J/A+AS/129/577 AO 0235+164 BVRI photometry (Takalo+ 1998)
Monitoring of AO 0235+164 during a faint state
Takalo L.O., Sillanpaa A., Valtaoja E., Katajainen S., Nilsson K.
Pursimo T., Heinamaki P., Villata M., Raiteri C.M., Ghisellini G.,
De Francesco G., Lanteri L., Chiaberge M., Peila A., Boltwood P.,
Tosti G., Fiorucci M., Terasranta H., Tornikoski M., Teerikorpi P.
<Astron. Astrophys. Suppl. Ser. 129, 577 (1998)>
=1998A&AS..129..577T 1998A&AS..129..577T (SIMBAD/NED BibCode)
ADC_Keywords: BL Lac objects ; Photometry, UBVRI
Keywords: BL Lac objects: general; AO 0235+164 - gravitational lensing
Abstract:
We present the results of the optical and radio monitoring of the BL
Lac object AO 0235+164 during a faint state. In both optical and radio
bands the source has been observed at the faintest ever recorded
levels, reaching V=19.80 and F22GHz=0.34Jy. In the optical bands we
still see variability with amplitudes up to 1.5 magnitudes on
timescales from days to weeks. The radio variability is less dramatic,
but in general follows the optical behaviour. A correlation between
general trends in the optical and radio behaviour of AO 0235+164 may
be recognized in the data from the present monitoring as well as in
the historical light curves, suggesting a `base' mechanism responsible
for the emission at both frequencies. A good candidate is a
synchrotron process in the relativistic jet. Optical flares with no
corresponding radio counterparts have been observed too. These events
may be interpreted in terms of microlensing by a foreground galaxy.
Objects:
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RA (2000) DE Designation(s)
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02 38 38.9 +16 36 59 AO 0235+16 = QSO 0235+164
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 59 80 The optical observations
table2.tex 75 108 LaTeX version of table2
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 11 F11.3 d HJD Heliocentric Julian date
13- 17 F5.2 mag Bmag ? B magnitude
19- 22 F4.2 mag e_Bmag ? rms uncertainty on Bmag
24- 28 F5.2 mag Vmag ? V magnitude
30- 33 F4.2 mag e_Vmag ? rms uncertainty on Vmag
35- 39 F5.2 mag Rmag ? R magnitude
41- 44 F4.2 mag e_Rmag ? rms uncertainty on Rmag
46- 50 F5.2 mag Imag ? I magnitude
52- 55 F4.2 mag e_Imag ? rms uncertainty on Imag
57- 59 A3 --- Obs Observer (1)
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Note (1): NOT: North Optical Telescope, La Palma, 2.5m, BVRI
JKT: Jacobus Kapteyn telescope, La Palma, 1.0m, VR
TO: Torino, 1.05m, R
TU: Tuorla, 1.03m, V
BO: Boltwood, 17cm, VRI
PE: Perugia, 40cm, VRI
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(End) Patricia Bauer [CDS] 21-Nov-1997