Establish whether silicate crystallization occurred in situ

Establish whether the crystalline-silicate emission observed during the PR Ori B outburst was produced in situ during the outburst or originated from pre-existing crystalline silicates in the circumstellar disk.

Background

The comparison between quiescent Spitzer/IRS and outburst VLT/VISIR spectra reveals features attributed to crystalline forsterite and possibly quartz. These observations suggest that the increased luminosity may have heated dust and generated crystalline material in the inner disk.

However, the available data do not extend to wavelengths longer than 16 microns, which the authors identify as necessary for distinguishing newly formed crystals from pre-existing crystalline silicates. Future JWST observations are proposed as a way to resolve this uncertainty.

References

We do not have data at longer wavelengths to discard whether the emission originated from pre-existing crystalline silicates \citep[observations at $\lambda>16\,\mu$m are used as evidence in][]{2009Abraham,2026Lee}. Future JWST observations could help to confirm that we are observing in-situ formation of crystals in the outburst of PR Ori B.

— The FU Ori outburst of PR Ori B  (2609.09722 - Pena et al., 9 Sep 2026) in Section 6.3, “Evidence of silicate crystallization during the outburst”