26.3-MHz radio source survey. I - The absolute flux scale

1975 ◽  
Vol 80 ◽  
pp. 83 ◽  
Author(s):  
M. R. Viner

JETP Letters ◽  
2008 ◽  
Vol 88 (7) ◽  
pp. 411-413 ◽  
Author(s):  
G. F. Krymsky ◽  
V. G. Grigor’ev ◽  
S. A. Starodubtsev


1980 ◽  
Vol 88 ◽  
pp. 549-553
Author(s):  
R. Faraggiana

IUE spectra of VV Cep have been obtained in 1978 and 1979 during the chromospheric phase of the eclipse. The profiles of the Mg II resonance lines differ from one another and this peculiarity, common to other M type supergiants, is examined. The value of Mv derived from the extension of the Wilson and Bappu relation to Mg II lines is compared with other determinations. The variation of the absolute flux in the 1200-2000 Å range is presented.





Author(s):  
J. B. Foster ◽  
J. M. Rathborne ◽  
P. Sanhueza ◽  
C. Claysmith ◽  
J. S. Whitaker ◽  
...  

AbstractWe characterise the Millimetre Astronomy Legacy Team 90 GHz Survey (MALT90) and the Mopra telescope at 90 GHz. We combine repeated position-switched observations of the source G300.968+01.145 with a map of the same source in order to estimate the pointing reliability of the position-switched observations and, by extension, the MALT90 survey; we estimate our pointing uncertainty to be 8 arcsec. We model the two strongest sources of systematic gain variability as functions of elevation and time-of-day and quantify the remaining absolute flux uncertainty. Corrections based on these two variables reduce the scatter in repeated observations from 12%–25% down to 10%–17%. We find no evidence for intrinsic source variability in G300.968+01.145. For certain applications, the corrections described herein will be integral for improving the absolute flux calibration of MALT90 maps and other observations using the Mopra telescope at 90 GHz.



2010 ◽  
Vol 49 (2) ◽  
pp. 221-233 ◽  
Author(s):  
M. Sofiev ◽  
E. Genikhovich ◽  
P. Keronen ◽  
T. Vesala

Abstract The problem of providing dispersion models with meteorological information from general atmospheric models used, for example, for weather forecasting is considered. As part of a generalized meteorological-to-dispersion model interface, a noniterative scheme diagnosing the surface layer characteristics from wind, temperature, and humidity profiles was developed. The scheme verification included long-term comparison with data of meteorological masts at Cabauw, the Netherlands, and Hyytiälä, Finland. The algorithm compatibility and consistency with the High-Resolution Limited-Area Model (HIRLAM) was also checked, as this model is routinely used as a meteorological driver for the Air Quality and Emergency Modeling System (SILAM). The comparison with Cabauw mast data showed a good quantitative agreement between observed and diagnosed heat and momentum fluxes: the temporal correlation coefficient was ∼0.8, bias was less than 10% of the absolute flux levels, regression slope deviated from unity for less than 20% with the intercept being less than 10% of the absolute flux values, and so on. In the case of complex surface features (Hyytiälä mast in forest) the scheme proved to be robust with large deviations appearing only if the input profile data were taken outside the constant-flux layer. Comparison with the HIRLAM model showed qualitatively good agreement but also highlighted several differences between the goals, standards, and methodologies of meteorological and dispersion models. The scheme was implemented in SILAM, which served as the development platform.





1970 ◽  
Vol 1 (8) ◽  
pp. 378-379 ◽  
Author(s):  
J. Davis ◽  
R. J. Webb

The angular diameter of a star, combined with observed stellar fluxes in absolute units, allows the absolute fluxes emitted at the surface of the star to be calculated and thus provides a stringent test of model atmosphere predictions. Furthermore, if the flux distribution is observed at all wavelengths contributing significantly to the net flux, an empirical effective temperature can be found. Sufficient data are now available for Sirius (αCMa) to be studied in this way.



1990 ◽  
Vol 122 ◽  
pp. 159-160 ◽  
Author(s):  
J. Mikołajewska ◽  
M. Mikołajewski

PW Vul (Nowa Vul 1984 #1) was a slow classical nova which began its outburst in July 1984 and reached optical maximum in the first week of August 1984. Eight low dispersion spectra (160 A/mm) in the blue spectral range (λλ3400-5100 A) were secured between October 1984 and July 1985, with the CCS spectrograph equipped with 3.5 arcsec aperture image slicer and mounted on 90 cm Schmidt-Cassegrain telescope at Toruń Observatory. Kodak IIa-O plates were used. In addition two moderate dispersion (40 A/mm) spectra in the Hγ-Hβ range were obtained on 28 October and 3 November 1984, using the same instrumentation. Standard stars were observed on each night to remove the influence of spectral sensitivity of the photographic emulssion and atmospheric extinction. The calibration of the absolute flux scale was performed by comparing synthetic B magnitudes calculated from our spectra with published B photometry of PW Vul (Voloshina 1985, Noskova et al. 1985, Kolotilov and Noskova 1986). The accuracy of the flux calibration is ±0.1 mag.



1973 ◽  
Vol 183 ◽  
pp. 1081 ◽  
Author(s):  
Duane O. Muhleman ◽  
Glenn L. Berge ◽  
Glenn S. Orton


2008 ◽  
Vol 135 (3) ◽  
pp. 1092-1098 ◽  
Author(s):  
R. C. Bohlin ◽  
D. Koester


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