Tidal Disruption Flares as the Source of Ultra-high Energy Cosmic Rays

TL;DR

This paper suggests that tidal disruption flares, modeled as thin accretion disks around supermassive black holes, could be the source of ultra-high energy cosmic rays, supported by spectral fits and luminosity estimates.

Contribution

It provides the first detailed spectral energy distribution modeling of TDFs and links their luminosities to UHECR acceleration potential.

Findings

TDFs' SEDs fit thin accretion disk models

Inferred luminosities exceed UHECR acceleration thresholds

Supports TDFs as potential UHECR sources

Abstract

The optical spectral energy distributions of two tidal disruption flares identified by van Velzen et al. (2011) in archival SDSS data, are found to be well-fit by a thin-accretion-disk model. Furthermore, the inferred Supermassive Black Hole mass values agree well with the SMBH masses estimated from the host galaxy properties. Integrating the model SEDs to include shorter wavelength contributions provides an estimate of the bolometric luminosities of the accretion disks. The resultant bolometric luminosities are well in excess of the minimum required for accelerating UHECR protons. In combination with the recent observational estimate of the TDF rate (van Velzen and Farrar, these Proceedings), the results presented here strengthen the case that transient jets formed in tidal disruption events may be responsible for accelerating all or most UHECRs.