-28 -27 -26 -25 -24 -23 -22 -21 -20 4 6 8 10 12 14 log M$_{X}$ (GeV) log  $_{σ}$XN  (cm 2 ) Direct Mine/Space Earth heat IceCube-22 IceCube-86 (sens.) posed to weak as in the case of WIMPs. However for experimental searches such distinction is important be- cause different experiments probe different components of the cross section. The results from the experiments shown in Figure 1 refer mainly to the spin-independent component of the simpzilla-nucleon cross section, due to the nature of the targets involved or, in the case of the Earth heat flow analysis, due to the fact that the capture of dark matter candidates in the Earth proceeds mainly through scattering on spinless nuclei (Fe, Si, O, Mg). On the other hand the IceCube results are sensitive to the spin-dependent cross section since the Sun is the target for capture, which is essentially a proton target. In view of the previous considerations, the current re- sults from IceCube provide the most restrictive limits so far on the spin-dependent cross section of simpzillas. The fact that they overlap in the (m$_{X}$, σ$_{XN}$ ) parameter space with previous exclusion regions from experiments which probe mainly the spin-independent cross section, practically rules out simpzillas as dark matter. It would require an unreasonably narrow fine tuning of the mass and the structure of the cross section to propose a viable candidate that would evade all the current limits. In conclusion, strongly interacting heavy relics from the early Universe can only account for the dark matter if they have masses above 10 15 GeV. As these ultra heavy masses are not currently favored by any model, the window for simpzillas as the only component of dark matter can be considered closed. searches is due at this point. Generally, the total cross section with nucleons, σ$_{XN}$ , can have at least two contri- butions, a spin-independent (or scalar) component and a spin-dependent (or axial-vector) component, the rel- ative strength of each depending on the exact assump- tions made on the structure and interaction of the sim- pzilla. There is no detailed modelling in the literature of the way that simpzillas interact with matter, other than the interaction is assumed to be “strong”, as op- Acknowledgments: We thank T. Sj¨ ostrand for his kind help with Pythia . IA was partially funded by the U.S. Department of Energy under contract number DE-AC02- 07CH11359 and the Brazilian National Counsel for Sci- entific Research (CNPq) FIG. 6: Dis fav oured region in the (m X , σ XN ) parameter space at 90% con fide nce level from IceCube-22 (red cross–hatched area), overl aye d with results from previous experiments: di- rect search es [9 ] (solid yellow area), space-borne detectors [7] (blue squar e–h atched area) and Earth heat flow analysis [10] (green striped area). The black line represents the 1 year expected sensitivity of the completed IceCube detector. 5 [22] R. Abassi et al . Phys. Rev. D79 ,102005 (2009). [10] G. D. Mack, J. F. Beacom and G. Bertone, Phys. Rev. D76 , 043523 (2007). [9] I. F. M. Albuquerque and L. Baudis, Phys. Rev. Lett. 90 , 221301 (2003). [8] G. D. Starkman, A. Gould, R. Esmailzadeh and S. Di- mopoulos, Phys. Rev. D 41 , 3594 (1990). [7] P. C. McGuire and P. J. Steinhardt. Proceed- ings of the 27th International Cosmic Ray Confer- ences (ICRC 2001), Hamburg, Germany, Aug 2001. astro-ph/0105567 . [6] I. F. M. Albuquerque, L. Hui and E. W. Kolb. Phys. Rev. D64 , 083504 (2001). [5] D. J. H Chung, E. W. Kolb and A. Riotto. Phys. Rev. Lett. 81 , 4048 (1998). [4] D. J. H Chung, E. W. Kolb and A. Riotto. Phys. Rev. D60 , 063504 (1999). [3] D. J. H Chung, E. W. Kolb and A. Riotto. Phys. Rev. D59 , 023501 (1998). [2] D. Hooper and S. Profumo. Phys. Rep. 453 , 29 (2007). [1] K. Griest and M. Kamionkowski. Phys. Rev. Lett. 64 , 615 (1990). [21] W. A. Rolke, A M. L´ opez and J. Conrad. Nucl. Instrum. Meth. A551 , 493-503 (2005). [20] J. Edsj¨ o, WimpSim Neutrino Monte Carlo, http://www.physto.se/˜edsjo/wimpsim/ [19] T. Sj¨ ostrand, S. Mrenna and P. Skands, JHEP05, 025, (2006) http://home.thep.lu.se/˜torbjorn/Pythia.html. [18] R. Abassi et al . arXiv:0910.4480. [17] R. Abassi et al . Phys. Rev. Lett. 102 , 201302 (2009). [16] C. Wiebusch et al . Proceedings of the 31st International Cosmic Ray Conferences (ICRC 2009), Lodz, Poland, July 2009. arXiv:0907.2263 . [15] J. Ahrens et al . Astropart. Phys. 20 , 507, (2004) [14] I. F. M. Albuquerque, J. Lamoureux and G. F. Smoot, Phys. Rev. D66 , 125006 (2002). [13] A. Gould. Ap. J. 328 , 919 (1988). [12] T. K. Gaisser, G. Steigman and S. Tilav. Phys. Rev. D34 , 2206 (1986). [11] W. H. Press and D. N. Spergel. Astrophys. J. 296 , 769 (1985);