work are 3.5 fm and 268 MeV/c, respectively.

Results and Discussions
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The neutron-to-proton ratio is among the first observables that was proposed as a possible sensitive probe for symmetry energy prediction at sub-saturation densities [@Li97; @Zhan08]; however, some studies are also performed using the rapidity distribution and transverse momentum dependencies at supra-saturation densities. In this article, the sensitivities of free nucleons, light charged particles (LCPs, having charge number between 1 and 2), and intermediate mass fragments (IMFs, having charge number between 3 and $Z_{Total}/6$) to the high density behavior of symmetry energy are checked, providing the results of incident energy and isospin asymmetry dependencies of single and double neutron-to-proton ratios with the high-density sensitive fragments.

To perform the study, thousand of events are simulated for the isotopes of Sn, namely $^{112}$Sn + $^{112}$Sn, $^{124}$Sn + $^{124}$Sn and $^{132}$Sn + $^{132}$Sn between incident energies of 50 and 600 MeV/nucleon at semicentral geometry by using the soft and stiff symmetry energies of $\gamma_i~=~0.5$ and 1.5, respectively. As discussed earlier, a soft equation of state with an isospin- dependent nucleon-nucleon (NN) cross section of $\sigma_{med}~=~\left(1-0.2\frac{\rho}{\rho_0}\right)\sigma_{free}$ is employed. The incident energy and isospin asymmetry dependences of single and double neutron-to-proton ratios, just as 