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CLASS B1127+385, a double image gravitational lens



Lens System Summary

B1127+385 is a double-image gravitational lens system. There are two lensing galaxies; the primary is between images A and B (but closer to A). In the infrared (H-band) the source appears as a near - Einstein ring. No redshifts are yet known for this system. This lens is not part of the statistically complete CLASS sample because it is too faint at 5GHz.

This Lens System

Lens name B1127+385
Survey CLASS
Images 2
B1950.0 coords 11h27m19.145s 38°28'35.770"
J2000.0 coords 11h30m00.099s 38°12'03.091"

Lens System Structure and Labelling

Image labelling for this lens (RA increases to the left, declination increases upwards)

Images labelled as in Koopmans et al. Galaxies labelled as in Koopmans et al.

Image/Lens Positions

Image/Lens Relative Position
East (mas) North (mas)
A 0.0±2 0.0±2
A1 0.0±0.1 0.0±0.1
A2 0.6±0.1 2.1±0.1
B 685±2 138±2
B1 686.6±0.1 140.1±0.1
B2 687.0±0.1 139.2±0.1

Image/Lens Separations

Separation (mas)
Component A A1 A2 B B1 B2
A
0.0 2.2 698.8 700.7 701.0
A1 0.0
2.2 698.8 700.7 701.0
A2 2.2 2.2
697.8 699.7 700.0
B 698.8 698.8 697.8
2.6 2.3
B1 700.7 700.7 699.7 2.6
1.0
B2 701.0 701.0 700.0 2.3 1.0
Position angle (°)
Component A A1 A2 B B1 B2
A
0.0 -164.1 -101.4 -101.5 -101.5
A1 0.0
-164.1 -101.4 -101.5 -101.5
A2 15.9 15.9
-101.2 -101.4 -101.3
B 78.6 78.6 78.8
-142.7 -121.0
B1 78.5 78.5 78.6 37.3
-24.0
B2 78.5 78.5 78.7 59.0 156.0

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.

Optical and IR images Click to see a larger version
WFPC2 V-band image
Koopmans et al. 		Click to see a larger version
WFPC2 r-band image
Koopmans et al. 		Click to see a larger version
WFPC2 I-band image
Koopmans et al. 		Click to see a larger version
WHT image
Radio maps
(VLA and MERLIN) 		Click to see a larger version
MERLIN 5GHz image 		Click to see a larger version
VLA 8.4GHz image
Koopmans et al.
Radio maps (VLBA) Click to see a larger version
Comp. A, VLBA X-band image
Koopmans et al. 		Click to see a larger version
Comp. B, VLBA X-band image
Koopmans et al.

Radio Flux Densities

Component Flux density (mJy)
1.7 GHz 5 GHz 8.4 GHz 8.4 GHz
A 16.0 15.3 14.7
A1


10.5
A2


3.2
B 14.0 11.5 11.8
B1


7.9
B2


2.9
Flux errors 10% 10% 10% 10%
Resolution (mas) 60 60 200 1.7
Map noise level
(mJy/beam)



Instrument MERLIN MERLIN VLA VLBA
Date observed 1996/02/13 1996/12 1995/08/14 1996/11/04
Reference [1] [1] [1] [1]

Sub-millimetre Flux Densities

Component Flux density (mJy)
1300 μm 850 μm 450 μm
Total <2.8 13.9±2.3 <65
Estimated
cal. error
5-10% 5-10%
Instrument IRAM 30-m SCUBA (JCMT) SCUBA (JCMT)
Date observed
1999-2001 1999-2001
Reference [2] [2] [2]

Optical Imaging

Component Brightness (Magnitudes)
F555W (V) F814W (I)
G1 22.5±0.1 24.4±0.2
G2 23.5±0.1 25.5±0.2
Instrument WFPC2 (HST) WFPC2 (HST)
Integration time 700s + 300s 2 exp. of
500s each
PSF size (arcsec)

Pixel scale (mas/pixel) 45.5 45.5
Date observed 1996/06/21 1996/06/21
Reference no. [1] [1]

Lens Models

Click on the model's reference number to go to the relevant paper's abstract on ADS.


[1] Koopmans et al. find that an acceptable mass model should include both G1 and G2. Such a model (using an SIE for G1 and SIS for G2) fits both radio and optical data with a reduced Χ2 of 1.1.

Notes

  1. Redshifts for this system are currently unknown.

  2. Variability monitoring has been conducted using WSRT.

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.


[1] A new radio double lens from CLASS: B1127+385, L. V. E. Koopmans et al., Mon. Not. R. Astron. Soc. 303, Issue 4, pp. 727-735. (1999)


[2] A submillimeter survey of gravitationally lensed quasars, R. Barvainis and R. Ivison, Astrophys. J. 571, pp. 712-720 (2002)

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