The Vienna Atomic Line Database (VALD) is a collection of atomic line
parameters of astronomical interest and provides tools for selecting
subsets of lines for typical astrophysical applications: line
identification, chemical composition and radial velocity measurements,
model atmosphere calculations etc.
The VALD Electronic Mail Service (VALD-EMS) is the main interface for
accessing VALD by external users. VALD-EMS is aimed to endorse the
following main principles of VALD access.
Mail access lets VALD automatically process requests and queue them for
execution on VALD computers at the most convenient time. It also allows
us to have control over the size of the data traffic and to register
- subsets of spectral line lists are extracted with tools consistent
with the specific astronomical problem. VALD strongly discourages bulk
data transfer for the case of an external access to the data base
and concentrates more on intelligent search and extraction
- VALD provides data sets and extraction tools suitable for several
- VALD is regularly updated with critically evaluated data sets. The
VALD project team experts investigate the statistical properties of
the data, extensively compare the results obtained with different
data sources, and establish the quality rating for each new source.
- VALD computers are not dedicated to the VALD project alone, so the
correct scheduling is important.
Apart from the mail service, this WWW interface has been developed to
facilitate extraction of data from VALD and to contact the VALD staff for