The Search for Extremely Low-Metallicity Stars in Dwarf Galaxies Using the NIR Ca II Triplet

Bibcode
2011EAS....48...13S
DOI
10.1051/eas/1148002
Starkenburg, E.; Hill, V.; Tolstoy, E.; González Hernández, J. I.; Irwin, M.; Helmi, A.; Boschman, L.; Francois, P.; Battaglia, G.; Jablonka, P.; Tafelmeyer, M.; Shetrone, M.; Venn, K.; de Boer, T.
Bibliographical reference

EAS Publications Series, Volume 48, 2011, pp.13-18

Advertised on:
7
2011
Number of authors
14
IAC number of authors
0
Citations
1
Refereed citations
1
Description
The NIR Ca II triplet has proven to be an important tool for quantitative spectroscopy. Here we present results of synthetic spectral analysis for the Ca II triplet for low-metallicity red giant stars, combined with observational data. Our results start to deviate strongly from the widely-used and linear empirical calibrations below [Fe/H] = -2. We provide a new calibration for Ca II triplet studies which is valid down until [Fe/H] = -4 and apply this new calibration to current data sets. We suggest that the classical dwarf galaxies are not so devoid of extremely low-metallicity stars as was previously thought and discuss preliminary results and possibilities for follow-up observations of these extremely low-metallicity candidates.
Type
Non-refereed

It may interest you

  • Non-refereed
    Performance of the image persistence model for Euclid infrared detectors
    Large-format infrared detectors are at the heart of major ground and space-based astronomical instruments, and the HgCdTe HxRG is the most widely used. The Near Infrared Spectrometer and Photometer (NISP) of the ESA's Euclid mission launched in July 2023 hosts 16 H2RG detectors in the focal plane. Their performance relies heavily on the effect of
    Kubik, B. et al.

    Advertised on:

    8
    2024
    Bibcode
    2024SPIE13103E..15K
    Citations
    0
  • Non-refereed
    HARMONI at ELT: athermal toroidal mirror mount for HARMONI pre-optics
    HARMONI is the high angular resolution optical and near-IR integral field spectrograph for the Extremely Large telescope (ELT). It covers a large spectral range from 470nm to 2450nm with resolving powers from 3300 to 18000 and spatial sampling from 60mas to 4mas. The Instrument Pre-Optics (IPO), a sub-system under the responsibility of the
    Hernández, Elvio et al.

    Advertised on:

    8
    2024
    Bibcode
    2024SPIE13100E..34H
    Citations
    0
  • Non-refereed
    HARMONI at ELT: project status and instrument overview
    HARMONI is the first light visible and near-IR integral field spectrograph for the ELT. It covers a large spectral range from 450 nm to 2450 nm with resolving powers from 3500 to 18000 and spatial sampling from 60 mas to 4 mas. It can operate in two Adaptive Optics modes - SCAO (including a High Contrast capability) and LTAO - or with NOAO. The
    Thatte, Niranjan A. et al.

    Advertised on:

    7
    2024
    Bibcode
    2024SPIE13096E..14T
    Citations
    0