Testing Cosmological Models with Type Ic Super Luminous Supernovae

The use of type Ic Super Luminous Supernovae (SLSN Ic) to examine the cosmological expansion introduces a new standard ruler with which to test theoretical models. The sample suitable for this kind of work now includes 11 SLSN Ic’s, which have thus far been used solely in tests involving ΛCDM. In this paper, we broaden the base of support for this new, important cosmic probe by using these observations to carry out a one-on-one comparison between the Rh = ct and ΛCDM cosmologies. We individually optimize the parameters in each cosmological model by minimizing the χ statistic. We also carry out Monte Carlo simulations based on these current SLSN Ic measurements to estimate how large the sample would have to be in order to rule out either model at a ∼ 99.7% confidence level. The currently available sample indicates a likelihood of ∼70− 80% that the Rh = ct Universe is the correct cosmology versus ∼20 − 30% for the standard model. These results are suggestive, though not yet compelling, given the current limited number of SLSN Ic’s. We find that if the real cosmology is ΛCDM, a sample of ∼240 SLSN Ic’s would be sufficient to rule out Rh = ct at this level of confidence, while ∼480 SLSN Ic’s would be required to rule out ΛCDM if the real Universe is instead Rh = ct. This difference in required sample size reflects the greater number of free parameters available to fit the data with ΛCDM. If such SLSN Ic’s are commonly detected in the future, they could be a powerful tool for constraining the dark-energy equation of state in ΛCDM, and differentiating between this model and the Rh = ct Universe. Subject headings: cosmic background radiation – cosmological parameters – cosmology: observations – cosmology: theory – distance scale – supernovae: general