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J/A+A/384/650       CCD solar diameter measurements in 1999-2000 (Penna+, 2002)

CCD astrolabe solar diameter measurements in 1999-2000 Penna J.L., Jilinski E.G., Andrei A.H., Puliaev S.P., Reis Neto <Astron. Astrophys. 384, 650 (2002)> =2002A&A...384..650P
ADC_Keywords: Sun Keywords: Sun: activity - Sun: fundamental parameters Abstract: Solar diameter observations are presented covering a period close to the maximum of the solar activity cycle 23, from July 1999 to December 2000, at the Observatorio Nacional, Rio de Janeiro. The observations were made at λ=5635Å, with a CCD Solar Astrolabe, thus timing the limb crossing through a fixed zenith distance. The formal precision of a single measurement is typically 0.18". The results represent daily means from 4625 independent measurements. The series obtained has 225 homogeneously distributed points with a mean precision of 0.12". The average value obtained for the solar semi-diameter within the analyzed period is 959.01"±0.02". The average of the observations, made under a wide range of different geometric, instrumental and environmental conditions, aims to provide results representing global variations of the solar radius. From this data, variations with amplitude equal to or larger than 0.02" can be investigated. No statistically significant linear trend is obtained for the examined series. There is, however, some indication of an increasing trend for 1999 followed by a stabilization during 2000. Periodic variations are obtained with amplitudes between 0.02" and 0.07". Periods related to the solar rotation and the sunspot characteristic lifetime can be recognized. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table.dat 48 225 Daily average solar semi-diameter observed at Observatorio Nacional - Rio de Janeiro
See also: J/A+A/375/614 : Astrolabe observations of the Sun in 1990-2000 (Noel, 2001) J/A+AS/132/195 : Astrolabe observations of the Sun in 1995-1997 (Noel 1998) J/A+AS/102/11 : Astrolabe observations of the Sun in 1990-1992 (Noel 1993) J/A+AS/113/131 : Observations of the Sun during 1994 (Noel, 1995) J/A+AS/106/327 : Observations of the Sun during 1993 at Santiago (Noel 1994) J/A+AS/110/351 : Sun observations in 1992 (Sanchez+, 1995) Byte-by-byte Description of file: table.dat
Bytes Format Units Label Explanations
1- 10 A10 "YYYY/MM/DD" Date Date of the observation 12- 18 I7 d MJD Modified Julian Date of the observation 20- 21 I2 --- Nobs Number of independent observations (see paper for observations discarding criteria) 23- 28 F6.2 arcsec <SD> Average Daily Semi-diameter 30- 33 F4.2 arcsec e_<SD> rms uncertainty on <SD> 35- 38 F4.2 arcsec sigma Standard deviation of the used daily observations 40- 43 F4.1 arcsec Zmin Minimum observed zenith distance, among the used daily observations 45- 48 F4.1 arcsec Zmax Maximum observed zenith distance, among the used daily observations
Acknowledgements: Alexandre Humberto Andrei
(End) Patricia Bauer [CDS] 22-Feb-2002
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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