Skip navigation
Skip navigation
Open Research will be down for maintenance between 8:00am and 8:15am on Monday, 9th December 2019.

Iron and neutron-capture element abundance variations in the globular cluster M2 (NGC 7089)

Yong, David; Roederer, Ian U.; Grundahl, Frank; Da Costa, Gary; Karakas, Amanda; Norris, John; Aoki, Wako; Fishlock, Cherie; Marino, Anna; Milone, Antonino; Shingles, Luke

Description

We present CN and CH indices and Ca II triplet metallicities for 34 giant stars and chemical abundances for 33 elements in 14 giants in the globular cluster M2. Assuming that the programme stars are cluster members, our analysis reveals (i) an extreme variation in CN and CH line strengths, (ii) a metallicity dispersion with a dominant peak at [Fe/H] ≈ -1.7 and smaller peaks at -1.5 and -1.0, (iii) star-to-star abundance variations and correlations for the light elements O, Na, Al and Si and...[Show more]

dc.contributor.authorYong, David
dc.contributor.authorRoederer, Ian U.
dc.contributor.authorGrundahl, Frank
dc.contributor.authorDa Costa, Gary
dc.contributor.authorKarakas, Amanda
dc.contributor.authorNorris, John
dc.contributor.authorAoki, Wako
dc.contributor.authorFishlock, Cherie
dc.contributor.authorMarino, Anna
dc.contributor.authorMilone, Antonino
dc.contributor.authorShingles, Luke
dc.date.accessioned2015-12-13T22:27:12Z
dc.identifier.issn0035-8711
dc.identifier.urihttp://hdl.handle.net/1885/73844
dc.description.abstractWe present CN and CH indices and Ca II triplet metallicities for 34 giant stars and chemical abundances for 33 elements in 14 giants in the globular cluster M2. Assuming that the programme stars are cluster members, our analysis reveals (i) an extreme variation in CN and CH line strengths, (ii) a metallicity dispersion with a dominant peak at [Fe/H] ≈ -1.7 and smaller peaks at -1.5 and -1.0, (iii) star-to-star abundance variations and correlations for the light elements O, Na, Al and Si and (iv) a large (and possibly bimodal) distribution in the abundances of all elements produced mainly via the s-process in Solar system material. Following Roederer, Marino & Sneden, we define two groups of stars, 'r + s' and 'r-only', and subtract the average abundances of the latter from the former group to obtain an 's-process residual'. This s-process residual is remarkably similar to that found in M22 and in M4 despite the range in metallicity covered by these three systems. With recent studies identifying a double subgiant branch in M2 and a dispersion in Sr and Ba abundances, our spectroscopic analysis confirms that this globular cluster has experienced a complex formation history with similarities to M22, NGC 1851 and ω Centauri.
dc.publisherBlackwell Publishing Ltd
dc.rightsAuthor/s retain copyright
dc.sourceMonthly Notices of the Royal Astronomical Society
dc.titleIron and neutron-capture element abundance variations in the globular cluster M2 (NGC 7089)
dc.typeJournal article
local.description.notesImported from ARIES
local.identifier.citationvolume441
dc.date.issued2014
local.identifier.absfor020100 - ASTRONOMICAL AND SPACE SCIENCES
local.identifier.absfor020104 - Galactic Astronomy
local.identifier.absfor020110 - Stellar Astronomy and Planetary Systems
local.identifier.ariespublicationU3488905xPUB3855
local.type.statusPublished Version
local.contributor.affiliationYong, David, College of Physical and Mathematical Sciences, ANU
local.contributor.affiliationRoederer, Ian U., University of Michigan
local.contributor.affiliationGrundahl, Frank, University of Aarhus
local.contributor.affiliationDa Costa, Gary, College of Physical and Mathematical Sciences, ANU
local.contributor.affiliationKarakas, Amanda, College of Physical and Mathematical Sciences, ANU
local.contributor.affiliationNorris, John, College of Physical and Mathematical Sciences, ANU
local.contributor.affiliationAoki, Wako, National Astronomical Observatory of Japan
local.contributor.affiliationFishlock, Cherie, College of Physical and Mathematical Sciences, ANU
local.contributor.affiliationMarino, Anna, College of Physical and Mathematical Sciences, ANU
local.contributor.affiliationMilone, Antonino, College of Physical and Mathematical Sciences, ANU
local.contributor.affiliationShingles, Luke, College of Physical and Mathematical Sciences, ANU
local.bibliographicCitation.issue4
local.bibliographicCitation.startpage3396
local.bibliographicCitation.lastpage3416
local.identifier.doi10.1093/mnras/stu806
dc.date.updated2015-12-11T08:29:25Z
local.identifier.scopusID2-s2.0-84903174662
local.identifier.thomsonID000338764700042
dcterms.accessRightsOpen Access
CollectionsANU Research Publications

Download

File Description SizeFormat Image
01_Yong_Iron_and_neutron-capture_2014.pdf1.49 MBAdobe PDF


Items in Open Research are protected by copyright, with all rights reserved, unless otherwise indicated.

Updated:  22 January 2019/ Responsible Officer:  University Librarian/ Page Contact:  Library Systems & Web Coordinator