Data-driven modeling of electron recoil nucleation in PICO 
C3F8
 bubble chambers
The PICO Collaboration wishes to thank SNOLAB and 
its staff for support through underground space, logistical 
and technical services. SNOLAB operations are supported 
by the Canada Foundation for Innovation and the Province 
of Ontario Ministry of Research and Innovation, with 
underground access provided by Vale at the Creighton 
mine site. We wish to acknowledge the support of the 
Natural Sciences and Engineering Research Council of 
Canada (NSERC) and the Canada Foundation for 
Innovation (CFI) for funding. We acknowledge the support 
from National Science Foundation (NSF) (Grants 
No. 0919526, No. 1506337, No. 1242637, No. 1205987, 
and No. 1806722). We acknowledge that this work is 
supported by the U.S. Department of Energy (DOE) Office 
of Science, Office of High Energy Physics (under Award 
No. DE-SC-0012161), by DGAPA-UNAM (PAPIIT 
No. IA100118) and Consejo Nacional de Ciencia y 
Tecnologia (CONACyT, M?exico, Grants No. 252167 and 
No. A1-S-8960), by the Department of Atomic Energy 
(DAE), Government of India, under the Centre for AstroParticle Physics II project (CAPP-II) at the Saha 
Institute of Nuclear Physics (SINP), European Regional 
Development Fund?Project ?Engineering Applications of 
Microworld Physics? (Project No. CZ.02.1.01/0.0/0.0/ 
16_019/0000766), and the Spanish Ministerio de Ciencia, 
Innovacion y Universidades (Red Consolider MultiDark, 
Grant No. FPA2017-90566-REDC). This work is partially 
supported by the Kavli Institute for Cosmological Physics at 
the University of Chicago through NSF Grant No. 1125897, 
and an endowment from the Kavli Foundation and its 
founder Fred Kavli. We also wish to acknowledge the 
support from Fermi National Accelerator Laboratory under 
Contract No. DE-AC02-07CH11359, and Pacific Northwest 
National Laboratory, which is operated by Battelle for the 
U.S. Department of Energy under Contract No. DE-AC05- 
76RL01830. We also thank Compute Canada [75] and the 
Center for Advanced Computing, ACENET, Calcul Qu?ebec, 
Compute Ontario, and WestGrid for computational support.