Resolved Metallicity and Age Gradients in the Lensed Quiescent Galaxy AGEL0014 at z ≈ 1.4

Ahmad Al-Imtiaz

Graduate Research Assistant, CASSA, IUB, Bangladesh

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Nicha Leethochawalit

Researcher, NARIT, Thailand

Objective

• The Gap: Resolved chemical data for quenching galaxies at 1 < z < 2 is critically scarce. [1]
• Cosmic Clocks: Decouple Iron (slow SNe) from Magnesium (fast SNe) to time the final starburst.
• Quenching Pathway: Map age and metallicity gradients to determine if the galaxy died "inside-out" or "outside-in."

Photometric Data

• Why do we need this data: AO and High resolution

J (31) (1100nm to 1400nm)

Photometric Data

Kshort (6) (2000nm to 2400nm)

H (17) (1500nm to 1800nm)

Ingredients for the lens modeling

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Steps:

• Cutout: data and error map
• Star cutout for psf estimation
• Point spread function estimation using psfr by Simon Birrer (Stony Brook Uni.)

https://github.com/sibirrer/psfr

Lens Modeling with Lenstronomy

• Mass profile of the lens galaxy: Elliptical Power Law [2]
• Light profile of the lens and source galaxies: SERSIC ELLIPSE [3]
• Multi-band solution: one joint solution across the bands
• Joint solution of mass and light: center_x, center_y, e1, e2

Assumptions

Lens Modeling Outputs

Lens Modeling Outputs

Keck/MOSFIRE Observation

Absorption Line Fitting

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with alf (Conroy et al. 2012 & 2018)

Forward Modeling of log(Age)

Forward Modeling of Total Metallicity

Forward Modeling of [Fe/H]

Forward Modeling of [Mg/Fe]

Evolution History

Outside-In Quenching: The outer disk died first (~3.06 Gyr); the dense core survived longer (~2.36 Gyr).

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The Slow Clock (Halo): Steady outer star formation allowed slow Type Ia SNe to forge an Iron-rich halo.

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The Fast Clock (Core): Fast Type II SNe flooded the core with Magnesium, then abruptly blew away the gas before Iron could form.

References

1. Jafariyazani et al. 2020, ApJL, Volume 897, Number 2
2. Tessore, N., & Metcalf, R. B. 2015, A&A, 580, A79
3. Sérsic, J. L. 1968, Atlas de Galaxias Australes (Cordoba, Argentina: Observatorio Astronomico)
4. Conroy, C., & van Dokkum, P. 2012, ApJ, 747, 69
5. Conroy, C., Villaume, A., van Dokkum, P. G., & Lind, K. 2018, ApJ, 854, 139

Thank You