| Name: Amal George Cheriyan |
| Affiliation: Indian Institute of Space Science and Technology, Thiruvananthapuram |
| Conference ID: ASI2026_468 |
| Title: A Multiwavelength Study of RAFGL2591: Radio Jets, Ionized Regions, and Gas Kinematics in a Massive Star-Forming Environment |
| Abstract Type: Poster |
| Abstract Category: Stars, Interstellar Medium, and Astrochemistry in Milky Way |
| Author(s) and Co-Author(s) with Affiliation: A. G. Cheriyan(Indian Institute of Space Science and Technology, Thiruvananthapuram - 695547, India), S. Vig(Indian Institute of Space Science and Technology, Thiruvananthapuram - 695547, India), Veena V. S.(Max-Planck-Institut für Radioastronomie, auf dem Hügel, Bonn - 69, 53121, Germany), M. Beltran(INAF-Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, Firenze - 50125, Italy), Watson P. Varricatt(UKIRT Observatory, University of Hawaii, Institute for Astronomy, Hilo - HI 96720, USA), Arun Seshadri(Indian Institute of Space Science and Technology, Thiruvananthapuram - 695547, India) |
| Abstract: We present a multi-wavelength study of the massive star-forming region RAFGL2591, located at a distance of 3.3 kpc. The region is particularly intriguing due to its complex central environment, which harbours a cluster of protostars, H II regions, and multiple jets. To characterize the physical conditions in this region, we carried out observations in Bands 3, 4, and 5 with the GMRT. Our radio observation reveals an extended east–west protostellar jet that exhibits thermal radio emission from one lobe and non-thermal synchrotron emission in the opposing lobe. In addition, the H II regions exhibit spherical morphologies and positive spectral indices, confirming their thermal free–free nature. Complementary UKIRT H–K band spectroscopy reveals prominent molecular H₂ lines, [Fe II] emission, and CO band-head features, tracing shocked molecular gas, ionized jet-driven shocks, and warm, dense material associated with accretion disks or the inner regions of massive protostars. We further incorporate archival data from UKIDSS, Spitzer, and Herschel to probe the dust and embedded stellar sources. The dust temperatures associated with the H II regions span 20–60 K, indicating both externally heated envelopes and internally heated, evolved sources. Corresponding column densities in the range (0.6–1.6) × 10²³ cm⁻² imply the presence of dense, deeply embedded structures, indicating ongoing massive star formation. The derived masses of the H II regions lie between 31- 61 M⊙, with dynamical timescales of 0.4–1.4 Myr, consistent with relatively young, compact ionized regions. We have utilized molecular line observations from ALMA, covering multiple tracers, to study the central protostar VLA 3 using moment maps and PV diagrams. This reveals outflowing gas aligned with the radio jet direction, as well as with the loop-like features, which are also seen in the near-infrared. These kinematic signatures provide a plausible explanation for the origin of the near-infrared loops observed in the central region. |
