Figure 1: Dark matter distribution in the galaxy cluster MACSJ1206 reconstructed from combined strong and weak lensing analysis (Umetsu et al. 2012).

Figure 2: Ensemble averaged density profile of dark matter in CLASH galaxy clusters (Umetsu et al. 2016).

The results obtained here are generally favorable in terms of the standard explanation for dark matter as effectively cold and collisionless, with an excellent match between lensing data and CDM predictions for high-mass clusters. These studies represent a first step toward using cluster gravitational lensing to examine detailed predictions from cosmological simulations regarding the structure and shape of dark-matter halos. Such predictions can be unambiguously tested across a wide range of cluster masses and redshifts, with large statistical samples of clusters from ongoing and planned lensing surveys such as the Subar Hyper Suprime-Cam survey, the XXL survey, the eROSITA, WFIRST, and Euclid missions.

References
Bertschinger 1985, ApJS, 58, 39
Clowe et al. 2004, ApJ, 604, 596
Diemer & Kravtsov 2014, ApJ, 789, 1
Fillmore & Goldreich 1984, ApJ, 281, 1
Gunn & Gott 1972, ApJ, 176, 1
Navarro, Frenk, & White 1997, ApJ, 490, 493
Okumura, Nishimichi, Umetsu, & Osato 2018,
Postman et al. 2012, ApJS, 199, 25
Randall et al. 2008, ApJ, 679, 1173
Schive et al. 2014, Nature Physics, 10, 496
Spergel & Steinhardt 2000, PRL, 84, 3760
Umetsu 2010, arXiv: 1002.3952
Umetsu et al. 2012, ApJ, 755, 56
Umetsu et al. 2014, ApJ, 795, 163
Umetsu et al. 2015, ApJ, 806, 207
Umetsu et al. 2016, ApJ, 821, 116
Umetsu & Diemer 2017, ApJ, 836, 231
Umetsu et al. 2018, ApJ, 860, 104
Watson et al. 2014, MNRAS, 437, 3776