Searching for Protoclusters / Probabilistic Selection of z>6 Quasars: Initial Results from the First HSC SSP Data

[Speaker1]
Jun Toshikawa, D3, SOKENDAI, Mitaka(supervisor: Nobunari Kashikawa)
[Title1]
Searching for Protoclusters

[Speaker2]
Masafusa Onoue, M2, SOKENDAI, Mitaka(supervisor: Nobunari Kashikawa)
[Title2]
Probabilistic Selection of z>6 Quasars: Initial Results from the First HSC SSP Data
[Abstract]
I will present my high-z quasar selection method using SED fitting and its application to the first HSC-SSP data.
While it is a well-known problem that the classical quasar selection based on two colors suffers from contaminating sources such as brown dwarfs, photometric redshift with multi-color photometry is a complementary way to effectively isolate high-z quasars. Since photo-z for AGN has been less explored comparing with photo-z for galaxies, I have developed template SED fitting method by myself to construct the largest z>6 quasar sample with the HSC survey.
In this talk, I will show how our selection works on the existing quasar samples such as z>3 quasars in the COSMOS field, and then report the result of the first application to the HSC-SSP data products, which results in five z>6 quasar candidates including one possible highest-redshift (z_photo=7.3) quasar.