November 15, 2022
ULLYSES Data Release 5b (DR5b) consists of high-level science products (HLSPs)
for 17 new ULLYSES low-mass targets. Data releases typically include reprocessed
HLSPs from previous releases, but DR5b is limited to only new products for these
17 T Tauri stars. In addition, a new MAST search form that
provides ULLYSES data, stellar parameters, and observational information is
now available. This
new search form
will be the main platform to query and download ULLYSES data going forward.
DR5b Target Breakdown
The DR5b target sample is limited to the remaining 17 survey T Tauri stars
that were observed too late to be included in DR5 (June 2022). It is
important to be aware of some limitations to the products, listed below:
- DR5b products are limited to HST data only. Corresponding LCOGT
(Las Cumbres Observatory Global Telescope) products will be delivered in
the next release, DR6 (Spring 2023).
- ULLYSES T Tauri stars typically have coverage from the FUV through NIR.
Due to observation failures, however, DR5b targets SZ114 and SZ115 are
limited to FUV data only. There are no plans to repeat observations of these
targets or acquire more data.
ULLYSES Search Form
The ULLYSES team, in partnership with MAST (Mikulski Archive for Space Telescopes),
is proud to announce the release of a new ULLYSES search form. This search form
supports querying targets and datasets based on both observational and
astrophysical parameters, a key functionality given the multi-dimensionality of
the parameter space covered by ULLYSES targets. In addition to specialized
search parameters, the new form also features direct file downloads and customized
API script generation. The search form, which follows the format of the new HST
search form, is fully integrated in MAST to ensure long-term maintainability and legacy.
Some highlights of the new ULLYSES search form are:
- Dedicated search buttons to filter data by most common criteria such as
telescope, instrument, target type, and product type
- Free-form search box to filter data by astrophysical criteria (such as
magnitude, accretion rate, and spectral class), or other observational
criteria (e.g., central wavelength)
- Ability to export results as a CSV, JSON, or VO table
- Astrophysical values obtained from literature are hyperlinked to the
corresponding ADS papers
- Target names are hyperlinked to their Simbad page
- Results table can be sorted by any column(s)
- Ability to download products through user interface or with command-line curl scripts
Products and their contributing data were previously hosted on
the ULLYSES website,
but these have now been removed. To download HLSPs only, the new MAST search
form should be used. To download HLSPs and their contributing data, the MAST
Data Discovery Portal should be used by following
these instructions.
If you have any feedback or questions on using the new ULLYSES search form,
feel free to reach out through the
Archive Help Desk
or send an email to archive@stsci.edu.
DR5b Caveats and Known Issues
Caveats for DR5b data only are listed below. For a complete list of caveats
for all other data, please see the
DR5 notes.
-
The FUV flux in many T Tauri stars can be quite low- in these cases, the
default CalCOS and CalSTIS background subtractions can cause the continuum
flux to dip below zero, particularly longward of 1600Å.
Data Description & Download
A full description of the ULLYSES data products and how they are created can
be found
here.
Data may be downloaded from the
ULLYSES search form
(HLSPs only), the
MAST Data Discovery Portal
(HLSPs and their contributing data), or directly as a High-Level Science Product
collection using the
DOI.
Publications
A description of the ULLYSES observations and data products is given in:
For more information on how to cite ULLYSES data, see
ULLYSES References.
