article published yes Feige Wang author Jaclyn B. Champagne author Jiamu Huang author Jinyi Yang author Joseph F. Hennawi author Xiaohui Fan author Haowen Zhang author Tiago Costa author Roberto Decarli author Melanie Habouzit author Fengwu Sun author Eduardo Bañados author Xiangyu Jin author Koki Kakiichi author Romain A. Meyer author Yunjing Wu author Silvia Belladitta author Laura Blecha author Sarah E.I. Bosman author Zheng Cai author Thomas Connor author Frederick B. Davies author Anna Christina Eilers author Zoltán Haiman author 7c006e8c-cc0d-11ee-8322-cb904ef76f360000-0003-3633-5403 Hyunsung D. Jun author Mingyu Li author Zihao Li author Weizhe Liu author Alessandro Lupi author Jianwei Lyu author Chiara Mazzucchelli author Masafusa Onoue author Elia Pizzati author Maria Pudoka author Sofía Rojas-Ruiz author Jan Torge Schindler author Yue Shen author Wei Leong Tee author Benny Trakhtenbrot author Maxime Trebitsch author Marianne Vestergaard author Marta Volonteri author Fabian Walter author Huanian Zhang author Siwei Zou author ZoHa department We present a systematic study of the environments of 25 luminous quasars at z > 6.5 from the ASPIRE program. Using JWST/NIRCam wide-field slitless spectroscopy data, we identified 487 galaxies at 5.3 ≲ z ≲ 7.0 exhibiting [O III] emission. Among these, 122 [O III] emitters lie within |Δvlos| < 1000 km s −1 of the quasars, corresponding to a ∼9.4-fold enhancement relative to the average galaxy density at other redshifts. Furthermore, we identified 16 [C II]-emitting galaxies at the quasar redshifts from Atacama Large Millimeter/submillimeter Array (ALMA) mosaic observations. A cross-correlation function analysis between quasars and [O III]+[C II] emitters yields a cross-correlation length of r 8.68 h cMpc 0 QG 0.55 = +0.51 1 and an autocorrelation of r 15.76 h cMpc 0 QQ 2.70 = +2.48 1 , indicating that z ∼ 7 quasars reside in dark matter halos with Mhalo 1012.27 0.26 M 0.21 = + and have a quasar lifetime of tQ 10 yr 7.05 1.01 0.95 = + . Notably, the number of [O III]-emitting galaxies at quasar redshifts varies significantly from field to field, ranging from 0 to 20, highlighting a diverse quasar environment. Remarkably, seven quasars trace significant galaxy overdensities (i.e., protoclusters), with δgal > 5 within a volume of V ∼ 500 cMpc3 . We also find that |Δvlos| increases rapidly toward smaller galaxy–quasar separations in protocluster fields, consistent with galaxy kinematics around extremely massive halos in cosmological simulations. By combining JWST and ALMA data, we reveal the complex and diverse environments of these early quasars, providing robust evidence that the earliest luminous quasars are effective tracers of galaxy overdensities, albeit with substantial field-to-field variation. https://research-explorer.ista.ac.at/download/22362/22377/2026_AstrophysicalJour_Wang.pdf application/pdfno IOP Publishing2026 eng 0004637X 15384357 2602.0497910.3847/1538-4357/ae7bfa 10061 F. Wang, J.B. Champagne, J. Huang, J. Yang, J.F. Hennawi, X. Fan, H. Zhang, T. Costa, R. Decarli, M. Habouzit, F. Sun, E. Bañados, X. Jin, K. Kakiichi, R.A. Meyer, Y. Wu, S. Belladitta, L. Blecha, S.E.I. Bosman, Z. Cai, T. Connor, F.B. Davies, A.C. Eilers, Z. Haiman, H.D. Jun, M. Li, Z. Li, W. Liu, A. Lupi, J. Lyu, C. Mazzucchelli, M. Onoue, E. Pizzati, M. Pudoka, S. Rojas-Ruiz, J.T. Schindler, Y. Shen, W.L. Tee, B. Trakhtenbrot, M. Trebitsch, M. Vestergaard, M. Volonteri, F. Walter, H. Zhang, S. Zou, Astrophysical Journal 1006 (2026). Wang, Feige, et al. “ASPIRE: The Environments and Dark Matter Halos of Luminous Quasars in the Epoch of Reionization.” <i>Astrophysical Journal</i>, vol. 1006, no. 1, 39, IOP Publishing, 2026, doi:<a href="https://doi.org/10.3847/1538-4357/ae7bfa">10.3847/1538-4357/ae7bfa</a>. Wang F, Champagne JB, Huang J, et al. ASPIRE: The environments and dark matter halos of luminous quasars in the epoch of reionization. <i>Astrophysical Journal</i>. 2026;1006(1). doi:<a href="https://doi.org/10.3847/1538-4357/ae7bfa">10.3847/1538-4357/ae7bfa</a> F. Wang <i>et al.</i>, “ASPIRE: The environments and dark matter halos of luminous quasars in the epoch of reionization,” <i>Astrophysical Journal</i>, vol. 1006, no. 1. IOP Publishing, 2026. Wang F, Champagne JB, Huang J, Yang J, Hennawi JF, Fan X, Zhang H, Costa T, Decarli R, Habouzit M, Sun F, Bañados E, Jin X, Kakiichi K, Meyer RA, Wu Y, Belladitta S, Blecha L, Bosman SEI, Cai Z, Connor T, Davies FB, Eilers AC, Haiman Z, Jun HD, Li M, Li Z, Liu W, Lupi A, Lyu J, Mazzucchelli C, Onoue M, Pizzati E, Pudoka M, Rojas-Ruiz S, Schindler JT, Shen Y, Tee WL, Trakhtenbrot B, Trebitsch M, Vestergaard M, Volonteri M, Walter F, Zhang H, Zou S. 2026. ASPIRE: The environments and dark matter halos of luminous quasars in the epoch of reionization. Astrophysical Journal. 1006(1), 39. Wang, Feige, Jaclyn B. Champagne, Jiamu Huang, Jinyi Yang, Joseph F. Hennawi, Xiaohui Fan, Haowen Zhang, et al. “ASPIRE: The Environments and Dark Matter Halos of Luminous Quasars in the Epoch of Reionization.” <i>Astrophysical Journal</i>. IOP Publishing, 2026. <a href="https://doi.org/10.3847/1538-4357/ae7bfa">https://doi.org/10.3847/1538-4357/ae7bfa</a>. Wang, F., Champagne, J. B., Huang, J., Yang, J., Hennawi, J. F., Fan, X., … Zou, S. (2026). ASPIRE: The environments and dark matter halos of luminous quasars in the epoch of reionization. <i>Astrophysical Journal</i>. IOP Publishing. <a href="https://doi.org/10.3847/1538-4357/ae7bfa">https://doi.org/10.3847/1538-4357/ae7bfa</a> 223622026-07-19T22:01:46Z2026-07-20T13:31:18Z