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

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 \(\sim\) 4100 and 5100 Å. The profiles of these quasars' broad H\(\beta\) emission lines span a FWHM from 3000 to 6000 \(\rm{km~s^{-1}}\). The H\(\beta\)-based virial black hole (BH) masses, ranging from 0.6 to 2.1 billion solar masses, are generally consistent with their MgII-based BH masses. The new measurements based on the more reliable H\(\beta\) tracer thus confirm the existence of billion solar-mass BHs in the reionization epoch. In the observed [OIII] \(\lambda\lambda\)4960,5008 doublets of these luminous quasars, broad components are more common than narrow core components (\(\le~1200~\rm{km~s^{-1}}\)), and only one quasar shows stronger narrow components than broad. Two quasars exhibit significantly broad and blueshifted [OIII] emission, thought to trace galactic-scale outflows, with median velocities of \(-610~\rm{km~s^{-1}}\) and \(-1430~\rm{km~s^{-1}}\) relative to the [CII] \(158\,\mu\)m line. All eight quasars show strong optical FeII 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.