Welcome to VALD3
The Vienna Atomic Line Database (VALD) is a collection of atomic and molecular transition parameters of astronomical interest. VALD offers tools for selecting subsets of lines for typical astrophysical applications: line identification, preparing for spectroscopic observations, chemical composition and radial velocity measurements, model atmosphere calculations etc.
The VALD Electronic Mail Service (VALD-EMS) is the main data transfer protocol for small data sets. For larger data extraction VALD users are advised to use the 'via ftp' option. This web portal is the main user interface to VALD VALD-EMS. It offers full functionality of the extraction tools and flexibility of data access. An alternative user interface and data transfer protocol are offered via the Virtual Atomic and Molecular Data Center (VAMDC). This option allows direct computer access to VALD and many other databases but it lacks some of the functionality that is present in the VALD extraction tools.
Below are the main ideas behind VALD concept that may help you using it in the most efficient way: