Excitation functions of several evaporation residues populated via complete and/or incomplete fusion in $^{12}$C+$^{193}$Ir system have been measured at energies $approx$ 64-84 MeV, and analyzed in the framework of theoretical model code PACE4. It has been found that the $xn$ channels are predominantly populated via complete fusion; however, some of the $pxn$ channels decay via their precursor. A significant enhancement has been observed in the case of $alpha$-emitting channels over PACE4 calculations, indicating the onset of a reaction mechanism not included in this code, e.g., incomplete fusion. For better insights into the onset and influence of incomplete fusion, the percentage fraction of incomplete fusion has been deduced and analyzed in terms of different entrance-channel parameters. The findings of the present study underline the importance of projectile energy, entrance-channel mass-asymmetry, and the Coulomb factor of interacting partners. The impact of projectile break-up on complete fusion has also been discussed in the framework of the Universal Fusion Function, where suppression of $approx$ 12$%$ has been observed in the fusion function. The finding of the present work reinstates that the fusion suppression is affected by the projectile $alpha$-break-up threshold.
{"title":"Influence of incomplete fusion in $^{12}$C+$^{193}$Ir at $E_{lab}$ = 64-84 MeV","authors":"Amanjot, Priyanka, Rupinderjeet Kaur, Subham Kumar, Malika Kaushik, Manoj Kumar Sharma, Yashraj Jangid, Rakesh Kumar, Pushpendra P. Singh","doi":"arxiv-2409.01632","DOIUrl":"https://doi.org/arxiv-2409.01632","url":null,"abstract":"Excitation functions of several evaporation residues populated via complete\u0000and/or incomplete fusion in $^{12}$C+$^{193}$Ir system have been measured at\u0000energies $approx$ 64-84 MeV, and analyzed in the framework of theoretical\u0000model code PACE4. It has been found that the $xn$ channels are predominantly\u0000populated via complete fusion; however, some of the $pxn$ channels decay via\u0000their precursor. A significant enhancement has been observed in the case of\u0000$alpha$-emitting channels over PACE4 calculations, indicating the onset of a\u0000reaction mechanism not included in this code, e.g., incomplete fusion. For\u0000better insights into the onset and influence of incomplete fusion, the\u0000percentage fraction of incomplete fusion has been deduced and analyzed in terms\u0000of different entrance-channel parameters. The findings of the present study\u0000underline the importance of projectile energy, entrance-channel mass-asymmetry,\u0000and the Coulomb factor of interacting partners. The impact of projectile\u0000break-up on complete fusion has also been discussed in the framework of the\u0000Universal Fusion Function, where suppression of $approx$ 12$%$ has been\u0000observed in the fusion function. The finding of the present work reinstates\u0000that the fusion suppression is affected by the projectile $alpha$-break-up\u0000threshold.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":"93 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212802","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}
Shahina, R. J. deBoer, J. Gorres, R. Fang, M. Febbraro, R. Kelmar, M. Matney, K. Manukyan, J. T. Nattress, E. Robles, T. J. Ruland, T. T. King, A. Sanchez, R. S. Sidhu, E. Stech, M. Wiescher
The interplay between the $^{22}$Ne$(alpha,gamma)^{26}$Mg and the competing $^{22}$Ne$(alpha,n)^{25}$Mg reactions determines the efficiency of the latter as a neutron source at the temperatures of stellar helium burning. In both cases, the rates are dominated by the $alpha$-cluster resonance at 830 keV. This resonance plays a particularly important role in determining the strength of the neutron flux for both the weak and main $s$-process as well as the $n$-process. Recent experimental studies based on transfer reactions suggest that the neutron and $gamma$-ray strengths for this resonance are approximately equal. In this study, the $^{22}$Ne$(alpha,n)^{25}$Mg resonance strength has been remeasured and found to be similar to the previous direct studies. This reinforces an 830 keV resonance strength that is approximately a factor of three larger for the $^{22}$Ne$(alpha,n)^{25}$Mg reaction than for the $^{22}$Ne$(alpha,gamma)^{26}$Mg reaction.
{"title":"Strength measurement of the $E_α^{lab}$ = 830 keV resonance in $^{22}rm{Ne}(α,n)^{25}rm{Mg}$ reaction using a stilbene detector","authors":"Shahina, R. J. deBoer, J. Gorres, R. Fang, M. Febbraro, R. Kelmar, M. Matney, K. Manukyan, J. T. Nattress, E. Robles, T. J. Ruland, T. T. King, A. Sanchez, R. S. Sidhu, E. Stech, M. Wiescher","doi":"arxiv-2409.01393","DOIUrl":"https://doi.org/arxiv-2409.01393","url":null,"abstract":"The interplay between the $^{22}$Ne$(alpha,gamma)^{26}$Mg and the competing\u0000$^{22}$Ne$(alpha,n)^{25}$Mg reactions determines the efficiency of the latter\u0000as a neutron source at the temperatures of stellar helium burning. In both\u0000cases, the rates are dominated by the $alpha$-cluster resonance at 830 keV.\u0000This resonance plays a particularly important role in determining the strength\u0000of the neutron flux for both the weak and main $s$-process as well as the\u0000$n$-process. Recent experimental studies based on transfer reactions suggest\u0000that the neutron and $gamma$-ray strengths for this resonance are\u0000approximately equal. In this study, the $^{22}$Ne$(alpha,n)^{25}$Mg resonance\u0000strength has been remeasured and found to be similar to the previous direct\u0000studies. This reinforces an 830 keV resonance strength that is approximately a\u0000factor of three larger for the $^{22}$Ne$(alpha,n)^{25}$Mg reaction than for\u0000the $^{22}$Ne$(alpha,gamma)^{26}$Mg reaction.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212803","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 Electron-Ion Collider in China (EicC) is pivotal in enhancing our knowledge of the internal structure of nucleons and nuclei, particularly through the study of transverse momentum-dependent parton distributions (TMDs). Among the leading-twist TMDs, the Sivers function is of particular interest, as it provides crucial insights into the spin and momentum structure of hadrons and plays a significant role in describing transverse single spin asymmetries (SSAs) in high-energy scatterings. In this study, we focus on the theoretical framework and phenomenological implications of the Sivers function in the context of small-x physics, where it is intricately connected to the spin-dependent QCD odderon, demonstrating that the SSA can be expressed in terms of transverse momentum-dependent factorization within the Color Glass Condensate effective theory. Furthermore, we present simulation results using PythiaeRHIC to assess the feasibility of measuring the charm quark Sivers function at EicC. The simulation outcomes suggest that EicC, with its unique kinematic coverage, offers distinct advantages for probing the Sivers function, which would provide compelling evidence for the existence of the elusive spin-dependent odderon.
{"title":"Charm Sivers function at EicC","authors":"Senjie Zhu, Duxin Zheng, Lei Xia, Yifei Zhang","doi":"arxiv-2409.00653","DOIUrl":"https://doi.org/arxiv-2409.00653","url":null,"abstract":"The Electron-Ion Collider in China (EicC) is pivotal in enhancing our\u0000knowledge of the internal structure of nucleons and nuclei, particularly\u0000through the study of transverse momentum-dependent parton distributions (TMDs).\u0000Among the leading-twist TMDs, the Sivers function is of particular interest, as\u0000it provides crucial insights into the spin and momentum structure of hadrons\u0000and plays a significant role in describing transverse single spin asymmetries\u0000(SSAs) in high-energy scatterings. In this study, we focus on the theoretical framework and phenomenological\u0000implications of the Sivers function in the context of small-x physics, where it\u0000is intricately connected to the spin-dependent QCD odderon, demonstrating that\u0000the SSA can be expressed in terms of transverse momentum-dependent\u0000factorization within the Color Glass Condensate effective theory. Furthermore,\u0000we present simulation results using PythiaeRHIC to assess the feasibility of\u0000measuring the charm quark Sivers function at EicC. The simulation outcomes\u0000suggest that EicC, with its unique kinematic coverage, offers distinct\u0000advantages for probing the Sivers function, which would provide compelling\u0000evidence for the existence of the elusive spin-dependent odderon.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212805","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}
Edit Fenyvesi, Gábor Gyula Kiss, Dénes Molnár, Péter Lévai, Gergely Gábor Barnaföldi
The constancy of nuclear decay rates can be investigated via long-duration precision measurements. It is still an open question whether any (annual) modulation can be observed. Long-lasting nuclear decay rate measurements have been the subject of considerable research effort. A decay rate measurement with a 137Cs source is currently being conducted 30 meters below the ground at the J'anossy Underground Research Laboratory (JURLab, Csilleb'erc, Hungary) utilizing a High-purity Germanium (HPGe) detector. The laboratory is the low-radiation-background part of the Vesztergombi High Energy Laboratory (VLAB) on the KFKI campus, Csilleb'erc, Hungary. From October 2022 to April 2024, data of 18 months' worth have been collected, providing a new opportunity to look for variations in decay rates. The experimental setup, data processing method, and the first results of this measurement are presented here.
{"title":"Status report on long-time decay measurements of 137Cs radioisotope","authors":"Edit Fenyvesi, Gábor Gyula Kiss, Dénes Molnár, Péter Lévai, Gergely Gábor Barnaföldi","doi":"arxiv-2409.00182","DOIUrl":"https://doi.org/arxiv-2409.00182","url":null,"abstract":"The constancy of nuclear decay rates can be investigated via long-duration\u0000precision measurements. It is still an open question whether any (annual)\u0000modulation can be observed. Long-lasting nuclear decay rate measurements have\u0000been the subject of considerable research effort. A decay rate measurement with\u0000a 137Cs source is currently being conducted 30 meters below the ground at the\u0000J'anossy Underground Research Laboratory (JURLab, Csilleb'erc, Hungary)\u0000utilizing a High-purity Germanium (HPGe) detector. The laboratory is the\u0000low-radiation-background part of the Vesztergombi High Energy Laboratory (VLAB)\u0000on the KFKI campus, Csilleb'erc, Hungary. From October 2022 to April 2024,\u0000data of 18 months' worth have been collected, providing a new opportunity to\u0000look for variations in decay rates. The experimental setup, data processing\u0000method, and the first results of this measurement are presented here.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":"25 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212804","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}
Recent results from ALICE and CMS show a low-transverse-momentum enhancement of charm baryon-to-meson production ratios over model predictions based on e$^+$e$^-$ collisions. Several mechanisms are proposed to understand this phenomenon. New measurements by the LHCb and ALICE experiments show a similar enhancement in the beauty sector. We explore this enhancement in terms of event activity using the color-reconnection beyond leading order approximation model. We propose sensitive probes relying on the event shape that will allow for the differentiation between the proposed beauty-production scenarios using freshly collected LHC Run-3 data, and we also compare these to predictions for charm. Our results will contribute to a deeper theoretical understanding of the heavy-flavor baryon enhancement and its relation to baryon enhancement in general.
ALICE 和 CMS 的最新研究结果表明,与基于一$^+$e$^-$对撞的模型预测相比,粲重子与介子的生成比在低反向动量下有所提高。人们提出了几种机制来理解这一现象。大型强子对撞机b和ALICE实验的新测量结果表明,在美部门也有类似的增强。我们利用最新收集的 LHC Run-3 数据,提出了依赖于事件形状的灵敏探测器,以区分所提出的 "美 "产生情况,并将这些数据与对粲的预测进行了比较。我们的结果将有助于加深对重味重子增强及其与一般重子增强关系的理论理解。
{"title":"Event-activity-dependent beauty-baryon enhancement in simulations with color junctions","authors":"Lea Virág Földvári, Zoltán Varga, Róbert Vértesi","doi":"arxiv-2408.16447","DOIUrl":"https://doi.org/arxiv-2408.16447","url":null,"abstract":"Recent results from ALICE and CMS show a low-transverse-momentum enhancement\u0000of charm baryon-to-meson production ratios over model predictions based on\u0000e$^+$e$^-$ collisions. Several mechanisms are proposed to understand this\u0000phenomenon. New measurements by the LHCb and ALICE experiments show a similar\u0000enhancement in the beauty sector. We explore this enhancement in terms of event\u0000activity using the color-reconnection beyond leading order approximation model.\u0000We propose sensitive probes relying on the event shape that will allow for the\u0000differentiation between the proposed beauty-production scenarios using freshly\u0000collected LHC Run-3 data, and we also compare these to predictions for charm.\u0000Our results will contribute to a deeper theoretical understanding of the\u0000heavy-flavor baryon enhancement and its relation to baryon enhancement in\u0000general.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212829","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}
Baryon quantum number is believed to be conserved since baryogenesis in the early Universe. While fractionally charged valence quarks are understood conventionally to each carry a baryon number of 1/3, the baryon junction, a non-perturbative Y-shaped topology of neutral gluons, has also been proposed as an alternative entity tracing the baryon number. Neither scenario has been verified experimentally. The STAR Collaboration reports measurements at mid-rapidity of baryon number ($boldsymbol{B}$) over the electric charge number difference ($boldsymbol{Delta Q}$) in isobar nuclear collisions, and the net-proton yield along rapidity in photonuclear collisions. A larger $boldsymbol{B/Delta Q}$ ratio and less asymmetric net-proton yield are observed than predicted from models assigning baryon number to valence quarks. These findings, corroborated by previous measurements in Au+Au collisions, disfavor the valence quark picture.
据信,重子量子数自早期宇宙的重子发生以来一直保持不变。虽然人们通常认为带分数电荷的价夸克各自携带的重子数为 1/3,但也有人提出了重子交界处,即中性胶子的非微扰 Y 形拓扑结构,作为追踪重子数的另一种实体。这两种设想都没有得到实验验证。STAR合作组织报告了等边核碰撞中重子数($boldsymbol{B}$)相对于电荷数差($boldsymbol{Delta Q}$)的中速测量结果,以及光子核碰撞中沿快速性的净质子产率。与将重子数赋予价夸克的模型所预测的相比,我们观测到了更大的($boldsymbol{B/Delta Q}$)比值和更少的不对称净质子产率。
{"title":"Tracking the baryon number with nuclear collisions","authors":"STAR Collaboration","doi":"arxiv-2408.15441","DOIUrl":"https://doi.org/arxiv-2408.15441","url":null,"abstract":"Baryon quantum number is believed to be conserved since baryogenesis in the\u0000early Universe. While fractionally charged valence quarks are understood\u0000conventionally to each carry a baryon number of 1/3, the baryon junction, a\u0000non-perturbative Y-shaped topology of neutral gluons, has also been proposed as\u0000an alternative entity tracing the baryon number. Neither scenario has been\u0000verified experimentally. The STAR Collaboration reports measurements at\u0000mid-rapidity of baryon number ($boldsymbol{B}$) over the electric charge\u0000number difference ($boldsymbol{Delta Q}$) in isobar nuclear collisions, and\u0000the net-proton yield along rapidity in photonuclear collisions. A larger\u0000$boldsymbol{B/Delta Q}$ ratio and less asymmetric net-proton yield are\u0000observed than predicted from models assigning baryon number to valence quarks.\u0000These findings, corroborated by previous measurements in Au+Au collisions,\u0000disfavor the valence quark picture.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":"59 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212826","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}
J. Ruotsalainen, D. A. Nesterenko, M. Stryjczyk, A. Kankainen, L. Al Ayoubi, O. Beliuskina, L. Canete, P. Chauveau, R. P. de Groote, P. Delahaye, T. Eronen, M. Flayol, Z. Ge, S. Geldhof, W. Gins, M. Hukkanen, A. Jaries, D. Kahl, D. Kumar, I. D. Moore, S. Nikas, H. Penttilä, D. Pitman-Weymouth, A. Raggio, S. Rinta-Antila, A. de Roubin, M. Vilen, V. Virtanen, M. Winter
The masses of the ground and isomeric states in $^{124,125}$Ag have been measured using the phase-imaging ion-cyclotron-resonance technique at the JYFLTRAP double Penning trap mass spectrometer. The ground states of $^{124}$Ag and $^{125}$Ag were found to be 30(250) keV and 250(430) keV less bound but 36 and 110 times more precise than in the Atomic Mass Evaluation 2020, respectively. The excitation energy of $^{124}$Ag$^{m}$, ${E_x = 188.2(25)}$ keV, was determined for the first time. The new precise mass values have been utilised to study the evolution of nuclear structure via two-neutron separation energies. The impact on the astrophysical rapid neutron capture process has been investigated via neutron-capture reaction rate calculations. The precision measurements indicate a more linear trend in two-neutron separation energies and reduce the mass-related uncertainties for the neutron-capture rate of $^{124}$Ag$(n,gamma)^{125}$Ag by a factor of around 100. The new mass values also improve the mass of $^{123}$Pd, previously measured using $^{124}$Ag as a reference.
{"title":"High-precision mass measurements of the ground and isomeric states in $^{124,125}$Ag","authors":"J. Ruotsalainen, D. A. Nesterenko, M. Stryjczyk, A. Kankainen, L. Al Ayoubi, O. Beliuskina, L. Canete, P. Chauveau, R. P. de Groote, P. Delahaye, T. Eronen, M. Flayol, Z. Ge, S. Geldhof, W. Gins, M. Hukkanen, A. Jaries, D. Kahl, D. Kumar, I. D. Moore, S. Nikas, H. Penttilä, D. Pitman-Weymouth, A. Raggio, S. Rinta-Antila, A. de Roubin, M. Vilen, V. Virtanen, M. Winter","doi":"arxiv-2408.14181","DOIUrl":"https://doi.org/arxiv-2408.14181","url":null,"abstract":"The masses of the ground and isomeric states in $^{124,125}$Ag have been\u0000measured using the phase-imaging ion-cyclotron-resonance technique at the\u0000JYFLTRAP double Penning trap mass spectrometer. The ground states of $^{124}$Ag\u0000and $^{125}$Ag were found to be 30(250) keV and 250(430) keV less bound but 36\u0000and 110 times more precise than in the Atomic Mass Evaluation 2020,\u0000respectively. The excitation energy of $^{124}$Ag$^{m}$, ${E_x = 188.2(25)}$\u0000keV, was determined for the first time. The new precise mass values have been\u0000utilised to study the evolution of nuclear structure via two-neutron separation\u0000energies. The impact on the astrophysical rapid neutron capture process has\u0000been investigated via neutron-capture reaction rate calculations. The precision\u0000measurements indicate a more linear trend in two-neutron separation energies\u0000and reduce the mass-related uncertainties for the neutron-capture rate of\u0000$^{124}$Ag$(n,gamma)^{125}$Ag by a factor of around 100. The new mass values\u0000also improve the mass of $^{123}$Pd, previously measured using $^{124}$Ag as a\u0000reference.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142226916","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}
S. V. Pineda, P. Chhetri, S. Bara, Y. Elskens, S. Casci, A. N. Alexandrova, M. Au, M. Athanasakis-Kaklamanakis, M. Bartokos, K. Beeks, C. Bernerd, A. Claessens, K. Chrysalidis, T. E. Cocolios, J. G. Correia, H. De Witte, R. Elwell, R. Ferrer, R. Heinke, E. R. Hudson, F. Ivandikov, Yu. Kudryavtsev, U. Köster, S. Kraemer, M. Laatiaoui, R. Lica, C. Merckling, I. Morawetz, H. W. T. Morgan, D. Moritz, L. M. C. Pereira, S. Raeder, S. Rothe, F. Schaden, K. Scharl, T. Schumm, S. Stegemann, J. Terhune, P. G. Thirolf, S. M. Tunhuma, P. Van Den Bergh, P. Van Duppen, A. Vantomme, U. Wahl, Z. Yue
A comparative vacuum ultraviolet spectroscopy study conducted at ISOLDE-CERN of the radiative decay of the $^{229m}$Th nuclear clock isomer embedded in different host materials is reported. The ratio of the number of radiative decay photons and the number of $^{229m}$Th embedded are determined for single crystalline CaF$_2$, MgF$_2$, LiSrAlF$_6$, AlN, and amorphous SiO$_2$. For the latter two materials, no radiative decay signal was observed and an upper limit of the ratio is reported. The radiative decay wavelength was determined in LiSrAlF$_6$ and CaF$_2$, reducing its uncertainty by a factor of 2.5 relative to our previous measurement. This value is in agreement with the recently reported improved values from laser excitation.
{"title":"Radiative Decay of the $^{229m}$Th Nuclear Clock Isomer in Different Host Materials","authors":"S. V. Pineda, P. Chhetri, S. Bara, Y. Elskens, S. Casci, A. N. Alexandrova, M. Au, M. Athanasakis-Kaklamanakis, M. Bartokos, K. Beeks, C. Bernerd, A. Claessens, K. Chrysalidis, T. E. Cocolios, J. G. Correia, H. De Witte, R. Elwell, R. Ferrer, R. Heinke, E. R. Hudson, F. Ivandikov, Yu. Kudryavtsev, U. Köster, S. Kraemer, M. Laatiaoui, R. Lica, C. Merckling, I. Morawetz, H. W. T. Morgan, D. Moritz, L. M. C. Pereira, S. Raeder, S. Rothe, F. Schaden, K. Scharl, T. Schumm, S. Stegemann, J. Terhune, P. G. Thirolf, S. M. Tunhuma, P. Van Den Bergh, P. Van Duppen, A. Vantomme, U. Wahl, Z. Yue","doi":"arxiv-2408.12309","DOIUrl":"https://doi.org/arxiv-2408.12309","url":null,"abstract":"A comparative vacuum ultraviolet spectroscopy study conducted at ISOLDE-CERN\u0000of the radiative decay of the $^{229m}$Th nuclear clock isomer embedded in\u0000different host materials is reported. The ratio of the number of radiative\u0000decay photons and the number of $^{229m}$Th embedded are determined for single\u0000crystalline CaF$_2$, MgF$_2$, LiSrAlF$_6$, AlN, and amorphous SiO$_2$. For the\u0000latter two materials, no radiative decay signal was observed and an upper limit\u0000of the ratio is reported. The radiative decay wavelength was determined in\u0000LiSrAlF$_6$ and CaF$_2$, reducing its uncertainty by a factor of 2.5 relative\u0000to our previous measurement. This value is in agreement with the recently\u0000reported improved values from laser excitation.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":"32 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212827","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}
K. Czerski, R. Dubey, A. Kowalska, G. Haridas Das, M. Kaczmarski, N. Targosz-Sleczka, M. Valat
A direct observation of the deuteron-deuteron (DD) fusion reaction at thermal meV energies, although theoretically possible, is not succeeded up to now. The electron screening effect that reduces the repulsive Coulomb barrier between reacting nuclei in metallic environments by several hundreds of eV and is additionally increased by crystal lattice defects in the hosting material, leads to strongly enhanced cross sections which means that this effect might be studied in laboratories. Here we present results of the 2H(d,p)3H reaction measurements performed on a ZrD2 target down to the lowest deuteron energy in the center mass system of 675 eV, using an ultra-high vacuum accelerator system, recently upgraded to achieve high beam currents at very low energies. The experimental thick target yield, decreasing over seven orders of magnitude for lowering beam energies, could be well described by the electron screening energy of 340 eV, which is much higher than the value of about 100 eV for a defect free material. At the energies below 2.5 keV, a constant plateau yield value could be observed. As indicated by significantly increased energies of emitted protons, this effect can be associated with the thermal DD fusion. A theoretical model explains the experimental observations by creation of ion tracks induced in the target by projectiles, and a high phonon density which locally increases temperature above the melting point. The nuclear reaction rate taking into account recently observed DD threshold resonance agrees very well with the experimental data.
{"title":"Observation of Thermal Deuteron-Deuteron Fusion in Ion Tracks","authors":"K. Czerski, R. Dubey, A. Kowalska, G. Haridas Das, M. Kaczmarski, N. Targosz-Sleczka, M. Valat","doi":"arxiv-2409.02112","DOIUrl":"https://doi.org/arxiv-2409.02112","url":null,"abstract":"A direct observation of the deuteron-deuteron (DD) fusion reaction at thermal\u0000meV energies, although theoretically possible, is not succeeded up to now. The\u0000electron screening effect that reduces the repulsive Coulomb barrier between\u0000reacting nuclei in metallic environments by several hundreds of eV and is\u0000additionally increased by crystal lattice defects in the hosting material,\u0000leads to strongly enhanced cross sections which means that this effect might be\u0000studied in laboratories. Here we present results of the 2H(d,p)3H reaction\u0000measurements performed on a ZrD2 target down to the lowest deuteron energy in\u0000the center mass system of 675 eV, using an ultra-high vacuum accelerator\u0000system, recently upgraded to achieve high beam currents at very low energies.\u0000The experimental thick target yield, decreasing over seven orders of magnitude\u0000for lowering beam energies, could be well described by the electron screening\u0000energy of 340 eV, which is much higher than the value of about 100 eV for a\u0000defect free material. At the energies below 2.5 keV, a constant plateau yield\u0000value could be observed. As indicated by significantly increased energies of\u0000emitted protons, this effect can be associated with the thermal DD fusion. A\u0000theoretical model explains the experimental observations by creation of ion\u0000tracks induced in the target by projectiles, and a high phonon density which\u0000locally increases temperature above the melting point. The nuclear reaction\u0000rate taking into account recently observed DD threshold resonance agrees very\u0000well with the experimental data.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":"32 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212832","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}
PHENIX Collaboration, N. J. Abdulameer, U. Acharya, C. Aidala, N. N. Ajitanand, Y. Akiba, R. Akimoto, J. Alexander, M. Alfred, V. Andrieux, S. Antsupov, K. Aoki, N. Apadula, H. Asano, E. T. Atomssa, T. C. Awes, B. Azmoun, V. Babintsev, M. Bai, X. Bai, N. S. Bandara, B. Bannier, E. Bannikov, K. N. Barish, S. Bathe, V. Baublis, C. Baumann, S. Baumgart, A. Bazilevsky, M. Beaumier, R. Belmont, A. Berdnikov, Y. Berdnikov, L. Bichon, D. Black, B. Blankenship, D. S. Blau, J. S. Bok, V. Borisov, K. Boyle, M. L. Brooks, J. Bryslawskyj, H. Buesching, V. Bumazhnov, S. Butsyk, S. Campbell, R. Cervantes, C. -H. Chen, D. Chen, M. Chiu, C. Y. Chi, I. J. Choi, J. B. Choi, S. Choi, P. Christiansen, T. Chujo, V. Cianciolo, Z. Citron, B. A. Cole, M. Connors, R. Corliss, N. Cronin, N. Crossette, M. Csanád, T. Csörgő, L. D'Orazio, T. W. Danley, A. Datta, M. S. Daugherity, G. David, K. DeBlasio, K. Dehmelt, A. Denisov, A. Deshpande, E. J. Desmond, L. Ding, A. Dion, D. Dixit, V. Doomra, J. H. Do, O. 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Jouan, D. S. Jumper, J. Kamin, S. Kanda, B. H. Kang, J. H. Kang, J. S. Kang, D. Kapukchyan, J. Kapustinsky, S. Karthas, D. Kawall, A. V. Kazantsev, J. A. Key, V. Khachatryan, P. K. Khandai, A. Khanzadeev, K. M. Kijima, C. Kim, D. J. Kim, E. -J. Kim, M. Kim, Y. -J. Kim, Y. K. Kim, D. Kincses, E. Kistenev, J. Klatsky, D. Kleinjan, P. Kline, T. Koblesky, M. Kofarago, B. Komkov, J. Koster, D. Kotchetkov, D. Kotov, L. Kovacs, F. Krizek, S. Kudo, K. Kurita, M. Kurosawa, Y. Kwon, Y. S. Lai, J. G. Lajoie, A. Lebedev, D. M. Lee, G. H. Lee, J. Lee, K. B. Lee, K. S. Lee, S. Lee, S. H. Lee, M. J. Leitch, M. Leitgab, Y. H. Leung, B. Lewis, S. H. Lim, M. X. Liu, X. Li, X. Li, V. -R. Loggins, S. Lokos, D. A. Loomis, K. Lovasz, D. Lynch, C. F. Maguire, T. Majoros, Y. I. Makdisi, M. Makek, A. Manion, V. I. Manko, E. Mannel, M. McCumber, P. L. McGaughey, D. McGlinchey, C. McKinney, A. Meles, M. Mendoza, B. Meredith, Y. Miake, T. Mibe, A. C. Mignerey, A. Milov, D. K. Mishra, J. T. Mitchell, M. Mitrankova, Iu. Mitrankov, G. Mitsuka, S. Miyasaka, S. Mizuno, A. K. Mohanty, S. Mohapatra, P. Montuenga, T. Moon, D. P. Morrison, M. Moskowitz, T. V. Moukhanova, B. Mulilo, T. Murakami, J. Murata, A. Mwai, T. Nagae, K. Nagai, S. Nagamiya, K. Nagashima, T. Nagashima, J. L. Nagle, M. I. Nagy, I. Nakagawa, Y. Nakamiya, K. R. Nakamura, T. Nakamura, K. Nakano, C. Nattrass, P. K. Netrakanti, M. Nihashi, T. Niida, R. Nouicer, N. Novitzky, T. Novák, G. Nukazuka, A. S. Nyanin, E. O'Brien, C. A. Ogilvie, H. Oide, K. Okada, J. D. Orjuela Koop, M. Orosz, J. D. Osborn, A. Oskarsson, G. J. Ottino, K. Ozawa, R. Pak, V. Pantuev, V. Papavassiliou, I. H. Park, J. S. Park, S. Park, S. K. Park, L. Patel, M. Patel, S. F. Pate, J. -C. Peng, D. V. Perepelitsa, G. D. N. Perera, D. Yu. Peressounko, C. E. PerezLara, J. Perry, R. Petti, M. Phipps, C. Pinkenburg, R. P. Pisani, M. Potekhin, M. L. Purschke, H. Qu, J. Rak, I. Ravinovich, K. F. Read, D. Reynolds, V. Riabov, Y. Riabov, E. Richardson, D. Richford, T. Rinn, N. Riveli, D. Roach, S. D. Rolnick, M. Rosati, Z. Rowan, M. S. Ryu, A. S. Safonov, B. Sahlmueller, N. Saito, T. Sakaguchi, H. Sako, V. Samsonov, M. Sarsour, S. Sato, S. Sawada, B. Schaefer, B. K. Schmoll, K. Sedgwick, J. Seele, R. Seidl, Y. Sekiguchi, A. Seleznev, A. Sen, R. Seto, P. Sett, A. Sexton, D. Sharma, A. Shaver, I. Shein, T. -A. Shibata, K. Shigaki, M. Shimomura, T. Shioya, K. Shoji, P. Shukla, A. Sickles, C. L. Silva, D. Silvermyr, B. K. Singh, C. P. Singh, V. Singh, M. Skolnik, M. Slunečka, K. L. Smith, M. Snowball, S. Solano, R. A. Soltz, W. E. Sondheim, S. P. Sorensen, I. V. Sourikova, P. W. Stankus, P. Steinberg, E. Stenlund, M. Stepanov, A. Ster, S. P. Stoll, M. R. Stone, T. Sugitate, A. Sukhanov, T. Sumita, J. Sun, Z. Sun, J. Sziklai, A. Takahara, A. Taketani, Y. Tanaka, K. Tanida, M. J. Tannenbaum, S. Tarafdar, A. Taranenko, G. Tarnai, E. Tennant, R. Tieulent, A. Timilsina, T. Todoroki, M. Tomášek, H. Torii, C. L. Towell, R. S. Towell, I. Tserruya, Y. Ueda, B. Ujvari, H. W. van Hecke, M. Vargyas, E. Vazquez-Zambrano, A. Veicht, J. Velkovska, M. Virius, V. Vrba, N. Vukman, E. Vznuzdaev, R. Vértesi, X. R. Wang, D. Watanabe, K. Watanabe, Y. Watanabe, Y. S. Watanabe, F. Wei, S. Whitaker, S. Wolin, C. L. Woody, M. Wysocki, B. Xia, L. Xue, C. Xu, Q. Xu, S. Yalcin, Y. L. Yamaguchi, H. Yamamoto, A. Yanovich, S. Yokkaichi, I. Yoon, J. H. Yoo, I. Younus, Z. You, I. E. Yushmanov, H. Yu, W. A. Zajc, A. Zelenski, S. Zhou, L. Zou
The jet cross-section and jet-substructure observables in $p$$+$$p$ collisions at $sqrt{s}=200$ GeV were measured by the PHENIX Collaboration at the Relativistic Heavy Ion Collider (RHIC). Jets are reconstructed from charged-particle tracks and electromagnetic-calorimeter clusters using the anti-$k_{t}$ algorithm with a jet radius $R=0.3$ for jets with transverse momentum within $8.0