Kang Ma, Xiaohu Liu, Wei Zhao, Songling Huang, Shisong Li
A high-precision current source, capable of supporting weighing measurements with a relative uncertainty at the $10^{-9}$ level, is essential for Kibble balance experiments. However, most current sources utilized in Kibble balances to date are homemade and not commercially available. In this paper, we introduce a digital-feedback, two-stage current source designed for the Tsinghua tabletop Kibble balance, relying solely on commercially available sources and voltmeters. A high-resolution, small-range current source is employed to digitally compensate for current output fluctuations from a large-range current source. Experimental tests show the proposal can offer an easy realization of a current source with nA/A stability to support Kibble balance measurements.
{"title":"A Bi-polar Current Source with High Short-term Stability for Tsinghua Tabletop Kibble Balance","authors":"Kang Ma, Xiaohu Liu, Wei Zhao, Songling Huang, Shisong Li","doi":"arxiv-2408.16405","DOIUrl":"https://doi.org/arxiv-2408.16405","url":null,"abstract":"A high-precision current source, capable of supporting weighing measurements\u0000with a relative uncertainty at the $10^{-9}$ level, is essential for Kibble\u0000balance experiments. However, most current sources utilized in Kibble balances\u0000to date are homemade and not commercially available. In this paper, we\u0000introduce a digital-feedback, two-stage current source designed for the\u0000Tsinghua tabletop Kibble balance, relying solely on commercially available\u0000sources and voltmeters. A high-resolution, small-range current source is\u0000employed to digitally compensate for current output fluctuations from a\u0000large-range current source. Experimental tests show the proposal can offer an\u0000easy realization of a current source with nA/A stability to support Kibble\u0000balance measurements.","PeriodicalId":501374,"journal":{"name":"arXiv - PHYS - Instrumentation and Detectors","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142213808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Vojtech Vanecek, Robert Kral, Katerina Krehlikova, Romana Kuverkova, Vladimir Babin, Petra Zemenova, Jan Rohlicek, Zuzana Malkova, Terezia Jurkovicova, Martin Nikl
Novel red-emitting scintillator Li$_2$MnCl$_4$ is proposed as a candidate for thermal neutron detection. It features high Li content, low density, low effective atomic number, and emission in red-NIR region. These characteristics make it an interesting candidate for long distance neutron detection in harsh enviroments e. g. decomisioning of nuclear powerplants. The absorption spectrum is thoroughly investigated in the scope of Tanabe-Sugano diagram. Luminescence mechanism in the undoped Li$_2$MnCl$_4$ is studied in depth. Doping by Eu$^{2+}$ and Ce$^{3+}$ is introduced as a trial to improve the scintillation efficiency. We show in the Eu$^{2+}$ and Ce$^{3+}$ doped Li$_2$MnCl$_4$ that luminescence mechanism involves energy transfer from the dopants to Mn$^{2+}$, and propose the local lattice distortion around the dopant and a possible charge compensation mechanisms.
{"title":"Li$_2$MnCl$_4$ single crystal: new candidate for red-emitting neutron scintillator","authors":"Vojtech Vanecek, Robert Kral, Katerina Krehlikova, Romana Kuverkova, Vladimir Babin, Petra Zemenova, Jan Rohlicek, Zuzana Malkova, Terezia Jurkovicova, Martin Nikl","doi":"arxiv-2408.16178","DOIUrl":"https://doi.org/arxiv-2408.16178","url":null,"abstract":"Novel red-emitting scintillator Li$_2$MnCl$_4$ is proposed as a candidate for\u0000thermal neutron detection. It features high Li content, low density, low\u0000effective atomic number, and emission in red-NIR region. These characteristics\u0000make it an interesting candidate for long distance neutron detection in harsh\u0000enviroments e. g. decomisioning of nuclear powerplants. The absorption spectrum\u0000is thoroughly investigated in the scope of Tanabe-Sugano diagram. Luminescence\u0000mechanism in the undoped Li$_2$MnCl$_4$ is studied in depth. Doping by\u0000Eu$^{2+}$ and Ce$^{3+}$ is introduced as a trial to improve the scintillation\u0000efficiency. We show in the Eu$^{2+}$ and Ce$^{3+}$ doped Li$_2$MnCl$_4$ that\u0000luminescence mechanism involves energy transfer from the dopants to Mn$^{2+}$,\u0000and propose the local lattice distortion around the dopant and a possible\u0000charge compensation mechanisms.","PeriodicalId":501374,"journal":{"name":"arXiv - PHYS - Instrumentation and Detectors","volume":"117 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142213812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The Solenoidal Large Intensity Device (SoLID) is a large acceptance spectrometer capable of operating at the luminosity frontier. It is proposed to fully exploit the scientific potential of the continuous electron beam accelerator facility (CEBAF) 12 GeV energy upgrade at Jefferson Lab. Its conceptual design is mature, having passed multiple reviews and been validated by a successful pre-R&D phase. The envisioned scientific program consists of three avenues of research, namely the 3D momentum imaging of the structure of the nucleon, the origin of the proton mass through the gluonic gravitational form factors (GFFs), and the search of physics beyond the standard model of particle physics. These avenues are complemented by a growing supplemental list of run group experiments that address a variety of important topics.
螺线管大强度装置（Solenoidal Large Intensity Device，SoLID）是一种能够在光度前沿运行的大型接受谱仪。该装置旨在充分挖掘杰斐逊实验室 12 GeV 能量升级后的连续电子束加速器（CEBAF）的科学潜力。其概念设计已经成熟，通过了多次审查，并在预研发阶段取得了成功。设想的科学计划包括三条研究途径，即核子结构的三维动量成像、通过胶子引力形式因子（GFFs）研究质子质量的起源，以及寻找超越粒子物理标准模型的物理学。除了这些途径之外，还有不断增加的运行组实验补充清单，这些实验涉及各种重要课题。
{"title":"Electron Scattering at the Intensity Frontier with SoLID","authors":"Zein-Eddine Meziani","doi":"arxiv-2408.16037","DOIUrl":"https://doi.org/arxiv-2408.16037","url":null,"abstract":"The Solenoidal Large Intensity Device (SoLID) is a large acceptance\u0000spectrometer capable of operating at the luminosity frontier. It is proposed to\u0000fully exploit the scientific potential of the continuous electron beam\u0000accelerator facility (CEBAF) 12 GeV energy upgrade at Jefferson Lab. Its\u0000conceptual design is mature, having passed multiple reviews and been validated\u0000by a successful pre-R&D phase. The envisioned scientific program consists of\u0000three avenues of research, namely the 3D momentum imaging of the structure of\u0000the nucleon, the origin of the proton mass through the gluonic gravitational\u0000form factors (GFFs), and the search of physics beyond the standard model of\u0000particle physics. These avenues are complemented by a growing supplemental list\u0000of run group experiments that address a variety of important topics.","PeriodicalId":501374,"journal":{"name":"arXiv - PHYS - Instrumentation and Detectors","volume":"71 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142213809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The double wall-ring (DWR) rotational configuration is nowadays the instrument of choice regarding interfacial shear rheometers (ISR) in rotational configurations. Complex numerical schemes must be used in the analysis of the output data in order to appropriately deal with the coupling between interfacial and bulk fluid flows, and to separate viscous and elastic contribution or the interfacial response. We present a second generation code for analyzing the interfacial shear rheology experimental results of small amplitude oscillatory measurements made with a DWR rotational rheometer. The package presented here improves significantly the accuracy and applicability range of the previous available software packages by implementing: i) a physically motivated iterative scheme based on the probe's equation of motion, ii) an increased user selectable spatial resolution, and iii) a second order approximation for the velocity gradients at the ring surfaces. Moreover, the optimization of the computational effort allows, in many cases, for on-the-fly execution during data acquisition in real experiments.
{"title":"DWR-Drag: A new generation software for the Double Wall-Ring Interfacial Shear Rheometer's data analysis","authors":"P. Sanchez-Puga, Miguel A. Rubio","doi":"arxiv-2408.15755","DOIUrl":"https://doi.org/arxiv-2408.15755","url":null,"abstract":"The double wall-ring (DWR) rotational configuration is nowadays the\u0000instrument of choice regarding interfacial shear rheometers (ISR) in rotational\u0000configurations. Complex numerical schemes must be used in the analysis of the\u0000output data in order to appropriately deal with the coupling between\u0000interfacial and bulk fluid flows, and to separate viscous and elastic\u0000contribution or the interfacial response. We present a second generation code\u0000for analyzing the interfacial shear rheology experimental results of small\u0000amplitude oscillatory measurements made with a DWR rotational rheometer. The\u0000package presented here improves significantly the accuracy and applicability\u0000range of the previous available software packages by implementing: i) a\u0000physically motivated iterative scheme based on the probe's equation of motion,\u0000ii) an increased user selectable spatial resolution, and iii) a second order\u0000approximation for the velocity gradients at the ring surfaces. Moreover, the\u0000optimization of the computational effort allows, in many cases, for on-the-fly\u0000execution during data acquisition in real experiments.","PeriodicalId":501374,"journal":{"name":"arXiv - PHYS - Instrumentation and Detectors","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142226924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. GordiyenkoB.Verkin Institute for Low Temperature Physics and Engineering NAS of Ukraine, Yu. FomenkoB.Verkin Institute for Low Temperature Physics and Engineering NAS of Ukraine, G. ShustakovaB.Verkin Institute for Low Temperature Physics and Engineering NAS of Ukraine, G. KovalovInstitute for Problems of Cryobiology and Cryomedicine NAS of Ukraine, S. ShevchenkoB.Verkin Institute for Low Temperature Physics and Engineering NAS of Ukraine
To measure low-temperature thermal fields, we have developed a single-element cooled thermal imaging camera for a spectral range of 8{div}14 {mu}m with an internal shutter for radiometric calibration. To improve the accuracy of measuring the temperature of cold objects, we used a shutter with a combined emissivity as an internal reference source of radiation at the input of the device optical unit. With this aim a small mirror was fixed in the center on its surface covered black, thereby ensuring an efficient reflection of radiation in a wide spectral range of wavelengths. When processing the signal for each pixel of the thermal image, the differential value of the detector response to the shutter blackened and mirror areas was used as a reference. A relative measurement error of 3 percent was obtained for the studied objects with a temperature of -150 {deg}C. The device was successfully used for remote study of thermal field dynamics during freeze-thawing of biological tissues in vivo.
{"title":"Infrared thermal imaging camera to measure low temperature thermal fields","authors":"E. GordiyenkoB.Verkin Institute for Low Temperature Physics and Engineering NAS of Ukraine, Yu. FomenkoB.Verkin Institute for Low Temperature Physics and Engineering NAS of Ukraine, G. ShustakovaB.Verkin Institute for Low Temperature Physics and Engineering NAS of Ukraine, G. KovalovInstitute for Problems of Cryobiology and Cryomedicine NAS of Ukraine, S. ShevchenkoB.Verkin Institute for Low Temperature Physics and Engineering NAS of Ukraine","doi":"arxiv-2408.16165","DOIUrl":"https://doi.org/arxiv-2408.16165","url":null,"abstract":"To measure low-temperature thermal fields, we have developed a single-element\u0000cooled thermal imaging camera for a spectral range of 8{div}14 {mu}m with an\u0000internal shutter for radiometric calibration. To improve the accuracy of\u0000measuring the temperature of cold objects, we used a shutter with a combined\u0000emissivity as an internal reference source of radiation at the input of the\u0000device optical unit. With this aim a small mirror was fixed in the center on\u0000its surface covered black, thereby ensuring an efficient reflection of\u0000radiation in a wide spectral range of wavelengths. When processing the signal\u0000for each pixel of the thermal image, the differential value of the detector\u0000response to the shutter blackened and mirror areas was used as a reference. A\u0000relative measurement error of 3 percent was obtained for the studied objects\u0000with a temperature of -150 {deg}C. The device was successfully used for remote\u0000study of thermal field dynamics during freeze-thawing of biological tissues in\u0000vivo.","PeriodicalId":501374,"journal":{"name":"arXiv - PHYS - Instrumentation and Detectors","volume":"150 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142213810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
SND@LHC is a new detector for neutrino physics at LHC. Its experimental configuration makes it possible to distinguish between all three neutrino flavours, opening a unique opportunity to probe physics of heavy flavour production at the LHC in the region that is not accessible to ATLAS, CMS and LHCb. It can also explore lepton flavour universality in the neutral sector, and search for feebly interacting particles. The detector has been commissioned and installed in 2021-2022. A first set of data has since then been collected, providing the first observation of neutrinos produced at a collider. This paper discusses the detector technologies being used to study high-energy neutrinos at the LHC, and their performance in terms of physics reach. The necessary upgrades to operate at high-luminosity LHC are presented, as well as a proposed experiment to perform neutrino measurements at the newly approved Beam Dump Facility.
{"title":"A roadmap for neutrino detection at LHC, HL-LHC and SPS","authors":"Elena Graverini","doi":"arxiv-2408.15851","DOIUrl":"https://doi.org/arxiv-2408.15851","url":null,"abstract":"SND@LHC is a new detector for neutrino physics at LHC. Its experimental\u0000configuration makes it possible to distinguish between all three neutrino\u0000flavours, opening a unique opportunity to probe physics of heavy flavour\u0000production at the LHC in the region that is not accessible to ATLAS, CMS and\u0000LHCb. It can also explore lepton flavour universality in the neutral sector,\u0000and search for feebly interacting particles. The detector has been commissioned\u0000and installed in 2021-2022. A first set of data has since then been collected,\u0000providing the first observation of neutrinos produced at a collider. This paper\u0000discusses the detector technologies being used to study high-energy neutrinos\u0000at the LHC, and their performance in terms of physics reach. The necessary\u0000upgrades to operate at high-luminosity LHC are presented, as well as a proposed\u0000experiment to perform neutrino measurements at the newly approved Beam Dump\u0000Facility.","PeriodicalId":501374,"journal":{"name":"arXiv - PHYS - Instrumentation and Detectors","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142226873","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. Akchurin, J. Cash, J. Damgov, X. Delashaw, K. Lamichhane, M. Harris, M. Kelley, S. Kunori, H. Mergate-Cacace, T. Peltola, O. Schneider, J. Sewell
The fluctuations in energy loss to processes that do not generate measurable signals, such as binding energy losses, set the limit on achievable hadronic energy resolution in traditional energy reconstruction techniques. The correlation between the number of hadronic interaction vertices in a shower and invisible energy is found to be strong and is used to estimate invisible energy fraction in highly granular calorimeters in short time intervals (<10 ns). We simulated images of hadronic showers using GEANT4 and deployed a neural network to analyze the images for energy regression. The neural network-based approach results in significant improvement in energy resolution, from 13 % to 4 % in the case of a Cherenkov calorimeter for 100 GeV pion showers. We discuss the significance of the phenomena responsible for this improvement and the plans for experimental verification of these results and further development.
{"title":"Vertex Imaging Hadron Calorimetry Using AI/ML Tools","authors":"N. Akchurin, J. Cash, J. Damgov, X. Delashaw, K. Lamichhane, M. Harris, M. Kelley, S. Kunori, H. Mergate-Cacace, T. Peltola, O. Schneider, J. Sewell","doi":"arxiv-2408.15385","DOIUrl":"https://doi.org/arxiv-2408.15385","url":null,"abstract":"The fluctuations in energy loss to processes that do not generate measurable\u0000signals, such as binding energy losses, set the limit on achievable hadronic\u0000energy resolution in traditional energy reconstruction techniques. The\u0000correlation between the number of hadronic interaction vertices in a shower and\u0000invisible energy is found to be strong and is used to estimate invisible energy\u0000fraction in highly granular calorimeters in short time intervals (<10 ns). We\u0000simulated images of hadronic showers using GEANT4 and deployed a neural network\u0000to analyze the images for energy regression. The neural network-based approach\u0000results in significant improvement in energy resolution, from 13 % to 4 % in\u0000the case of a Cherenkov calorimeter for 100 GeV pion showers. We discuss the\u0000significance of the phenomena responsible for this improvement and the plans\u0000for experimental verification of these results and further development.","PeriodicalId":501374,"journal":{"name":"arXiv - PHYS - Instrumentation and Detectors","volume":"95 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142213813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. Akchurin, J. Cash, J. Damgov, X. Delashaw, K. Lamichhane, M. Harris, M. Kelley, S. Kunori, H. Mergate-Cacace, T. Peltola, O. Schneider, J. Sewell
The original dual-readout calorimeter prototype (DREAM), constructed two decades ago, has proven instrumental in advancing our understanding of calorimetry. It has facilitated a multitude of breakthroughs by leveraging signals from complementary media (Cherenkov and scintillation) to capture fluctuations in electromagnetic energy fraction within hadronic showers. Over the years, extensive studies have shed light on the performance characteristics of this module, rendering it exceptionally well-understood. Drawing on this wealth of experience, we have embarked on enhancing the detectors' capabilities further by integrating fast silicon photomultipliers (SiPMs) with finer transverse segmentation, $sim$1 cm$^2$, as well as longitudinal segmentation by timing measuring better than 10 cm. This configuration will allow us to image hadronic showers with high granularity (HG-DREAM). We argue that the spatial information provided by such a granular detector in a short time window ($approx$5 ns) leads to substantial enhancement in energy resolution when advanced neural networks are employed in energy reconstruction. We briefly present the current status of work, new concepts that have been introduced to the detector, and expectations from simulations.
{"title":"High-granularity Dual-readout Calorimeter: Evolution of a Classic Prototype","authors":"N. Akchurin, J. Cash, J. Damgov, X. Delashaw, K. Lamichhane, M. Harris, M. Kelley, S. Kunori, H. Mergate-Cacace, T. Peltola, O. Schneider, J. Sewell","doi":"arxiv-2408.15430","DOIUrl":"https://doi.org/arxiv-2408.15430","url":null,"abstract":"The original dual-readout calorimeter prototype (DREAM), constructed two\u0000decades ago, has proven instrumental in advancing our understanding of\u0000calorimetry. It has facilitated a multitude of breakthroughs by leveraging\u0000signals from complementary media (Cherenkov and scintillation) to capture\u0000fluctuations in electromagnetic energy fraction within hadronic showers. Over\u0000the years, extensive studies have shed light on the performance characteristics\u0000of this module, rendering it exceptionally well-understood. Drawing on this\u0000wealth of experience, we have embarked on enhancing the detectors' capabilities\u0000further by integrating fast silicon photomultipliers (SiPMs) with finer\u0000transverse segmentation, $sim$1 cm$^2$, as well as longitudinal segmentation\u0000by timing measuring better than 10 cm. This configuration will allow us to\u0000image hadronic showers with high granularity (HG-DREAM). We argue that the\u0000spatial information provided by such a granular detector in a short time window\u0000($approx$5 ns) leads to substantial enhancement in energy resolution when\u0000advanced neural networks are employed in energy reconstruction. We briefly\u0000present the current status of work, new concepts that have been introduced to\u0000the detector, and expectations from simulations.","PeriodicalId":501374,"journal":{"name":"arXiv - PHYS - Instrumentation and Detectors","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142226872","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In-Vessel Retention (IVR) strategy for nuclear reactors in case of a Severe Accident (SA) intends to stabilize and retain the corium in the vessel by using the vessel wall as a heat exchanger with an external water loop. This strategy relies on simple actions to be passively taken as soon as SA signal is raised: vessel depressurization and reactor pit flooding. Then, the strategy is successful if the vessel keeps it integrity, which means that the heat flux coming from the corium pool does not exceed the cooling capacity of the External Reactor Vessel Cooling (ERVC) at each location along the vessel wall (no vessel melt-through) and the ablated vessel wall is mechanically resistant. The main uncertainties in this IVR safety evaluation are associated to the thermal load applied from the corium pool to the vessel wall and the resulting minimum vessel thickness after ablation. Indeed, the heat fluxes distribution along the vessel wall is directly dependent on the corium stratification which occurs as aresult of thermochemical interactions in the pool: when liquid steel is mixed with UO2 and partially oxidized Zr coming from the degradation of the fuel and claddings, there is a phase separation between oxide and metal phases due to a gap of miscibility. The primordial impact of the corium behaviour in the lower plenum of the reactor vessel on the IVR safety evaluation was clearly highlighted in the Phenomena Identification Ranking Table (PIRT) on IVR performed in the frame of the European IVMR (In-Vessel Melt Retention) project (Fichot et al., 2019). As a result, the focus is made in this paper on the critical points which impact the value of the minimum vessel thickness orequivalently the maximum heat flux reached at the outer surface of the vessel wall. Efficiency of the ERVC and mechanical resistance of the vessel wall are consequently not discussed here.The main objective is to identify the generic critical situations leading to an excessive heat flux to the vessel wall and the investigation of possible means to avoid them. In this perspective, the calculations of IVR strategy done by the project partners for different reactor designs and accident scenarios were used as a database to identify and understand the occurrence of critical configurations with excessive heat flux to the vessel wall. The results of 25 sequences are used, which correspond to 9 different reactor designs: a generic PWR 900MWe, a PWR 1100MWe with heavy reflector, a generic PWR 1300MWe, a generic Konvoi 1300MWe, a generic German BWR69, aNordic BWR, a BWR-5 Mark II, a VVER1000 and a VVER440/v213. In addition, different SA integral codes (ASTEC, ATHLET-CD, MAAP -combined with MAAP_EDF and PROCOR codes for simulation of lower plenum behavior-, MELCOR and RELAP/SCDAPSIM codes) are used.
{"title":"Analysis of critical points of the In-Vessel Retention safety evaluation","authors":"Laure CaréniniIRSN/PSN-RES/SAM/LEPC, Florian FichotIRSN/PSN-RES/SAM/LEPC","doi":"arxiv-2408.15290","DOIUrl":"https://doi.org/arxiv-2408.15290","url":null,"abstract":"In-Vessel Retention (IVR) strategy for nuclear reactors in case of a Severe\u0000Accident (SA) intends to stabilize and retain the corium in the vessel by using\u0000the vessel wall as a heat exchanger with an external water loop. This strategy\u0000relies on simple actions to be passively taken as soon as SA signal is raised:\u0000vessel depressurization and reactor pit flooding. Then, the strategy is\u0000successful if the vessel keeps it integrity, which means that the heat flux\u0000coming from the corium pool does not exceed the cooling capacity of the\u0000External Reactor Vessel Cooling (ERVC) at each location along the vessel wall\u0000(no vessel melt-through) and the ablated vessel wall is mechanically resistant.\u0000The main uncertainties in this IVR safety evaluation are associated to the\u0000thermal load applied from the corium pool to the vessel wall and the resulting\u0000minimum vessel thickness after ablation. Indeed, the heat fluxes distribution\u0000along the vessel wall is directly dependent on the corium stratification which\u0000occurs as aresult of thermochemical interactions in the pool: when liquid steel\u0000is mixed with UO2 and partially oxidized Zr coming from the degradation of the\u0000fuel and claddings, there is a phase separation between oxide and metal phases\u0000due to a gap of miscibility. The primordial impact of the corium behaviour in\u0000the lower plenum of the reactor vessel on the IVR safety evaluation was clearly\u0000highlighted in the Phenomena Identification Ranking Table (PIRT) on IVR\u0000performed in the frame of the European IVMR (In-Vessel Melt Retention) project\u0000(Fichot et al., 2019). As a result, the focus is made in this paper on the\u0000critical points which impact the value of the minimum vessel thickness\u0000orequivalently the maximum heat flux reached at the outer surface of the vessel\u0000wall. Efficiency of the ERVC and mechanical resistance of the vessel wall are\u0000consequently not discussed here.The main objective is to identify the generic\u0000critical situations leading to an excessive heat flux to the vessel wall and\u0000the investigation of possible means to avoid them. In this perspective, the\u0000calculations of IVR strategy done by the project partners for different reactor\u0000designs and accident scenarios were used as a database to identify and\u0000understand the occurrence of critical configurations with excessive heat flux\u0000to the vessel wall. The results of 25 sequences are used, which correspond to 9\u0000different reactor designs: a generic PWR 900MWe, a PWR 1100MWe with heavy\u0000reflector, a generic PWR 1300MWe, a generic Konvoi 1300MWe, a generic German\u0000BWR69, aNordic BWR, a BWR-5 Mark II, a VVER1000 and a VVER440/v213. In\u0000addition, different SA integral codes (ASTEC, ATHLET-CD, MAAP -combined with\u0000MAAP_EDF and PROCOR codes for simulation of lower plenum behavior-, MELCOR and\u0000RELAP/SCDAPSIM codes) are used.","PeriodicalId":501374,"journal":{"name":"arXiv - PHYS - Instrumentation and Detectors","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142213838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. H. Yu, N. Carlin, J. Y. Cho, J. J. Choi, S. Choi, A. C. Ezeribe, L. E. França, C. Ha, I. S. Hahn, S. J. Hollick, E. J. Jeon, H. W. Joo, W. G. Kang, M. Kauer, B. H. Kim, H. J. Kim, J. Kim, K. W. Kim, S. H. Kim, S. K. Kim, W. K. Kim, Y. D. Kim, Y. H. Kim, Y. J. Ko, D. H. Lee, E. K. Lee, H. Lee, H. S. Lee, H. Y. Lee, I. S. Lee, J. Lee, J. Y. Lee, M. H. Lee, S. H. Lee, S. M. Lee, Y. J. Lee, D. S. Leonard, N. T. Luan, V. H. A. Machado, B. B. Manzato, R. H. Maruyama, R. J. Neal, S. L. Olsen, B. J. Park, H. K. Park, H. S. Park, J. C. Park, K. S. Park, S. D. Park, R. L. C. Pitta, H. Prihtiadi, S. J. Ra, C. Rott, K. A. Shin, D. F. F. S. Cavalcante, M. K. Son, N. J. C. Spooner, L. T. Truc, L. Yang
COSINE-100 is a direct dark matter search experiment, with the primary goal of testing the annual modulation signal observed by DAMA/LIBRA, using the same target material, NaI(Tl). In previous analyses, we achieved the same 1 keV energy threshold used in the DAMA/LIBRA's analysis that reported an annual modulation signal with 11.6$sigma$ significance. In this article, we report an improved analysis that lowered the threshold to 0.7 keV, thanks to the application of Multi-Layer Perception network and a new likelihood parameter with waveforms in the frequency domain. The lower threshold would enable a better comparison of COSINE-100 with new DAMA results with a 0.75 keV threshold and account for differences in quenching factors. Furthermore the lower threshold can enhance COSINE-100's sensitivity to sub-GeV dark matter searches.
{"title":"Lowering threshold of NaI(Tl) scintillator to 0.7 keV in the COSINE-100 experiment","authors":"G. H. Yu, N. Carlin, J. Y. Cho, J. J. Choi, S. Choi, A. C. Ezeribe, L. E. França, C. Ha, I. S. Hahn, S. J. Hollick, E. J. Jeon, H. W. Joo, W. G. Kang, M. Kauer, B. H. Kim, H. J. Kim, J. Kim, K. W. Kim, S. H. Kim, S. K. Kim, W. K. Kim, Y. D. Kim, Y. H. Kim, Y. J. Ko, D. H. Lee, E. K. Lee, H. Lee, H. S. Lee, H. Y. Lee, I. S. Lee, J. Lee, J. Y. Lee, M. H. Lee, S. H. Lee, S. M. Lee, Y. J. Lee, D. S. Leonard, N. T. Luan, V. H. A. Machado, B. B. Manzato, R. H. Maruyama, R. J. Neal, S. L. Olsen, B. J. Park, H. K. Park, H. S. Park, J. C. Park, K. S. Park, S. D. Park, R. L. C. Pitta, H. Prihtiadi, S. J. Ra, C. Rott, K. A. Shin, D. F. F. S. Cavalcante, M. K. Son, N. J. C. Spooner, L. T. Truc, L. Yang","doi":"arxiv-2408.14688","DOIUrl":"https://doi.org/arxiv-2408.14688","url":null,"abstract":"COSINE-100 is a direct dark matter search experiment, with the primary goal\u0000of testing the annual modulation signal observed by DAMA/LIBRA, using the same\u0000target material, NaI(Tl). In previous analyses, we achieved the same 1 keV\u0000energy threshold used in the DAMA/LIBRA's analysis that reported an annual\u0000modulation signal with 11.6$sigma$ significance. In this article, we report an\u0000improved analysis that lowered the threshold to 0.7 keV, thanks to the\u0000application of Multi-Layer Perception network and a new likelihood parameter\u0000with waveforms in the frequency domain. The lower threshold would enable a\u0000better comparison of COSINE-100 with new DAMA results with a 0.75 keV threshold\u0000and account for differences in quenching factors. Furthermore the lower\u0000threshold can enhance COSINE-100's sensitivity to sub-GeV dark matter searches.","PeriodicalId":501374,"journal":{"name":"arXiv - PHYS - Instrumentation and Detectors","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142213814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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