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arXiv · 2503.16729

NEIDSpecMatch: stellar parameter estimation with NEID spectra using an empirical library

Te Han·Paul Robertson·Caleb I. Cañas·Gudmundur Stefansson·Shubham Kanodia·Joe P. Ninan·Jaime A. Alvarado-Montes·Chad F. Bender·Jiayin Dong·Rachel Fernandes·Arvind F. Gupta·Samuel Halverson·Daniel M. Krolikowski·Andrea S. J. Lin·Suvrath Mahadevan·Leonardo A. Paredes·Arpita Roy·Christian Schwab·Ryan C. Terrien
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Abstract

We introduce NEIDSpecMatch, a tool developed to extract stellar parameters from spectra obtained with the NEID spectrograph. NEIDSpecMatch is based on SpecMatch-Emp and HPFSpecMatch, which estimate stellar parameters by comparing the observed spectrum to well-characterized library spectra. This approach has proven effective for M dwarfs. Utilizing a library of 78 stellar spectra covering effective temperatures from $3000-6000$ K, NEIDSpecMatch derives key parameters, including effective temperature, metallicity, surface gravity, and projected rotational velocity. Cross-validation shows median uncertainties of $\sigma_{T_{\mathrm{eff}}} = 115\,\mathrm{K}$, $\sigma_{[\mathrm{Fe/H}]} = 0.143$, and $\sigma_{\log g} = 0.073$ across 49 orders. We showcase its application by fitting the spectrum of an M-dwarf and discuss its utility across a wide range of spectra observed with NEID. NEIDSpecMatch is pip-installable.

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Te Han, Paul Robertson, Caleb I. Cañas, Gudmundur Stefansson, Shubham Kanodia, Joe P. Ninan, Jaime A. Alvarado-Montes, Chad F. Bender, Jiayin Dong, Rachel Fernandes, Arvind F. Gupta, Samuel Halverson, Daniel M. Krolikowski, Andrea S. J. Lin, Suvrath Mahadevan, Leonardo A. Paredes, Arpita Roy, Christian Schwab, Ryan C. Terrien. 2025-03-20. NEIDSpecMatch: stellar parameter estimation with NEID spectra using an empirical library. https://arxiv.org/abs/2503.16729

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