ADC/CDS Standard Document for Catalog:/journal_tables/A+A/384/650/
ADC/CDS Standard Document for Catalog:| 1. Use the ADC Data Viewer Suite to visualize the data. |
|
| 2. Get the data files via anonymous FTP. (See Note.) |
|
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 {lambda}=5635{AA}, 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 <oat1@on.br>
================================================================================
(End) Patricia Bauer [CDS] 22-Feb-2002