Following the successful commissioning of the NEXT-100 detector, the NEXT collaboration is proud to share the first scientific results from the detector’s initial operation at 4 bar at the Laboratorio Subterráneo de Canfranc (LSC). Two new articles have just been released, marking a crucial milestone for the experiment.
The first major step in understanding the detector’s response involved a low-energy calibration campaign using 83mKr decays. The work (published in this article) focuses on characterizing the detector at low energies to generate precise maps of the detector’s light response for accurate event reconstruction and measure the energy scale and electron lifetime, as well as other operating conditions parameters. The results were excellent, achieving an energy resolution of 4.37% FWHM at 41.5 keV.
The collaboration moved to high-energy calibration using a 228Th source. The results were published in the second article, and confirm one of the most important features of the NEXT technology: its excellent energy resolution. The detector achieved an energy resolution of 0.90% FWHM for the photopeak of 208Tl at 2615 keV. When extrapolated using other peaks in the spectra to the Qββ energy of 136Xe (2458 keV) the resolution is 0.939% FWHM, squarely meeting the design goal of sub-percent resolution.
These results, obtained with the detector operating at 4 bar confirm that NEXT-100 is operating exceptionally well. With the detector’s performance validated, the collaboration looks forward to increasing the pressure to 10 bar in early 2026 and continue with the experimental program.