我參與的研究利用對撞機搜尋衰變自希格斯玻色子並伴隨產生兩個底夸克的暗物質。我在這個研究組中負責的工作是關於與可變半徑噴注的引入。可變半徑噴注的特色是其半徑參數與噴注本身的橫向動量成反比。我們採用頂夸克對事件樣本，應用最大似然估計，對數據模擬中的底夸克的辨識效率進行校準，我們採用的辨識演算法為MV2c10，數據則是由超環面儀器在2015年和2016年以13TeV的能量收集。可變半徑噴注有助於改進底夸克的辨識率，而我的工作則幫助研究組能實際應用可變半徑噴注於分析當中，提高增強希格斯識別的性能，從而提供更好的研究表現。

I involve in a collider search for dark matter produced in association with a Higgs boson decaying to two bottom quarks, which is simply called ``Mono-H(bb)" search. My work among this search is related to the application of variable radius (VR) jets.

VR jets are jets constructed with variable radius jet algorithm whose radius parameters are inversely proportional to the transverse momentum of the jets. We apply likelihood based calibration on the VR jets to measure the $b$-jet efficiency of the MV2c10 $b$-tagging algorithm in samples of top quark pair events where both W bosons from top quarks decay leptonically. Correction factors from the difference between data and Monte Carlo simulation for the $b$-jet efficiency are computed in bins of the transverse momentum ($p_T$) of the jet. Data is collected by the ATLAS detector at $\sqrt{s} = 13$ TeV in 2015 and 2016, corresponding to an integrated luminosity of L = 36.2 fb$^{-1}$.

This work contributes to the improvement of b-jet reconstruction, enhances the performance of boosted Higgs identification, and thus provides better sensitivity of the Mono-H(bb) search.

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