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Although the IceCube geometry has been optimized to detect ultra-high energy ( > TeV) neutrinos from poten- tial cosmic sources with sub-degree angular resolution, its angular response is still adequate at O (100 GeV) to perform directional searches for dark matter. IceCube has recently published results on the searches for WIMPs arising in the MSSM [17] or the simplest UED model [18] using 22 strings deployed in the 2006/2007 Antarctic sea- son. In this work we use this 22-string detector (hereafter referred to as IceCube-22) which took data during the 2007 austral winter. We set a limit in the simpzilla mass, m$_{X}$, versus simpzilla-nucleon cross section, σ$_{XN}$ , phase space using the fact that IceCube-22 has not detected any neutrino excess from the direction of the Sun. We also estimate the sensitivity of the full IceCube detector in its expected final configuration with 86 strings (here- after referred to as IceCube-86). 

## II. NEUTRINO SPECTRUM FROM SIMPZILLA ANNIHILATIONS 

In order to estimate the neutrino rate from simpzilla annihilations in the Sun, we use the capture rate, as well as the full-flavour neutrino flux and energy spectrum at the core of the Sun as determined in [6]. We then simulate the neutrino propagation to the Earth, including energy losses and oscillation effects. 

The capture rate, Γ$_{c}$, depends on the mass of the sim- pzilla, m$_{X}$, and the strength of the interaction of sim- pzillas with nucleons, σ$_{XN}$ . The capture efficiency can be described by the parameter q = m$_{X}$ m$_{N}$ n$_{N}$ σ$_{XN}$$_{R$_{⊙}$}$, where m$_{N}$ 

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is the average nucleon mass, n$_{N}$ is the number density of nucleons in the Sun and R ⊙ is the radius of the Sun. For large cross sections, q ≤ 1, and simpzillas lose enough energy in their passage through the Sun to be efficiently captured. The capture rate (in s − $^{1}$) is then given by 

On the other hand, if q > 1, capture is determined by the relative velocity, and only low velocity simpzillas are trapped. In such case, the capture rate is 

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where in the above expressions 

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and u$_{th}$ is the speed of the Sun in the galaxy and v ⊙ is the Sun escape velocity. Note that if σ$_{XN}$ goes to zero, then the capture rate goes to zero through its dependency on x , as it is expected. 

The simpzilla capture rate is large enough to reach equilibrium with the annihilation rate, Γ$_{A}$, in the life- time of the solar system, and therefore we can as- sume Γ$_{A}$ = Γ$_{c}$ / 2. 

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