Testing different methods for atmospheric parameters determination. The case study of the Am star HD\,71297

TL;DR

This study compares classical spectral synthesis and VWA methods for determining atmospheric parameters of the Am star HD 71297, finding both methods yield consistent and accurate results comparable to direct measurements.

Contribution

It provides a detailed comparison of two spectroscopic approaches for atmospheric parameter determination on a bright Am star, validating their accuracy against direct measurements.

Findings

Spectroscopic methods produce results consistent with direct measurements.

HD 71297 shows moderate underabundances of certain elements.

Both methods confirm the star's chemical pattern.

Abstract

In this paper we present a detailed spectroscopic analysis of the suspected marginal Am star HD\,71297. Our goal is to test the accuracy of two different approaches to determine the atmospheric parameters effective temperature, gravity, projected rotational velocity, and chemical abundances. The methods used in this paper are: classical spectral synthesis and the {\it Versatile Wavelength Analysis} ({\sl VWA}) software. Since our star is bright and very close to the Sun, we were able to determine its effective temperature and gravity directly through photometric, interferometric, and parallax measurements. The values found were taken as reference to which we compare the values derived by spectroscopic methods. Our analysis leads us to conclude that the spectroscopic methods considered in this study to derive fundamental parameters give consistent results, if we consider all the sources of experimental errors, that have been discussed in the text. In addition, our study shows that the spectroscopic results are quite as accurate as those derived from direct measurements. As for the specific object analyzed here, according to our analysis, HD\,71297 has chemical abundances not compatible with the previous spectral classification. We found moderate underabundances of carbon, sodium, magnesium, and iron-peak elements, while oxygen, aluminum, silicon, sulfur, and heavy elements (Z $\geq$ 39) are solar in content. This chemical pattern has been confirmed by the calculations performed with both methods.