The study of the properties of the dust around young protostars is crucial for the understanding of how early in the star and planet formation process dust grains start to efficiently coagulate and evolve from micron sized particles to pebbles and then planetesimals. However, the physical and dust properties of the collapsing cloud material and their connection with the disk scales are still poorly understood. Recent studies have analyzed sub-mm/mm observations to probe how effective is the dust coagulation in the earliest stages of star formation, but the findings about grain sizes are still not conclusive.
In this talk I’ll present the radiative transfer modeling in Per-emb-50, a Class I protostar located in the complex NGC 1333 within the Perseus star forming region. This is the first self-consistent radiative transfer modeling of this source that constrains the disk, envelope and dust properties simultaneously by fitting multi-wavelength observations. Per-emb-50 has provided a new example which shows that only through a detailed radiative transfer modeling we can overcome the challenge of robustly disentangling the disk and envelope masses and their physical and dust properties.