1652+398 (MRK 501)
Coordinates
R.A. = 16:53:52.2167, Dec. = +39:45:36.609 (2000.0)
z = 0.033663
Field of view is 10’x10′
GASP suggested stars: 1 2 4 6
Comparison stars
| Star | U | B | V | R | I |
| 1 | 14.23 (0.02) | 13.55 (0.03) | 12.61 (0.02) | 12.11 (0.02) | 11.63 (0.01) |
| 2 | 14.62 (0.02) | 14.10 (0.03) | 13.23 (0.02) | 12.79 (0.02) | 12.34 (0.01) |
| 3 | 15.98 (0.04) | 15.24 (0.02) | 14.80 (0.02) | 14.322 (0.009) | |
| 4 | 16.116 (0.045) | 16.05 (0.05) | 15.30 (0.02) | 14.96 (0.02) | 14.546 (0.004) |
| 5 | 16.27 (0.04) | 15.51 (0.02) | 15.08 (0.02) | ||
| 6 | 17.756 (0.180) | 16.82 (0.05) | 15.67 (0.04) | 14.99 (0.04) | 14.373 (0.015) |
comparison stars from Villata et al., 1998, A&AS 130, 305
U and I data of Stars 1 2 from Smith, Jannuzi & Elston, 1991, ApJS 77, 67
U and I data of Stars 3 4 6 from González-Pérez, Kidger & Martín-Luis, 2001, AJ 122, 2055
IMPORTANT: we recommend to use 7.5 arcsec for the aperture radius, which allows us to optimize the subtraction of the host galaxy contribution in the following data analysis.