Leicester Database and Archive Service Overview
LEDAS provides an on-line
astronomical database and archive access service biased towards data from high
energy astrophysics missions. Our three main datasets are as follows:
addition to these, LEDAS also provides access to hundreds of other astronomical
catalogues from ground-based observations and other space missions.
UK ASCA Public Data Archive was released in November
1998. It provides access to ASCA images and data files and is a mirror
of the ASCA archive held by HEASARC at GSFC, in the USA. Data from this
on-going mission is ingested into the database as soon as it is received from
was the most successful X-ray astronomy mission to date, completing nearly a decade
of successful in-orbit operations. The UK
ROSAT Public Data Archive contains all public data from the X-ray telescope
obtained during the pointed observation phase of the mission. LEDAS also archives
and provides access to Wide Field Camera data from the All-sky Survey and pointed
phases of the mission.
Ginga Data Products Archive was conceived and created
by the Ginga support staff at Leicester. Users of the Ginga archive
can obtain reduced, quality controlled data products (data cubes, light curves
and spectra), thereby making Ginga data more accessible to the typical
astronomer. The archive was completed and released in January 1998.
Accessing the archives:
collection can be accessed via the Web using the ARchive Network InterfacE (ARNIE).
The Digitized Sky Survey:Since
1998 LEDAS has offered an optical sky image creation service, the Digitized
Sky Survey (DSS) Image Browser. The DSS browser is an online digitised version
of Schmidt survey plates covering the entire sky at 1.7" resolution. The LEDAS
DSS service offers access to the full sky, and users are able to request images
up to 1.8 degrees square in FITS, HDS and GIF formats. Thre is also a batch request
service available which allows up to 15 images to be requested at once.
To help UK astronomers avoid the potentially awkward and time-consuming process
of downloading X-ray data analysis software packages from the USA, LEDAS maintains
a web mirror of several commonly used software packages.
data analysis software
data analysis software
is a comprehensive suite of programs covering many aspects of X-ray data analysis,
including imaging, spectral modelling and timing analysis.
is a collection of utility programs used extensively in X-ray astronomy to create,
examine, or modify the contents of FITS data files.
is a popular tool for simulating count rates from most X-ray missions, based on
count rates and assumed spectra from other missions.