Lens System Summary
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This Lens System
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Lens name
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B0827+525
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Survey
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CLASS
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Images
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2
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B1950.0 coords
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08h27m22.357s
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52°35'27.580"
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J2000.0 coords
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08h31m05.362s
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52°25'20.241"
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Lens System Structure and Labelling
Image labelling for this lens (RA increases to the left, declination increases upwards)
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Image/Lens Positions
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Image/Lens
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Relative Position
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East (mas)
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North (mas)
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A1
|
+1064.02
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+930.74
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A2
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+1063.18
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+929.89
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B1
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-1074.16
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-900.40
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B2
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-1076.43
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-899.78
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Image/Lens Separations
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Separation (mas)
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Component
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A1
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A2
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B1
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B2
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A1
|
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1.2
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2815.1
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2816.4
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A2
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1.2
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2813.9
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2815.2
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B1
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2815.1
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2813.9
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2.4
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B2
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2816.4
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2815.2
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2.4
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Position angle (°)
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Component
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A1
|
A2
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B1
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B2
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A1
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44.7
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49.4
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49.5
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A2
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-135.3
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49.4
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49.5
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B1
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-130.6
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-130.6
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105.3
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B2
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-130.5
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-130.5
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-74.7
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Maps and Images
Click on an image to see a larger JPEG version, or click on the accompanying text to
download a gzipped FITS or PostScript file of the map or image. The images and maps are
available in one gzipped file here.
To see a DSS image of the region around this lens, click here - note that you will have to start the search manually by clicking on the 'Search' button.
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Radio Flux Densities
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Component
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Flux density (mJy)
|
|
1.4 GHz
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1.4 GHz
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5 GHz
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4.9 GHz
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5 GHz
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8.5 GHz
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15 GHz
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22 GHz
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A
|
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42.3±0.3
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33.1±0.1
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~34.0
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29.7±0.1
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29.1±0.4
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A1
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|
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24.8±0.1
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|
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A2
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6.8±0.1
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B
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27.4±0.3
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14.0±0.1
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~14.8
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10.7±0.1
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8.0±0.4
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B1
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9.3±0.1
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B2
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3.6±0.1
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Total
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71-58
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Flux errors
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Resolution (mas)
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1500
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2.5
|
50
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Map noise level
(mJy/beam)
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0.256
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0.133
|
0.123
|
0.063
|
|
0.383
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Instrument
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WSRT
|
VLA
|
VLA
|
VLBA
|
MERLIN
|
VLA
|
VLA
|
VLA
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Date observed
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1997/07-09
|
1999/06/27
|
1999/06/27
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1997/08/02
|
1997/12/08
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1999/06/27
|
1999/06/27
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|
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Reference
|
[2]
|
[2]
|
[2]
|
[2]
|
[2]
|
[2]
|
[2]
|
|
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Sub-millimetre Flux Densities
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Component
|
Flux density (mJy)
|
|
850 μm
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450 μm
|
|
Total
|
84±3
|
285±11
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Estimated
cal. error
|
5-10%
|
5-10%
|
|
Instrument
|
SCUBA (JCMT)
|
SCUBA (JCMT)
|
|
Date observed
|
1999-2001
|
1999-2001
|
|
Reference
|
[3]
|
[3]
|
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Optical Imaging
|
Component
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Brightness (Magnitudes)
|
|
K
|
R
|
H
|
|
A
|
Detected
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~22.0-22.5
|
19.6±0.2
|
|
B
|
"
|
>24
|
22.6±0.2
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Lensing galaxy
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|
|
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Instrument
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NIRC (Keck)
|
WHT
|
NIC1/NICMOS (HST)
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|
Integration time
|
25 exp. of
60 sec each
|
5 exp., 2700 sec
total
|
2624 sec total
|
|
PSF size (arcsec)
|
0.6-0.75
|
1.4-1.5
|
|
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Pixel scale (mas/pixel)
|
|
|
43
|
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Date observed
|
1998/05/09
|
1998/05/19
1998/05/20
|
1998/04/18
|
|
Reference no.
|
[2]
|
[2]
|
[2]
|
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Redshifts
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Object
|
Redshift
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Instrument
|
Date Observed
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Reference
|
|
Source
|
2.064
|
LRIS (Keck II)
|
1998/04/21
|
[2]
|
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Notes
Possible 'dark lens'.
Probable radio-loud binary quasar.
Variability detected in the system. Variable component could not be identified.
Differing radio and optical brightness ratios.
Weaker radio component appears slightly resolved.
A is compact in optical/near IR images, B appears extended.
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References
Click here to see the CASTLES data available for this object, or here to search for references on NED. You can go to a paper's abstract on ADS by clicking its reference number.
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[1] Lensing galaxies: light or dark?, N. Jackson et al., Astron. & Astrophys., v.334, pp. L33-L36 (1998)
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[2] CLASS 0827+525: 'Dark lens' or binary radio-loud quasar?, L.V.E. Koopmans et al., Astron. & Astrophys., v.361 p. 815 (2000)
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[3] A submillimeter survey of gravitationally lensed quasars, R. Barvainis and R. Ivison, Astrophys. J. 571, pp. 712-720 (2002)
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