Kazushi Iwasawa

Universitat de Barcelona

Experimental Sciences & Mathematics

Born and educated in Japan. After obtaining his PhD in astrophysics at Nagoya University, Nagoya, Japan, in 1995, he moved to Europe, working at the Institute of Astronomy, Cambridge in UK (1995-2005), at the Max Planck Institut für Extraterrestrische Physik in Germany (2005-2008), and at INAF-Osservatorio Astronomico di Bologna in Italy (2008-2009). In 2010 he joined ICREA, to work as an ICREA Research Professor at the Institut de Ciències del Cosmos (ICCUB). His main research area is X-ray astronomy on active galaxies and cosmic black holes.

Research interests

Kazushi Iwasawa works in the field of observational astronomy, mainly using X-ray observatories in space. His primary interest is in the formation and evolution of supermassive black holes powering active galaxies. These active galaxies are generally strong X-ray emitters, which makes X-ray observations a powerful probe of black hole activity even at great cosmological distances. He is involved in several multi-wavelength survey projects which attempt to establish cosmic evolution of the black hole activity and its relation to the galaxy formation. Currently most active collaborations include Great Observatories All-sky LIRG Survey (GOALS), for investigating properties of star formation and active black holes in lumimnous infrared galaxies with muti-wavelength datasets, the XMM-Newton deep survey in the Chandra Deep Field South for the evolution of active galactic nuclei using the deep X-ray observations, and the Subaru HyperSuprime Cam (HSC) survey for searching for the most distant quasars.

Selected publications

Iwasawa K, Vivian U, Mazzarella JM, Medling AM, Sanders DB & Evans AS 2018, ‘Testing a double AGN hypothesis for Mrk 273’, Astronomy & Astrophysics, 611, A71.

– Matsuoka Y, Iwasawa K, Onoue M, Kashikaw N, Strauss M et al, 2018, ‘Subaru High-z Exploration of Low-luminosity Quasars (SHELLQs). IV. Discovery of 41 Quasars and Luminous Galaxies at 5.7 < z < 6.9’, Astrophysical Journal Supplement Series, 237, 1, 5.

– Matsuoka Y, Strauss MA, Kashikawa N, Onoue M, Iwasawa K, Tang J-J, Lee C-H, Imanishi M, Nagao T et al, 2018, ‘Subaru High-z Exploration of Low-luminosity Quasars (SHELLQs). V. Quasar Luminosity Function and Contribution to Cosmic Reionization at z=6’, The Astrophysical Journal, 869, 150

– Torres-Albà N, Iwasawa K, Díaz-Santos T, Charmandaris V, Ricci C, Chu JK, Sanders DB, Armus L, Barcos-Muñoz L, Evans AS, Howell JH, Inami H, Linden ST, Medling AM, Privon GC, Vivian U & Yoon I 2018 ‘C-GOALS. II. Chandra observations of the lower luminosity sample of nearby luminous infrared galaxies in GOALS’, Astronomy and Astrophysics, 620, A140

Selected research activities

PhD examination panel for Elias Kammoun at SISSA (Italy)

Time allocation committees of NuSTAR Cycle 4 (NASA), and XMM-Neton AO-18 (ESA)

PI of oberving programs with Gran Telescopio Canarias (18A and 18B, total 66 hr) for optical spectroscopy of high-z quasars and with XMM-Newton (AO-17) of IRAS F00183-7111 (80 ks). Co-I of the Subaru intensive program 18B-21A for SHELLQs project (30 nights), 18B Subaru Service Time, and ESO VLT time (10 hr) for NuSTAR Cycle 4 (120 ks)