How Do The AGN Feedback Mechanisms In Seyfert Galaxies With Pseudobulges And Low-mass Black Holes Influence The Metallicity Gradients Of Newly Formed Stars In The Outer Disk Regions, Particularly In The Context Of Galaxy Mergers And Gas-rich Interactions?

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In Seyfert galaxies with pseudobulges and low-mass black holes, the interplay between AGN feedback, star formation, and galaxy mergers significantly influences metallicity gradients in the outer disk regions. Here's a structured summary of the effects:

  1. AGN Feedback and Metallicity:

    • Mechanisms: AGN feedback can suppress star formation by heating or expelling gas, potentially reducing metal production in outer disks. However, weaker feedback from low-mass black holes may allow some star formation, influencing metallicity differently.
    • Outer Disk Effects: Suppressed star formation in outer regions can lead to lower metallicity, resulting in steeper metallicity gradients as the outer regions remain less enriched compared to inner areas.

  2. Impact of Galaxy Mergers:

    • Gas Inflow: Mergers introduce gas, which can be metal-poor, potentially diluting metallicity in outer regions.
    • Star Formation: AGN feedback may quench starbursts triggered by mergers, preventing metal enrichment. Conversely, if star formation proceeds, outer regions might experience metallicity increases, flattening gradients.

  3. Interplay and Timescales:

    • Episodic Feedback: AGN activity can be intermittent, allowing initial starbursts post-merger, followed by suppression, affecting metallicity gradients based on the timing and strength of feedback.
    • Transport of Metals: Efficient transport of metals from inner to outer regions might be disrupted by AGN feedback, maintaining or steepening gradients.

  4. Conclusion:

    • AGN feedback in these galaxies likely leads to steeper metallicity gradients by reducing outer disk star formation.
    • Mergers complicate this by introducing gas, which can either lower metallicity if feedback is strong or allow some metal enrichment if feedback is weaker.

Overall, the metallicity gradients in outer disks are shaped by the balance between AGN feedback suppressing star formation and mergers introducing new gas, with the outcome depending on the relative strengths and timing of these processes.