scholarly journals A Southern Hemisphere Survey of the Galactic Plane at 5 GHz

1978 ◽  
Vol 31 (4) ◽  
pp. 351
Author(s):  
RF Haynes ◽  
JL Caswell ◽  
LWJ Simons

Seventy five maps are presented showing the 5 GHz emission from the galactic plane in the range I = 190� ~ 360� .... 40� for - 2� < b < 2� (an area of approximately 600 square egrees). The method of observing and the computer reduction of the data are discussed. the telescope resolution is 4'�1 arc to half-power points and the detection limit for point sources is better than 0�5 Jy.

1968 ◽  
Vol 21 (6) ◽  
pp. 881 ◽  
Author(s):  
FF Gardner ◽  
M Morimoto

The continuum radiation from about 36 southern thermal radio sources has been surveyed at 6 cm wavelength with a beamwidth of 4'�2 arc, and maps are shown for 28 of these. The positional accuracy is better than l' arc.


1987 ◽  
Vol 115 ◽  
pp. 158-160
Author(s):  
Hisashi Hirabayashi ◽  
Kenji Akabane ◽  
Masaki Morimoto ◽  
Yosiaki Sofue ◽  
Makato Inoue ◽  
...  

The Sgr B2 region was mapped at 43 GHz (λ = 6.9 mm) with the 45m radio telescope of Nobeyama Radio Observatory. The observing parameters were: a) half power beamwidth 38″, b) pointing accuracy better than 10″, c) central frequency 43.0 GHz, d) bandwidth 500 MHz, and e) system noise temperature 400 K; and the observational aspects were: a) mapping with one polarization, b) liquid-nitrogen cooled load switching and c) reduction by NOD-2 programme. The obtained map is shown in Figure 1. Sgr B2 is resolved into several components which correspond to those by Martin and Downes (1972) and Downes et al. (1978). But the component at RA = 17h44m11.8s Dec. = −28°23′55″ at 1950 is not seen in Martin and Downes (1972) nor in the 5 GHz map of Downes et al. (1978), although the feature is seen in the 10.7 GHz map of Downes et al. (1978). The components derived from the map in Figure 1 by a morphological estimate are listed in Table 1. The total flux density of the region is 146J±30 Jy. The intensity calibration was made by observing NGC 7027.


1983 ◽  
Vol 71 ◽  
pp. 429-437
Author(s):  
P.A. Feldman

This is a summary of the systematic program of A3cm radio observations of RS CVn and similar binaries which has been carried out since 1977 at the Algonquin Radio Observatory. The observations were made at X-band frequencies (10-11 GHz) with the 46m telescope using the same observing procedures described in Feldman et al. (1978). The detection limit is generally 25 mJy, although it is possible to do somewhat better than this if the star is located well off the galactic plane and if it maintains an elevated flux level (i.e. ≳ 15 mJy) for several hours. The observing list has grown roughly four-fold since the start of the program in 1977. It now encompasses 65 of the 69 “bona fide” RS CVn binaries compiled by Hall (1982); the rest are suspected RS CVn binaries, BY Dra variables, Algol-type binaries, and W UMa binaries. To date, a total of some 85 observing days, representing more than 1000 hours of telescope time, has been devoted to this program.


1997 ◽  
Vol 161 ◽  
pp. 611-621
Author(s):  
Guillermo A. Lemarchand ◽  
Fernando R. Colomb ◽  
E. Eduardo Hurrell ◽  
Juan Carlos Olalde

AbstractProject META II, a full sky survey for artificial narrow-band signals, has been conducted from one of the two 30-m radiotelescopes of the Instituto Argentino de Radioastronomía (IAR). The search was performed near the 1420 Mhz line of neutral hydrogen, using a 8.4 million channels Fourier spectrometer of 0.05 Hz resolution and 400 kHz instantaneous bandwidth. The observing frequency was corrected both for motions with respect to three astronomical inertial frames, and for the effect of Earths rotation, which provides a characteristic changing signature for narrow-band signals of extraterrestrial origin. Among the 2 × 1013spectral channels analyzed, 29 extra-statistical narrow-band events were found, exceeding the average threshold of 1.7 × 10−23Wm−2. The strongest signals that survive culling for terrestrial interference lie in or near the galactic plane. A description of the project META II observing scheme and results is made as well as the possible interpretation of the results using the Cordes-Lazio-Sagan model based in interstellar scattering theory.


1998 ◽  
Vol 11 (1) ◽  
pp. 551-551
Author(s):  
N. Zacharias ◽  
M.I. Zacharias ◽  
C. de Vegt ◽  
C.A. Murray

The Second Cape Photographic Catalog (CPC2) contains 276,131 stars covering the entire Southern Hemisphere in a 4-fold overlap pattern. Its mean epoch is 1968, which makes it a key catalog for proper motions. A new reduction of the 5687 plates using on average 40 Hipparcos stars per plate has resulted in a vastly improved catalog with a positional accuracy of about 40 mas (median value) per coordinate, which comes very close to the measuring precision. In particular, for the first time systematic errors depending on magnitude and color can be solved unambiguously and have been removed from the catalog. In combination with the Tycho Catalogue (mean epoch 1991.25) and the upcoming U.S. Naval Observatory CCD Astrograph Catalog (UCAC) project proper motions better than 2 mas/yr can be obtained. This will lead to a vastly improved reference star catalog in the Southern Hemisphere for the final Astrographic Catalogue (AC) reductions, which will then provide propermotions for millions of stars when combined with new epoch data. These data then will allow an uncompromised reduction of the southern Schmidt surveys on the International Celestial Reference System (ICRS).


1988 ◽  
Vol 66 (1) ◽  
pp. 174-177 ◽  
Author(s):  
E. Haddad ◽  
L. Zikovsky

A new method for the determination of Sr-90 dissolved in surface waters has been developed. It is based on the precipitation of Sr with 8-hydroxyquinoline at pH 11.3 and counting of β particles with energy above 150 keV. The detection limit obtained is 0.5 mBq/L and the mean yield is 28%. The decontamination factors from other β emitters achieved are better than 10 000. This method has been used to measure the Sr-90 in 5 lakes and 5 rivers in Québec and activities ranging from 3 to 15 mBq/L were obtained. This new method is as efficient and reliable as conventional techniques while being less tedious.


1981 ◽  
Vol 4 (2) ◽  
pp. 247-250 ◽  
Author(s):  
K. N. R. Taylor ◽  
R. Llewellyn ◽  
P. Payne ◽  
R. A. Vaile ◽  
S. Sakellis

Coronae Austrinae is one of the few star formation areas lying well away from the galactic plane (l = 360°, b = −17°) and is visible predominantly from the Southern Hemisphere.


1981 ◽  
Vol 59 ◽  
pp. 179-180
Author(s):  
M. Felli ◽  
N. Panagia

Eight O-type giants and supergiants, selected for being relatively isolated in the sky, have been observed at 5 GHz with 17 antennae of the partially completed VLA (NRAO, Socorro, New Mexico: The National Radio Astronomy Observatory is operated by Associated Universities under contract with the National Science Foundation) on October 7 and 8, 1979. The integration times ranged between 38 and 187 minutes. The results are displayed in Table 1. Most of the stars (6 out of 8) were not detected. The upper limits given in Table 1 for these stars correspond to the 3σ noise level. Possible detection has been achieved for the two supergiants HD 225160 and HD 30614 both with a flux density of 0.15 mJy. Although this flux is equal to the 3a noise level, the detections can be considered to be real because 1) Excellent positional coincidence is found between stars and the radio peaks (better than 1”) 2) The observed source pattern corresponds very well to the expected response to a point-like source.


2019 ◽  
Vol 207 ◽  
pp. 01001
Author(s):  
Antoine Kouchner

Antares, the first undersea neutrino telescope, has been continuously operating since 2007 in the Mediterranean Sea. The transparency of the water allows for a very good angular resolution in the reconstruction of neutrino events of all flavors. This results in an unmatched sensitivity for neutrino source searches, in a large fraction of the Southern Sky, at TeV energies. As a consequence, Antares provides valuable constraints on the origin of the cosmic neutrino flux discovered by the IceCube Collaboration. Based on an all-flavor dataset spanning nine years of operation of the detector, the latest results of Antares searches for neutrino point sources, and for diffuse neutrino emission from the entire sky as well as from several interesting regions such as the Galactic Plane, are presented. Several results have been obtained through a joint analysis with the IceCube Collaboration. Concerning the multi-messenger program, the focus is made on the follow-up searches of IceCube alerts, in particular the one related to the TXS 0506+056 blazar, thought to be the first extragalactic high-energy neutrino source identified so far.


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