2017 Fiscal Year Annual Research Report
Halo assembly bias systematics in interpreting cosmic acceleration
Publicly Offered Research
| Project Area | Why does the Universe accelerate? - Exhaustive study and challenge for the future - |
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| Project/Area Number |
16H01089
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| Research Institution | The University of Tokyo |
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Principal Investigator |
MORE Surhud 東京大学, カブリ数物連携宇宙研究機構, 准教授 (00646044)
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| Project Period (FY) |
2016-04-01 – 2018-03-31
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| Keywords | Splashback radius / Galaxy cluster / Assembly bias |
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| Outline of Annual Research Achievements |
The main goal of the project was to explore halo assembly bias and the edges of galaxy clusters in observations - called the splashback radius of the galaxy clusters. I have explored systematics with optical galaxy cluster detections after some of the reports of such systematics present in real galaxy cluster catalogs. Since no credible mock galaxy cluster catalogs existed to investigate this, I have worked on making such mock catalogs possible. I have found that due to optical cluster finding systematics, it is quite difficult to establish the presence of halo assembly bias in observations, and such systematics could also plague the inferred locations of the splashback radius. In FY 2017, I have further explored the detection of splashback radius using galaxy cluster samples detected using Xrays (ROSAT) or in the Sunyaev Zeldovich effect (Planck) instead of using the optically selected galaxy clusters. We made use of the PanStarrs galaxy catalog to perform galaxy cluster-galaxy cross-correlations. We have detected the splashback radius of galaxy clusters even when using this sample. We are in the process of comparison of these detected splashback radius with the expectation from cosmological simulations. In FY 2017, I have also worked on the Hyper Suprime Cam Survey weak lensing analysis. I have worked on establishing a pipeline to compute the galaxy galaxy weak lensing signal, to compute covariances for the measurements using mock galaxy catalogs, and establishing systematic requirements for galaxy shear catalogs, as well as estimating photometric redshift biases.
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| Research Progress Status |
29年度が最終年度であるため、記入しない。
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| Strategy for Future Research Activity |
29年度が最終年度であるため、記入しない。
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