Free Access
Volume 527, March 2011
Article Number A24
Number of page(s) 19
Section Galactic structure, stellar clusters and populations
Published online 20 January 2011

Online material

Appendix A: Table new members

Table A.1

Confirmed spectroscopic members of the USco association AAOmega (first part) and GNIRS (second part).

Appendix B: Classification of stars in the AAOmega field

The full sample of over 600 stars in the AAOmega field assigned to a fibre in addition to the USco member candidates is available electronically (Table B.1). An example of the table is provided below for guidance only. Columns 1 and 2 give the coordinates (J2000); Cols. 3–7 the ZYJHK photometry, Cols. 8–9 the proper motions (in mas/yr) in right ascension and declination, respectively; Col. 10 the spectral types based on the visual comparison with the templates listed below; and Col. 11 the name give prior to the fibre assignment.

This sample can be divided into several groups, each of them characterised by one template with a good quality spectrum (see Fig. B.2). Spectral types of M dwarfs should be accurate to half a subclass whereas others are tentative spectral types. The templates are:

  • UGCS J160709.43−234031.8 or field6062 classified as M1.5;

  • UGCS J160709.43−234031.8 or field3147 classified as M2;

  • UGCS J160709.43−234031.8 or field4452 classified as M2.5;

  • UGCS J160709.43−234031.8 or field2656 classified as M3–M3.5;

  • UGCS J160709.43−234031.8 or field1771 classified as M4;

  • UGCS J160709.43−234031.8 or field6901 classified as M4.5;

  • UGCS J160709.43−234031.8 or field1296 classified as M5.25–5.5;

  • UGCS J160709.43−234031.8 or field633 classified as M5.75–M6;

  • Four objects classified as dM6 +  i.e. later than M6;

  • UGCS J160634.44−231517.7 or field3830 is classified as a late-K/early-M;

  • UGCS J160709.43−234031.8 or field2636 is classified as a late-K/early-M;

  • UGCS J160733.42−224609.4 or field477 is classified as late-K/early-M and show a different level of reddening than field3830. The position of these objects in the (HK, JH) colour-colour diagram (Fig. B.1) corroborate the classification as dwarfs rather than giants (e.g. Fig. 5 in Dobbie et al. 2002a). However, we can not rule our that some giants are included in this sample;

  • UGCS J160544.57−231310.6 or field522 is classified as a late-K dwarf or giant;

  • UGCS J160632.31−224817.2 or field1530 is classified as a late-G giant. Sources in this group show similar features but may have different levels of reddening;

  • Two white dwarfs: UGCS J160757.34−231248.5 (field4930) and UGCS J160917.16−231020.1 (field1861);

  • Three young active flare M dwarfs, see Sect. 5.4;

  • 18 objects unclassified;

  • 11 objects with no signal.

thumbnail Fig. B.1

(HK, JH) two-colour diagram for stars in the AAOmega field.

Open with DEXTER

thumbnail Fig. B.2

Example of optical spectra obtained with AAT/AAOmega for for stars in the AAOmega field not selected as photometric candidates. Spectra are normalised at 7500 Å and offset for clarity. Left: a sample of field M dwarfs with spectral types ranging from M1 to M6. Right: a sample of late-K/early-M dwarfs, giants, white dwarfs, and young active M dwarfs.

Open with DEXTER

Table B.1

Coordinates (J2000), ZYJHK photometry, and proper motions (in arcsec/yr) of stars in the AAOmega field ordered by increasing Z magnitude.

Appendix C: Proper-motion non-members

Table C.1

Proper motion non members from Lodieu et al. (2007b) observed during our AAOmega spectroscopic follow-up.

Appendix D: Candidates with proper motion and equivalent widths satisfying membership

Table D.1

List of 50 candidates with proper motion within 3σ from the cluster mean motion and with equivalent widths measurements of Hα and the Na I doublet consistent with membership.

© ESO, 2011

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