Models of the strongly lensed quasar DES J0408-5354

December 2017 • 2017MNRAS.472.4038A

Authors • Agnello, A. • Lin, H. • Buckley-Geer, L. • Treu, T. • Bonvin, V. • Courbin, F. • Lemon, C. • Morishita, T. • Amara, A. • Auger, M. W. • Birrer, S. • Chan, J. • Collett, T. • More, A. • Fassnacht, C. D. • Frieman, J. • Marshall, P. J. • McMahon, R. G. • Meylan, G. • Suyu, S. H. • Castander, F. • Finley, D. • Howell, A. • Kochanek, C. • Makler, M. • Martini, P. • Morgan, N. • Nord, B. • Ostrovski, F. • Schechter, P. • Tucker, D. • Wechsler, R. • Abbott, T. M. C. • Abdalla, F. B. • Allam, S. • Benoit-Lévy, A. • Bertin, E. • Brooks, D. • Burke, D. L. • Rosell, A. Carnero • Kind, M. Carrasco • Carretero, J. • Crocce, M. • Cunha, C. E. • D'Andrea, C. B. • da Costa, L. N. • Desai, S. • Dietrich, J. P. • Eifler, T. F. • Flaugher, B. • Fosalba, P. • García-Bellido, J. • Gaztanaga, E. • Gill, M. S. • Goldstein, D. A. • Gruen, D. • Gruendl, R. A. • Gschwend, J. • Gutierrez, G. • Honscheid, K. • James, D. J. • Kuehn, K. • Kuropatkin, N. • Li, T. S. • Lima, M. • Maia, M. A. G. • March, M. • Marshall, J. L. • Melchior, P. • Menanteau, F. • Miquel, R. • Ogando, R. L. C. • Plazas, A. A. • Romer, A. K. • Sanchez, E. • Schindler, R. • Schubnell, M. • Sevilla-Noarbe, I. • Smith, M. • Smith, R. C. • Sobreira, F. • Suchyta, E. • Swanson, M. E. C. • Tarle, G. • Thomas, D. • Walker, A. R.

Abstract • We present detailed modelling of the recently discovered, quadruply lensed quasar J0408-5354, with the aim of interpreting its remarkable configuration: besides three quasar images (A,B,D) around the main deflector (G1), a fourth image (C) is significantly reddened and dimmed by a perturber (G2) which is not detected in the Dark Energy Survey imaging data. From lens models incorporating (dust-corrected) flux ratios, we find a perturber Einstein radius 0.04 arcsec ≲ R_{E, G2} ≲ 0.2 arcsec and enclosed mass M_p(R_{E, G2}) ≲ 1.0 × 10¹⁰ M_⊙. The main deflector has stellar mass log _{10}(M_{\star }/M_{⊙})=11.49^{+0.46}_{-0.32}, a projected mass M_p(R_{E, G1}) ≈ 6 × 10¹¹ M_⊙ within its Einstein radius R_{E, G1} = (1.85 ± 0.15) arcsec and predicted velocity dispersion 267-280 km s^-1. Follow-up images from a companion monitoring campaign show additional components, including a candidate second source at a redshift between the quasar and G1. Models with free perturbers, and dust-corrected and delay-corrected flux ratios, are also explored. The predicted time-delays (Δt_AB = (135.0 ± 12.6) d, Δt_BD = (21.0 ± 3.5) d) roughly agree with those measured, but better imaging is required for proper modelling and comparison. We also discuss some lessons learnt from J0408-5354 on lensed quasar finding strategies, due to its chromaticity and morphology.

Links

• SIMBAD http://simbad.u-strasbg.fr/simbo.pl?bibcode=2017MNRAS.472.4038A
• PDF http://academic.oup.com/mnras/pdf-lookup/472/4/4038
• NED https://ned.ipac.caltech.edu/uri/NED::InRefcode/2017MNRAS.472.4038A
• PREPRINT http://arxiv.org/abs/1702.00406
• ELECTR https://doi.org/10.1093%2Fmnras%2Fstx2242