What is new?

 

Compared with the previous data release, DR9 v2.0, this release introduces the following major updates.

 

1. A new field, "vsini_lasp" has been added to the end of the "LAMOST LRS Stellar Parameter Catalog of A, F, G, and K Stars" catalog. This field provides the projected rotational velocity (vsini) calculated by the LAMOST Stellar Parameter pipeline (LASP), for which detailed explanations are available in the low-resolution data documentation. In this release, vsini values have been provided for 176,114 low-resolution spectra and 412,534 medium-resolution combined spectra. For more details, please refer to the work of Zuo F, et al., 2024^[1].

2. The metallicity parameter "m_h_cnn", derived using a convolutional neural network (CNN) , has been added into the "the LAMOST MRS Parameter Catalog". The corresponding table description of this table has also been updated accordingly.

3. The table description of the "LAMOST LRS Stellar Parameter Catalog for A, F, G, and K-type stars" has been updated. Specifically, it now includes an introduction to the wavelength ranges used for atmospheric parameter measurements of A and F/G/K type stars, respectively. Additionlly, the language expression concerning parameter error estimation has been refined.

4. The spectral templates used for the atmospheric parameter measurement of M type stars in the "LAMOST LRS Catalog of gM, dM, and sdM stars" has been updated, which have been changed from the theoretical template of "BT-Settl CIFIST2011 spectra" to the LAMOST Observed Spectral Library^[2]. Correspondingly, the language in Section 3.4 has also been refined.

 

 

 

 

 

Reference

1. Zuo F., Luo, A.L., Du B., et al. 2024, Projected Rotational Velocities for LAMOST Stars with Effective Temperatures Lower than 9000K, ApJS, 271, 4

2. Bing D.，A-Li,  L., Song, W.  et al.  2024, An Empirical Sample of Spectra of M-type Stars with Homogeneous Atmospheric-Parameter Labels, submitted to ApJS.