Discovery of a Collimated Jet from the Low-luminosity Protostar IRAS 16253‑2429 in a Quiescent Accretion Phase with the JWST

Narang, MayankMayankNarangManoj, P.P.ManojTyagi, HimanshuHimanshuTyagiWatson, Dan M.Dan M.WatsonMegeath, S. ThomasS. ThomasMegeathFederman, SamuelSamuelFedermanRubinstein, Adam E.Adam E.RubinsteinGutermuth, RobertRobertGutermuthCARATTI O GARATTI, AlessioAlessioCARATTI O GARATTIBeuther, HenrikHenrikBeutherBourke, Tyler L.Tyler L.BourkeVan Dishoeck, Ewine F.Ewine F.Van DishoeckEvans, Neal J.Neal J.EvansAnglada, GuillemGuillemAngladaOsorio, MayraMayraOsorioStanke, ThomasThomasStankeMuzerolle, JamesJamesMuzerolleLooney, Leslie W.Leslie W.LooneyYang, Yao-LunYao-LunYangKlaassen, PamelaPamelaKlaassenKarnath, NicoleNicoleKarnathAtnagulov, PrabhaniPrabhaniAtnagulovBrunken, NashantyNashantyBrunkenFischer, William J.William J.FischerFurlan, EliseEliseFurlanGreen, JoelJoelGreenHabel, NolanNolanHabelHartmann, LeeLeeHartmannLinz, HendrikHendrikLinzNazari, PoonehPoonehNazariPokhrel, RiwajRiwajPokhrelRahatgaonkar, RohanRohanRahatgaonkarRocha, Will R. M.Will R. M.RochaSheehan, PatrickPatrickSheehanSlavicinska, KaterinaKaterinaSlavicinskaStutz, Amelia M.Amelia M.StutzTobin, John J.John J.TobinTychoniec, LukaszLukaszTychoniecWolk, ScottScottWolk2025-04-142025-04-1420242041-8205http://hdl.handle.net/20.500.12386/37076Investigating Protostellar Accretion (IPA) is a JWST Cycle 1 GO program that uses NIRSpec integral field units and MIRI Medium Resolution Spectrograph to obtain 2.9–28 μm spectral cubes of young, deeply embedded protostars with luminosities of 0.2–10,000 L ⊙ and central masses of 0.15–12 M ⊙. In this Letter, we report the discovery of a highly collimated atomic jet from the Class 0 protostar IRAS 16253‑2429, the lowest-luminosity source (L bol = 0.2 L ⊙) in the IPA program. The collimated jet is detected in multiple [Fe II] lines and [Ne II], [Ni II], and H I lines but not in molecular emission. The atomic jet has a velocity of about 169 ± 15 km s‑1, after correcting for inclination. The width of the jet increases with distance from the central protostar from 23 to 60 au, corresponding to an opening angle of 2.°6 ± 0.°5. By comparing the measured flux ratios of various fine-structure lines to those predicted by simple shock models, we derive a shock speed of 54 km s‑1 and a preshock density of 2.0 × 103 cm‑3 at the base of the jet. From these quantities and using a suite of jet models and extinction laws, we compute a mass-loss rate between 0.4 and 1.1 ×10‑10 M ⊙ yr ‑1. The low mass-loss rate is consistent with simultaneous measurements of low mass accretion rate (2.4 ± 0.8 × 10‑9 M ⊙ yr‑1) for IRAS 16253‑2429 from JWST observations, indicating that the protostar is in a quiescent accretion phase. Our results demonstrate that very low-mass protostars can drive highly collimated, atomic jets, even during the quiescent phase.STAMPAenDiscovery of a Collimated Jet from the Low-luminosity Protostar IRAS 16253‑2429 in a Quiescent Accretion Phase with the JWSTArticle10.3847/2041-8213/ad1de32-s2.0-85184889449https://iopscience.iop.org/article/10.3847/2041-8213/ad1de3https://api.elsevier.com/content/abstract/scopus_id/851848894492024ApJ...962L..16NFIS/05 - ASTRONOMIA E ASTROFISICA