The bounds on parameters of the eV and higher scale sterile neutrinos from the $0nu beta beta$ decay have been refined and updated. We present a simple and compact analytic expression for the bound in the $Delta m^2_{41} - sin^2 2theta_{14}$ plane, which includes all relevant parameters. Dependencies of the bound on unknown CP-phases and the type of mass spectrum of light neutrinos (mass ordering and level of degeneracy) are studied in detail. We have computed the bounds using the latest and most stringent data from KamLAND-Zen. The projected constraints from future experiments are estimated. The obtained bounds are confronted with positive indications of the presence of sterile neutrinos as well as with the other existing bounds. The $0nu beta beta$ decay results exclude the regions of parameters implied by BEST and Neutrino-4, and the regions indicated by LSND and MiniBooNE are in conflict with $0nu beta beta$ results combined with $nu_mu-$ disappearance bounds.
我们完善并更新了来自$0nu beta beta$ 衰变的eV和更高尺度不育中微子的参数边界。我们为$Delta m^2_{41} 中的约束提出了一个简单紧凑的解析表达式。- sin^22theta_{14}$平面上的约束，其中包括所有相关参数。我们详细研究了边界对未知CP相位和轻中微子质量谱类型（质量排序和退化程度）的依赖关系。我们利用 KamLAND-Zen 最新、最严格的数据计算了边界。我们还估算了未来实验的预测约束。所得到的边界与立体中微子存在的积极迹象以及其他现有的边界相对抗。0 nu beta beta$ 衰变结果排除了 BEST 和中微子-4 所暗示的参数区域，而 LSND 和 MiniBooNE 所指示的区域与结合了 $nu_mu-$ 消失边界的 0 nu beta beta$ 结果相冲突。
{"title":"Restricting Sterile Neutrinos by Neutrinoless Double Beta Decay","authors":"Sudip Jana, Lucas Puetter, Alexei Yu. Smirnov","doi":"arxiv-2408.01488","DOIUrl":"https://doi.org/arxiv-2408.01488","url":null,"abstract":"The bounds on parameters of the eV and higher scale sterile neutrinos from\u0000the $0nu beta beta$ decay have been refined and updated. We present a simple\u0000and compact analytic expression for the bound in the $Delta m^2_{41} - sin^2\u00002theta_{14}$ plane, which includes all relevant parameters. Dependencies of\u0000the bound on unknown CP-phases and the type of mass spectrum of light neutrinos\u0000(mass ordering and level of degeneracy) are studied in detail. We have computed\u0000the bounds using the latest and most stringent data from KamLAND-Zen. The\u0000projected constraints from future experiments are estimated. The obtained\u0000bounds are confronted with positive indications of the presence of sterile\u0000neutrinos as well as with the other existing bounds. The $0nu beta beta$\u0000decay results exclude the regions of parameters implied by BEST and Neutrino-4,\u0000and the regions indicated by LSND and MiniBooNE are in conflict with $0nu\u0000beta beta$ results combined with $nu_mu-$ disappearance bounds.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141946142","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 possible use of optically pumped $^{199}$Hg nuclear spin magnetometry for fundamental physics studies, particularly in the search for electric dipole moments, remains of great interest. Understanding surface-induced relaxation is necessary for the development of both large- and small-volume cells that have a long and stable nuclear spin lifetime. Such cells are critical to several ongoing experiments, including the measurement of the neutron electric dipole moment, zero or otherwise. $^{199}$Hg, due to its large mass, has a multitude of bound surface states that affect the interaction time with the surface and are an important factor in the interpretation of previously acquired data. It is shown that the inclusion of these states brings consistency to the derived surface interaction properties.
{"title":"Bound surface states and the nuclear spin relaxation of $^{199}$Hg","authors":"S. K. Lamoreaux","doi":"arxiv-2408.08875","DOIUrl":"https://doi.org/arxiv-2408.08875","url":null,"abstract":"The possible use of optically pumped $^{199}$Hg nuclear spin magnetometry for\u0000fundamental physics studies, particularly in the search for electric dipole\u0000moments, remains of great interest. Understanding surface-induced relaxation is\u0000necessary for the development of both large- and small-volume cells that have a\u0000long and stable nuclear spin lifetime. Such cells are critical to several\u0000ongoing experiments, including the measurement of the neutron electric dipole\u0000moment, zero or otherwise. $^{199}$Hg, due to its large mass, has a multitude\u0000of bound surface states that affect the interaction time with the surface and\u0000are an important factor in the interpretation of previously acquired data. It\u0000is shown that the inclusion of these states brings consistency to the derived\u0000surface interaction properties.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212838","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}
Resmi K. Bharathan, Midhun C. V, M. M Musthafa, Sreena M, Silpa Ajaykumar, Farhana Thesni M. P, Swapna B, Vafiya Thaslim T. T, Shaima A, Nived K, Akhil R, Anagha P. K, Arunima Dev T. V, Keerthi E. S, Akshay K. S, Arun P. V, S. Ghugre
The cross sections for the $^{12}mathrm{C}(gamma,alpha)^{8}mathrm{Be}rightarrow 3alpha$ reaction have been successfully measured using exclusive coincidence between three $alpha$ particles, minimizing Compton background. Sequential breakup kinematics are evident, and the cross sections are presented as locally averaged histogram values. Theoretical textsc{Fresco} CDCC-CRC calculations reproduce the experimental data, showing that the process involves electromagnetic coupling to both $^{8}mathrm{Be}^{0^+}$ and $^{8}mathrm{Be}^{2^+}$ states. This study confirms that the $^{12}mathrm{C}(gamma,alpha)^{8}mathrm{Be}rightarrow 3alpha$ reaction proceeds via a sequential mechanism, crucial for understanding its significance in radiotherapy dosimetry.
{"title":"Measurement of the Sequential $3α$ Process in the Photodissociation of $^{12}mathrm{C}$","authors":"Resmi K. Bharathan, Midhun C. V, M. M Musthafa, Sreena M, Silpa Ajaykumar, Farhana Thesni M. P, Swapna B, Vafiya Thaslim T. T, Shaima A, Nived K, Akhil R, Anagha P. K, Arunima Dev T. V, Keerthi E. S, Akshay K. S, Arun P. V, S. Ghugre","doi":"arxiv-2407.19792","DOIUrl":"https://doi.org/arxiv-2407.19792","url":null,"abstract":"The cross sections for the\u0000$^{12}mathrm{C}(gamma,alpha)^{8}mathrm{Be}rightarrow 3alpha$ reaction\u0000have been successfully measured using exclusive coincidence between three\u0000$alpha$ particles, minimizing Compton background. Sequential breakup\u0000kinematics are evident, and the cross sections are presented as locally\u0000averaged histogram values. Theoretical textsc{Fresco} CDCC-CRC calculations\u0000reproduce the experimental data, showing that the process involves\u0000electromagnetic coupling to both $^{8}mathrm{Be}^{0^+}$ and\u0000$^{8}mathrm{Be}^{2^+}$ states. This study confirms that the\u0000$^{12}mathrm{C}(gamma,alpha)^{8}mathrm{Be}rightarrow 3alpha$ reaction\u0000proceeds via a sequential mechanism, crucial for understanding its significance\u0000in radiotherapy dosimetry.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141863838","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}
This paper reports the first measurement of the transverse momentum ($p_{mathrm{T}}$) spectra of primary charged pions, kaons, (anti)protons, and unidentified particles as a function of the charged-particle flattenicity in pp collisions at $sqrt{s}=13$ TeV. Flattenicity is a novel event shape observable that is measured in the pseudorapidity intervals covered by the V0 detector, $2.8
{"title":"Particle production as a function of charged-particle flattenicity in pp collisions at $sqrt{s}$ = 13 TeV","authors":"ALICE Collaboration","doi":"arxiv-2407.20037","DOIUrl":"https://doi.org/arxiv-2407.20037","url":null,"abstract":"This paper reports the first measurement of the transverse momentum\u0000($p_{mathrm{T}}$) spectra of primary charged pions, kaons, (anti)protons, and\u0000unidentified particles as a function of the charged-particle flattenicity in pp\u0000collisions at $sqrt{s}=13$ TeV. Flattenicity is a novel event shape observable\u0000that is measured in the pseudorapidity intervals covered by the V0 detector,\u0000$2.8<eta<5.1$ and $-3.7<eta<-1.7$. According to QCD-inspired phenomenological\u0000models, it shows sensitivity to multiparton interactions and is less affected\u0000by biases towards larger $p_{mathrm{T}}$ due to local multiplicity\u0000fluctuations in the V0 acceptance than multiplicity. The analysis is performed\u0000in minimum-bias (MB) as well as in high-multiplicity events up to\u0000$p_{mathrm{T}}=20$ GeV/$c$. The event selection requires at least one charged\u0000particle produced in the pseudorapidity interval $|eta|<1$. The measured\u0000$p_{mathrm{T}}$ distributions, average $p_{mathrm{T}}$, kaon-to-pion and\u0000proton-to-pion particle ratios, presented in this paper, are compared to model\u0000calculations using PYTHIA 8 based on color strings and EPOS LHC. The\u0000modification of the $p_{mathrm{T}}$-spectral shapes in low-flattenicity events\u0000that have large event activity with respect to those measured in MB events\u0000develops a pronounced peak at intermediate $p_{mathrm{T}}$\u0000($2<p_{mathrm{T}}<8$ GeV/$c$), and approaches the vicinity of unity at higher\u0000$p_{mathrm{T}}$. The results are qualitatively described by PYTHIA, and they\u0000show different behavior than those measured as a function of charged-particle\u0000multiplicity based on the V0M estimator.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141864022","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}
This paper describes a measurement of the jet radius dependence of the dijet momentum balance between leading back-to-back jets in 1.72 $nb^{-1}$ of Pb+Pb collisions collected in 2018 and 255 pb$^{-1}$ of $pp$ collisions collected in 2017 by the ATLAS detector at the LHC. Both data sets were collected at $ sqrt{s_{rm NN}}=$ 5.02 TeV. Jets are reconstructed using the anti-$k_t$ algorithm with jet radius parameters $R=$ 0.2, 0.3, 0.4, 0.5 and 0.6. The dijet momentum balance distributions are constructed for leading jets with transverse momentum $p_{rm T}$ from 100 to 562 GeV for $R=$ 0.2, 0.3 and 0.4 jets, and from 158 to 562 GeV for $R=$ 0.5 and 0.6 jets. The absolutely normalized dijet momentum balance distributions are constructed to compare measurements of the dijet yields in Pb+Pb collisions directly to the dijet cross sections in $pp$ collisions. For all jet radii considered here, there is a suppression of more balanced dijets in Pb+Pb collisions compared to $pp$ collisions, while for more imbalanced dijets there is an enhancement. There is a jet radius dependence to the dijet yields, being stronger for more imbalanced dijets than for more balanced dijets. Additionally, jet pair nuclear modification factors are measured. The subleading jet yields are found to be more suppressed than leading jet yields in dijets. A jet radius dependence of the pair nuclear modification factors is observed, with the suppression decreasing with increasing jet radius. These measurements provide new constraints on jet quenching scenarios in the quark-gluon plasma.
{"title":"Jet radius dependence of dijet momentum balance and suppression in Pb+Pb collisions at 5.02 TeV with the ATLAS detector","authors":"ATLAS Collaboration","doi":"arxiv-2407.18796","DOIUrl":"https://doi.org/arxiv-2407.18796","url":null,"abstract":"This paper describes a measurement of the jet radius dependence of the dijet\u0000momentum balance between leading back-to-back jets in 1.72 $nb^{-1}$ of Pb+Pb\u0000collisions collected in 2018 and 255 pb$^{-1}$ of $pp$ collisions collected in\u00002017 by the ATLAS detector at the LHC. Both data sets were collected at $\u0000sqrt{s_{rm NN}}=$ 5.02 TeV. Jets are reconstructed using the anti-$k_t$\u0000algorithm with jet radius parameters $R=$ 0.2, 0.3, 0.4, 0.5 and 0.6. The dijet\u0000momentum balance distributions are constructed for leading jets with transverse\u0000momentum $p_{rm T}$ from 100 to 562 GeV for $R=$ 0.2, 0.3 and 0.4 jets, and\u0000from 158 to 562 GeV for $R=$ 0.5 and 0.6 jets. The absolutely normalized dijet\u0000momentum balance distributions are constructed to compare measurements of the\u0000dijet yields in Pb+Pb collisions directly to the dijet cross sections in $pp$\u0000collisions. For all jet radii considered here, there is a suppression of more\u0000balanced dijets in Pb+Pb collisions compared to $pp$ collisions, while for more\u0000imbalanced dijets there is an enhancement. There is a jet radius dependence to\u0000the dijet yields, being stronger for more imbalanced dijets than for more\u0000balanced dijets. Additionally, jet pair nuclear modification factors are\u0000measured. The subleading jet yields are found to be more suppressed than\u0000leading jet yields in dijets. A jet radius dependence of the pair nuclear\u0000modification factors is observed, with the suppression decreasing with\u0000increasing jet radius. These measurements provide new constraints on jet\u0000quenching scenarios in the quark-gluon plasma.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141863828","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}
This review focuses on diffractive physics, which involves the long-range interactions of the strong nuclear force at high energies described by SU(3) gauge symmetry. It is expected that diffractive processes account for nearly 40% of the total cross-section at LHC energies. These processes consist of soft-scale physics where perturbation theory cannot be applied. Although highly successful and often described as a perfect theory, quantum chromodynamics relies heavily on perturbation theory, a model best suited for hard-scale physics. The study of pomerons could help bridge the soft and hard processes and provide a complete description of the theory of the strong interaction across the full momentum spectrum. Here, we will discuss some of the features of diffractive physics, experimental results from SPS, HERA, and the LHC, and where the field could potentially lead. With the recent publication of the odderon discovery in 2021 by the D0 and TOTEM collaborations and the new horizon of physics that lies ahead with the upcoming Electron-Ion Collider at Brookhaven National Laboratory, interest is seemingly piquing in high energy diffractive physics.
{"title":"SU(3) Gauge Symmetry: An Experimental Review of Diffractive Physics in e+p, p+p, p+A, and A+A Collision Systems","authors":"Krista L. Smith","doi":"arxiv-2407.16835","DOIUrl":"https://doi.org/arxiv-2407.16835","url":null,"abstract":"This review focuses on diffractive physics, which involves the long-range\u0000interactions of the strong nuclear force at high energies described by SU(3)\u0000gauge symmetry. It is expected that diffractive processes account for nearly\u000040% of the total cross-section at LHC energies. These processes consist of\u0000soft-scale physics where perturbation theory cannot be applied. Although highly\u0000successful and often described as a perfect theory, quantum chromodynamics\u0000relies heavily on perturbation theory, a model best suited for hard-scale\u0000physics. The study of pomerons could help bridge the soft and hard processes\u0000and provide a complete description of the theory of the strong interaction\u0000across the full momentum spectrum. Here, we will discuss some of the features\u0000of diffractive physics, experimental results from SPS, HERA, and the LHC, and\u0000where the field could potentially lead. With the recent publication of the\u0000odderon discovery in 2021 by the D0 and TOTEM collaborations and the new\u0000horizon of physics that lies ahead with the upcoming Electron-Ion Collider at\u0000Brookhaven National Laboratory, interest is seemingly piquing in high energy\u0000diffractive physics.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141771580","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. M. Gates, R. Orford, D. Rudolph, C. Appleton, B. M. Barrios, J. Y. Benitez, M. Bordeau, W. Botha, C. M. Campbell, J. Chadderton, A. T. Chemey, R. M. Clark, H. L. Crawford, J. D. Despotopulos, O. Dorvaux, N. E. Esker, P. Fallon, C. M. Folden III, B. J. P. Gall, F. H. Garcia, P. Golubev, J. A. Gooding, M. Grebo, K. E. Gregorich, M. Guerrero, R. A. Henderson, R. -D. Herzberg, Y. Hrabar, T. T. King, M. Kireeff Covo, A. S. Kirkland, R. Krücken, E. Leistenschneider, E. M. Lykiardopoulou, M. McCarthy, J. A. Mildon, C. Müller-Gatermann, L. Phair, J. L. Pore, 1 E. Rice, K. P. Rykaczewski, B. N. Sammis, L. G. Sarmiento, D. Seweryniak, D. K. Sharp, A. Sinjari, P. Steinegger, M. A. Stoyer, J. M. Szornel, K. Thomas, D. S. Todd, P. Vo, V. Watson, P. T. Wooddy
The $^{244}$Pu($^{50}$Ti,$xn$)$^{294-x}$Lv reaction was investigated at Lawrence Berkeley National Laboratory's 88-Inch Cyclotron facility. The experiment was aimed at the production of a superheavy element with $Zge 114$ by irradiating an actinide target with a beam heavier than $^{48}$Ca. Produced Lv ions were separated from the unwanted beam and nuclear reaction products using the Berkeley Gas-filled Separator and implanted into a newly commissioned focal plane detector system. Two decay chains were observed and assigned to the decay of $^{290}$Lv. The production cross section was measured to be $sigma_{rm prod}=0.44(^{+58}_{-28})$~pb at a center-of-target center-of-mass energy of 220(3)~MeV. This represents the first published measurement of the production of a superheavy element near the `Island-of-Stability', with a beam of $^{50}$Ti and is an essential precursor in the pursuit of searching for new elements beyond $Z=118$.
{"title":"Towards the Discovery of New Elements: Production of Livermorium (Z=116) with 50Ti","authors":"J. M. Gates, R. Orford, D. Rudolph, C. Appleton, B. M. Barrios, J. Y. Benitez, M. Bordeau, W. Botha, C. M. Campbell, J. Chadderton, A. T. Chemey, R. M. Clark, H. L. Crawford, J. D. Despotopulos, O. Dorvaux, N. E. Esker, P. Fallon, C. M. Folden III, B. J. P. Gall, F. H. Garcia, P. Golubev, J. A. Gooding, M. Grebo, K. E. Gregorich, M. Guerrero, R. A. Henderson, R. -D. Herzberg, Y. Hrabar, T. T. King, M. Kireeff Covo, A. S. Kirkland, R. Krücken, E. Leistenschneider, E. M. Lykiardopoulou, M. McCarthy, J. A. Mildon, C. Müller-Gatermann, L. Phair, J. L. Pore, 1 E. Rice, K. P. Rykaczewski, B. N. Sammis, L. G. Sarmiento, D. Seweryniak, D. K. Sharp, A. Sinjari, P. Steinegger, M. A. Stoyer, J. M. Szornel, K. Thomas, D. S. Todd, P. Vo, V. Watson, P. T. Wooddy","doi":"arxiv-2407.16079","DOIUrl":"https://doi.org/arxiv-2407.16079","url":null,"abstract":"The $^{244}$Pu($^{50}$Ti,$xn$)$^{294-x}$Lv reaction was investigated at\u0000Lawrence Berkeley National Laboratory's 88-Inch Cyclotron facility. The\u0000experiment was aimed at the production of a superheavy element with $Zge 114$\u0000by irradiating an actinide target with a beam heavier than $^{48}$Ca. Produced\u0000Lv ions were separated from the unwanted beam and nuclear reaction products\u0000using the Berkeley Gas-filled Separator and implanted into a newly commissioned\u0000focal plane detector system. Two decay chains were observed and assigned to the\u0000decay of $^{290}$Lv. The production cross section was measured to be\u0000$sigma_{rm prod}=0.44(^{+58}_{-28})$~pb at a center-of-target center-of-mass\u0000energy of 220(3)~MeV. This represents the first published measurement of the\u0000production of a superheavy element near the `Island-of-Stability', with a beam\u0000of $^{50}$Ti and is an essential precursor in the pursuit of searching for new\u0000elements beyond $Z=118$.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141771711","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}
We report on the first measurement of the elemental fragmentation cross sections (EFCSs) of $^{29-33}mathrm{Si}$ on a carbon target at $sim$230~MeV/nucleon. The experimental data covering charge changes of $Delta Z$ = 1-4 are reproduced well by the isospin-dependent quantum molecular dynamics (IQMD) coupled with the evaporation GEMINI (IQMD+GEMINI) model. We further explore the mechanisms underlying the single-proton removal reaction in this model framework. We conclude that the cross sections from direct proton knockout exhibit a overall weak dependence on the mass number of $mathrm{Si}$ projectiles. The proton evaporation induced after the projectile excitation significantly affects the cross sections for neutron-deficient $mathrm{Si}$ isotopes, while neutron evaporation plays a crucial role in the reactions of neutron-rich $mathrm{Si}$ isotopes. It is presented that the relative magnitude of one-proton and one-neutron separation energies is an essential factor that influences evaporation processes.
{"title":"Single-proton removal reaction in the IQMD+GEMINI model benchmarked by elemental fragmentation cross sections of $^{29-33}mathrm{Si}$ on carbon at $sim$230~MeV/nucleon","authors":"Guang-Shuai Li, Jun Su, Satoru Terashima, Jian-Wei Zhao, Er-Xi Xiao, Ji-Chao Zhang, Liu-Chun He, Ge Guo, Wei-Ping Lin, Wen-Jian Lin, Chuan-Ye Liu, Chen-Gui Lu, Bo Mei, Dan-Yang Pang, Ye-Lei Sun, Zhi-Yu Sun, Meng Wang, Feng Wang, Jing Wang, Shi-Tao Wang, Xiu-Lin Wei, Xiao-Dong Xu, Jun-Yao Xu, Li-Hua Zhu, Yong Zheng, Mei-Xue Zhang, Xue-Heng Zhang","doi":"arxiv-2407.14697","DOIUrl":"https://doi.org/arxiv-2407.14697","url":null,"abstract":"We report on the first measurement of the elemental fragmentation cross\u0000sections (EFCSs) of $^{29-33}mathrm{Si}$ on a carbon target at\u0000$sim$230~MeV/nucleon. The experimental data covering charge changes of $Delta\u0000Z$ = 1-4 are reproduced well by the isospin-dependent quantum molecular\u0000dynamics (IQMD) coupled with the evaporation GEMINI (IQMD+GEMINI) model. We\u0000further explore the mechanisms underlying the single-proton removal reaction in\u0000this model framework. We conclude that the cross sections from direct proton\u0000knockout exhibit a overall weak dependence on the mass number of $mathrm{Si}$\u0000projectiles. The proton evaporation induced after the projectile excitation\u0000significantly affects the cross sections for neutron-deficient $mathrm{Si}$\u0000isotopes, while neutron evaporation plays a crucial role in the reactions of\u0000neutron-rich $mathrm{Si}$ isotopes. It is presented that the relative\u0000magnitude of one-proton and one-neutron separation energies is an essential\u0000factor that influences evaporation processes.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141771614","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}
M. Sguazzin, B. Jurado, J. Pibernat, J. A. Swartz, M. Grieser, J. Glorius, Yu. A. Litvinov, C. Berthelot, B. Włoch, J. Adamczewski-Musch, P. Alfaurt, P. Ascher, L. Audouin, B. Blank, K. Blaum, B. Brückner, S. Dellmann, I. Dillmann, C. Domingo-Pardo, M. Dupuis, P. Erbacher, M. Flayol, O. Forstner, D. Freire-Fernández, M. Gerbaux, J. Giovinazzo, S. Grévy, C. J. Griffin, A. Gumberidze, S. Heil, A. Heinz, R. Hess, D. Kurtulgil, N. Kurz, G. Leckenby, S. Litvinov, B. Lorentz, V. Méot, J. Michaud, S. Pérard, N. Petridis, U. Popp, D. Ramos, R. Reifarth, M. Roche, M. S. Sanjari, R. S. Sidhu, U. Spillmann, M. Steck, Th. Stöhlker, B. Thomas, L. Thulliez, M. Versteegen
The probabilities for gamma-ray and particle emission as a function of the excitation energy of a decaying nucleus are valuable observables for constraining the ingredients of the models that describe the de-excitation of nuclei near the particle emission threshold. These models are essential in nuclear astrophysics and applications. In this work, we have for the first time simultaneously measured the gamma-ray and neutron emission probabilities of 208Pb. The measurement was performed in inverse kinematics at the Experimental Storage Ring (ESR) of the GSI/FAIR facility, where a 208Pb beam interacted through the 208Pb(p,p') reaction with a hydrogen gas jet target. Instead of detecting the gamma-rays and neutrons emitted by 208Pb, we detected the heavy beam-like residues produced after gamma and neutron emission. These heavy residues were fully separated by a dipole magnet of the ESR and were detected with outstanding efficiencies. The comparison of the measured probabilities with model calculations has allowed us to test different descriptions of the gamma-ray strength function and the nuclear level density available in the literature.
{"title":"First simultaneous measurement of the gamma-ray and neutron emission probabilities in inverse kinematics at a heavy-ion storage ring","authors":"M. Sguazzin, B. Jurado, J. Pibernat, J. A. Swartz, M. Grieser, J. Glorius, Yu. A. Litvinov, C. Berthelot, B. Włoch, J. Adamczewski-Musch, P. Alfaurt, P. Ascher, L. Audouin, B. Blank, K. Blaum, B. Brückner, S. Dellmann, I. Dillmann, C. Domingo-Pardo, M. Dupuis, P. Erbacher, M. Flayol, O. Forstner, D. Freire-Fernández, M. Gerbaux, J. Giovinazzo, S. Grévy, C. J. Griffin, A. Gumberidze, S. Heil, A. Heinz, R. Hess, D. Kurtulgil, N. Kurz, G. Leckenby, S. Litvinov, B. Lorentz, V. Méot, J. Michaud, S. Pérard, N. Petridis, U. Popp, D. Ramos, R. Reifarth, M. Roche, M. S. Sanjari, R. S. Sidhu, U. Spillmann, M. Steck, Th. Stöhlker, B. Thomas, L. Thulliez, M. Versteegen","doi":"arxiv-2407.14350","DOIUrl":"https://doi.org/arxiv-2407.14350","url":null,"abstract":"The probabilities for gamma-ray and particle emission as a function of the\u0000excitation energy of a decaying nucleus are valuable observables for\u0000constraining the ingredients of the models that describe the de-excitation of\u0000nuclei near the particle emission threshold. These models are essential in\u0000nuclear astrophysics and applications. In this work, we have for the first time\u0000simultaneously measured the gamma-ray and neutron emission probabilities of\u0000208Pb. The measurement was performed in inverse kinematics at the Experimental\u0000Storage Ring (ESR) of the GSI/FAIR facility, where a 208Pb beam interacted\u0000through the 208Pb(p,p') reaction with a hydrogen gas jet target. Instead of\u0000detecting the gamma-rays and neutrons emitted by 208Pb, we detected the heavy\u0000beam-like residues produced after gamma and neutron emission. These heavy\u0000residues were fully separated by a dipole magnet of the ESR and were detected\u0000with outstanding efficiencies. The comparison of the measured probabilities\u0000with model calculations has allowed us to test different descriptions of the\u0000gamma-ray strength function and the nuclear level density available in the\u0000literature.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141737313","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}
Measurements of the production yields of charm baryons ($Lambda_mathrm{c}^+$) and charm mesons (D$^0$) in proton-lead collisions at a nucleon-nucleon center-of-mass energy of 8.16 TeV are presented. The data were collected in 2016 with the CMS experiment and correspond to an integrated luminosity of 186 nb$^{-1}$. The $Lambda_mathrm{c}^+$ baryon is reconstructed from the decay channel $Lambda_mathrm{c}^+$ $to$ K$_mathrm{S}^0$, while the D$^0$ meson is reconstructed via D$^0$ $to$ K$^-$$pi^+$. The $Lambda_mathrm{c}^+$ baryon and D$^0$ meson yields are extracted in several charged-particle multiplicity classes. No strong multiplicity dependence of the $Lambda_mathrm{c}^+$-to-D$^0$ yield ratio is observed, unlike the observed strange baryon to strange meson yield ratio of $Lambda/bar{Lambda}$ to K$_mathrm{S}^0$, which shows a strong multiplicity dependence. This observation indicates different mechanisms for the multiplicity evolution of hadronization processes for charm and strange quarks and provides new constraints to the understanding of heavy flavor production and collectivity in small collision systems.
{"title":"Multiplicity dependence of charm baryon and baryon meson production in pPb collisions at $sqrt{s_mathrm{NN}}$ = 8.16 TeV","authors":"CMS Collaboration","doi":"arxiv-2407.13615","DOIUrl":"https://doi.org/arxiv-2407.13615","url":null,"abstract":"Measurements of the production yields of charm baryons\u0000($Lambda_mathrm{c}^+$) and charm mesons (D$^0$) in proton-lead collisions at\u0000a nucleon-nucleon center-of-mass energy of 8.16 TeV are presented. The data\u0000were collected in 2016 with the CMS experiment and correspond to an integrated\u0000luminosity of 186 nb$^{-1}$. The $Lambda_mathrm{c}^+$ baryon is reconstructed\u0000from the decay channel $Lambda_mathrm{c}^+$ $to$ K$_mathrm{S}^0$, while the\u0000D$^0$ meson is reconstructed via D$^0$ $to$ K$^-$$pi^+$. The\u0000$Lambda_mathrm{c}^+$ baryon and D$^0$ meson yields are extracted in several\u0000charged-particle multiplicity classes. No strong multiplicity dependence of the\u0000$Lambda_mathrm{c}^+$-to-D$^0$ yield ratio is observed, unlike the observed\u0000strange baryon to strange meson yield ratio of $Lambda/bar{Lambda}$ to\u0000K$_mathrm{S}^0$, which shows a strong multiplicity dependence. This\u0000observation indicates different mechanisms for the multiplicity evolution of\u0000hadronization processes for charm and strange quarks and provides new\u0000constraints to the understanding of heavy flavor production and collectivity in\u0000small collision systems.","PeriodicalId":501206,"journal":{"name":"arXiv - PHYS - Nuclear Experiment","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141737314","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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