Description
Time-resolved data is a powerful tool to investigate spatial scales well beyond the range of direct imaging and ‘using time to map space’ is the only feasible method to study small-scale processes and structures, for a statistically significant numbers of sources. I will present my study of time variability, in the spectroscopy and photometry, of young intermediate-mass stars comprising of HAeBe and massive T Tauri stars. I will also
highlight our analysis from the North-PHASE legacy survey on the young stellar cluster, NGC 2264.
We studied the variability of 26 well-known young objects, with analysis data received by CARMENES and supplemented by archive data. We found that variability must be determined, as stellar properties change significantly depending on how they have been measured in the photometry. The time-resolved spectra assisted in distinguishing rotational modulation from accretion variations, as we measured the variability in velocity and relative intensity for different lines (including metallic ones). This work also unveils the structures and processes in these objects at the relevant scales for inner planet formation.
North-PHASE investigates stellar variability on timescales from days to years for thousands of young stars. With Gaia, we studied the star formation history of NGC 2264 and explored its subcluster structure. We used variability indices to detect different types of variable stars in NGC 2264, which unveiled members that are YSO proper motion outliers. Thus, we can complete the results of Gaia, exposing a diverse variable star population and revealing the true kinematics of the entire cluster.
