In brief
My main research interest is feedback from massive stars, and the key question I am trying to answer is: how exactly do massive stars influence their environment?
We know that massive stars have an enourmous impact on their sourroundings throughout their lifetime via jets/outflows, powerful winds, strong ionising radiation, and ultimately by exploding as supernovae. We can quantify these various feedback mechanisms by simulating one or more at a time, but observationally, the quantification of massive star formation feedback is very challenging.
To observationally quantify feedback from massive stars I use data from so-called integral field spectrographs like MUSE or KMOS on the Very Large Telescope in Chile . With this data, I identify and classify the feedback-driving massive stars while simultaneously linking them to the properties and kinematics of the feedback-driven gas.
I am also a strong advocate for early-career mothers in STEM fields, as well as researchers with unusual paths to astronomy and academia. My wishes for the future: free child care at all major conferences, travel allowances for mothers traveling to conferences with their small (dependant) kids, as well as child care supprt for PhD students and postdocs.
We present optical integral field unit (IFU) observations of the Mystic Mountains, a dust pillar complex in the center of the Carina Nebula that is heavily irradiated by the nearby young massive cluster Trumpler 14. With the continuous spatial and spectral coverage of data from the Multi-Unit Spectroscopic Explorer (MUSE), we measure the physical properties in the ionized gas including the electron density and temperature, excitation, and ionization. MUSE also provides an excellent view of the famous jets HH 901, 902, and 1066, revealing them to be high-density, low-ionization outflows despite the harsh environment. HH 901 shows spatially extended [C I] emission tracing the rapid dissociation of the photoevaporating molecular outflow in this highly irradiated source. We compute the photoevaporation rate of the Mystic Mountains and combine it with recent ALMA observations of the cold molecular gas to estimate the remaining lifetime of the Mystic Mountains and the corresponding shielding time for the embedded protostars. The longest remaining lifetimes are for the smallest structures, suggesting that they have been compressed by ionizing feedback. Our data do not suggest that star formation in the Mystic Mountains has been triggered but it does point to the role that ionization-driven compression may play in enhancing the shielding of embedded stars and disks. Planet formation models suggest that the shielding time is a strong determinant of the mass and orbital architecture of planets, making it important to quantify in high-mass regions like Carina that represent the type of environment where most stars form.
We measure resolved (kiloparsec-scale) outflow properties in a sample of 10 starburst galaxies from the Deep near-UV observations of Entrained gas in Turbulent (DUVET) galaxies sample, using Keck/KCWI observations of H β
and [O III] λ
5007. We measure ∼460
lines of sight that contain outflows, and use these to study scaling relationships of outflow velocity ( vout
), mass-loading factor ( η
; mass outflow rate per star formation rate) and mass flux ( Σ˙out
; mass outflow rate per area) with co-located star formation rate surface density ( ΣSFR
) and stellar mass surface density ( Σ∗
). We find strong, positive correlations of Σ˙out∝Σ1.2SFR
and Σ˙out∝Σ1.5∗
. We also find shallow correlations between vout
and both ΣSFR
and Σ∗
. Our resolved observations do not suggest a threshold in outflows with ΣSFR
, but rather we find that the local specific star formation rate ( ΣSFR/Σ∗
) is a better predictor of where outflows are detected. We find that outflows are very common above ΣSFR/Σ∗≳0.1
Gyr −1
and rare below this value. We argue that our results are consistent with a picture in which outflows are driven by supernovae, and require more significant injected energy in higher mass surface density environments to overcome local gravity. The correlations we present here provide a statistically robust, direct comparison for simulations and higher redshift results from JWST.
We present the first Chandra X-ray observations of H72.97–69.39, a highly embedded, potential superstar cluster in its infancy located in the star-forming complex N79 of the Large Magellanic Cloud. We detect particularly hard, diffuse X-ray emission that is coincident with the young stellar objects identified with JWST, and the hot gas fills cavities in the dense gas mapped by the Atacama Large Millimeter/submillimeter Array. The X-ray spectra are best fit with either a thermal plasma or power-law model, and assuming the former, we show that the X-ray luminosity of L X = (1.0 ± 0.3) × 1034 erg s‑1 is a factor of ∼20 below the expectation for a fully confined wind bubble. Our results suggest that stellar wind feedback produces diffuse hot gas in the earliest stages of massive star cluster formation and that wind energy can be lost quickly via either turbulent mixing followed by radiative cooling or by physical leakage.
