[en] The light travel time differences in strong gravitational lensing systems allows an independent determination of the Hubble constant. This method has been successfully applied to several lens systems. The formally most precise measurements are, however, in tension with the recent determination of H[SUB]0[/SUB] from the Planck satellite for a spatially flat six-parameters ΛCDM cosmology. We reconsider the uncertainties of the method, concerning the mass profile of the lens galaxies, and show that the formal precision relies on the assumption that the mass profile is a perfect power law. Simple analytical arguments and numerical experiments reveal that mass-sheet like transformations yield significant freedom in choosing the mass profile, even when exquisite Einstein rings are observed. Furthermore, the characterization of the environment of the lens does not break that degeneracy which is not physically linked to extrinsic convergence. We present an illustrative example where the multiple imaging properties of a composite (baryons + dark matter) lens can be extremely well reproduced by a power-law model having the same velocity dispersion, but with predictions for the Hubble constant that deviate by ~20%. Hence we conclude that the impact of degeneracies between parametrized models have been underestimated in current H[SUB]0[/SUB] measurements from lensing, and need to be carefully reconsidered.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Schneider, Peter; Argelander-Institut für Astronomie, Universität Bonn, Auf dem Hügel 71, 53121, Bonn, Germany
Sluse, Dominique ; Universität Bonn > Argelander-Institut für Astronomie
Language :
English
Title :
Mass-sheet degeneracy, power-law models and external convergence: Impact on the determination of the Hubble constant from gravitational lensing
Dutton, A. A., & Treu, T. 2013, MNRAS, submitted [arXiv:1303.4389]
Dutton, A. A., Brewer, B. J., Marshall, P. J., et al. 2011, MNRAS, 417, 1621
Eigenbrod, A., Courbin, F., Dye, S., et al. 2006, A&A, 451, 747
Eulaers, E., & Magain, P. 2011, A&A, 536, A44
Eulaers, E., Tewes, M., Magain, P., et al. 2013, A&A, 553, A121
Fadely, R., Keeton, C. R., Nakajima, R., & Bernstein, G. M. 2010, ApJ, 711, 246
Falco, E. E., Gorenstein, M. V., & Shapiro, I. I. 1985, ApJ, 289, L1
Fohlmeister, J., Kochanek, C. S., Falco, E. E., et al. 2013, ApJ, 764, 186
Gavazzi, R., Treu, T., Rhodes, J. D., et al. 2007, ApJ, 667, 176
Gavazzi, R., Treu, T., Koopmans, L. V. E., et al. 2008, ApJ, 677, 1046
Gorenstein, M. V., Shapiro, I. I., & Falco, E. E. 1988, ApJ, 327, 693
Grogin, N. A., & Narayan, R. 1996, ApJ, 464, 92
Hernquist, L. 1990, ApJ, 356, 359
Humphrey, P. J., & Buote, D. A. 2010, MNRAS, 403, 2143
Keeton, C. R. 2001 [arXiv:astro-ph/0102340]
Keeton, C. R., & Kochanek, C. S. 1998, ApJ, 495, 157
Kochanek, C. S. 2002, ApJ, 578, 25
Kochanek, C. S., Keeton, C. R., & McLeod, B. A. 2001, ApJ, 547, 50
Kochanek, C. S., Schneider, P., & Wambsganss, J. 2004, Part 2 of Gravitational Lensing: Strong, Weak & Micro, Proc. 33rd Saas-Fee Advanced Course, eds. G. Meylan, P. Jetzer, & P. North (Berlin: Springer-Verlag)
Koopmans, L. V. E. 2004 [arXiv:astro-ph/0412596]
Koopmans, L. V. E., Bolton, A., Treu, T., et al. 2009, ApJ, 703, L51
Kundic, T., Turner, E. L., Colley, W. N., et al. 1997, ApJ, 482, 75
Liesenborgs, J., & De Rijcke, S. 2012, MNRAS, 425, 1772
Liesenborgs, J., De Rijcke, S., Dejonghe, H., & Bekaert, P. 2009, MNRAS, 397, 341
Navarro, J. F., Frenk, C. S., & White, S. D. M. 1996, ApJ, 462, 563
Oguri, M., Schrabback, T., Jullo, E., et al. 2013, MNRAS, 429, 482
Padmanabhan, N., Seljak, U., Strauss, M. A., et al. 2004, New Astron., 9, 329
Remus, R.-S., Burkert, A., Dolag, K., et al. 2013, ApJ, 766, 71
Romanowsky, A. J., & Kochanek, C. S. 1999, ApJ, 516, 18
Rusin, D., & Kochanek, C. S. 2005, ApJ, 623, 666
Rusin, D., Kochanek, C. S., & Keeton, C. R. 2003, ApJ, 595, 29
Saha, P. 2000, AJ, 120, 1654
Saha, P., & Williams, L. L. R. 2004, AJ, 127, 2604
Saha, P., Coles, J., Macciò, A. V., & Williams, L. L. R. 2006, ApJ, 650, L17
Scannapieco, C., Wadepuhl, M., Parry, O. H., et al. 2012, MNRAS, 423, 1726
Schneider, P., & Seitz, C. 1995, A&A, 294, 411
Schneider, P., Ehlers, J., & Falco, E. E. 1992, Gravitational Lenses, XIV (Berlin, Heidelberg, New York: Springer-Verlag, Also Astronomy and Astrophysics Library)
Sluse, D., Courbin, F., Eigenbrod, A., & Meylan, G. 2008, A&A, 492, L39
Sluse, D., Chantry, V., Magain, P., Courbin, F., & Meylan, G. 2012, A&A, 538, A99
Sonnenfeld, A., Treu, T., Gavazzi, R., et al. 2012, ApJ, 752, 163
Suyu, S. H. 2012, MNRAS, 426, 868
Suyu, S. H., & Blandford, R. D. 2006, MNRAS, 366, 39
Suyu, S. H., & Halkola, A. 2010, A&A, 524, A94
Suyu, S. H., Marshall, P. J., Auger, M. W., et al. 2010, ApJ, 711, 201
Suyu, S. H., Auger, M. W., Hilbert, S., et al. 2013a, ApJ, 766, 70
Suyu, S. H., Treu, T., Hilbert, S., et al. 2013b, ApJL, submitted [arXiv:1306.4732]
Tewes, M., Courbin, F., Meylan, G., et al. 2013, A&A, 556, A22
Treu, T., & Koopmans, L. V. E. 2002, ApJ, 575, 87
van de Ven, G., Mandelbaum, R., & Keeton, C. R. 2009, MNRAS, 398, 607
Walsh, D., Carswell, R. F., & Weymann, R. J. 1979, Nature, 279, 381
Witt, H. J., Mao, S., & Schechter, P. L. 1995, ApJ, 443, 18
Witt, H. J., Mao, S., & Keeton, C. R. 2000, ApJ, 544, 98
Wucknitz, O. 2002, MNRAS, 332, 951
Wucknitz, O., Biggs, A. D., & Browne, I. W. A. 2004, MNRAS, 349, 14