Isaac J. Arnquist
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Research Subjects
Research Interests
Isaac J. Arnquist has a total of 602 co-authors. Here are the top co-authors by number of shared publications:
- Eric W. Hoppe
Pacific Northwest National Laboratory
9 shared publications - Khadouja Harouaka
Pacific Northwest National Laboratory, Richland, Washington 99352, United States
6 shared publications - Maria Laura di Vacri
Pacific Northwest National Laboratory
6 shared publications - A. Castillo
Donostia International Physics Center, BERC Basque Excellence Research Centre
5 shared publications - A. Larumbe
Universidad del Pais Vasco (UPV/EHU), Centro de Innovación en Química Avánzada (ORFEO-CINQA)
5 shared publications - A. P. Marques
University of Coimbra
5 shared publications
Latest Publications
- Open Access
- 10 September 2026
- Published by Springer Nature in The European Physical Journal C
- Vol. 86 (9) , 1057
Demonstration of sub-percent energy resolution in the NEXT-100 detector
NEXT-100 is a high-pressure xenon time projection chamber with electroluminescent amplification, designed to operate with up to $$\sim $$ 70.5 kg at 13.5 bar. It is the most recent detector developed by the NEXT collaboration to search for the neutrinoless double-beta decay ( $$\beta \beta 0\nu $$ ) of $$ ^{136}\mathrm Xe$$ . The NEXT gas TPC technology offers the best energy resolution near the Q-value of the decay ( $$Q_{\beta \beta }$$ = 2458 keV) among xenon detectors, which is set by design to be <1% FWHM. We report here the high-energy calibration of the detector using a $$ ^{228}\textrm{Th}$$ source, demonstrating excellent linear response and an energy resolution of $$(0.90 \pm 0.02)\%$$ FWHM at the $$^{208}$$ Tl photopeak (2615 keV). This performance extrapolates to a resolution at the double-beta decay end-point of $$R(Q_{\beta \beta }) = (0.93 \pm 0.02)\%$$ FWHM, confirming the detector’s capability for precision energy measurement in the search for $$\beta \beta 0\nu $$ .- 10 September 2026
- Published by Springer Nature in The European Physical Journal C
- Vol. 86 (9) , 1057
Open AccessDemonstration of sub-percent energy resolution in the NEXT-100 detector
NEXT-100 is a high-pressure xenon time projection chamber with electroluminescent amplification, designed to operate with up to $$\sim $$ 70.5 kg at 13.5 bar. It is the most recent detector developed by the NEXT collaboration to search for the neutrinoless double-beta decay ( $$\beta \beta 0\nu $$ ) of $$ ^{136}\mathrm Xe$$ . The NEXT gas TPC technology offers the best energy resolution near the Q-value of the decay ( $$Q_{\beta \beta }$$ = 2458 keV) among xenon detectors, which is set by design to be <1% FWHM. We report here the high-energy calibration of the detector using a $$ ^{228}\textrm{Th}$$ source, demonstrating excellent linear response and an energy resolution of $$(0.90 \pm 0.02)\%$$ FWHM at the $$^{208}$$ Tl photopeak (2615 keV). This performance extrapolates to a resolution at the double-beta decay end-point of $$R(Q_{\beta \beta }) = (0.93 \pm 0.02)\%$$ FWHM, confirming the detector’s capability for precision energy measurement in the search for $$\beta \beta 0\nu $$ . - Open Access
- 1 July 2026
- Published by Springer Nature in The European Physical Journal C
- Vol. 86 (7)
First results of the NEXT-100 detector using 83mKr decays
The NEXT collaboration is investigating the double beta decay of $$ ^{136}\mathrm Xe$$ using high-pressure gas electroluminescent time projection chambers, which provide excellent energy resolution together with a robust topological signature. Operating at the Laboratorio Subterráneo de Canfranc (LSC) and building on the success of the NEXT-White detector, the NEXT-100 apparatus began commissioning in May 2024 and started operation with xenon at a pressure of 4 bar in October 2024. We report here the first results obtained with NEXT-100 using low-energy calibration data from $$^{83\text {m}}\textrm{Kr}$$ decays, which allow mapping of the detector response in the active volume and monitoring of its stability over time. After homogenizing the light response, we achieve an energy resolution of 4.37% FWHM at 41.5 keV for $$^{83\text {m}}\textrm{Kr}$$ point-like energy deposits contained in a radius of 425 mm. In a fiducial region representing the operating conditions of NEXT-100 at 10 bar we obtain an improved energy resolution of 4.16% FWHM. These results are in good agreement with that obtained in NEXT-White, and an $$E^{-1/2}$$ extrapolation to $$Q_{\beta \beta }$$ yields an energy resolution close to 0.5% FWHM, well below the 1% FWHM design target.- 1 July 2026
- Published by Springer Nature in The European Physical Journal C
- Vol. 86 (7)
Open AccessFirst results of the NEXT-100 detector using 83mKr decays
The NEXT collaboration is investigating the double beta decay of $$ ^{136}\mathrm Xe$$ using high-pressure gas electroluminescent time projection chambers, which provide excellent energy resolution together with a robust topological signature. Operating at the Laboratorio Subterráneo de Canfranc (LSC) and building on the success of the NEXT-White detector, the NEXT-100 apparatus began commissioning in May 2024 and started operation with xenon at a pressure of 4 bar in October 2024. We report here the first results obtained with NEXT-100 using low-energy calibration data from $$^{83\text {m}}\textrm{Kr}$$ decays, which allow mapping of the detector response in the active volume and monitoring of its stability over time. After homogenizing the light response, we achieve an energy resolution of 4.37% FWHM at 41.5 keV for $$^{83\text {m}}\textrm{Kr}$$ point-like energy deposits contained in a radius of 425 mm. In a fiducial region representing the operating conditions of NEXT-100 at 10 bar we obtain an improved energy resolution of 4.16% FWHM. These results are in good agreement with that obtained in NEXT-White, and an $$E^{-1/2}$$ extrapolation to $$Q_{\beta \beta }$$ yields an energy resolution close to 0.5% FWHM, well below the 1% FWHM design target. - Top Cited PapersOpen Access
- 5 February 2026
- Published by Springer Nature in The European Physical Journal C
- Vol. 86 (2) , 114
The NEXT-100 Detector
The NEXT collaboration is dedicated to the study of double beta decays of $$^{136}$$ Xe using a high-pressure gas electroluminescent time projection chamber. This advanced technology combines exceptional energy resolution ( $$\le 1\%$$ FWHM at the $$Q_{\beta \beta }$$ value of the neutrinoless double beta decay) and powerful topological event discrimination. Building on the achievements of the NEXT-White detector, the NEXT-100 detector started taking data at the Laboratorio Subterráneo de Canfranc (LSC) in May of 2024. Designed to operate with xenon gas at 13.5 bar, NEXT-100 consists of a time projection chamber where the energy and the spatial pattern of the ionising particles in the detector are precisely retrieved using two sensor planes (one with photo-multiplier tubes and the other with silicon photo-multipliers). The detector has been operating at stable conditions using argon and xenon gases at $$\sim $$ 4 bar and drift fields of $$74\hbox { V cm}^{-1}$$ and $$118\hbox { V cm}^{-1}$$ , respectively. Alpha decays from the $$^{222}$$ Rn chain have been used to test and monitor the stability of the detector, showing a constant electron lifetime in the drift volume. In this paper, in addition to reporting the results of the commissioning run, we provide a detailed description of the NEXT-100 detector, describe its assembly, and present the current estimation of the radiopurity budget.- 5 February 2026
- Published by Springer Nature in The European Physical Journal C
- Vol. 86 (2) , 114
Top Cited PapersOpen AccessThe NEXT-100 Detector
The NEXT collaboration is dedicated to the study of double beta decays of $$^{136}$$ Xe using a high-pressure gas electroluminescent time projection chamber. This advanced technology combines exceptional energy resolution ( $$\le 1\%$$ FWHM at the $$Q_{\beta \beta }$$ value of the neutrinoless double beta decay) and powerful topological event discrimination. Building on the achievements of the NEXT-White detector, the NEXT-100 detector started taking data at the Laboratorio Subterráneo de Canfranc (LSC) in May of 2024. Designed to operate with xenon gas at 13.5 bar, NEXT-100 consists of a time projection chamber where the energy and the spatial pattern of the ionising particles in the detector are precisely retrieved using two sensor planes (one with photo-multiplier tubes and the other with silicon photo-multipliers). The detector has been operating at stable conditions using argon and xenon gases at $$\sim $$ 4 bar and drift fields of $$74\hbox { V cm}^{-1}$$ and $$118\hbox { V cm}^{-1}$$ , respectively. Alpha decays from the $$^{222}$$ Rn chain have been used to test and monitor the stability of the detector, showing a constant electron lifetime in the drift volume. In this paper, in addition to reporting the results of the commissioning run, we provide a detailed description of the NEXT-100 detector, describe its assembly, and present the current estimation of the radiopurity budget. - 9 January 2026
- Published by American Physical Society (APS) in Physical Review C
- Vol. 113 (1)
Enhanced sensitivity to trace U 238 impurity of sapphire via coincidence neutron activation analysis
- 9 January 2026
- Published by American Physical Society (APS) in Physical Review C
- Vol. 113 (1)
Enhanced sensitivity to trace U 238 impurity of sapphire via coincidence neutron activation analysis
- Open Access
- 28 August 2025
- Published by Springer Nature in The European Physical Journal C
- Vol. 85 (8) , 1-9
Performance of an optical TPC Geant4 simulation with opticks GPU-accelerated photon propagation
We investigate the performance of , a 7.5 GPU-accelerated photon propagation tool compared with a single-threaded simulation. We compare the simulations using an improved model of the gaseous time projection chamber. Performance results suggest that improves simulation speeds by between $$58.47\pm {0.02}$$ and $$181.39\pm {0.28}$$ times relative to a CPU-only simulation and these results vary between different types of GPU and CPU. A detailed comparison shows that the number of detected photons, along with their times and wavelengths, are in good agreement between and .- 28 August 2025
- Published by Springer Nature in The European Physical Journal C
- Vol. 85 (8) , 1-9
Open AccessPerformance of an optical TPC Geant4 simulation with opticks GPU-accelerated photon propagation
We investigate the performance of , a 7.5 GPU-accelerated photon propagation tool compared with a single-threaded simulation. We compare the simulations using an improved model of the gaseous time projection chamber. Performance results suggest that improves simulation speeds by between $$58.47\pm {0.02}$$ and $$181.39\pm {0.28}$$ times relative to a CPU-only simulation and these results vary between different types of GPU and CPU. A detailed comparison shows that the number of detected photons, along with their times and wavelengths, are in good agreement between and . - Open Access
Ultra-pure Nickel for Structural Components of Low-Radioactivity Instruments
The next generation of rare-event search experiments in nuclear and particle physics demand structural materials combining exceptional mechanical strength with ultra-low levels of radioactive contamination. This study evaluates chemical vapor deposition (CVD) nickel as a candidate structural material for such applications. Manufacturer-supplied CVD Ni grown on aluminum substrates underwent tensile testing before and after welding alongside standard Ni samples. CVD Ni exhibited a planar tensile strength of ~600 MPa, significantly surpassing standard nickel. However, welding and heat treatment were found to reduce the tensile strength to levels comparable to standard Ni, with observed porosity in the welds likely contributing to this reduction. Material assay via inductively coupled plasma mass spectrometry (ICP-MS) employing isotope-dilution produced measured bulk concentration of 232-Th, 238-U, and nat-K at the levels of ~70 ppq, <100 ppq, and ~900 ppt, respectively, which is the lowest reported in nickel. Surface-etch profiling uncovered higher concentrations of these contaminants extending ~10 micrometer beneath the surface, likely associated with the aluminum growth substrate. The results reported are compared to the one other well documented usage of CVD Ni in a low radioactive background physics research experiment and a discussion is provided on how the currently reported results may arise from changes in CVD fabrication or testing process. These results establish CVD Ni as a promising low-radioactivity structural material, while outlining the need for further development in welding and surface cleaning techniques to fully realize its potential in large-scale, low radioactive background rare-event search experiments.
Open AccessUltra-pure Nickel for Structural Components of Low-Radioactivity Instruments
The next generation of rare-event search experiments in nuclear and particle physics demand structural materials combining exceptional mechanical strength with ultra-low levels of radioactive contamination. This study evaluates chemical vapor deposition (CVD) nickel as a candidate structural material for such applications. Manufacturer-supplied CVD Ni grown on aluminum substrates underwent tensile testing before and after welding alongside standard Ni samples. CVD Ni exhibited a planar tensile strength of ~600 MPa, significantly surpassing standard nickel. However, welding and heat treatment were found to reduce the tensile strength to levels comparable to standard Ni, with observed porosity in the welds likely contributing to this reduction. Material assay via inductively coupled plasma mass spectrometry (ICP-MS) employing isotope-dilution produced measured bulk concentration of 232-Th, 238-U, and nat-K at the levels of ~70 ppq, <100 ppq, and ~900 ppt, respectively, which is the lowest reported in nickel. Surface-etch profiling uncovered higher concentrations of these contaminants extending ~10 micrometer beneath the surface, likely associated with the aluminum growth substrate. The results reported are compared to the one other well documented usage of CVD Ni in a low radioactive background physics research experiment and a discussion is provided on how the currently reported results may arise from changes in CVD fabrication or testing process. These results establish CVD Ni as a promising low-radioactivity structural material, while outlining the need for further development in welding and surface cleaning techniques to fully realize its potential in large-scale, low radioactive background rare-event search experiments.
- Open Access
- 15 July 2025
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2025 (7) , 1-22
Reconstructing neutrinoless double beta decay event kinematics in a xenon gas detector with vertex tagging
A bstract: If neutrinoless double beta decay is discovered, the next natural step would be understanding the lepton number violating physics responsible for it. Several alternatives exist beyond the exchange of light neutrinos. Some of these mechanisms can be distinguished by measuring phase-space observables, namely the opening angle cos θ among the two decay electrons, and the electron energy spectra, T 1 and T 2 . In this work, we study the statistical accuracy and precision in measuring these kinematic observables in a future xenon gas detector with the added capability to precisely locate the decay vertex. For realistic detector conditions (a gas pressure of 10 bar and spatial resolution of 4 mm), we find that the average $$ \overline{\cos\ \theta } $$ and $$ \overline{T_1} $$ values can be reconstructed with a precision of 0.19 and 110 keV, respectively, assuming that only 10 neutrinoless double beta decay events are detected.- 15 July 2025
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2025 (7) , 1-22
Open AccessReconstructing neutrinoless double beta decay event kinematics in a xenon gas detector with vertex tagging
A bstract: If neutrinoless double beta decay is discovered, the next natural step would be understanding the lepton number violating physics responsible for it. Several alternatives exist beyond the exchange of light neutrinos. Some of these mechanisms can be distinguished by measuring phase-space observables, namely the opening angle cos θ among the two decay electrons, and the electron energy spectra, T 1 and T 2 . In this work, we study the statistical accuracy and precision in measuring these kinematic observables in a future xenon gas detector with the added capability to precisely locate the decay vertex. For realistic detector conditions (a gas pressure of 10 bar and spatial resolution of 4 mm), we find that the average $$ \overline{\cos\ \theta } $$ and $$ \overline{T_1} $$ values can be reconstructed with a precision of 0.19 and 110 keV, respectively, assuming that only 10 neutrinoless double beta decay events are detected. - Open Access
- 1 September 2024
- Published by IOP Publishing in Journal of Instrumentation
- Vol. 19 (09) , P09001
Abatement of ionizing radiation for superconducting quantum devices
Ionizing radiation has been shown to reduce the performance of superconducting quantum circuits. In this report, we evaluate the expected contributions of different sources of ambient radioactivity for typical superconducting qubit experiment platforms. Our assessment of radioactivity inside a typical cryostat highlights the importance of selecting appropriate materials for the experiment components nearest to qubit devices, such as packaging and electrical interconnects. We present a shallow underground facility (30-meter water equivalent) to reduce the flux of cosmic rays and a lead shielded cryostat to abate the naturally occurring radiogenic gamma-ray flux in the laboratory environment. We predict that superconducting qubit devices operated in this facility could experience a reduced rate of correlated multi-qubit errors by a factor of approximately 20 relative to the rate in a typical above-ground, unshielded facility. Finally, we outline overall design improvements that would be required to further reduce the residual ionizing radiation rate, down to the limit of current generation direct detection dark matter experiments.
- 1 September 2024
- Published by IOP Publishing in Journal of Instrumentation
- Vol. 19 (09) , P09001
Open AccessAbatement of ionizing radiation for superconducting quantum devices
Ionizing radiation has been shown to reduce the performance of superconducting quantum circuits. In this report, we evaluate the expected contributions of different sources of ambient radioactivity for typical superconducting qubit experiment platforms. Our assessment of radioactivity inside a typical cryostat highlights the importance of selecting appropriate materials for the experiment components nearest to qubit devices, such as packaging and electrical interconnects. We present a shallow underground facility (30-meter water equivalent) to reduce the flux of cosmic rays and a lead shielded cryostat to abate the naturally occurring radiogenic gamma-ray flux in the laboratory environment. We predict that superconducting qubit devices operated in this facility could experience a reduced rate of correlated multi-qubit errors by a factor of approximately 20 relative to the rate in a typical above-ground, unshielded facility. Finally, we outline overall design improvements that would be required to further reduce the residual ionizing radiation rate, down to the limit of current generation direct detection dark matter experiments.