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Research output: Contribution to Journal/Magazine › Journal article
Research output: Contribution to Journal/Magazine › Journal article
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TY - JOUR
T1 - LAMPSS: Discovery of Metal-Poor Stars in the Galactic Halo with the CaHK filter on CFHT MegaCam
AU - Worrell, Eleanor
AU - Patel, Niam
AU - Wresilo, Karolina
AU - Dicker, Sam
AU - Bray, Olivia
AU - Bagness, Jack
AU - Sobral, David
N1 - Worrell et al. (2019), NLUAstro, 1, 75
PY - 2019/6/7
Y1 - 2019/6/7
N2 - We present the Lancaster Astrophysics Metal Poor Star Search (LAMPSS) in the Milky Way halo, conducted using the metallicity-sensitive Ca H & K lines. We use the CaHK filter of the MegaPrime/MegaCam on the Canada-France-Hawaii Telescope (CFHT) to survey an area of 1.010deg2 over the COSMOS field. We combine our new CaHK data with broadband optical and near-infrared photometry of COSMOS to recover stars down to mHK ∼ 26. After removing galaxies, we find 70% completion and 30% contamination for our remaining 1772 stars. By exploring a range of spectral types and metallicities, we derive metallicity-sensitive colour-colour diagrams which we use to isolate different spectral types and metallicities (−5 ≤ [Fe/H ≤ 0). From these, we identify 16 potentially extremely metal-poor stars. One of which, LAMPS 1229, we predict to have [Fe/H] ∼ −5.0 at a distance of (78.21 ± 9.37) kpc. We construct a Metallicity Distribution Function for our sample of metal-poor stars, finding an expected sharp decrease in count as [Fe/H] decreases.
AB - We present the Lancaster Astrophysics Metal Poor Star Search (LAMPSS) in the Milky Way halo, conducted using the metallicity-sensitive Ca H & K lines. We use the CaHK filter of the MegaPrime/MegaCam on the Canada-France-Hawaii Telescope (CFHT) to survey an area of 1.010deg2 over the COSMOS field. We combine our new CaHK data with broadband optical and near-infrared photometry of COSMOS to recover stars down to mHK ∼ 26. After removing galaxies, we find 70% completion and 30% contamination for our remaining 1772 stars. By exploring a range of spectral types and metallicities, we derive metallicity-sensitive colour-colour diagrams which we use to isolate different spectral types and metallicities (−5 ≤ [Fe/H ≤ 0). From these, we identify 16 potentially extremely metal-poor stars. One of which, LAMPS 1229, we predict to have [Fe/H] ∼ −5.0 at a distance of (78.21 ± 9.37) kpc. We construct a Metallicity Distribution Function for our sample of metal-poor stars, finding an expected sharp decrease in count as [Fe/H] decreases.
M3 - Journal article
VL - 1
SP - 75
EP - 90
JO - Notices of Lancaster Astrophysics (NLUAstro)
JF - Notices of Lancaster Astrophysics (NLUAstro)
ER -