Tension in the Recent Type Ia Supernovae Datasets

TL;DR

This paper examines inconsistencies among recent Type Ia supernovae datasets and identifies sources of tension with other cosmological observations, proposing truncated datasets to improve data reliability.

Contribution

It systematically analyzes dataset tensions and introduces truncated versions to enhance consistency in cosmological analyses.

Findings

Identified tensions between SNIa datasets and CMB/BAO observations.

Pinpointed main sources of dataset inconsistencies.

Proposed truncated datasets with more regular behavior.

Abstract

In the present work, we investigate the tension in the recent Type Ia supernovae (SNIa) datasets Constitution and Union. We show that they are in tension not only with the observations of the cosmic microwave background (CMB) anisotropy and the baryon acoustic oscillations (BAO), but also with other SNIa datasets such as Davis and SNLS. Then, we find the main sources responsible for the tension. Further, we make this more robust by employing the method of random truncation. Based on the results of this work, we suggest two truncated versions of the Union and Constitution datasets, namely the UnionT and ConstitutionT SNIa samples, whose behaviors are more regular.