Annual report for the second year of post-graduate course.

During last year I have carried out three tasks.
Firstly, it was a spectroscopic analysis of the molecular hydrogen absorption system at z=2.811 in Q0528-250 quasar spectrum. We have shown, that taking into account the partial coverage of quasar emission regions by an compact intervening H2 cloud can significantly change the value of column density (up to two order of magnitude) and therefore change the physical parameters related with it. Physical parameters of H2 absorption system were estimated by Markov Chain Monte Carlo Method (MCMC) method.
Secondly, it was the systematic search of molecular hydrogen absorption systems in Sloan Digital Sky Survey (SDSS) Data realizes 9 (DR9). For this problem I have made automatic procedure of quasar continuum construction. This procedure based on two methods: the Principal Component Analysis and the Statistical approaches method. Also I have performed modeling of SDSS-like quasar spectrum catalog to validate our searching criteria. This catalog repeats the main features of the catalog SDSS. An important feature of the study is that simulated spectra are produced with the same noise and flux distributions as in the actual SDSS data. Modeling also allowed us to estimate the minimal S/N ratio, redshift and H2 column density at which the detection of H2 systems is possible.
Thirdly, I have applied Markov MCMC method to QSO spectrum processing. Unlike previous simply optimization algorithms (such as a Newton method), this method does not requires special knowledge of covariance matrix accuracy values of which are limited by the accuracy of calculations. I have wrote new parallel program of QSO spectrum processing with using MCMC algorithm and performed calculation of physical parameters of H2 absorption system in Q0528-250 quasar spectrum.

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