... MS 2137.3-2353[*]
Based on observations obtained at the Very Large Telescope (VLT) at Cerro Paranal operated by European Southern Observatory. 
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... F702W filter[*]
Program ID: 5402; PI: Gioia. 
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...K[*]
Program ID: 67.A-0098(A) FORS and 67.A-0098(B) ISAAC; PI: Mellier. 
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... center[*]
http://terapix.iap.fr 
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... ellipticity[*]
All ellipticities discussed here are defined as $\epsilon={a^2-b^2 \over a^2+b^2}$, where a and b are the major and minor axes. 
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... elliptical[*]
We used the task ellipse in the IRAF/STSDAS package for isophotal fitting. 
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... lensmodel[*]
http://astro.uchicago.edu/~ckeeton/gravlens/ 
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... times[*]
Equation (10): the -2 in parenthesis includes the unknown source position and the unused fifth central image. When using this later, the number of constraints is 156. 
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... profile[*]
These values are higher than 1 but we remind that the models are significantly over-constrained. 
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... potential[*]
Leading to a convergence: $\kappa(r) = \frac{b}{r_{\rm c}}\frac{2+x^2}{(1+x^2)^{3/2}}$ with $x=r/r_{\rm c}$ to be compared to Eq. (12). 
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... shape[*]
After subtraction of the cluster population. 
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...$u\approx 1.85\hbox{$^{\prime\prime}$ }$[*]
Few variations are observed when modeling with the NFW or the IS model. We also neglect ellipticity terms which have a weak importance near the center. 
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... efficiency[*]
The $\zeta$-statistic S/N ratio at radius r goes like $\ln r_{\rm max}/r$ for an isothermal profile. 
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...1998)[*]
See references therein for a list of analogous objects. 
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...$\Delta A5_{\rm r}=0.5\hbox{$^{\prime\prime}$ },\Delta A5_{\rm t}=0.8\hbox{$^{\prime\prime}$ }$)[*]
Note that the ellipticity of the mass distribution implies that the magnification matrix is not diagonal. Hence, the radial and tangential lengths correspond to the radial arc length. 
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Copyright ESO 2003