The Las Campanas Stellar Library: An Essential Tool to Interpret NIR Spectra of Galaxies

Thursday, 01 June 2017 9 a.m. — 10 a.m. MST

AURA Lecture Hall

NOIRLab South Colloquia
IGOR CHILINGARIAN (CfA / Moscow State University and NOAO South Visiting Astronomer)

We present the most comprehensive up-to-date intermediate resolution (R=6500) stellar library, which covers the entire near-infrared wavelength range (0.83 to 2.5um). It contains spectra of 1000+ stars across the HR diagram collected with the FIRE spectrograph at the 6.5m Magellan Baade telescope processed with a dedicated bright source data reduction pipeline. Among others, our library includes about 250 AGB stars, 50 LMC/SMC stars, and also a sample of chemically peculiar stars. We have about 150 stars in common with the X-Shooter Spectral Library project which will allow us to perform cross-checks, assess the data quality and pin down potential systematic problems. By the start of the JWST mission we plan to produce a new generation of stellar population models which will enable the extragalactic community to interpret nearby galaxy spectra in the NIR and analyze unresolved stellar populations in a manner similar to the one used in the optical domain. The spectral resolution will be sufficient to study internal kinematics and stellar content of dwarf galaxies and nuclear star clusters in nearby galaxies. For about 650 stars, we built complete optical-to-NIR spectra at R=6500 using re-calibrated optical spectra from INDO-US and UVES-POP stellar libraries.

If I have time, apart from the stellar library, I will also talk about some aspects of the ground-based NIR spectroscopy in general, which are very important for the data analysis and interpretation but are usually known only to people working very closely to instruments/telescope operations.