"Angular Size-Redshift" Relation and Its Constraining on Cosmological Parameter

• Main Authors: Rong-Ying Ronin Wu, 吳容瑩
• Other Authors: Tzihong Ｃhiueh
• Format: Others
• Language: en_US
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/85673119898235296595

碩士 === 國立臺灣大學 === 物理學研究所 === 91 === In this thesis, we analyze data released by VLBI observations on 330 compact radio sources. These sources are locating in the range of $0.011\leqslant z \leqslant4.715$, while under luminosity selection criterion, $Lh^{2}\geqslant10^{26}W/Hz$, we are left with 281 data points which are taken as the sources for our study on ''angular size-redshift'' relation. We adapt here a quintessence-cold dark matter (QCDM) model to pin down the energy density parameter for matter ($\Omega_{m}$) as well as the equation of state to quintessence and, instead of taking these sources as ''standard rods'', we further study the evolution of their linear sizes. In our analysis we introduce a dependence of linear sizes on the spectral index as $l\varpropto$$e^{k\alpha}$ and while k is set to be around -1.5 the deviation among the data points is reduced to its minimum.