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Old Q0957+561 data & software: 

Optical Monitoring

HST-STIS Spectra

Simple FORTRAN programs to apply the d2 test (accurate and robust time delay measurements)


Postgraduate Course on GL




Workshop 2004



   ► Photos






QSO 2237+0305ABCD

Old data and associated analyses

QSO 2237+0305 VR Light Curves from Gravitational LensES International Time Project Optical Monitoring (ApJ)

The Nature and Size of the Optical Continuum Source in QSO 2237+0305 (ApJ)   

Determination of the properties of the central engine in microlensed QSOs (A&A)    

Limits on the transverse velocity of the lensing galaxy in Q2237+0305 from the lack of strong microlensing variability (A&A)

Is there a caustic crossing in the lensed quasar Q2237+0305 observational data record? (MNRAS)


     New data

LT light curves in 2006-2016 (11 years with a long gap)



   New database for a sample of optically bright lensed quasars in the northern hemisphere (A&A)


Table 16: LT light curves in the r band [185 epochs in 2006-2016]

Col. 1: MJD-50000 (Modified Julian Date - 50000)
Col. 2: mA (Magnitude of QSO B2237+0305A)
Col. 3: emA (Error in magnitude of QSO B2237+0305A)
Col. 4: mB (Magnitude of QSO B2237+0305B)
Col. 5: emB (Error in magnitude of QSO B2237+0305B)  

Col. 6: mC (Magnitude of QSO B2237+0305C)
Col. 7: emC (Error in magnitude of QSO B2237+0305C)
Col. 8: mD (Magnitude of QSO B2237+0305D)
Col. 9: emD (Error in magnitude of QSO B2237+0305D)

Col. 10: mS (Magnitude of the control star S)
Col. 11: emS (Error in magnitude of S)