JWST's PEARLS: Dust Attenuation and Gravitational Lensing in the Backlit-galaxy System VV 191 Academic Article uri icon

abstract

  • Abstract We derive the spatial and wavelength behavior of dust attenuation in the multiple-armed spiral galaxy VV 191b using backlighting by the superimposed elliptical system VV 191a in a pair with an exceptionally favorable geometry for this measurement. Imaging using the James Webb Space Telescope and Hubble Space Telescope spans the wavelength range 0.34.5 m with high angular resolution, tracing the dust in detail from 0.61.5 m. Distinct dust lanes continue well beyond the bright spiral arms, and trace a complex web, with a very sharp radial cutoff near 1.7 Petrosian radii. We present attenuation profiles and coverage statistics in each band at radii 1421 kpc. We derive the attenuation law with wavelength; the data both within and between the dust lanes clearly favor a stronger reddening behavior (R = A V /E BV 2.0 between 0.6 and 0.9 m, approaching unity by 1.5 m) than found for starbursts and star-forming regions of galaxies. Power-law extinction behavior gives = 2.1 from 0.60.9 m. R decreases at increasing wavelengths (R 1.1 between 0.9 and 1.5 m), while steepens to 2.5. Mixing regions of different column density flattens the wavelength behavior, so these results suggest a different grain population than in our vicinity. The NIRCam images reveal a lens arc and counterimage from a background galaxy at z 1, spanning 90 azimuthally at 2.8 from the foreground elliptical-galaxy nucleus, and an additional weakly lensed galaxy. The lens model and imaging data give a mass/light ratio M/L B = 7.6 in solar units within the Einstein radius 2.0 kpc.

published proceedings

  • ASTRONOMICAL JOURNAL

altmetric score

  • 212.352

author list (cited authors)

  • Keel, W., Windhorst, R., Jansen, R., Cohen, S., Summers, J., Holwerda, B., ... Zitrin, A.

citation count

  • 0

complete list of authors

  • Keel, William CC||Windhorst, Rogier AA||Jansen, Rolf AA||Cohen, Seth HH||Summers, Jake||Holwerda, Benne||Bradford, Sarah TT||Robertson, Clayton DD||Ferrami, Giovanni||Wyithe, Stuart||Yan, Haojing||Conselice, Christopher JJ||Driver, Simon PP||Robotham, Aaron||Grogin, Norman AA||Willmer, Christopher NA||Koekemoer, Anton MM||Frye, Brenda LL||Hathi, Nimish PP||Ryan Jr, Russell EE||Pirzkal, Nor||Marshall, Madeline AA||Coe, Dan||Diego, Jose MM||Broadhurst, Thomas JJ||Rutkowski, Michael JJ||Wang, Lifan||Willner, SP||Petric, Andreea||Cheng, Cheng||Zitrin, Adi

publication date

  • April 2023