Blowing star formation away in AGN Hosts (BAH) -- IV: Feeding and feedback in 3C 293 observed with JWST NIRSpec

Maitê S. Z. de Mellos, Rogemar A. Riffel, Gabriel L. Souza-Oliveira, Nadia L. Zakamska, Marina Bianchin, Thaisa Storchi-Bergmann, Rogério Riffel, José Henrique Costa-Souza

First listed 2025-06-26 | Last updated 2025-11-11

Abstract

We use JWST/NIRSpec observations of the radio galaxy 3C 293 to map the emission, extinction, and kinematics of hot molecular and ionized gas, as well as stellar kinematics, within the inner ~ 2 kpc. The stellar velocity field is well described by a rotating disk model, with its kinematical center offset by ~ 0.5 arcsec from the continuum peak. The hot molecular gas is traced by the H$_2$2.12$μ$m emission line, and the ionized gas by [Fe II]1.64$μ$m and Pa$α$. The gas presents three main kinematic components: a rotating disk seen as a narrow component ($σ$ ~ 100 kms$^{-1}$); a blueshifted broad outflow ($σ$ ~ 250 kms$^{-1}$); and a fast ionized outflow as a very broad component ($σ$ ~ 640 kms$^{-1}$). Extinction maps reveal high A$_V$ values, up to ~ 35, spatially coincident with dust lanes seen in optical images. In addition to the disk and outflows components, inflows along the dust lanes are detected in H$_2$ gas, with a mass inflow rate of $\dot{M}_{in}$ ~ 4 x 10$^{-4}$ M$_{\odot}$ yr$^{-1}$, which is lower than the AGN accretion rate. For the outflows, we derive peak mass-outflow rates of 0.08 $\pm$ 0.02 M$_{\odot}$yr$^{-1}$ (molecular) and 6.5 $\pm$ 1.7 M$_{\odot}$yr$^{-1}$ (ionized). The outflow, driven by the radio jet, has a kinetic power of 5.7% of the jet power - enough to suppress star formation. Our results highlight 3C 293's turbulent post-merger history and JWST's unique capability to probe dust-obscured AGN.

Short digest

JWST/NIRSpec IFU mapping of 3C 293’s inner ~2 kpc separates the gas into a rotating disk (σ ~100 km s−1), a blueshifted broad outflow (σ ~250 km s−1), and a very broad ionized outflow (σ ~640 km s−1). H2 2.12 μm, [Fe II] 1.64 μm, and Paα trace multiphase flows through heavy dust (A_V up to ~35), with H2 inflow along dust lanes at Ṁ_in ~4×10−4 M⊙ yr−1. Peak outflow rates reach 0.08±0.02 M⊙ yr−1 (hot H2) and 6.5±1.7 M⊙ yr−1 (ionized), and the jet-driven outflow carries ≈5% of the radio-jet power—sufficient to suppress star formation. The stellar field is a rotating disk whose kinematic center is offset by ~0.5 arcsec from the NIR continuum peak, consistent with a disturbed, post-merger nucleus.

Key figures to inspect

• Fig. 1 composite + nuclear spectrum: verify strong H2, [Fe II], and Paα features and CO bandheads at the continuum peak; use to see the emission-line budget that motivates the multiphase kinematic decomposition.
• Fig. 2 line-profile fits ([Fe II], Paα, H2): inspect the narrow/broad/very broad components and their σ values (~100/250/640 km s−1) and blueshifts, clarifying which phases host the fast outflow.
• Fig. 3 stellar velocity/dispersion maps: confirm the rotating stellar disk and measure the ~0.5 arcsec offset between the kinematic center and continuum peak; check for central σ enhancements indicative of a disturbed nucleus.
• Fig. 4 gas maps (flux/velocity/dispersion): compare narrow vs broad components to locate the jet-aligned outflow and identify H2 streaming along dust lanes (inflow) versus outflowing ionized gas, and relate high-velocity regions to obscured structures.