Names of science files must follow the naming scheme described here. This
convention permits easy integration with MAST in a way that allows for
automated searches. Elements of file names in black bold text, including
underscores and periods, are literal text; items in
blue italic text are
symbolic, and are explained below. Some examples of valid filenames are given
a literal string that identifies the file as a
community-contributed data product.
An agreed upon identifier for the HLSP collection (e.g. a
project acronym). This name is also used as directory name and as a database
Primary observatory used to acquire the data. If multiple
observatories were used, select one to be the primary in this context.
Instrument (and if applicable, channel) used to obtain the data (e.g.
acs-wfc). When not applicable (e.g. for
GALEX data), a descriptive tag like imaging or
spectra will suffice.
Field name or target as designated by the team. Parts, counter numbers, and
epochs are allowed in this field and should be separated by hyphens. Counters
can be used when the same field is observed multiple times with same observing
If multiple observing epochs apply, please use the literal suffix
ep followed by a number (e.g.
For parts and counters, leading zeros are required if more than one
digit is needed (e.g. for 17 exposures of m101,
each file has field-name as follows:
m101-01, m101-02 ... m101-17;
similarly, for more than 9 epochs:
m101-ep01 ... m101-ep19).
Please describe your usage of field-name parts and counters within the
collection README file.
Names of optical element(s), i.e., filter or dispersing element, used to
obtain the data.
For HST data this element should be the full filter or grating name
(e.g. f606w or g230m).
If more than one optical element is used, separate them by hyphens
Version designation used by the team for the HLSP delivery,
such as v#.#. e.g. v2.4
Type of data as designated by the team (models/simulations
can be indicated here). Please use a widely recognized type when possible;
img, drz, sci, weight, wht, cat, theory, sim, model, map,
Standard file format extension, e.g.
.fits, .txt, or .jpg
Appending an extension beyond the standard one, indicating the output
of a common compression algorithm, is acceptable: e.g.,
.gz or .bz2
Use lower-case characters only.
Only use underscores to delineate major fields (e.g.
Within fields, dashes can be used as separators (e.g.
Version numbers can be specific to the project. We recommend that teams
use increasing version numbers to make it easy to tell which data are
superseded; MAST will NOT keep older versions of datasets unless the team
explicitly requests this. Note that sometimes version numbers may denote
single-EPOCH (data as in the
GOODS collection); this
sort of information must be documented well with deliveries.
We recommend that re-delivered data be given with higher version numbers
(to indicate better products); we recommend that the newest deliveries
contain both the re-processed data along with the single-epoch data
associated with these products, if applicable.
All images identified using the same field-name should cover
approximately the same area of the sky. If there are multiple images
covering different parts of a field or source, they should have different
Example File Names
A drizzle-combined image of the GOODS field, obtained with the HST/ACS camera
WFC channel using the F435W filter: