ULLYSES T TAURI

T Tauri Stars in Galactic Star-Forming Regions

Note: As of March 2021, updates have been made to the original T Tauri target sample, including removing the TW Hydrae association from the list of star-forming regions to observe. TWA 8A, the only survey target planned for it, fails checks designed to protect COS from M dwarf flares. (The monitoring target TW Hydrae remains in the sample.)

Observations of the ULLYSES low-mass T Tauri star survey sample (listed in the eight tables for different regions) will be obtained with COS/G130M/1291, COS/G160M/1611, STIS/G230L, STIS/G430L, and STIS/G750L. The four stars in the monitoring sample (listed in the final table) will be observed with COS/G160M/1611 and COS/G230L/(2635,2950). The monitoring stars will be observed a total of 24 times each. These observations will be taken in two epochs, separated by several months. There will be four observations per rotation period, and three rotation periods in each epoch. All of the HST data for the low-mass stars will be obtained during HST cycles 28 and 29 (2020-2022). Community groups are planning to obtain the following complementary ground- and/or space-based data: photometry covering the time around the HST observations (for the full sample), spectroscopy from X-ray to mid-IR wavelengths, and spectro-polarimetry (for the four temporally monitored stars).

For each region, the tables give the target name, the stellar position (generally from Gaia DR2 or 2MASS), the adopted spectral type, the stellar mass and accretion rate, and the visual extinction and V magnitude. For the targets to be monitored, the table gives the star name; the position; the stellar mass, radius, accretion rate, and rotational period; and the visual extinction. In each table, three additional columns will be populated (when the information exists), giving the proposal ID, the science configuration (indicating which instruments and channels will be used), and the date of the first observation of that target. Further information about each visit can be found by clicking on the row for the target of interest. An additional table will appear that will contain the visit ID, the scheduling status of that visit, a more detailed science configuration (including grating and central wavelength), and the observation date for each visit.

Chamaeleon I Cloud

Corona Australis Association

ε Chamaeleontis Association

η Chamaeleontis Cluster

Lupus Clouds

Orion OB1 Association

σ Orionis Cluster

Classical T Tauri Star Monitoring Targets