A set of synthetic spectral energy distributions for "diskless", intermediate-mass young stars

These models were published in conjunction with The Duration of Star Formation in Galactic Giant Molecular Clouds. I. The Great Nebula in Carina, by Povich et al. (2019). They will also be used in subsequent papers in that series.

The format of these models conforms with the standards of Robitaille (2017), so they are compatible with the python implementation of the Robitaille et al. (2007) SED fitting tool. We have pre-convolved these models with a number of useful filters, including Johnson/Bessel UBVRI, UKIRT ZYJHK, VISTA ZYJHK_S, 2MASS JHK_S, Spitzer/IRAC and MIPS. 

A software pipeline implementing these models to constrain the age and mass distributions of young stellar populations is also publicly available.

Limitations of these models

These models produce the best results for stars more massive than the Sun and older than about 0.5 Myr. They employ the pre-main-sequence evolutionary tracks of Siess et al. (2000) and Bernasconi & Maeder (1996). Numerous modern tracks offer significant improvement in the treatment of subsolar-mass stars. In addition, the Kurucz stellar atmospheres used in these synthetic SEDs work best for T_eff > 4,000 K; for cooler temperatures other models, for example the PHOENIX photospheres, may be more appropriate.

Newer evolutionary tracks covering the intermediate-mass range are now available, for example the Geneva pre-MS tracks of Haemmerlé et al. (2019). The principal innovation of these modern models is the treatment of accretion and location of the intermediate-mass stellar birthline. The coolest, most luminous models in this set are likely unphysical, representing fully-convective stars of  >2 solar masses and <0.5 Myr isochronal age.