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arXiv · 1904.07747

Ly$α$ view around a z=2.84 hyperluminous QSO at a node of the cosmic web

Satoshi Kikuta·Yuichi Matsuda·Renyue Cen·Charles C. Steidel·Masafumi Yagi·Tomoki Hayashino·Masatoshi Imanishi·Yutaka Komiyama·Rieko Momose·Tomoki Saito
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Abstract

We report on the results of deep and wide-field (1.1 deg$^2$) narrow-band observations with Subaru/Hyper Suprime-Cam (HSC) of a field around a hyperluminous QSO (HLQSO), HS1549+1919, residing in a protocluster at $z=2.84$, to map the large-scale structure of Ly$α$ emitters (LAEs). One HSC pointing enables us to detect 3490 LAEs and 76 extended Ly$α$ blobs (LABs), probing diverse environments from voids to protoclusters. The HLQSO is found to be near the center of the protocluster, which corresponds to the intersection of $\sim$100 cMpc-scale structures of LAEs. LABs are basically distributed along the large-scale structure, with larger ones particularly clustered around the HLQSO, confirming a previously noted tendency of LABs to prefer denser environments. Moreover, the shapes of LABs near the HLQSO appear to be aligned with the large-scale structure. Finally, a deep Ly$α$ image reveals a diffuse Ly$α$ nebula along a filamentary structure with no luminous UV/sub-mm counterpart. We suggest that the diffuse nebula is due to a cold filament with high clumping factor illuminated by the QSO, with a required high clumpiness provided by unresolved residing halos of mass $\leq 10^{9-10}M_\odot$.

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Satoshi Kikuta, Yuichi Matsuda, Renyue Cen, Charles C. Steidel, Masafumi Yagi, Tomoki Hayashino, Masatoshi Imanishi, Yutaka Komiyama, Rieko Momose, Tomoki Saito. 2019-04-16. Ly$α$ view around a z=2.84 hyperluminous QSO at a node of the cosmic web. https://doi.org/10.1093/pasj%2Fpsz055

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