The Atacama Cosmology Telescope: A Measurement of the DR6 CMB Lensing Power Spectrum and its Implications for Structure Growth
Creators: name: Qu, Frank J.
name: Sherwin, Blake D.
name: Madhavacheril, Mathew S.
name: Han, Dongwon
name: Crowley, Kevin T.
name: Abril-Cabezas, Irene
name: Ade, Peter A. R.
name: Aiola, Simone
name: Alford, Tommy
name: Amiri, Mandana
name: Amodeo, Stefania
name: An, Rui
name: Atkins, Zachary
name: Austermann, Jason E.
name: Battaglia, Nicholas
name: Battistelli, Elia Stefano
name: Beall, James A.
name: Bean, Rachel
name: Beringue, Benjamin
name: Bhandarkar, Tanay
name: Biermann, Emily
name: Bolliet, Boris
name: Bond, J Richard
name: Cai, Hongbo
name: Calabrese, Erminia
name: Calafut, Victoria
name: Capalbo, Valentina
name: Carrero, Felipe
name: Carron, Julien
name: Challinor, Anthony
name: Chesmore, Grace E.
name: Cho, Hsiao-mei
name: Choi, Steve K.
name: Clark, Susan E.
name: Rosado, Rodrigo Córdova
name: Cothard, Nicholas F.
name: Coughlin, Kevin
name: Coulton, William
name: Dalal, Roohi
name: Darwish, Omar
name: Devlin, Mark J.
name: Dicker, Simon
name: Doze, Peter
name: Duell, Cody J.
name: Duff, Shannon M.
name: Duivenvoorden, Adriaan J.
name: Dunkley, Jo
name: Dünner, Rolando
name: Fanfani, Valentina
name: Fankhanel, Max
name: Farren, Gerrit
name: Ferraro, Simone
name: Freundt, Rodrigo
name: Fuzia, Brittany
name: Gallardo, Patricio A.
name: Garrido, Xavier
name: Gluscevic, Vera
name: Golec, Joseph E.
name: Guan, Yilun
name: Halpern, Mark
name: Harrison, Ian
name: Hasselfield, Matthew
name: Healy, Erin
name: Henderson, Shawn
name: Hensley, Brandon
name: Hervías-Caimapo, Carlos
name: Hill, J. Colin
name: Hilton, Gene C.
name: Hilton, Matt
name: Hincks, Adam D.
name: Hložek, Renée
name: Ho, Shuay-Pwu Patty
name: Huber, Zachary B.
name: Hubmayr, Johannes
name: Huffenberger, Kevin M.
name: Hughes, John P.
name: Irwin, Kent
name: Isopi, Giovanni
name: Jense, Hidde T.
name: Keller, Ben
name: Kim, Joshua
name: Knowles, Kenda
name: Koopman, Brian J.
name: Kosowsky, Arthur
name: Kramer, Darby
name: Kusiak, Aleksandra
name: La Posta, Adrien
name: Lague, Alex
name: Lakey, Victoria
name: Lee, Eunseong
name: Li, Zack
name: Li, Yaqiong
name: Limon, Michele
name: Lokken, Martine
name: Louis, Thibaut
name: Lungu, Marius
name: MacCrann, Niall
name: MacInnis, Amanda
name: Maldonado, Diego
name: Maldonado, Felipe
name: Mallaby-Kay, Maya
name: Marques, Gabriela A.
name: McMahon, Jeff
name: Mehta, Yogesh
name: Menanteau, Felipe
name: Moodley, Kavilan
name: Morris, Thomas W.
name: Mroczkowski, Tony
name: Naess, Sigurd
name: Namikawa, Toshiya
name: Nati, Federico
name: Newburgh, Laura
name: Nicola, Andrina
name: Niemack, Michael D.
name: Nolta, Michael R.
name: Orlowski-Scherer, John
name: Page, Lyman A.
name: Pandey, Shivam
name: Partridge, Bruce
name: Prince, Heather
name: Puddu, Roberto
name: Radiconi, Federico
name: Robertson, Naomi
name: Rojas, Felipe
name: Sakuma, Tai
name: Salatino, Maria
name: Schaan, Emmanuel
name: Schmitt, Benjamin L.
name: Sehgal, Neelima
name: Shaikh, Shabbir
name: Sierra, Carlos
name: Sievers, Jon
name: Sifón, Cristóbal
name: Simon, Sara
name: Sonka, Rita
name: Spergel, David N.
name: Staggs, Suzanne T.
name: Storer, Emilie
name: Switzer, Eric R.
name: Tampier, Niklas
name: Thornton, Robert
name: Trac, Hy
name: Treu, Jesse
name: Tucker, Carole
name: Ulluom, Joel
name: Vale, Leila R.
name: Van Engelen, Alexander
name: Van Lanen, Jeff
name: van Marrewijk, Joshiwa
name: Vargas, Cristian
name: Vavagiakis, Eve M.
name: Wagoner, Kasey
name: Wang, Yuhan
name: Wenzl, Lukas
name: Wollack, Edward J.
name: Xu, Zhilei
name: Zago, Fernando
name: Zhang, Kaiwen
Publisher: name: arXiv
Year: 2023
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: We present new measurements of cosmic microwave background (CMB) lensing over $9400$ sq. deg. of the sky. These lensing measurements are derived from the Atacama Cosmology Telescope (ACT) Data Release 6 (DR6) CMB dataset, which consists of five seasons of ACT CMB temperature and polarization observations. We determine the amplitude of the CMB lensing power spectrum at $2.3\%$ precision ($43σ$ significance) using a novel pipeline that minimizes sensitivity to foregrounds and to noise properties. To ensure our results are robust, we analyze an extensive set of null tests, consistency tests, and systematic error estimates and employ a blinded analysis framework. The baseline spectrum is well fit by a lensing amplitude of $A_{\mathrm{lens}}=1.013\pm0.023$ relative to the Planck 2018 CMB power spectra best-fit $Λ$CDM model and $A_{\mathrm{lens}}=1.005\pm0.023$ relative to the $\text{ACT DR4} + \text{WMAP}$ best-fit model. From our lensing power spectrum measurement, we derive constraints on the parameter combination $S^{\mathrm{CMBL}}_8 \equiv σ_8 \left({Ω_m}/{0.3}\right)^{0.25}$ of $S^{\mathrm{CMBL}}_8= 0.818\pm0.022$ from ACT DR6 CMB lensing alone and $S^{\mathrm{CMBL}}_8= 0.813\pm0.018$ when combining ACT DR6 and Planck NPIPE CMB lensing power spectra. These results are in excellent agreement with $Λ$CDM model constraints from Planck or $\text{ACT DR4} + \text{WMAP}$ CMB power spectrum measurements. Our lensing measurements from redshifts $z\sim0.5$--$5$ are thus fully consistent with $Λ$CDM structure growth predictions based on CMB anisotropies probing primarily $z\sim1100$. We find no evidence for a suppression of the amplitude of cosmic structure at low redshifts
description: 45+22 pages, 50 figures. v2 matches with published version in ApJ. Cosmological likelihood data and lensing maps are here: https://lambda.gsfc.nasa.gov/product/act/actadv_prod_table.html ; likelihood software is here: https://github.com/ACTCollaboration/act_dr6_lenslike . Also see companion papers Madhavacheril et al and MacCrann et al