In this work, we conduct a three-coupled-channel analysis of the $Z_c(3900)$ structure, focusing on the $Dbar{D}^*$, $J/psi pi$, and $rho eta_c$ channels, based on the one-boson exchange model. Drawing from previous study on the exotic state $T_{cc}$, we only utilize one more parameter to construct the interactions between the channels. Our model successfully reproduces the experimental line shapes of the invariant mass distribution at $sqrt{s} = 4.23$ and $4.26$ GeV for the three channels. Additionally, the finite-volume energy levels in our model show agreement with current LQCD conclusion. Detailed analysis suggests that the $Z_c(3900)$ peaks in the $pi J/psi$ and $rho eta_c$ distributions primarily arise from the triangle loop involving the $D_1 bar{D} D^*$ intermediate system. In the $Dbar{D}^*$ distribution, the threshold peak is generated by the cascade decay mechanism enhanced by a triangle diagram. Moreover, we find a virtual pole located far from the threshold, indicating that $Z_c(3900)$ peaks are not associated with physical pole. We conclude that the $Z_c(3900)$ peaks are predominantly caused by the threshold cusp.
{"title":"A Three-Coupled-Channel Analysis of $Z_c(3900)$ Involving $Dbar{D}^*$, $πJ/ψ$, and $ρη_c $","authors":"Kang Yu, Guang-Juan Wang, Jia-Jun Wu, Zhi Yang","doi":"arxiv-2409.10865","DOIUrl":"https://doi.org/arxiv-2409.10865","url":null,"abstract":"In this work, we conduct a three-coupled-channel analysis of the $Z_c(3900)$\u0000structure, focusing on the $Dbar{D}^*$, $J/psi pi$, and $rho eta_c$\u0000channels, based on the one-boson exchange model. Drawing from previous study on\u0000the exotic state $T_{cc}$, we only utilize one more parameter to construct the\u0000interactions between the channels. Our model successfully reproduces the\u0000experimental line shapes of the invariant mass distribution at $sqrt{s} =\u00004.23$ and $4.26$ GeV for the three channels. Additionally, the finite-volume\u0000energy levels in our model show agreement with current LQCD conclusion.\u0000Detailed analysis suggests that the $Z_c(3900)$ peaks in the $pi J/psi$ and\u0000$rho eta_c$ distributions primarily arise from the triangle loop involving\u0000the $D_1 bar{D} D^*$ intermediate system. In the $Dbar{D}^*$ distribution,\u0000the threshold peak is generated by the cascade decay mechanism enhanced by a\u0000triangle diagram. Moreover, we find a virtual pole located far from the\u0000threshold, indicating that $Z_c(3900)$ peaks are not associated with physical\u0000pole. We conclude that the $Z_c(3900)$ peaks are predominantly caused by the\u0000threshold cusp.","PeriodicalId":501067,"journal":{"name":"arXiv - PHYS - High Energy Physics - Phenomenology","volume":"82 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142258810","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 provides a complete set of analytic time-varying geodesic equations of the LTB black hole surrounded by the Quintom field. Indeed, we probe the evolution of the effective potential of such a black hole and possible photon orbits on cosmic epochs. We deduce that passing time in the accelerated universe from the early to late time epochs causes the peak of effective potential to decrease and shift to small radii, while the possibility of forming a stable orbit increases. Besides, four situations including: terminating bound orbit, stable orbit, scattering flyby orbit, and terminating escape orbit have been illustrated in some cosmic time slices. Moreover, changing orbits with time from the early universe to the late time epochs have been investigated. Furthermore, the stability of orbits and ISCO have been analyzed.
{"title":"History of a Particle Bounded to the Cosmological LTB Black Hole Surrounded by the Quintom Field","authors":"Sareh Eslamzadeh, Saheb Soroushfar","doi":"arxiv-2409.11318","DOIUrl":"https://doi.org/arxiv-2409.11318","url":null,"abstract":"This paper provides a complete set of analytic time-varying geodesic\u0000equations of the LTB black hole surrounded by the Quintom field. Indeed, we\u0000probe the evolution of the effective potential of such a black hole and\u0000possible photon orbits on cosmic epochs. We deduce that passing time in the\u0000accelerated universe from the early to late time epochs causes the peak of\u0000effective potential to decrease and shift to small radii, while the possibility\u0000of forming a stable orbit increases. Besides, four situations including:\u0000terminating bound orbit, stable orbit, scattering flyby orbit, and terminating\u0000escape orbit have been illustrated in some cosmic time slices. Moreover,\u0000changing orbits with time from the early universe to the late time epochs have\u0000been investigated. Furthermore, the stability of orbits and ISCO have been\u0000analyzed.","PeriodicalId":501067,"journal":{"name":"arXiv - PHYS - High Energy Physics - Phenomenology","volume":"188 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142258814","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 study the production of hypothetical vector particles, dark photons $gamma^prime$, with masses in the the range 0.4--1.8 GeV via inelastic proton bremsstrahlung. We further develop the approach of Refs. [1-3], where for the first time we considered the contributions to the cross section that are associated with the Pauli form factor in $ppgamma^prime$ vertex and obtained new splitting functions. We demonstrate numerically the importance of these corrections to full inelastic proton bremsstrahlung cross section and refine the sensitivity of the ongoing and future fixed target experiments T2K, DUNE and SHiP to the parameters of dark photon model. A dedicated experiment on measurements of the proton electromagnetic form factors in the time-like region below the proton-antiproton threshold, like those suggested in PANDA at FAIR, would help to obtain the robust predictions for the dark photon production by a proton beam at fixed target.
我们研究了通过非弹性质子衰斯拉发产生的质量在0.4--1.8 GeV范围内的假想矢量粒子--暗光子。我们进一步发展了参考文献[1-3]的方法,首次考虑了与$ppgamma^prime$顶点的保利形式因子相关的对截面的贡献,并获得了新的分裂函数。我们用数字证明了这些修正对全非弹性质子轫致辐射截面的重要性,并完善了正在进行的和未来的固定靶实验T2K、DUNE和SHiP对暗光子模型参数的敏感性。在质子-反质子阈值以下的类时间区域测量质子电磁形式因子的专门实验,就像在 FAIR 的 PANDA 中建议的那样,将有助于获得固定靶质子束产生暗光子的可靠预测。
{"title":"Pauli form factor contributions to the inelastic proton bremsstrahlung and dark photon production","authors":"Dmitry Gorbunov, Ekaterina Kriukova","doi":"arxiv-2409.11386","DOIUrl":"https://doi.org/arxiv-2409.11386","url":null,"abstract":"We study the production of hypothetical vector particles, dark photons\u0000$gamma^prime$, with masses in the the range 0.4--1.8 GeV via inelastic proton\u0000bremsstrahlung. We further develop the approach of Refs. [1-3], where for the\u0000first time we considered the contributions to the cross section that are\u0000associated with the Pauli form factor in $ppgamma^prime$ vertex and obtained\u0000new splitting functions. We demonstrate numerically the importance of these\u0000corrections to full inelastic proton bremsstrahlung cross section and refine\u0000the sensitivity of the ongoing and future fixed target experiments T2K, DUNE\u0000and SHiP to the parameters of dark photon model. A dedicated experiment on\u0000measurements of the proton electromagnetic form factors in the time-like region\u0000below the proton-antiproton threshold, like those suggested in PANDA at FAIR,\u0000would help to obtain the robust predictions for the dark photon production by a\u0000proton beam at fixed target.","PeriodicalId":501067,"journal":{"name":"arXiv - PHYS - High Energy Physics - Phenomenology","volume":"75 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142258818","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}
Konstantin Asteriadis, Sally Dawson, Pier Paolo Giardino, Robert Szafron
We systematically study potential effects of Beyond the Standard Model physics in the $e^+ e^- rightarrow Z H$ process. To this end, we include all relevant dimension-6 Standard Model Effective Field Theory operators and work to next-to-leading order (NLO) accuracy in the electroweak coupling. We consider both polarized and unpolarized electron and positron beams and present results for $sqrt{s}=240, ~365$ and $500~{rm GeV}$, emphasizing contributions where the NLO predictions differ significantly from the leading order results. At NLO, a sensitivity arises to operators that do not contribute at tree level, such as the Higgs trilinear coupling, CP-violating operators, and dimension-6 operators involving the top quark, among many others. We compare the prospects of future $e^+e^-$ colliders to explore these new physics effects with existing measurements from the LHC, electron EDMs (for CP violating operators), and Z pole measurements.
我们系统地研究了超越标准模型物理在 $e^+ e^-rightarrow Z H$ 过程中的潜在影响。为此,我们纳入了所有相关的六维度标准模型有效场论算子,并在电弱耦合方面达到了次领先阶(NLO)精度。我们同时考虑了极化和非极化电子束和正电子束,并给出了$sqrt{s}=240、~365$和$500~{rm GeV}$的结果,强调了NLO预测与先导阶结果有显著差异的地方。在NLO,对那些在树水平上没有贡献的算子产生了敏感性,比如希格斯三线耦合、违反CP的算子和涉及顶夸克的维-6算子等等。我们将未来e^+e^-$对撞机探索这些新物理效应的前景与现有的大型强子对撞机测量、电子EDM(针对违反CP的算子)和Zpole测量进行了比较。
{"title":"The $e^+ e^- rightarrow Z H$ Process in the SMEFT Beyond Leading Order","authors":"Konstantin Asteriadis, Sally Dawson, Pier Paolo Giardino, Robert Szafron","doi":"arxiv-2409.11466","DOIUrl":"https://doi.org/arxiv-2409.11466","url":null,"abstract":"We systematically study potential effects of Beyond the Standard Model\u0000physics in the $e^+ e^- rightarrow Z H$ process. To this end, we include all\u0000relevant dimension-6 Standard Model Effective Field Theory operators and work\u0000to next-to-leading order (NLO) accuracy in the electroweak coupling. We\u0000consider both polarized and unpolarized electron and positron beams and present\u0000results for $sqrt{s}=240, ~365$ and $500~{rm GeV}$, emphasizing contributions\u0000where the NLO predictions differ significantly from the leading order results.\u0000At NLO, a sensitivity arises to operators that do not contribute at tree level,\u0000such as the Higgs trilinear coupling, CP-violating operators, and dimension-6\u0000operators involving the top quark, among many others. We compare the prospects\u0000of future $e^+e^-$ colliders to explore these new physics effects with existing\u0000measurements from the LHC, electron EDMs (for CP violating operators), and Z\u0000pole measurements.","PeriodicalId":501067,"journal":{"name":"arXiv - PHYS - High Energy Physics - Phenomenology","volume":"19 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142258750","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 study the production of vector portal mediators, dark photons, with masses in the range 0.4--1.8,GeV in proton-proton collisions via the process of inelastic proton bremsstrahlung. In contrast to previous studies, we take into account the contribution of Pauli electromagnetic form factor to differential cross section and introduce two new splitting functions of the proton. We show that their contributions can become leading in the mass region 0.9--1.8,GeV and present the updated estimate for the sensitivity of the future SHiP experiment to visible decays of dark photons.
{"title":"Dark photon production via inelastic proton bremsstrahlung with Pauli form factor","authors":"Dmitry Gorbunov, Ekaterina Kriukova","doi":"arxiv-2409.11089","DOIUrl":"https://doi.org/arxiv-2409.11089","url":null,"abstract":"We study the production of vector portal mediators, dark photons, with masses\u0000in the range 0.4--1.8,GeV in proton-proton collisions via the process of\u0000inelastic proton bremsstrahlung. In contrast to previous studies, we take into\u0000account the contribution of Pauli electromagnetic form factor to differential\u0000cross section and introduce two new splitting functions of the proton. We show\u0000that their contributions can become leading in the mass region 0.9--1.8,GeV\u0000and present the updated estimate for the sensitivity of the future SHiP\u0000experiment to visible decays of dark photons.","PeriodicalId":501067,"journal":{"name":"arXiv - PHYS - High Energy Physics - Phenomenology","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142258809","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}
True muonium ($mu^+mu^-$) is one of the heaviest and smallest electromagnetic bound states not containing hadrons, and has never been observed so far. %Unlike atoms containing $tau$ particles, the muon lifetime is long enough to allow observation of true muonium (TM) decays and transitions. In this work it is shown that the spin-1 TM state (ortho-TM) can be observed at a discovery level of significance in three months at the CERN SPS North-Area H4A beam line, using 43.7 GeV secondary positrons. In this way, by impinging the positrons on multiple thin low-Z targets, ortho-TM, which decays predominantly to $e^+e^-$, can be produced from $e^+e^- to TM$ interaction on resonance ($sqrt{s} sim 2m_{mu}$).
{"title":"Feasibility study of True Muonium discovery with CERN-SPS H4 positron beam","authors":"Ruben Gargiulo, Elisa Di Meco, Stefano Palmisano","doi":"arxiv-2409.11342","DOIUrl":"https://doi.org/arxiv-2409.11342","url":null,"abstract":"True muonium ($mu^+mu^-$) is one of the heaviest and smallest\u0000electromagnetic bound states not containing hadrons, and has never been\u0000observed so far. %Unlike atoms containing $tau$ particles, the muon lifetime\u0000is long enough to allow observation of true muonium (TM) decays and\u0000transitions. In this work it is shown that the spin-1 TM state (ortho-TM) can\u0000be observed at a discovery level of significance in three months at the CERN\u0000SPS North-Area H4A beam line, using 43.7 GeV secondary positrons. In this way,\u0000by impinging the positrons on multiple thin low-Z targets, ortho-TM, which\u0000decays predominantly to $e^+e^-$, can be produced from $e^+e^- to TM$\u0000interaction on resonance ($sqrt{s} sim 2m_{mu}$).","PeriodicalId":501067,"journal":{"name":"arXiv - PHYS - High Energy Physics - Phenomenology","volume":"54 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142258813","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 cosmic gravitational focusing (CGF) of relic neutrinos can provide an independent measurement of the absolute neutrino masses $m_i$ with fourth-power dependence ($m^4_i$). We demonstrate in this paper for the first time how this can help identifying the neutrino mass ordering (NMO). Upon incorporating the projected CGF sensitivity at DESI, the preference for the normal ordering (NO) with a prior $sum m_nu > 0.509,{rm eV}$ would increase from the original 89.9% of the current clustering method with both DESI BAO and CMB to 98.2% while the inverted ordering (IO) is further disfavored from 10.1% to 1.8%. We also show how this can affect the prospects of the neutrinoless double beta decay and single beta decay measurements.
{"title":"Capability of Cosmic Gravitational Focusing on Identifying the Neutrino Mass Ordering","authors":"Shao-Feng Ge, Liang Tan","doi":"arxiv-2409.11115","DOIUrl":"https://doi.org/arxiv-2409.11115","url":null,"abstract":"The cosmic gravitational focusing (CGF) of relic neutrinos can provide an\u0000independent measurement of the absolute neutrino masses $m_i$ with fourth-power\u0000dependence ($m^4_i$). We demonstrate in this paper for the first time how this\u0000can help identifying the neutrino mass ordering (NMO). Upon incorporating the\u0000projected CGF sensitivity at DESI, the preference for the normal ordering (NO)\u0000with a prior $sum m_nu > 0.509,{rm eV}$ would increase from the original\u000089.9% of the current clustering method with both DESI BAO and CMB to 98.2%\u0000while the inverted ordering (IO) is further disfavored from 10.1% to 1.8%. We\u0000also show how this can affect the prospects of the neutrinoless double beta\u0000decay and single beta decay measurements.","PeriodicalId":501067,"journal":{"name":"arXiv - PHYS - High Energy Physics - Phenomenology","volume":"101 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142258868","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}
Fast radio bursts (FRBs) are enigmatic high-energy events with unknown origins, which are observationally divided into two categories, i.e., repeaters and non-repeaters. However, there are potentially a number of non-repeaters that may be misclassified, as repeating bursts are missed due to the limited sensitivity and observation periods, thus misleading the investigation of their physical properties. In this work, we propose a repeater identification method based on the t-distributed Stochastic Neighbor Embedding (t-SNE) algorithm and apply the classification to the first Canadian Hydrogen Intensity Mapping Experiment Fast Radio Burst (CHIME/FRB) catalog. We find that the spectral morphology parameters, specifically spectral running ($r$), represent the key features for identifying repeaters from the non-repeaters. Also, the results suggest that repeaters are more biased towards narrowband emission, whereas non-repeaters are inclined toward broadband emission. We provide a list of 163 repeater candidates, with $5$ of which are confirmed with an updated repeater catalog from CHIME/FRB. Our findings help to the understanding of the various properties underlying repeaters and non-repeaters, as well as guidelines for future FRB detection and categorization.
快速射电暴(FRBs)是起源不明的神秘高能事件,观测上将其分为两类,即重复暴和非重复暴。然而,由于灵敏度和观测周期的限制,重复爆发被遗漏,从而误导了对其物理特性的研究,因此可能有许多非重复爆发被错误分类。在这项工作中,我们提出了一种基于 t 分布随机邻域嵌入(t-SNE)算法的中继器识别方法,并将其应用于第一个加拿大氢强度绘图实验快速射电暴(CHIME/FRB)目录。我们发现,光谱形态参数,特别是光谱运行($r$),是识别中继器和非中继器的关键特征。同时,结果表明中继器更偏向于窄带发射,而非中继器则倾向于宽带发射。我们提供了一份 163 个中继器候选者名单,其中有 5 美元是通过 CHIME/FRB 更新的中继器目录确认的。我们的发现有助于理解中继器和非中继器的各种基本特性,并为未来的FRB探测和分类提供指导。
{"title":"Exploring the Key Features of Repeating Fast Radio Bursts with Machine Learning","authors":"Wan-Peng Sun, Ji-Guo Zhang, Yichao Li, Wan-Ting Hou, Fu-Wen Zhang, Jing-Fei Zhang, Xin Zhang","doi":"arxiv-2409.11173","DOIUrl":"https://doi.org/arxiv-2409.11173","url":null,"abstract":"Fast radio bursts (FRBs) are enigmatic high-energy events with unknown\u0000origins, which are observationally divided into two categories, i.e., repeaters\u0000and non-repeaters. However, there are potentially a number of non-repeaters\u0000that may be misclassified, as repeating bursts are missed due to the limited\u0000sensitivity and observation periods, thus misleading the investigation of their\u0000physical properties. In this work, we propose a repeater identification method\u0000based on the t-distributed Stochastic Neighbor Embedding (t-SNE) algorithm and\u0000apply the classification to the first Canadian Hydrogen Intensity Mapping\u0000Experiment Fast Radio Burst (CHIME/FRB) catalog. We find that the spectral\u0000morphology parameters, specifically spectral running ($r$), represent the key\u0000features for identifying repeaters from the non-repeaters. Also, the results\u0000suggest that repeaters are more biased towards narrowband emission, whereas\u0000non-repeaters are inclined toward broadband emission. We provide a list of 163\u0000repeater candidates, with $5$ of which are confirmed with an updated repeater\u0000catalog from CHIME/FRB. Our findings help to the understanding of the various\u0000properties underlying repeaters and non-repeaters, as well as guidelines for\u0000future FRB detection and categorization.","PeriodicalId":501067,"journal":{"name":"arXiv - PHYS - High Energy Physics - Phenomenology","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142258815","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}
A systematic and unified study of the ability of lifetime frontier experiments to explore the parameter space of hypothetical long-lived particles is one of the main steps in defining their parameter space. Such an analysis has not been conducted for dark photons -- hypothetical massive particles that have kinetic mixing with Standard Model photons. Existing studies have varied in their assumptions about dark photon phenomenology, often using outdated models that do not reflect recent advancements. In this paper, we present a unified calculation of the parameter space for GeV-scale dark photons probed by lifetime frontier experiments, delineating the regions excluded by past experiments and those accessible to future experiments. Our approach incorporates the latest advances in studying dark photon production mechanisms, including proton bremsstrahlung and mixing with neutral mesons, and utilizes the full palette of hadronic decays. Additionally, we explore the impact of uncertainties in proton bremsstrahlung on the dark photon parameter space, and find that they may severely affect the reach of many past and future experiments, including the maximal probed mass. The results are provided in a publicly accessible format, specifically through the implementation of the updated phenomenological models in texttt{SensCalc} - a unified tool for calculating event rates of new physics particles at lifetime frontier experiments, that has been supplemented by the module texttt{EventCalc} that samples events similar to traditional Monte Carlo generators.
{"title":"Searches for long-lived dark photons at proton accelerator experiments","authors":"Yehor Kyselov, Maksym Ovchynnikov","doi":"arxiv-2409.11096","DOIUrl":"https://doi.org/arxiv-2409.11096","url":null,"abstract":"A systematic and unified study of the ability of lifetime frontier\u0000experiments to explore the parameter space of hypothetical long-lived particles\u0000is one of the main steps in defining their parameter space. Such an analysis\u0000has not been conducted for dark photons -- hypothetical massive particles that\u0000have kinetic mixing with Standard Model photons. Existing studies have varied\u0000in their assumptions about dark photon phenomenology, often using outdated\u0000models that do not reflect recent advancements. In this paper, we present a\u0000unified calculation of the parameter space for GeV-scale dark photons probed by\u0000lifetime frontier experiments, delineating the regions excluded by past\u0000experiments and those accessible to future experiments. Our approach\u0000incorporates the latest advances in studying dark photon production mechanisms,\u0000including proton bremsstrahlung and mixing with neutral mesons, and utilizes\u0000the full palette of hadronic decays. Additionally, we explore the impact of\u0000uncertainties in proton bremsstrahlung on the dark photon parameter space, and\u0000find that they may severely affect the reach of many past and future\u0000experiments, including the maximal probed mass. The results are provided in a\u0000publicly accessible format, specifically through the implementation of the\u0000updated phenomenological models in texttt{SensCalc} - a unified tool for\u0000calculating event rates of new physics particles at lifetime frontier\u0000experiments, that has been supplemented by the module texttt{EventCalc} that\u0000samples events similar to traditional Monte Carlo generators.","PeriodicalId":501067,"journal":{"name":"arXiv - PHYS - High Energy Physics - Phenomenology","volume":"38 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142258808","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 propose a lepton seesaw model to get the same mass-origin of charged-leptons and neutrinos introducing a modular $A_4$ symmetry. In this scenario, the mass matrix of charged-leptons is induced via seesaw-like mechanism while the mass matrix of neutrino is realized via an inverse seesaw mechanism with help of vector-like fermions and an isospin singlet and triplet scalar field with nonzero vacuum expectation values. In analyzing the model we concentrate on fixed points of modulus $tau$ that is favored by a flux compactification of Type IIB string theory. We search for allowed region at nearby these fixed points and find good solutions at nearby $tau=omega$ with several good predictions.
{"title":"Lepton seesaw model in a modular $A_4$ symmetry","authors":"Takaaki Nomura, Hiroshi Okada","doi":"arxiv-2409.10912","DOIUrl":"https://doi.org/arxiv-2409.10912","url":null,"abstract":"We propose a lepton seesaw model to get the same mass-origin of\u0000charged-leptons and neutrinos introducing a modular $A_4$ symmetry. In this\u0000scenario, the mass matrix of charged-leptons is induced via seesaw-like\u0000mechanism while the mass matrix of neutrino is realized via an inverse seesaw\u0000mechanism with help of vector-like fermions and an isospin singlet and triplet\u0000scalar field with nonzero vacuum expectation values. In analyzing the model we\u0000concentrate on fixed points of modulus $tau$ that is favored by a flux\u0000compactification of Type IIB string theory. We search for allowed region at\u0000nearby these fixed points and find good solutions at nearby $tau=omega$ with\u0000several good predictions.","PeriodicalId":501067,"journal":{"name":"arXiv - PHYS - High Energy Physics - Phenomenology","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142258869","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}