FLASH Talks: Bryce Bolin (NASA GSFC) & Stacey Alberts (Steward)

Friday, 21 April 2023 noon — 1 p.m. MST

NOIRLab Headquarters | 950 North Cherry Ave., Tucson, AZ 85719

Bryce Bolin (NASA GSFC) & Stacey Alberts (Steward)

Bryce Bolin, NASA GSFC
Redness of Neptunian Trojans sheds light on early Solar System
Neptunian Trojans (NTs), trans-Neptunian objects in 1:1 mean-motion resonance with Neptune, are generally thought to have been captured from the original trans-Neptunian protoplanetary disk into co-orbital resonance with the ice giant during its outward migration. It is possible, therefore, that the color distribution of NTs is a constraint on the location of any color transition zones that may have been present in the disk. In support of this possible test, we obtained g, r, and i-band observations of 18 NTs, more than doubling the sample of NTs with known visible colors to >30 objects. Out of the combined sample, we found ~4 objects with g-i colors of >1.2 mags placing them in the very red (VR) category. We find, without taking observational selection effects into account, that the NT g-i color distribution is statistically distinct from other trans-Neptunian dynamical classes. The optical colors of Jovian Trojans and NTs are shown to be less similar than previously claimed with additional VR NTs. The presence of VR objects among the NTs may suggest that the location of the red to VR color transition zone in the protoplanetary disk was interior to ~30 au.

Stacey Alberts, Steward Observatory

From Wide to Deep, From Near to Far: MIRI Surveys in GOODS-S
JWST’s Mid-Infrared Instrument (MIRI) is providing our first highly sensitive, high resolution mid-infrared look at the distant Universe, probing in exquisite detail dust-obscured galaxy evolution and early stellar mass growth.  In this talk, I will give a sneak peak at early results from local MIRI UA-GTO team members working on our 15 pointing MIRI 5-25um mosaic and ultra-deep MIRI 7.7um parallel imaging in the GOODS-S/HUDF region.  Combined with the unmatched ancillary data, we are building a new view of the nature of dust and dust-obscured activity at cosmic noon, from the role of obscured star formation to low stellar masses to a detailed breakdown of PAH emission features to a complete census of hidden, heavily-obscured AGN and their influence during this peak in galaxy growth.   At higher redshifts, we are taking advantage of the sensitive, long-wavelength coverage of MIRI to provide a unique look at the emergence of the first quiescent galaxies at z~3-6 and of early stellar populations up to z~8, where coverage around rest 1um provides invaluable constraints on stellar mass growth.  Our uniquely rich datasets demonstrate the power of both multi-band wide and deep MIRI mosaics and the beginning of our new mid-infrared view of the Universe with JWST.