Electronic recoils in XENONnT

Dark Matter is one of the biggest mysteries in modern astroparticle physics. One of the ways to detect dark matter is through scattering, where a dark matter particle collides with an atomic nucleus, producing a measureable signa. A dark matter detector can potentially detect signals of WIMP-nucleus interactions and other exotic particles such as solar axions and axion-like particles.
One type of dark matter detector is a dual-phase xenon Time Projection Chamber (TPC). The XENONnT experiment, located at Laboratori Nazionali del Gran Sasso in Italy, is one such detector. The XENONnT Data Acquisition System (DAQ) is a system designed to acquire data constantly, with design criteria such as low energy threshold, low noise, low dead time, high data rates, dual gain readout, fast data processing, and a high-energy veto.
We present two separate results to validate the XENONnT Monte Carlo framework, the reconstruction of detector parameters g₁ and g₂, and the comparison of the background model of the first science run of XENONnT with a simulated dataset.
The most significant contribution to the ER background is from ²¹⁴Pb, which comes from the decay of ²²²Rn. The ²¹⁴Pb rate can be constrained by measuring the rate of various alpha decay from the ²²²Rn chain. The concentration of ²¹⁴Pb is determined to be between 0.74 and 1.62 micro Bq/kg.
We finally present the results of a solar axion search using the data of the first science run of XENONnT, with the detector response is modeled as analytical functions depending on, at most, six observables. The resulting limits on the axion couplings g_ae, and g_aγ are consistent with previous measurements.