J/ApJS/141/31 JHK' imaging photometry of Seyfert 1. II. (Enya+, 2002)
JHK' imaging photometry of Seyfert 1 active galactic nuclei and quasars.
II. Observation of long-term variability.
Enya K., Yoshii Y., Kobayashi Y., Minezaki T., Suganuma M., Tomita H.,
Peterson B.A.
<Astrophys. J. Suppl. Ser. 141, 31 (2002)>
=2002ApJS..141...31E 2002ApJS..141...31E
ADC_Keywords: Active gal. nuclei ; QSOs ; Photometry, infrared
Keywords: galaxies: active - galaxies: photometry - galaxies: Seyfert -
infrared: galaxies - quasars: general
Abstract:
Observations of 226 AGNs in the near-infrared J, H, and K' bands are
presented along with the analysis of the observations for variability.
Our sample consists mainly of Seyfert 1 AGNs and QSOs. About a quarter
of the objects in each category are radio loud. The AGNs in the entire
sample have the redshifts spanning the range from z=0 to 1, and the
absolute magnitudes from MB=-29 to -18. All the objects were
observed twice, and their variability was measured by differential
photometry. A reduction method of differential photometry, optimized
to the analysis of extended images, has been developed. The systematic
error in variability arising from AGNs of highly extended images is
estimated to be less than 0.01mag in each of the J, H, and K' bands.
The systematic error arising from the flat-fielding is negligible for
most AGNs, although it is more than 0.1mag for some particular cases.
The overall average flat-fielding error is 0.03mag for the image
pairs. We find that these systematic errors are superseded by
statistical errors, and the overall average total systematic and
statistical errors amounts to 0.05mag in the measured variability in
each band.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 90 212 Variability data of 226 AGNs
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See also:
VII/224 : Quasars and Active Galactic Nuclei (10th Ed.) (Veron+ 2001)
J/ApJS/141/23 : JHK' imaging photometry of Seyfert 1. I. (Enya+, 2002)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Num Target AGN number
5- 19 A15 --- Name AGN name
21- 26 F6.3 mag dJmag ? J band differential photometry
variability
28- 32 F5.3 mag e_dJmag ? The error in dJmag
34- 35 I2 --- o_dJmag ? Number of reference objects used in dJmag
37- 42 F6.3 mag dHmag ? H band differential photometry
variability
44- 48 F5.3 mag e_dHmag ? The error in dHmag
50- 51 I2 --- o_dHmag ? Number of reference objects used in dHmag
53- 58 F6.3 mag dK'mag ? K' band differential photometry
variability
60- 64 F5.3 mag e_dK'mag ? The error in dK'mag
66- 67 I2 --- o_dK'mag ? Number of reference objects used in
dK'mag
69- 78 A10 "YYYY/MM/DD" Obs1 Date of first observation
80- 89 A10 "YYYY/MM/DD" Obs2 Date of second observation
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Bauer [CDS] 09-Jul-2002