A SPectroscopic Survey of Biased Halos in the Reionization Era (ASPIRE): A First Look at the Rest-frame Optical Spectra of z > 6.5 Quasars Using JWST
Hennawi, Joseph F.; Shen, Yue; Strauss, Michael A.; Fan, Xiaohui; Jiang, Linhua; Trebitsch, Maxime; Colina, Luis; Cai, Zheng; Wu, Yunjing; Barth, Aaron J.; Walter, Fabian; Egami, Eiichi; Sun, Fengwu; Connor, Thomas; Jun, Hyunsung D.; Yang, Jinyi; Wang, Feige; Bañados, Eduardo; Liu, Weizhe; Li, Zihao; Onoue, Masafusa; Schindler, Jan-Torge; Bhowmick, Aklant K.; Bieri, Rebekka; Blecha, Laura; Bosman, Sarah; Champagne, Jaclyn B.; Costa, Tiago; Davies, Frederick B.; Decarli, Roberto; De Rosa, Gisella; Drake, Alyssa B.; Eilers, Anna-Christina; Evans, Analis E.; Farina, Emanuele Paolo; Habouzit, Melanie; Haiman, Zoltan; Jin, Xiangyu; Kakiichi, Koki; Khusanova, Yana; Kulkarni, Girish; Loiacono, Federica; Lupi, Alessandro; Mazzucchelli, Chiara; Pan, Zhiwei; Rojas-Ruiz, Sofía; Tee, Wei Leong; Trakhtenbrot, Benny; Venemans, Bram; Vestergaard, Marianne; Volonteri, Marta; Xie, Zhang-Liang; Yue, Minghao; Zhang, Haowen; Zhang, Huanian; Zou, Siwei
United States, Netherlands, Germany, China, Japan, Switzerland, Spain, Denmark, Italy, United Kingdom, South Korea, India, Chile, Israel, France
Abstract
Studies of rest-frame optical emission in quasars at z > 6 have historically been limited by the wavelengths accessible by ground-based telescopes. The James Webb Space Telescope (JWST) now offers the opportunity to probe this emission deep into the reionization epoch. We report the observations of eight quasars at z > 6.5 using the JWST/NIRCam Wide Field Slitless Spectroscopy as a part of the "A SPectroscopic survey of biased halos In the Reionization Era (ASPIRE)" program. Our JWST spectra cover the quasars' emission between rest frame ~4100 and 5100 Å. The profiles of these quasars' broad Hβ emission lines span a full width at half maximum from 3000 to 6000 km s-1. The Hβ-based virial black hole (BH) masses, ranging from 0.6 to 2.1 billion solar masses, are generally consistent with their Mg II-based BH masses. The new measurements based on the more reliable Hβ tracer thus confirm the existence of a billion solar-mass BHs in the reionization epoch. In the observed [O III] λ λ 4960,5008 doublets of these luminous quasars, broad components are more common than narrow core components (≤ 1200 km s-1), and only one quasar shows stronger narrow components than broad. Two quasars exhibit significantly broad and blueshifted [O III] emission, thought to trace galactic-scale outflows, with median velocities of -610 and -1430 km s-1 relative to the [C II] 158 μm line. All eight quasars show strong optical Fe II emission and follow the eigenvector 1 relations defined by low-redshift quasars. The entire ASPIRE program will eventually cover 25 quasars and provide a statistical sample for the studies of the BHs and quasar spectral properties.