be accounted for by an appropriate mixture of graphite and silicates. 18 references.

An experiment has been developed in order to map the submillimetre Galactic emission at four different wavelengths between 400 μm and 2 mm at an angular scale of 1°. A binocular telescope system has been realised by means of two off-axis wobbling parabolic mirrors, each one coupled to a two-channel 3He photometer. A first run of observations from Dome C is planned for the Antarctic summer 1995–96.

An infrared search for the Sunyaev-Zeldovich effect toward the intergalactic ''void'' discovered by Kirshner et al. has given a null result within 1 x 10/sup -4/ K at 1 standard deviation. The result implies that the change of the Comptonization parameter toward the hole is less than 2 x 10/sup -2/. From the hypothesis that the hot gas is absent in the hole, we get an upper limit 0.5 for the normalized density of the extragalactic gas.

A ground-based experiment has been carried out in Terra Nova Bay, Antarctica in order to detect anisotropies in cosmic background radiation at an angular scale of 1.3 deg. A 1-m-diameter flux collector and an He-3-cooled bolometric detector sensitive to radiation with a wavelength between 1.86 and 2.34 mm are used. Observations were carried out during the Antarctic summer and are limited by atmospheric emission fluctuations. 13 references.

On a analyse les correlations existant entre l'emission dans l'IR lointain de la poussiere interstellaire, les comptages de galaxies et l'emission de l'hydrogene atomique a 21 cm. On en conclut que le signal IR est le meilleur indicateur de poussiere disponible. Les correlations donnent egalement des informations concernant l'heterogeneite de la distribution des galaxies et la densite de colonne de l'hydrogene moleculaire

A new method is discussed for measuring the extragalactic diffuse radiation in the 100--1000 ..mu..m region, in the presence of the strong local sources like atmospheric, interplanetary, and galactic dust emission. The method consists of the search for a peculiar spatial signature of the extragalactic component, i.e., its dipole anisotropy due to the observers' motion, which has to be aligned with the 3 K dipole anisotropy. Using the observations available at 11 cm/sup -1/, 14 cm/sup -1/, 25 cm/sup -1/, and 50 cm/sup -1/, we derived upper limits of the order of 2 x 10/sup -12/ watts cm/sup -2/ sr/sup -1//cm/sup -1/ between 13 and 18 cm/sup -1/ for the diffuse radiation emitted by rich clusters, and of 5 x 10/sup -12/ watts cm/sup -2/ sr/sup -1//cm/sup -1/ for radiation emitted by infrared galaxies at 1 standard deviation. Our analysis excludes an extragalactic origin for the infrared excess observed by Gush at 16--17 cm/sup -1/ at 2 standard deviations.