Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms最新文献

{"title":"A method to detect the VUV photons from cooled 229Th:CaF2 crystals","authors":"Ming Guan ,&nbsp;Michael Bartokos ,&nbsp;Kjeld Beeks ,&nbsp;Yuta Fukunaga ,&nbsp;Takahiro Hiraki ,&nbsp;Takahiko Masuda ,&nbsp;Yuki Miyamoto ,&nbsp;Ryoichiro Ogake ,&nbsp;Koichi Okai ,&nbsp;Noboru Sasao ,&nbsp;Fabian Schaden ,&nbsp;Thorsten Schumm ,&nbsp;Kotaro Shimizu ,&nbsp;Sayuri Takatori ,&nbsp;Akihiro Yoshimi ,&nbsp;Koji Yoshimura","doi":"10.1016/j.nimb.2025.165647","DOIUrl":"10.1016/j.nimb.2025.165647","url":null,"abstract":"<div><div>Thorium-229, with its exceptionally low-energy nuclear excited state, is the only candidate for developing a nuclear clock. ²²⁹Th-doped CaF<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> crystals, benefiting from calcium fluoride’s wide band gap, show great promise as solid-state nuclear clock materials. These crystals are excited by vacuum ultraviolet (VUV) lasers, which over time cause radiation damage. Cooling the crystals can mitigate this damage but introduces a challenge: photoabsorption. This occurs when residual gas molecules condense on the crystal surface, absorbing VUV photons and deteriorating detection efficiency. To solve this, we developed a cooling technique using a copper shield to surround the crystal, acting as a cold trap. This prevents ice-layer formation, even at temperatures below <span><math><mrow><mo>−</mo><mn>100</mn><mspace></mspace><mo>°</mo><mi>C</mi></mrow></math></span>, preserving high VUV photon detection efficiency. Our study detailed the experimental cooling setup and demonstrated the effectiveness of the copper shield in maintaining crystal performance, a critical improvement for future solid-state nuclear clocks operating at cryogenic temperatures.</div></div>","PeriodicalId":19380,"journal":{"name":"Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms","volume":"562 ","pages":"Article 165647"},"PeriodicalIF":1.4,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143428020","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Scattering effects on X-ray imaging of bubbly flow in metal pipes","authors":"Jianxian Song ,&nbsp;Hailiang Yang ,&nbsp;Pengfei Zhang ,&nbsp;Jinhua Wang ,&nbsp;Zhiguo Wang ,&nbsp;Wuguang Chen ,&nbsp;Junlian Yin","doi":"10.1016/j.nimb.2025.165646","DOIUrl":"10.1016/j.nimb.2025.165646","url":null,"abstract":"<div><div>Improving X-ray imaging performance is crucial for measuring two-phase flow details inside opaque metal pipes. This research explores the capabilities of Monte Carlo (MC) and Beer-Lambert (BL) simulations for optimizing X-ray imaging system settings. The accuracy of the simulation methodology is confirmed by comparing simulation images with experimental results and previous research. The comparison between MC results and BL results indicated that scattering increases image non-uniformity. The comparison also illustrates the accuracy of BL simulation. Finally, the impact of acceleration voltage is analyzed using validated BL simulation. The result indicated that a higher acceleration voltage increases bubble signal-to-noise ratio (SNR), despite the lower image contrast produced by high-energy photons. Thus, a higher acceleration voltage is recommended, rather than the commonly used 150 kV.</div></div>","PeriodicalId":19380,"journal":{"name":"Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms","volume":"562 ","pages":"Article 165646"},"PeriodicalIF":1.4,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143428107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Background subtraction in inelastic scattering measurements using machine learning","authors":"R. Ghimire ,&nbsp;A. Ratkiewicz ,&nbsp;S.D. Pain ,&nbsp;K.A. Chipps ,&nbsp;J.A. Cizewski ,&nbsp;K.L. Jones ,&nbsp;P. Bedrossian ,&nbsp;S.R. Carmichael ,&nbsp;H. Garland ,&nbsp;Claus Müller-Gatermann ,&nbsp;R.O. Hughes ,&nbsp;H. Jayatissa ,&nbsp;K. Kolos ,&nbsp;J.M. Kovoor ,&nbsp;A. Kyle ,&nbsp;W. Reviol ,&nbsp;A. Richard ,&nbsp;N.D. Scielzo ,&nbsp;M. Siciliano ,&nbsp;H. Sims ,&nbsp;S. Zhu","doi":"10.1016/j.nimb.2025.165649","DOIUrl":"10.1016/j.nimb.2025.165649","url":null,"abstract":"<div><div>Identifying, isolating, and subtracting background from the signal of interest is vital for nuclear physics experiments. These backgrounds introduce unwanted uncertainties that must be accounted for properly to extract accurate results from the signals. In nuclear reaction measurements, the typical contaminants are carbon and oxygen, contributing to background signals, and complicating the measurement of the light ejectiles. For instance, in the inelastic scattering measurement of a 20.9-MeV proton beam on ⁹⁶Mo, the ⁹⁶Mo target was contaminated with carbon and oxygen. We used random forest, a machine learning algorithm commonly used for classification and regression tasks, to separate the inelastic scattering on the carbon and oxygen contaminants from the data of interest resulting from ⁹⁶Mo(<span><math><mrow><mi>p</mi><mo>,</mo><msup><mrow><mi>p</mi></mrow><mrow><mo>′</mo></mrow></msup></mrow></math></span>).</div></div>","PeriodicalId":19380,"journal":{"name":"Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms","volume":"561 ","pages":"Article 165649"},"PeriodicalIF":1.4,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143419409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Damage and degradation region of GaN HEMTs induced by different radiation effects","authors":"Qi-Yao Wang,&nbsp;Ying Wang,&nbsp;Jun Liu,&nbsp;Wen-jun Li,&nbsp;Cheng-hao Yu,&nbsp;Hao-min Guo","doi":"10.1016/j.nimb.2025.165635","DOIUrl":"10.1016/j.nimb.2025.165635","url":null,"abstract":"<div><div>With the increasing demand for higher power density and operating frequency in modern power systems, traditional semiconductor power devices are approaching their material limits. Consequently, there is a growing need for a new generation of semiconductor devices. Gallium nitride (GaN) is widely regarded as the primary candidate material for the next generation of power devices, with AlGaN/GaN HEMTs developed using it as the core material attracting increasing attention. This work aims to summarize the impact of different radiation effects on GaN HEMTs in various scenarios, including radiation damage mechanisms, vulnerable areas, and electrical degradation. Furthermore, this work highlights the potential development trajectory for enhancement mode devices through previously proposed radiation hardening schemes.</div></div>","PeriodicalId":19380,"journal":{"name":"Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms","volume":"561 ","pages":"Article 165635"},"PeriodicalIF":1.4,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative elemental analysis of collagen vascular-associated lung diseases by in-air micro- PIXE, a pilot study","authors":"Yasuhiko Koga ,&nbsp;Takahiro Satoh ,&nbsp;Ryohei Yamagata ,&nbsp;Yasuyuki Ishii ,&nbsp;Wataru Kada ,&nbsp;Takeshi Hisada ,&nbsp;Kunio Dobashi","doi":"10.1016/j.nimb.2025.165634","DOIUrl":"10.1016/j.nimb.2025.165634","url":null,"abstract":"<div><h3>Background</h3><div>Collagen vascular disease (CVD) is a systemic disease in which connective tissue abnormalities of systemic organs such as the skin, kidneys, lungs, and lymph nodes are caused by abnormal functions of the immune system. The cause of CVD has not been clarified yet, but it has been suggested that exposure to heavy metals and silica may be the cause of vasculitis and systemic sclerosis.</div></div><div><h3>Purpose</h3><div>In this study, we focused on the elemental analysis of lung tissues complicated with collagen vascular disease-associated interstitial lung disease (CVD-ILD) and investigated the relationship between inhaled elements and CVD-ILD.</div></div><div><h3>Methods</h3><div>We examined the inhaled elements in the lungs using in-air micro-particle-induced X-ray emission analysis (in-air micro-PIXE). Elemental analysis of lung tissue specimens was performed by using 5 cases of systemic sclerosis and 3 cases of aminoacyl-tRNA synthetase (ARS) antibody-positive dermatomyositis surgically resected by thoracoscopic lung biopsy. Control lung samples were obtained from early-stage lung cancer patients. The relative amounts of each elements divided with sulfur in the lung was statistically analyzed.</div></div><div><h3>Results</h3><div>There was a significant difference between CVD-ILD and the control lung in terms of inhaled silica/silicates. Furthermore, relative silica deposition was higher in scleroderma lungs compared to control lungs, but not in lungs from ARS-positive cases.</div></div><div><h3>Conclusion</h3><div>These results indicated that silica deposition in lung tissue may be involved in the pathogenesis of CVD-ILD, especially systemic sclerosis.</div></div>","PeriodicalId":19380,"journal":{"name":"Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms","volume":"561 ","pages":"Article 165634"},"PeriodicalIF":1.4,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143378438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multiple threshold displacement energy in Non-Ionizing Energy Loss calculations for compound semiconductors","authors":"C. Inguimbert","doi":"10.1016/j.nimb.2025.165622","DOIUrl":"10.1016/j.nimb.2025.165622","url":null,"abstract":"<div><div>The traditional approach to evaluate the Displacement Damage Dose (DDD) effects in irradiated materials hinges on the concept of Non-Ionizing Energy Loss (NIEL). Historically, this method uses a single atomic displacement threshold energy (E_d) as a benchmark. But a single E_d just doesn’t cut it when it comes to accurately capturing the damage caused by electrons. To tackle this shortcoming, a more refined technique has been devised—one that introduces a spectrum of threshold energies into the NIEL calculations. Initially crafted for monatomic materials, this method has now been tailored for compound materials. Here, we propose updated NIEL values for certain III-V semiconductors and compare them with experimental damage factors, particularly emphasizing the effects of electron interactions.</div></div>","PeriodicalId":19380,"journal":{"name":"Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms","volume":"561 ","pages":"Article 165622"},"PeriodicalIF":1.4,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143267690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Surface modification of Al-W laser-alloyed layer by high current pulsed electron beam irradiation","authors":"Hongxing Chen ,&nbsp;Conglin Zhang ,&nbsp;Nana Tian ,&nbsp;Jintong Guan ,&nbsp;Shuang Tian ,&nbsp;Qingfeng Guan","doi":"10.1016/j.nimb.2025.165629","DOIUrl":"10.1016/j.nimb.2025.165629","url":null,"abstract":"<div><div>In this paper, high-current pulsed electron beam (HCPEB) technology was used to modify an Al-W alloying layer prepared by laser surface alloying (LSA). The microstructural changes were characterized by scanning electron microscope (SEM), X-ray diffractometer (XRD) and transmission electron microscope (TEM). The microhardness and friction properties were tested to explore the mechanism behind the performance enhancement. After HCPEB irradiation, the Al-W particles were dissolved and diffused to form a homogeneous re-melt layer on the topmost surface of Al-W laser-alloyed layer, approximately 20 μm thick. The phase compositions of the alloying layer consisted of α-Al, Al₁₂W, Al₅W, and Al₄W phases. Additionally, HCPEB irradiation induced the formation of ultrafine crystals and a variety of crystal defect structures in the topmost Al-W laser-alloyed layer. The hardness of the Al-W laser-alloyed layer was significantly enhanced after HCPEB irradiation. Furthermore, the friction and wear properties of the alloying layer were significantly improved, which was mainly related to the formation of an abundant dislocation structure, Al-W particles and grain refinement.</div></div>","PeriodicalId":19380,"journal":{"name":"Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms","volume":"561 ","pages":"Article 165629"},"PeriodicalIF":1.4,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143267689","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A study of afterglow signatures in NaI and CsI scintillator modules for the background and transient observer instrument on COSI","authors":"Hannah Gulick ,&nbsp;Hiroki Yoneda ,&nbsp;Tadayuki Takahashi ,&nbsp;Claire Chen ,&nbsp;Kazuhiro Nakazawa ,&nbsp;Shunsaku Nagasawa ,&nbsp;Mii Ando ,&nbsp;Keigo Okuma ,&nbsp;Alyson Joens ,&nbsp;Samer Al Nussirat ,&nbsp;Yasuyuki Shimizu ,&nbsp;Kaito Fujisawa ,&nbsp;Takayoshi Kohmura ,&nbsp;Kouichi Hagino ,&nbsp;Hisashi Kitamura ,&nbsp;Andreas Zoglauer ,&nbsp;Juan Carlos Martinez Oliveros ,&nbsp;John A. Tomsick","doi":"10.1016/j.nimb.2025.165631","DOIUrl":"10.1016/j.nimb.2025.165631","url":null,"abstract":"<div><div>We present measurements of the afterglow signatures in NaI(Tl) and CsI(Tl) detector modules as part of the Background and Transient Observer (BTO) mission detector trade-study. BTO is a NASA Student Collaboration Project flying on the Compton Spectrometer and Imager (COSI) Small Explorer mission in 2027. The detectors utilized in this study are cylindrical in shape with a height and diameter of 5.1 cm and were read out by silicon photomultipliers (SiPMs). We conducted a radiation campaign at the HIMAC accelerator in Japan where the scintillators were irradiated with a 230 MeV/u helium beam (He beam) and 350 MeV/u carbon beam (C beam). We find that both the CsI and NaI scintillators exhibit afterglow signatures when irradiated with the C and He beams. The CsI crystal exhibits a stronger afterglow intensity with afterglow pulses occurring for an average 2.40 ms for C and 0.9 ms for He after the initial particle pulse. The duration of afterglow pulses in CsI is 8.6<span><math><mo>×</mo></math></span> and 5.6<span><math><mo>×</mo></math></span> the afterglow signal duration in NaI for C and He (0.28 ms and 0.16 ms, respectively). Although CsI has advantages such as a higher light yield and radiation hardness, the stronger afterglows in the CsI detector increase the complexity of the electronics and lead to a <span><math><mrow><mo>∼</mo><mn>7</mn><mo>×</mo></mrow></math></span> larger dead time per afterglow event or a <span><math><mrow><mo>∼</mo><mn>3</mn><mo>×</mo></mrow></math></span> higher energy threshold value. We use the measured dead times to predict the amount of observing time lost to afterglow-inducing events for an instrument like BTO in low Earth orbit. We simulate the background rates in a BTO-like orbit and find a total value of 114 counts/s for the full two-detector system. Based on the particle energies in the HIMAC experiment, we then determine that an event with sufficient energy to produce an afterglow signal occurs once every <span><math><mo>∼</mo></math></span>70 s and <span><math><mo>∼</mo></math></span>1.4 s in NaI and CsI detectors, respectively. Thus, we conclude that NaI is the better choice for the BTO mission.</div></div>","PeriodicalId":19380,"journal":{"name":"Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms","volume":"561 ","pages":"Article 165631"},"PeriodicalIF":1.4,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143182968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ab initio modeling of vacancies and interstitials elements at Σ3(11-1) symmetric tilt grain boundaries in α-Fe","authors":"R.M. Meftakhutdinov","doi":"10.1016/j.nimb.2025.165627","DOIUrl":"10.1016/j.nimb.2025.165627","url":null,"abstract":"<div><div>The article presents data obtained by the ab initio method of calculating point defects (vacancies, native and foreign interstitial atoms (C, N, Cr)) near the symmetric <span><math><mi>Σ</mi></math></span>3(11-1) boundary in α-Fe. It has been elicited that the formation energies of interstitial Cr and Fe are less, and C and N are greater than in bulk Fe. The introduction of Fe, Cr and N at the boundary leads to a weakening of the bond between grains, and C, on the contrary, to strengthening. The interaction of interstitial atoms with vacancies is characterized.</div></div>","PeriodicalId":19380,"journal":{"name":"Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms","volume":"561 ","pages":"Article 165627"},"PeriodicalIF":1.4,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143182963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radiation hardness study of liquid scintillator under 80 MeV proton beam irradiations","authors":"Wenbao Qu ,&nbsp;Haisheng Song ,&nbsp;Boxiang Yu ,&nbsp;Zhixin Tan ,&nbsp;Yuhang Guo ,&nbsp;You Lv ,&nbsp;Hantao Jing ,&nbsp;Ruirui Fan ,&nbsp;Shuaishuai Ren ,&nbsp;Tao Hu","doi":"10.1016/j.nimb.2025.165628","DOIUrl":"10.1016/j.nimb.2025.165628","url":null,"abstract":"<div><div>For monitoring the 1.6 GeV high-energy proton beam, used in the CSNS Phase II upgrade project, a liquid scintillator (LS) detector has become a viable option due to its excellent radiation hardness and the possibility of exchanging the LS remotely. This work investigates the effects of radiation damage on LS samples based on linear alkylbenzene (LAB) induced by 80 MeV protons. The study includes absorption, fluorescence spectroscopy, and light output measurement of the LS before and after proton irradiation, with a focus on determining the radiation resistance threshold of the LS. The results show that the performance of the LS is not affected at absorbed doses up to 2.44 <span><math><mo>×</mo></math></span> <span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>3</mn></mrow></msup></mrow></math></span> Gy. This demonstrates its ability to absorb 8.82 <span><math><mo>×</mo></math></span> <span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>12</mn></mrow></msup></mrow></math></span> p/cm² 1.6 GeV protons and remain stable. This suggests that a detector based on LS could potentially be used for monitoring the high-energy proton beam of 1.6 GeV in the CSNS Phase II Upgrade Project.</div></div>","PeriodicalId":19380,"journal":{"name":"Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms","volume":"561 ","pages":"Article 165628"},"PeriodicalIF":1.4,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143182966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}