The University of Tokyo · 물리·천문학
요시아키 온오 교수의 연구실은 원거리 은하, 특히 고적색도 은하와 라이만 알파 에미터(Lyman-alpha emitters)의 성질을 중심으로 연구를 진행합니다. 주로 허블 및 제임스 웨버 우주망원경(JWST)을 활용한 깊은 적외선 및 적외외선 관측을 통해 고적색도 은하의 형성과 진화, 별성분, 크기 및 구조를 분석합니다. 특히 고적색도 은하의 라이만 알파 방출선 특성과 별집단의 퇄도를 정량적으로 추론하는 데에 전문성을 기르고 있습니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
We present the results of our ultra-deep Keck/DEIMOS spectroscopy of z-dropout galaxies in the SDF and GOODS-N. For 3 out of 11 objects, we detect an emission line at ~ 1um with a signal-to-noise ratio of ~ 10. The lines show asymmetric profiles with high weighted skewness values, consistent with being Lya, yielding redshifts of z=7.213, 6.965, and 6.844. Specifically, we confirm the z=7.213 object in two independent DEIMOS runs with different spectroscopic configurations. The z=6.965 object is
We investigate the stellar populations of Lyman alpha emitters (LAEs) at z=5.7 and 6.6 in a 0.65 deg^2 sky of the Subaru/XMM-Newton Deep Survey (SXDS) Field, using deep images taken with Subaru/Suprime-Cam, UKIRT/WFCAM, and Spitzer/IRAC. We produce stacked multiband images at each redshift from 165 (z=5.7) and 91 (z=6.6) IRAC-undetected objects, to derive typical spectral energy distributions (SEDs) of z~6-7 LAEs for the first time. The stacked LAEs have as blue UV continua as the HST/WFC3 z-dro
We investigate the stellar populations of Ly emitters (LAEs) at z = 3.1 and 3.7 in 0.65 deg 2 of the Subaru/XMM-Newton Deep Field, based on rest-frame ultraviolet-to-optical photometry obtained from the Subaru/XMM-Newton Deep Survey, the UKIRT Infrared Deep Sky Survey/ Ultra Deep Survey (UKIDSS/UDS), and the Spitzer legacy survey of the UKIDSS/UDS. Among a total of 302 LAEs (224 for z = 3.1 and 78 for z = 3.7), only 11 are detected in the K band, i.e. brighter than K(3 ) = 24.1 mag. Eight of the
Abstract We present morphologies of galaxies at z ≳ 9 resolved by JWST/NIRCam 2–5 μ m imaging. Our sample consists of 22 galaxy candidates identified by stringent dropout and photo- z criteria in GLASS, CEERS, SMACS J0723, and Stephan’s Quintet flanking fields, one of which has been spectroscopically identified at z = 11.44. We perform surface brightness (SB) profile fitting with GALFIT for six bright galaxies with a signal-to-noise ratio = 10–40 on an individual basis and for stacked faint gala
We analyze the redshift- and luminosity-dependent sizes of dropout galaxy candidates in the redshift range z â¼ 7-12 using deep images from the 2012 Hubble Ultra Deep Field (UDF12) campaign, which offers two advantages over that used in earlier work. First, we utilize the increased signal-to-noise ratio offered by the UDF12 imaging to provide improved measurements for known galaxies at z â 6.5-8 in the HUDF. Second, because the UDF12 data have allowed the construction of the first robust gala
