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Information × Registration Number 0217U004834, 0115U003737 , R & D reports Title Study of main physical properties of galaxy clusters at big redshifts (z>1) popup.stage_title Head Babyk Yurii Viktorovych, Registration Date 07-03-2017 Organization Main Astronomical Observatory popup.description2 1. Within reporting period, it was selected 30 galaxy clusters with redshift higher 1. The value of redshift as well as presence or not the merging and summetry of cluster were main selecting criteria that is needed to use hydrostatic equilibrium and spherical summetry. The signal-to-noise ratio is significant to obtain confident values of physical characteristics of galaxy clusters. XMM-Newton and Chandra observatories provide the best values of signal-to-noise ratio at 0.5-10.0 keV, as a result, an analysis of images and spectra of selected clusters were performed within quoted energy band. 2. To improve our measurements, the images of clusters have been splitted on concentric annuli with the same value of X-ray photons inside, as a result, we got smaller value of uncertainties. As it was mentioned above, the data reduction of XMM-Newton and Chandra observations require specific steps of analysis. First of all, we need to get deprojected values of physical parameters, so we took deprojection into account to build realistic profiles within radius of cluster. The redshift range has been chosen within 1.0 < z < 1.8. The maximum value of redshift is quoted for JKCS041, that is the most distant cluster to date. For all objects of our sample, the data reduction were performed and the main physical parameters as temperature, metalicity and luminosity were obtained. The brightness, density and mass profiles were built using dark matter density profile Navarro-Frank-White. 3. During our work, the main forces were stopped on JKCS041 cluster, that is the most distant cluster at moment of writing this report that was observed by Chandra. For this cluster, we found the main physical characteristics and performed the comparison of these parameters with previous our results for distant clusters and for nearby as well. 4. All other clusters of our sample were analyzed in the same manner as for JKCS041. The results of this work was written in an article and submitted to MNRAS journal. Moreover, we also performed the same analysis for nearby clusters observed by Suzaku X-ray Observatory. Product Description popup.authors Бабик Ю.В., popup.nrat_date 2020-04-02 Close