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Gas Mass Fractions from XMM-Newton Downloaded from orbit.dtu.dk on: Oct 04, 2021 Gas Mass Fractions from XMM-Newton Ferreira, Desiree Della Monica; Pedersen, Kristian Publication date: 2011 Document Version Publisher's PDF, also known as Version of record Link back to DTU Orbit Citation (APA): Ferreira, D. D. M., & Pedersen, K. (2011). Gas Mass Fractions from XMM-Newton. Niels Bohr Institute. General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. Users may download and print one copy of any publication from the public portal for the purpose of private study or research. You may not further distribute the material or use it for any profit-making activity or commercial gain You may freely distribute the URL identifying the publication in the public portal If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. GAS MASS FRACTIONS FROM XMM-NEWTON DESIREE DELLA MONICA FERREIRA Dissertation Submitted for the Degree PHILOSOPHIÆ DOCTOR Dark Cosmology Centre Niels Bohr Institute Faculty of Science Copenhagen University Submission: December 20th, 2010 Defence: March 4th, 2011 Supervisor: Assoc. Prof. Kristian Pedersen Opponents: Dr. Stefano Ettori Dr. Sabine Schindler CONTENTS Contents i List of Figures v List of Tables vii Acknowledgments ix Abstract xi 1 Introduction 1 1.1 Clusters of Galaxies . 1 1.2 Cluster observations . 2 1.3 Cosmological context . 3 1.4 The gas mass fraction . 6 1.5 This thesis . 7 2 X-ray Observations 9 2.1 Introduction . 9 2.2 X-rays from galaxy clusters . 10 2.3 X-ray Observatories . 12 2.3.1 XMM-Newton vs Chandra . 14 2.4 XMM-Newton . 14 2.4.1 EPIC cameras . 16 2.4.2 EPIC background . 18 2.5 Analysis of XMM-Newton data . 18 2.5.1 SAS . 18 2.5.2 XMM-ESAS . 19 2.5.3 XSPEC . 19 i 3 Sample selection and data processing 21 3.1 The cluster sample . 21 3.2 The standard data processing . 22 3.3 Filtering the data . 25 3.4 MOS images . 25 3.4.1 Examination of CCDs . 26 3.4.2 Point sources . 27 3.4.3 Clean images . 27 3.4.4 The cluster center and number of counts . 29 3.5 MOS Spectra . 30 3.5.1 Particle background spectra . 31 3.5.2 PSF correction . 31 3.6 Final EPIC MOS products . 32 4 The X-ray background 33 4.1 Introduction . 33 4.2 The background components . 33 4.2.1 The quiescent particle background (QPB) . 34 4.2.2 The fluorescent X-ray background . 35 4.2.3 Soft proton background . 35 4.2.4 The cosmic X-ray background (CXB) . 36 4.3 Modeling the Cosmic X-ray Background . 37 4.3.1 The use of RASS spectra . 39 4.3.2 RASS and MOS simultaneous fit . 39 4.4 Results . 40 5 Data Analysis 45 5.1 Introduction . 45 5.2 Spectral Model . 46 5.3 Spectral fitting at R2500 ............................. 47 5.4 Radial analysis - profiles . 49 5.4.1 PSF correction . 51 5.4.2 Deprojected Temperature Profiles . 51 5.4.3 Effect of background model . 52 5.4.4 Metal abundance . 54 5.5 Spatial analysis . 54 5.5.1 The surface brightness profile . 55 5.5.2 Remaining background . 55 5.6 Results . 56 5.7 Discussion . 60 6 Mass Profiles 67 6.1 Introduction . 67 6.2 The total cluster mass . 67 6.2.1 Gas density gradient from the surface brightness profile . 70 6.3 Defining R2500 .................................. 70 6.4 Total cluster mass within R2500 ........................ 71 6.4.1 Assuming an isothermal gas . 72 6.5 The mass profiles . 72 6.6 Modeling the mass profiles . 74 6.6.1 Model mass within R2500 ....................... 75 6.6.2 Concentration parameter . 79 6.7 Gas mass . 79 6.8 The gas mass fraction . 80 6.9 Results and discussion . 80 7 Previous studies 87 7.1 Introduction . 87 7.2 The gas mass fraction sample . 88 7.3 Cosmological constraints . 90 7.4 Previous X-ray studies . 90 7.5 Gravitational lensing . 92 7.6 Discussion . 96 8 Summary and conclusions 97 8.1 Summary of main results . 97 8.2 Future work . 99 Bibliography 101 LIST OF FIGURES 1.1 X-ray and optical images of Abell 963 . 2 1.2 Sunyaev-Zeldovich and gravitational lensing effects . 4 1.3 Cosmological constraints from galaxy clusters . 6 2.1 X-ray spectrum from Abell 963 . 11 2.2 Emission lines in a galaxy cluster . 12 2.3 Diagram of the XMM-Newton orbit . 15 2.4 Diagram of the XMM-Newton spacecraft . 16 2.5 Schematic light path for XMM-Newton telescopes, MOS . 17 2.6 Schematic light path for XMM-Newton telescopes, pn . 17 2.7 Layout of the MOS and pn EPIC cameras . 19 3.1 The cluster sample . 23 3.2 Temporal filtering . 26 3.3 Inspection of CCDs. 27 3.4 Removed point sources, substructure and background. 28 3.5 Concentric annuli in the field of view of Abell 1835. 29 3.6 Annulus surrounding the cluster Abell 963. 30 3.7 The source spectrum of Abell 1413. 31 4.1 Quiescent particle background spectrum and image. 34 4.2 Light curve analysis of ClJ1226.9+3332. 37 4.3 Annulus surrounding Abell 1835 . 39 4.4 The cosmic X-ray background model. 40 4.5 Cosmic X-ray background spectrum. 41 5.1 X-ray spectra of Abell 963. 49 5.2 X-ray spectra of Abell 1413. 50 5.3 Effect of the PSF on the temperature profile of Abell 1835 . 52 5.4 Effect of the X-ray background on the average temperatures. 54 5.5 X-ray surface brightness profiles. 57 v 5.6 Temperature profiles . 61 5.7 Average metal abundances. 63 5.8 Metal abundance profiles. 65 5.9 Gas density profiles. 66 6.1 Gas density profile of the cluster Abell 963 . 69 6.2 Total cluster mass within R2500......................... 73 6.3 Mass profiles. 76 6.4 c2500-M2500 relation. 78 6.5 Best fit parameters of the NFW model. 85 6.6 Gas mass fraction profile of Abell 1835. 86 6.7 Gas mass fraction as a function of redshift . ..
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