Cover Page
The handle
http://hdl.handle.net/1887/79821
holds various files of this Leiden University
dissertation.
Author: Zari, E.M.
Surveying young stars with Gaia:
Orion and the Solar neighbourhood
Proefschrift
ter verkrijging van
de graad van Doctor aan de Universiteit Leiden, op gezag van Rector Magnificus prof. mr. C. J. J. M. Stolker,
volgens besluit van het College voor Promoties te verdedigen op dinsdag 22 oktober 2019
klokke 15:00 uur
door
Eleonora Zari
Promotiecommissie
Promotor: Prof. dr. P.T. de Zeeuw
Co-promotor: Dr. A.G.A. Brown
Promotiecommissie: Prof. dr. J. Alves (University of Vienna) Dr. J. de Bruijne (ESA/ESTEC)
Prof. dr. K.H. Kuijken Dr. E. M. Rossi
Prof. dr. H.J.A. Rottgering
ISBN: 978-94-028-1699-0
E quindi uscimmo a riveder le stelle.1
Dante, Inferno, Canto XXXIV
Contents
1 Introduction 1
1.1 Star formation in the Gaia era . . . . 1
1.2 OB associations . . . 2
1.3 The Gould Belt . . . 4
1.4 Orion . . . 5
1.5 OB stars on the run . . . 10
1.6 Gaia . . . 11
1.7 This thesis . . . 12
1.8 Outlook . . . 14
2 Mapping young stellar populations towards Orion withGaia DR1 17 2.1 Introduction . . . 19
2.2 Data . . . 20
2.3 Orion in Gaia DR1 . . . . 21
2.3.1 Distances: the Tycho-Gaia sub-sample . . . . 24
2.3.2 Color magnitude diagrams . . . 27
2.3.3 Source distribution . . . 28
2.3.4 Age estimates . . . 30
2.4 Orion in Pan-STARRS1 . . . 36
2.5 Discussion . . . 38
2.6 Conclusions . . . 42
Appendix 2.A Color Magnitude diagrams . . . 44
Appendix 2.B ADQL queries . . . 47
Appendix 2.C Kernel Density Estimation on the sphere . . . 47
3 Structure, kinematics, and ages of the young stellar populations in the Orion region 51 3.1 Introduction . . . 53
3.2 Data . . . 54
3.2.1 Obtaining a ’clean’ sample . . . 56
3.2.2 Selecting the young stellar population . . . 57
3.3 3D distribution . . . 57 3.4 Kinematics . . . 61 3.4.1 Method . . . 61 3.4.2 Results . . . 63 3.5 Ages . . . 79 3.5.1 Results . . . 81 3.6 Dicussion . . . 82 3.6.1 Kinematics . . . 82 3.6.2 Ages . . . 84
3.6.3 Sequential star formation and triggering in Orion . . . 85
Appendix 3.A Testing the code . . . 87
3.A.1 Simulation set up . . . 87
3.A.2 Simple tests . . . 87
3.A.3 Realistic tests . . . 88
3.A.4 Initial conditions . . . 88
Appendix 3.B Colour magnitude diagrams . . . 93
4 3D mapping of young stars in the solar neighbourhood withGaia DR2 95 4.1 Introduction . . . 97
4.2 Data . . . 98
4.2.1 Extinction correction . . . 98
4.2.2 Upper Main Sequence . . . 99
4.2.3 Pre-Main Sequence . . . 104
4.3 3D maps . . . 109
4.3.1 Method . . . 109
4.3.2 Results . . . 110
4.3.3 Ages of the PMS sample . . . 113
4.3.4 Caveats . . . 113
4.4 Discussion . . . 117
4.5 Conclusion . . . 122
Appendix 4.A ADQL queries . . . 126
Appendix 4.B Source selection . . . 126
Appendix 4.C New cluster . . . 126
Appendix 4.D Age maps . . . 128
Appendix 4.E Density maps corresponding to the top and central panel of Fig. 6 . . . 128
Appendix 4.F UMS and PMS catalogues . . . 128
5 Searching for runaway stars inGaia DR2 131 5.1 Introduction . . . 132
5.2 Data . . . 133
5.3 Method . . . 134
5.3.1 Selection of sources with high tangential velocity . . . 136
5.3.2 Selection of sources with high total velocity . . . 137
5.3.3 3D trace back . . . 137
5.4 Results . . . 141
5.5 Discussion . . . 144
5.5.1 Comparisons with other runaway stars catalogues . . . 144
5.5.2 Comparison with simulations . . . 144
5.5.3 Completeness . . . 145
5.6 Conclusions . . . 145
Appendix 5.A Hoogerwerf . . . 146
Bibliography 150
English Summary 157
Riepilogo 173 List of publications 181
Curriculum Vitae 183
