Post on 15-Jan-2016
1 Palermo 20-22nd May
Looking ahead to MOONS
William Tayloron behalf of the MOONS consortium
2 Palermo 20-22nd May
MOONS: Multi Object Optical and Near infra-red Spectrograph
Selected by ESO as third generation instrument for the VLT
Operational by 2019
PI: Michele Cirasuolo
Consortium•UK•France•Italy•Switzerland•Portugal•Chile
Primary science cases:
•Galactic Archeology•Galaxy Evolution
3 Palermo 20-22nd May
Instrument specifics
Parameter Specification
Field of view 25’ diameter (same as FLAMES)
Number of fibres ~1000
Wavelength range 0.8 – 1.8 μm
Throughput > 30%
Fibre diameter 1.05 arcsec
Resolution modes Just “Low” and “High”
Field reconfiguration time < 5 mins
4 Palermo 20-22nd May
MOONS current spectrograph baseline
4
5 Palermo 20-22nd May
Fibre positioners
6 Palermo 20-22nd May
Sky troublesRequire R > 4000 to get continuum between the sky lines
Rodrigues et al., 2012, SPIE
Sky subtraction tests with FLAMES
Proposed A-B-B-A observing strategy
Molecfit – Telluric absorption models
Smette et al., 2014
7 Palermo 20-22nd May
Galactic science case
Coordinators (past and present):Livia Origlia, Carine Babusiaux, Chris Evans, Lex Kaper
Loosely split into:•The bulge •The inner disc•Stellar clusters •Halo of globular clusters•The Magellanic systems•Dwarf galaxies in the local group?•Tidal streams in the MW?•and more…
8 Palermo 20-22nd May
Wavelength selection
IR to give:•penetrating power•for cool stars fewer absorption bands, easier to determine continuum (arguably)•potential to build-on (and learn from) APOGEE survey
Low-res mode:•Calcium Triplet commonly used for metallicity estimates•R>a-few-thousand, RSG abundance determination
High-res mode:•To determine different evolutionary processes need to sample certain species•Include a few DIBs•Windows also chosen to avoid strong telluric absorption
9 Palermo 20-22nd May
Galactic centreH < 15.5 at R~20,000 with a S/N ~ 30 in 1hr
Absorption (Av=0.7mag/kpc; Besancon model)
10 Palermo 20-22nd May
H<15.5 (MOONS R~20,000)
GAIA follow up
MOONS can access all the GAIA targets in the CaT window
11 Palermo 20-22nd May
Data setsGAIA, VISTA, UKIDSS, VPHAS, in the future LSST (?) etc.
From VISTA:
•VISTA Variables in the Vía Láctea (VVV)•VISTA Magellanic Clouds (VMC)
12 Palermo 20-22nd May
ClustersTo observe parameters such as:
•everything discussed in the last 48 hours!
Can do this in both:
•Embedded clusters
•Obscured clusters
Basically: a larger, possibly broader data set
13 Palermo 20-22nd May
VVV ‘new’ clustersBorissova et al., 2011, A&A
Considerations:
•Small spatial scales
•Cluster membership
•Target numbers
•Target density
14 Palermo 20-22nd May
S/LMC…Study kinematics and chemical
abundances of both Clouds to
learn about their interaction and
the impact on their evolution
Low metallicity clusters
…and beyondUse RSG as abundance tracers in nearby
local group galaxies
15 Palermo 20-22nd May
And finally…And finally… possible surveysAnd finally…
Inner Galaxy survey to obtain complete kinematic and chemical screening of the old stellar populations of the inner disc and bulge regions. 1-2 hrs per pointing at R=20,000 in the J- and H-bands (i.e. down to H<15.5 mag) + CaT at R=8,000 for free:
- 50 nights, spectra for ~250,000 stars
Wide-area Gaia survey to follow-up stars observed with Gaia in Thin and Thick disc, tidal streams, the field populations around halo and clusters. 0.5-1hr integration obtain CaT at R=8,000 and simultaneously near-IR low-resolution spectra in J & H-band (i.e. I<21) :
- 50 nights, spectra for ~500,000 stars
Thanks!