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Impact of Feedback on the ISM of Extreme Starburst Galaxies

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Impact of Feedback on the ISM of Extreme Starburst Galaxies Veronica Menacho This thesis presents an analysis of the ionised gas properties and the impact of strong stellar feedback on the interstellar medium of the Impact of feedback on the ISM of starburst galaxy Haro 11. extreme starburst galaxies The case of Haro 11 Veronica Menacho Menacho Impact of feedback on the ISM of extreme starburst galaxies the ISM of extreme starburst on Impact of feedback Veronica Menacho Menacho ISBN 978-91-7911-216-5 Department of Astronomy Doctoral Thesis in Astronomy at Stockholm University, Sweden 2020 Impact of feedback on the ISM of extreme starburst galaxies The case of Haro 11 Veronica Menacho Menacho Academic dissertation for the Degree of Doctor of Philosophy in Astronomy at Stockholm University to be publicly defended on Friday 11 September 2020 at 10.00 in sal FA32, AlbaNova universitetscentrum, Roslagstullsbacken 21. Abstract Blue compact galaxies (BCGs) are compact, metal-poor, starbursting galaxies with characteristics similar to what is expected for the young high-redshifted galaxies. BCGs are among the most active in producing a large number of massive star clusters, each containing thousands of massive stars. During their short life, massive stars are continuously injecting energy, heat and momentum into the ISM via their intense radiation, stellar winds, and later on supernova explosions. These feedback mechanisms impact directly the star's surroundings, but when this feedback originates from a concentration of massive star clusters, it can strongly affect the condition of the gas of the entire galaxy. This thesis presents a detailed analysis of the ionized gas condition and the effect of strong feedback in Haro 11, an extreme starbursting BCG and the closest Lyman continuum (LyC) leaking galaxy. We exploit the spectro-photometric capabilities of the MUSE instrument, by slicing the galaxy spectra in a sequence of maps in velocity bins, in order to obtain a 3D information of the galaxy. Haro 11 has a rich population of massive and predominantly young star clusters, concentrated in three compact knots within its 4 x 4 kpc$^2$ centre. We find that the localised stellar feedback is strongly impacting the global kinematics and the condition of the gas up to further distances in the halo. Many kpc-scale structures such as filaments, shells and bubbles were traced in our data. Moreover, the strong feedback seems to have developed kpc- scale bubbles, outflows and galactic ionized cones with drastic consequences for the likely escape of Ly$\alpha$ and LyC photons, gas and metals out of the galaxy. The extended halo around Haro 11 is governed by photoionization processes and/ or shocks from recurrent supernovae originated in the central starburst region. Due to the galaxy's extreme ISM condition, commonly used emission lines diagnostics produce, in part, large discrepancies in the ionized gas properties. The results presented in this work highlight: a) the strong impact of stellar feedback affecting the ISM at all scales in starburst systems; b) the fact that traditional relations drawn up from averaged measurements of emission lines or from simplified models, fail in probing the condition of the gas in extreme environments. This is an appeal to revisit the standard relations by including more realistic models where several physical processes are simultaneously at work; c) the method applied here can be used to explore in detail the high sensitive, high spatial-resolution data from future facilities such as JWST/ELT. Keywords: Galaxies, stellar feedback, ISM, Integral field spectroscopy. Stockholm 2020 http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-182190 ISBN 978-91-7911-216-5 ISBN 978-91-7911-217-2 Department of Astronomy Stockholm University, 106 91 Stockholm IMPACT OF FEEDBACK ON THE ISM OF EXTREME STARBURST GALAXIES Veronica Menacho Menacho Impact of feedback on the ISM of extreme starburst galaxies The case of Haro 11 Veronica Menacho Menacho ©Veronica Menacho Menacho, Stockholm University 2020 ISBN print 978-91-7911-216-5 ISBN PDF 978-91-7911-217-2 Printed in Sweden by Universitetsservice US-AB, Stockholm 2020 Cover image: 3D view of the ionised gas architecture of Haro 11. It was constructed by slicing up the Halpha spectrum of Haro 11 in bins of 50 km/s in a velocity range - 400 to 350 km/s. 1. Abstract Blue compact galaxies (BCGs) are compact, metal-poor, starbursting galaxies with characteristics similar to what is expected for the young high-redshifted galaxies. BCGs are among the most active in producing a large amount of massive star clusters, each containing thousands of massive stars. During their short life, massive stars are continuously injecting energy, heat and momentum into the ISM via their intense radiation, stellar winds, and later on supernova explosions. These feedback mechanisms impact directly the star’s surround- ings, but when this feedback originates from a concentration of massive star clusters, it can strongly affect the condition of the gas of the entire galaxy. This thesis presents a detailed analysis of the ionised gas condition and the effect of strong feedback in Haro 11, an extreme starbursting BCG and the closest Lyman continuum (LyC) leaking galaxy. We exploit the spectro- photometric capabilities of the MUSE instrument, by slicing the galaxy spectra in a sequence of maps in velocity bins, in order to obtain a 3D information of the galaxy. Haro 11 has a rich population of massive and predominantly young star clusters, concentrated in three compact knots within its 4 x 4 kpc2 centre. We find that the localised stellar feedback is strongly impacting the global kinematics and the condition of the gas up to further distances in the halo. Many kpc-scale structures such as filaments, shells and bubbles were traced in our data. Moreover, the strong feedback seems to have developed kpc-scale bubbles, outflows and galactic ionised cones with drastic consequences for the likely escape of Lyα and LyC photons, gas and metals out of the galaxy. The extended halo around Haro 11 is governed by photoionisation processes and/or shocks from recurrent supernovae originated in the central starburst region. Due to the galaxy’s extreme ISM condition, commonly used emission lines diagnostics produce, in part, large discrepancies in the ionised gas properties. The results presented in this work highlight: a) the strong impact of stellar feedback affecting the ISM at all scales in starburst systems; b) the fact that traditional relations drawn up from averaged measurements of emission lines or from simplified models, fail in probing the condition of the gas in extreme environments. This is an appeal to revisit the standard relations by including more realistic models where several physical processes are simultaneously at work; c) the method applied here can be used to explore in detail the high sensitive, high spatial-resolution data from future facilities such as JWST/ELT. 1 2 CHAPTER 1. ABSTRACT 3 A papa, que construyo mis alas, A mama que me enseno a volar 4 CHAPTER 1. ABSTRACT 2. List of Papers The following papers, referred to in the text by their Roman numerals, are included in this thesis. PAPER I The impact of stellar feedback from velocity-dependent ionized gas maps - a MUSE view of Haro 11 V. Menacho, G. Östlin, A. Bik, L. della Bruna, J. Melinder, A. Adamo, M. Hayes, C. E. Herenz and N. Bergvall, MNRAS, 487, 3183-3198 (2019). DOI:10.1093/mnras/stz1414 PAPER II Ionised gas properties of the extreme starburst galaxy Haro 11. Tem- perature and metal abundance discrepancies V. Menacho, G. Östlin, A. Bik, To be submitted to MNRAS PAPER III Mapping the dominant excitation mechanisms in the extreme star- burst galaxy Haro 11 with MUSE Veronica Menacho, Arjan Bik and Göran Östlin MNRAS, draft version PAPER IV The ionised halo of Haro 11 – a density bounded nebula G. Östlin, V. Menacho, A. Bik, A. Adamo, L. Della Bruna, M. Hayes, J. Melinder and N. Bergvall. To be submitted to MNRAS PAPER V The source of leaking ionising photons from Haro 11 – Clues from HST/COS spectroscopy of knots A, B and C G. Östlin, E. T. Rivera-Thorsen, V. Menacho, M. Hayes, A. Runnholm, S. Oey, M. Mass-Hesse, G. Micheva, A. Adamo, A. Bik, J. Cannon, M. Gronke, D. Kunth, P. Laursen, J. Melinder, M. Messa and L. Smith. To be submitted to ApJ Reprints for papers were made with permission from the publishers. 5 6 CHAPTER 2. LIST OF PAPERS 3. Author’s contribution PAPER I - V I developed a graphical user interface (GUI) in phython which aims to guide a user towards the MUSE data reduction processes. This software has two main functionalities: First, it organises the large amount of raw files and the files generated from the reduction processes and second, it allows for each data reduction step, to configure the parameters/flags and execute the MUSE pipeline. I reduced the MUSE data of Haro 11 (P.I. G. Östlin) following the standard reduction procedures, except for the sky images that was created manually to avoid oversubtraction of the brightest lines in the halo. Papers 1–5 are based on this reduced data cube. PAPER I In this paper I led the entire data analysis and interpretation of the results under guidance of my supervisors. This work is based on spatially and spec- trally resampled emission lines that thereafter were split in 50 kms−1 bins. I developed the software needed to produce the results. I perform all steps to create the final velocity bins maps, except for the stellar absorption correction that was performed by a collaborator. I wrote the entire article and produced almost all figures and all tables. The HST image was provided by a collabora- tor. PAPER II In this paper, I led the entire work under guidance of my supervisors.
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