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July 8, 2026
Dear all,
On Wednesday, July 8th, we will have Yuichi Matsuda (NAOJ / MEXT) visiting DTU Space. They will be giving a special cake talk that day at 14:00. If you'd like to meet Yuichi, please reach out to Minju Lee.
MIRACLES (Mapping of Ionizing RAdiation on the Cosmic web with Ly-alpha Emission and Shadow)
We introduce an ongoing Subaru HSC/PFS program, MIRACLES.
Using ultra deep HSC Lyα imaging of the cosmic web toward the z = 3.09 SSA22 protocluster, we aim to simultaneously trace ionized HII gas (via Lyα emission) and neutral HI gas (via Lyα absorption) over a cosmological volume of 180 × 180 × 50 cMpc.
The goals of MIRACLES are to unveil
(1) the physical properties of gas filaments along the cosmic web, such as their width, length, mass, and ionizing radiation field,
(2) the connection between the cosmic web and galaxy and black hole growth, and
(3) the role of the cosmic web in cluster formation.
We have completed 100 hours of HSC observations and obtained the first convincing map of Lyα filaments on cosmological scales. Follow-up 30-hour PFS observations are scheduled for July.
