Extended star clusters in NGC 1023 from HST/ACS mosaic imaging

Duncan A. Forbes*, Andres Almeida, Lee R. Spitler, Vincenzo Pota

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

10 Citations (Scopus)
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Faint fuzzies (FFs) are a relatively new class of star cluster, first found in the nearby S0 galaxy NGC 1023 by Larsen & Brodie using Wide Field Planetary Camera 2 (WFPC2) images from the Hubble Space Telescope (HST). Here, we investigate the star cluster system of NGC 1023 using an eight pointing mosaic of Advanced Camera for Surveys (ACS) images from HST. We identify blue and red normal globular clusters (two of which are particularly luminous and dense) and two ultracompact dwarf objects (with effective radius ∼ 10 pc).With our more complete spatial coverage, we also find 81 red and 27 blue FFs. We confirm the association of the red FFs with the disc of NGC 1023, consistent with them being long-lived open clusters. Half of the blue FFs appear to be associated with the dwarf satellite galaxy NGC 1023A (which was largely absent from the original HST/WFPC2 coverage), while the remainder are spatially coincident with the densest H I gas that surrounds NGC 1023. The blue FFs have colours that are consistent with young (few 100 Myr old) star clusters that formed during the most recent interaction between NGC 1023 and its satellite NGC 1023A.

Original languageEnglish
Pages (from-to)1049-1053
Number of pages5
JournalMonthly Notices of the Royal Astronomical Society
Issue number2
Publication statusPublished - 1 Aug 2014

Bibliographical note

Copyright 2014 The Authors. First published in Monthly Notices of the Royal Astronomical Society, 442(2), 1049-1053. The original publication is available at http://doi.org/10.1093/mnras/stu940, published by Oxford University Press on behalf of the Royal Astronomical Society. Version archived for private and non-commercial use with the permission of the author/s and according to publisher conditions. For further rights please contact the publisher.


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