학술논문
Discovery of dusty sub-solar mass young stellar objects in NGC 346 with JWST/NIRCam
Document Type
Working Paper
Author
Jones, Olivia C.; Nally, Conor; Habel, Nolan; Lenkić, Laura; Fahrion, Katja; Hirschauer, Alec S.; Chu, Laurie E. U.; Meixner, Margaret; De Marchi, Guido; Nayak, Omnarayani; Robberto, Massimo; Sabbi, Elena; Zeidler, Peter; de Oliveira, Catarina Alves; Beck, Tracy; Biazzo, Katia; Brandl, Bernhard; Giardino, Giovanna; Jerabkova, Teresa; Keyes, Charles; Muzerolle, James; Panagia, Nino; Pontoppidan, Klaus M.; Rogers, Ciaran; Sargent, B. A.; Soderblom, David R.
Source
Subject
Language
Abstract
JWST observations of NGC 346, a star-forming region in the metal-poor Small Magellanic Cloud, reveal a substantial population of sub-solar mass young stellar objects (YSOs) with IR excess. We detected $\sim$500 YSOs and pre main sequence (PMS) stars from more than 45,000 unique sources utilizing all four NIRCam wide filters with deep, high-resolution imaging, where ongoing low-mass star formation is concentrated along dust filaments. From these observations, we construct detailed near-IR colour-magnitude diagrams with which preliminary categorizations of YSO classes are made. For the youngest, most deeply-embedded objects, JWST/NIRCam reaches over 10 magnitudes below Spitzer observations at comparable wavelengths, and two magnitudes fainter than HST for more-evolved PMS sources, corresponding to $\sim$0.1 M$_\odot$. For the first time in an extragalactic environment, we detect embedded low-mass star-formation. Furthermore, evidence of IR excess and accretion suggests that dust required for rocky planet formation is present at metallicities as low as 0.2 $Z_\odot$.
Comment: 16 pages, 2 figures, Accepted Nature Astronomy
Comment: 16 pages, 2 figures, Accepted Nature Astronomy