A dwarf disrupting – Andromeda XXVII and the North West Stream. Issue 2 (12th September 2019)
- Record Type:
- Journal Article
- Title:
- A dwarf disrupting – Andromeda XXVII and the North West Stream. Issue 2 (12th September 2019)
- Main Title:
- A dwarf disrupting – Andromeda XXVII and the North West Stream
- Authors:
- Preston, Janet
Collins, Michelle L M
Ibata, Rodrigo A
Tollerud, Erik J
Rich, R Michael
Bonaca, Ana
McConnachie, Alan W
Mackey, Dougal
Lewis, Geraint F
Martin, Nicolas F
Peñarrubia, Jorge
Chapman, Scott C
Delorme, Maxime - Abstract:
- ABSTRACT: We present a kinematic and spectroscopic analysis of 38 red giant branch stars, in seven fields, spanning the dwarf spheroidal galaxy Andromeda XXVII and the upper segment of the North West Stream. Both features are located in the outer halo of the Andromeda galaxy at a projected radius of 50–80 kpc, with the stream extending for ∼3° on the sky. Our data are obtained as part of the PAndAS survey and enables us to confirm that Andromeda XXVII's heliocentric distance is 827 ± 47 kpc and spectroscopic metallicity is $-2.1^{+0.4}_{-0.5}$ . We also re-derive Andromeda XXVII's kinematic properties, measuring a systemic velocity = $-526.1^{+10.0}_{-11.0}$ km s −1 and a velocity dispersion that we find to be non-Gaussian but for which we derive a formal value of 27.0$^{+2.2}_{-3.9}$ km s −1 . In the upper segment of the North West Stream we measure mean values for the metallicity = −1.8 ± 0.4, systemic velocity = −519.4 ± 4.0 km s −1, and velocity dispersion = 10.0 ± 4.0 km s −1 . We also detect a velocity gradient of 1.7 ± 0.3 km s −1 kpc −1 on an infall trajectory towards M31. With a similar gradient, acting in the same direction, in the lower segment we suggest that the North West Stream is not a single structure. As the properties of the upper segment of the North West Stream and Andromeda XXVII are consistent within 90 per cent confidence limits, it is likely that the two are related and plausible that Andromeda XXVII is the progenitor of this stream.
- Is Part Of:
- Monthly notices of the Royal Astronomical Society. Volume 490:Issue 2(2019)
- Journal:
- Monthly notices of the Royal Astronomical Society
- Issue:
- Volume 490:Issue 2(2019)
- Issue Display:
- Volume 490, Issue 2 (2019)
- Year:
- 2019
- Volume:
- 490
- Issue:
- 2
- Issue Sort Value:
- 2019-0490-0002-0000
- Page Start:
- 2905
- Page End:
- 2917
- Publication Date:
- 2019-09-12
- Subjects:
- galaxies: dwarf -- galaxies: fundamental parameters -- galaxies: kinematics and dynamics -- Local Group
Astronomy -- Periodicals
Periodicals
520.5 - Journal URLs:
- http://mnras.oxfordjournals.org/ ↗
http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1365-2966 ↗
http://www.blackwell-synergy.com/issuelist.asp?journal=mnr ↗
http://www.blackwell-synergy.com/loi/mnr ↗
http://ukcatalogue.oup.com/ ↗ - DOI:
- 10.1093/mnras/stz2529 ↗
- Languages:
- English
- ISSNs:
- 0035-8711
- Deposit Type:
- Legaldeposit
- View Content:
- Available online (eLD content is only available in our Reading Rooms) ↗
- Physical Locations:
- British Library DSC - 5943.000000
British Library DSC - BLDSS-3PM
British Library HMNTS - ELD Digital store - Ingest File:
- 12072.xml