CaltechAUTHORS
Published June 10, 2019 | Version Published + Accepted Version
Journal Article Open

Star Formation Histories of the LEGUS Spiral Galaxies. I. The Flocculent Spiral NGC 7793

Creators

  • 1. ROR icon Space Telescope Science Institute
  • 2. ROR icon University of Pisa
  • 3. ROR icon INFN Sezione di Pisa
  • 4. ROR icon Stockholm University
  • 5. ROR icon University of Wyoming
  • 6. ROR icon IBM Research - Thomas J. Watson Research Center
  • 7. ROR icon Vassar College
  • 8. ROR icon University of Massachusetts Amherst
  • 9. ROR icon Heidelberg University
  • 10. ROR icon Max Planck Institute for Astronomy
  • 11. ROR icon Australian National University
  • 12. ROR icon National Autonomous University of Mexico
  • 13. ROR icon California Institute of Technology
  • 14. ROR icon Infrared Processing and Analysis Center

Abstract

We present a detailed study of the flocculent spiral galaxy NGC 7793, part of the Sculptor group. By analyzing the resolved stellar populations of the galaxy, located at a distance of ~3.7 Mpc, we infer for the first time its radial star formation history (SFH) from Hubble Space Telescope photometry, thanks to both archival and new data from the Legacy ExtraGalactic UV Survey. We determine an average star formation rate (SFR) for the galaxy portion covered by our F555W and F814W data of 0.23 ± 0.02 M⊙ yr^(−1) over the whole Hubble time, corresponding to a total stellar mass of (3.09 ± 0.33) × 10^9 M⊙, in agreement with previous determinations. Thanks to the new data extending to the F336W band, we are able to analyze the youngest stellar populations with a higher time resolution. Most importantly, we recover the resolved SFH in different radial regions of the galaxy; this shows an indication of a growing trend of the present-to-past SFR ratio, increasing from internal to more external regions, supporting previous findings of the inside-out growth of the galaxy.

Additional Information

© 2019 The American Astronomical Society. Received 2019 February 15; revised 2019 April 17; accepted 2019 April 28; published 2019 June 6. Based on observations obtained with the NASA/ESA Hubble Space Telescope at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy under NASA Contract NAS 5-26555. These data are associated with the HST GO Program 13364 (PI D. Calzetti). Support for this program was provided by NASA through grants from the Space Telescope Science Institute. M.C. and M.T. acknowledge funding from the INAF PRIN-SKA 2017 program 1.05.01.88.04. A.A. acknowledges the support of the Swedish Research Council, Vetenskapsrådet and the Swedish National Space Agency (SNSA).

Attached Files

Published - Sacchi_2019_ApJ_878_1.pdf

Accepted Version - 1905.00020.pdf

Files

1905.00020.pdf

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Additional details

Identifiers

Eprint ID
96763
Resolver ID
CaltechAUTHORS:20190627-081923749

Related works

Describes
https://arxiv.org/abs/1905.00020 (URL)

Funding

NASA
NAS 5-26555
Istituto Nazionale di Astrofisica (INAF)
1.05.01.88.04
Swedish Research Council
Vetenskapsrådet
Swedish National Space Agency (SNSA)

Dates

Created
2019-06-27
Created from EPrint's datestamp field
Updated
2021-11-16
Created from EPrint's last_modified field

Caltech Custom Metadata

Caltech groups
Infrared Processing and Analysis Center (IPAC)