Constraints on Interacting Dark Energy Models from the DESI Baryon Acoustic Oscillation and DES Supernovae Data

The recent results from the first-year baryon acoustic oscillations (BAO) data released by the Dark Energy Spectroscopic Instrument (DESI), combined with cosmic microwave background (CMB) and Type Ia supernova (SN) data, have shown a detection of significant deviation from a cosmological constant for dark energy. In this work, we utilize the latest DESI BAO data in combination with the SN data from the full 5 yr observations of the Dark Energy Survey and the CMB data from the Planck satellite to explore potential interactions between dark energy and dark matter. We consider four typical forms of the interaction term Q. Our findings suggest that interacting dark energy (IDE) models with Q proportional to rho de support the presence of an interaction where dark energy decays into dark matter. Specifically, the deviation from Lambda CDM for the IDE model with Q = beta H 0 rho de reaches the 3 sigma level. These models yield a lower value of Akaike information criterion than the Lambda CDM model, indicating a preference for these IDE models based on the current observational data. For IDE models with Q proportional to rho c, the existence of interaction depends on the form of the proportionality coefficient Gamma. The IDE model with Q = beta H rho c yields beta = 0.0003 +/- 0.0011, which essentially does not support the presence of the interaction. In general, whether the observational data support the existence of interaction is closely related to the model. Our analysis helps to elucidate which type of IDE model can better explain the current observational data.