Absolute flux measurements of Cassiopeia-A, Cygnus-A, Taurus-A, and Virgo-A at seven wavelengths between 1.8?4.2 cm

1981 ◽  
Vol 24 (1) ◽  
pp. 9-13
Author(s):  
L. V. Dmitrenko ◽  
V. V. Snegireva ◽  
V. I. Turchin ◽  
N. M. Tseitlin ◽  
L. A. Voronkov ◽  
...  
Keyword(s):  
Cassiopeia A ◽  
Absolute Flux ◽  
Cygnus A ◽  
Flux Measurements

scholarly journals Infrared Absolute Calibration. I. Comparison of Sirius with Fainter Calibration Stars

2022 ◽  
Vol 163 (2) ◽  
pp. 45
Author(s):  
G. H. Rieke ◽  
Kate Su ◽  
G. C. Sloan ◽  
E. Schlawin
Keyword(s):  
Near Infrared ◽  
Spectral Energy Distribution ◽  
Spectral Energy ◽  
Absolute Calibration ◽  
Absolute Flux ◽  
James Webb Space Telescope ◽  
Infrared Spectral ◽  
History Of ◽  
Flux Measurements ◽  
Debris Disk

Abstract A challenge in absolute calibration is to relate very bright stars with physical flux measurements to faint ones within range of modern instruments, e.g., those on large ground-based telescopes or the James Webb Space Telescope (JWST). We propose Sirius as the fiducial color standard. It is an A0V star that is slowly rotating and does not have infrared excesses due to either hot dust or a planetary debris disk; it also has a number of accurate (∼1%–2%) absolute flux measurements. We accurately transfer the near-infrared flux from Sirius to BD +60 1753, an unobscured early A-type star (A1V, V ≈ 9.6, E(B – V) ≈ 0.009) that is faint enough to serve as a primary absolute flux calibrator for JWST. Its near-infrared spectral energy distribution and that of Sirius should be virtually identical. We have determined its output relative to that of Sirius in a number of different ways, all of which give consistent results within ∼1%. We also transfer the calibration to GSPC P330-E, a well-calibrated close solar analog (G2V). We have emphasized the 2MASS K S band, since it represents a large number and long history of measurements, but the theoretical spectra (i.e., from CALSPEC) of these stars can be used to extend this result throughout the near- and mid-infrared.

scholarly journals The structure of the Cassiopeia A and Cygnus A radio sources measured at 127 Mc/s and 3000 Mc/s

1959 ◽  
Vol 9 ◽  
pp. 309-314
Author(s):  
R. C. Jennison
Keyword(s):  
Position Angle ◽  
Brightness Distribution ◽  
Radio Sources ◽  
Cassiopeia A ◽  
The Third ◽  
Cygnus A ◽  
Main Component ◽  
Main Region

The brightness distribution across the Cassiopeia A source in position angle 90 degrees consists of a primary region of emission 4.1 minutes of arc in width, with a much fainter extension offset from the main region of emission and having a brightness of only 10 per cent of that of the main component. Measurements were made up to the third maximum of the transform (2160 λ), and the position of the first zero was determined at 840 λ.

scholarly journals Power Spectrum of the Density of Cold Atomic Gas in the Galaxy toward Cassiopeia A and Cygnus A

2000 ◽  
Vol 543 (1) ◽  
pp. 227-234 ◽  
Author(s):  
A. A. Deshpande ◽  
K. S. Dwarakanath ◽  
W. M. Goss
Keyword(s):  
Power Spectrum ◽  
Cassiopeia A ◽  
Cygnus A ◽  
The Galaxy ◽  
Atomic Gas

Absolute measurements of the intensity of radio emission from Cassiopeia-A, Cygnus-A, and Taurus-A in the 3?15 cm range of wavelengths

1970 ◽  
Vol 13 (6) ◽  
pp. 649-654 ◽  
Author(s):  
D. A. Dmitrenko ◽  
N. M. Tseitlin ◽  
L. V. Vinogradova ◽  
Kh. F. Giterman
Keyword(s):  
Radio Emission ◽  
Cassiopeia A ◽  
Cygnus A ◽  
Absolute Measurements
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