The European Physical Journal C最新文献_第6页

Non-minimal coupling of scalar fields in the dark sector and generalization of the top-hat collapse

IF 4.2 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-04-04 DOI: 10.1140/epjc/s10052-025-14080-6

Priyanka Saha, Dipanjan Dey, Kaushik Bhattacharya

引用次数: 0

Slowly rotating black hole in chiral scalar–tensor theory 手性标量张量理论中的慢旋转黑洞

IF 4.2 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-04-04 DOI: 10.1140/epjc/s10052-025-14096-y

Ze-Kai Yu, Lei Liu, Tao Zhu

{"title":"Slowly rotating black hole in chiral scalar–tensor theory","authors":"Ze-Kai Yu, Lei Liu, Tao Zhu","doi":"10.1140/epjc/s10052-025-14096-y","DOIUrl":"10.1140/epjc/s10052-025-14096-y","url":null,"abstract":"<div><p>The chiral scalar–tensor theory is an extension of the Chern–Simons modified gravity by introducing couplings between the first and second derivatives of the scalar field and parity-violating spacetime curvatures. A key feature of this theory is its explicit breaking of parity symmetry in the gravitational sector, which is expected to affect the spatial-time component of axisymmetric spacetime. In this paper, we investigate the effects of the chiral scalar–tensor theory on slowly rotating black holes by building on known solutions in the dynamical Chern–Simons modified gravity. Using perturbative methods with small coupling and slow rotation approximations, we find that the contributions of the chiral scalar–tensor theory appear at quadratic order in the spin and cubic order in the coupling constants. Furthermore, we explore the properties of this solution in the weak field and check its ergosphere and horizon. In the weak limit, we find that the effects of parity violation are suppressed in the weak field but could become significant in the strong field regime. These results provide insights into the behavior of parity-violating gravity in the presence of rotation and may be used for further investigations into its observational signatures.\u0000</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 4","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14096-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143778091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Rescuing the Unruh effect in Lorentz violating gravity 拯救违反洛伦兹引力的乌鲁赫效应

IF 4.2 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-04-04 DOI: 10.1140/epjc/s10052-025-14099-9

F. Del Porro, M. Herrero-Valea, S. Liberati, M. Schneider

{"title":"Rescuing the Unruh effect in Lorentz violating gravity","authors":"F. Del Porro, M. Herrero-Valea, S. Liberati, M. Schneider","doi":"10.1140/epjc/s10052-025-14099-9","DOIUrl":"10.1140/epjc/s10052-025-14099-9","url":null,"abstract":"<div><p>While the robustness of Hawking radiation in the presence of UV Lorentz breaking is well-established, the Unruh effect has posed a challenge, with a large literature concluding that even the low-energy restoration of Lorentz invariance may not be sufficient to sustain this phenomenon. Notably, these previous studies have primarily focused on Lorentz-breaking matter on a conventional Rindler wedge. In this work, we demonstrate that considering the complete structure of Lorentz-breaking gravity, specifically the presence of a hypersurface orthogonal æther field, leads to the selection of a new Rindler wedge configuration characterized by a uniformly accelerated æther flow. This uniform acceleration provides a reference scale for comparison with the Lorentz-breaking one, thus ensuring the persistence of the Unruh effect in this context. We establish this by calculating the expected temperature using a Bogolubov approach, and by analyzing the response of a uniformly accelerated detector. We suggest that this resilience of the Unruh effect opens interesting possibilities towards future developments for using it as a tool to constrain Lorentz breaking theories of gravity.\u0000</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 4","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14099-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143778092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The constraint on modified black holes with extreme mass ratio inspirals 对具有极端质量比吸气的修正黑洞的约束

IF 4.2 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-04-04 DOI: 10.1140/epjc/s10052-025-14100-5

Chao Zhang, Guoyang Fu, Yungui Gong

{"title":"The constraint on modified black holes with extreme mass ratio inspirals","authors":"Chao Zhang, Guoyang Fu, Yungui Gong","doi":"10.1140/epjc/s10052-025-14100-5","DOIUrl":"10.1140/epjc/s10052-025-14100-5","url":null,"abstract":"<div><p>The low-energy effective action of String Theory introduces corrections to the dilaton-graviton sector, resulting in deformed black holes beyond general relativity. We analyze extreme mass-ratio inspiral systems (EMRIs), where a stellar-mass object spirals into a slowly rotating supermassive black hole including a distinct deviation parameter. This study examines the effects of this deformation on the rate of change of orbital energy and angular momentum, orbital evolution, and phase dynamics, incorporating leading-order post-Newtonian corrections. The String theory parameter <span>(alpha )</span> will accelerate the EMRI merger because of the extra energy and angular momentum fluxes carried away by corrections to the dilaton-graviton sector. With 1-year observations of EMRIs, we employ the Fisher information matrix method to evaluate the potential for detecting deviations from general relativity through space-based gravitational wave detectors that utilize time-delay interferometry to suppress laser noise. The constraint on modified black holes, <span>(varDelta alpha preceq 10^{-5})</span>, is almost the same with and without the time-delay interferometry combination. This analysis enhances our understanding and underscores the crucial role of observations in advancing gravitational phenomena within String Theory.\u0000</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 4","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14100-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143778113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effective temperatures of the QGP from thermal photon and dilepton production 热光子和二轻子产生的 QGP 有效温度

IF 4.2 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-04-04 DOI: 10.1140/epjc/s10052-025-14072-6

Olaf Massen, Govert Nijs, Mike Sas, Wilke van der Schee, Raimond Snellings

{"title":"Effective temperatures of the QGP from thermal photon and dilepton production","authors":"Olaf Massen, Govert Nijs, Mike Sas, Wilke van der Schee, Raimond Snellings","doi":"10.1140/epjc/s10052-025-14072-6","DOIUrl":"10.1140/epjc/s10052-025-14072-6","url":null,"abstract":"<div><p>Thermal electromagnetic radiation is emitted by the quark-gluon plasma (QGP) throughout its space-time evolution, with production rates that depend characteristically on the temperature. We study this temperature using thermal photons and dileptons using the <i>Trajectum</i> heavy ion code, which is constrained by Bayesian analysis. In addition we present the elliptic flow of both the thermal photons and thermal dileptons including systematic uncertainties corresponding to the model parameter uncertainty. We give a comprehensive overview of the resulting effective temperatures <span>(T_{textrm{eff}},)</span> obtained from thermal photon transverse momentum and thermal dilepton invariant mass distributions, as well as the dependence of <span>(T_{textrm{eff}})</span> on various selection criteria of these probes. We conclude that the <span>(T_{textrm{eff}})</span> obtained from thermal photons is mostly insensitive to the temperature of the QGP with a value of <span>(T_{textrm{eff}} sim 250)</span>–300 MeV depending on their transverse momentum, almost independent of collision centrality. Thermal dileptons are much better probes of the QGP temperature as they do not suffer from a blue shift as their invariant mass is used, allowing for a more precise constraint of the QGP temperature during different stages of the evolution of the system. By applying selection criteria on the dilepton transverse momentum and the invariant mass we are able to extract fluid temperatures on average times ranging from late emission <span>((langle tau rangle = 5.6~text {fm}/c))</span> to very early emissions <span>((langle tau rangle < 1.0~text {fm}/c).)</span> Furthermore, we show how these selection criteria can be used to map the elliptic flow of the system all throughout its evolution.\u0000</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 4","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14072-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143778090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Measuring the ATLAS ITk pixel detector material via multiple scattering of positrons at the CERN PS

IF 4.2 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-04-03 DOI: 10.1140/epjc/s10052-025-14092-2

Simon Florian Koch, Brian Moser, Antonín Lindner, Valerio Dao, Ignacio Asensi, Daniela Bortoletto, Marianne Brekkum, Florian Dachs, Hans Ludwig Joos, Milou van Rijnbach, Abhishek Sharma, Ismet Siral, Carlos Solans, Yingjie Wei

{"title":"Measuring the ATLAS ITk pixel detector material via multiple scattering of positrons at the CERN PS","authors":"Simon Florian Koch, Brian Moser, Antonín Lindner, Valerio Dao, Ignacio Asensi, Daniela Bortoletto, Marianne Brekkum, Florian Dachs, Hans Ludwig Joos, Milou van Rijnbach, Abhishek Sharma, Ismet Siral, Carlos Solans, Yingjie Wei","doi":"10.1140/epjc/s10052-025-14092-2","DOIUrl":"10.1140/epjc/s10052-025-14092-2","url":null,"abstract":"<div><p>The ITk is a new silicon tracker for the ATLAS experiment designed to increase detector resolution, readout capacity, and radiation hardness, in preparation for the larger number of simultaneous proton–proton interactions at the High Luminosity LHC. This paper presents the first direct measurement of the material budget of an ATLAS ITk pixel module, performed at a testbeam at the CERN Proton Synchrotron via the multiple scattering of low energy positrons within the module volume. Using a four plane telescope of thin monolithic pixel detectors from the MALTA Collaboration, scattering datasets were recorded at a beam energy of <span>(1.2,text {GeV})</span>. Kink angle distributions were extracted from tracks derived with and without information from the ITk pixel module, and were fit to extract the RMS scattering angle, which was converted to a fractional radiation length <span>(x/X_0)</span>. The average <span>(x/X_0)</span> across the module was measured as <span>([0.89 pm 0.01 text { (resolution)} pm 0.01 text { (subtraction)} ,,pm ,, 0.08 text {~(beam momentum band)}]%)</span>, which agrees within uncertainties with an estimate of <span>(0.88%)</span> derived from material component expectations.\u0000\u0000</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 4","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14092-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143769869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Topological constraints on general relativistic galaxy modelling

IF 4.2 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-04-03 DOI: 10.1140/epjc/s10052-025-14098-w

Marco Galoppo

引用次数: 0

Scalar NSI: a unique tool for constraining absolute neutrino masses via neutrino oscillations

IF 4.2 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-04-03 DOI: 10.1140/epjc/s10052-025-14089-x

Abinash Medhi, Arnab Sarker, Moon Moon Devi

{"title":"Scalar NSI: a unique tool for constraining absolute neutrino masses via neutrino oscillations","authors":"Abinash Medhi, Arnab Sarker, Moon Moon Devi","doi":"10.1140/epjc/s10052-025-14089-x","DOIUrl":"10.1140/epjc/s10052-025-14089-x","url":null,"abstract":"<div><p>In the standard interaction scenario, a direct measurement of absolute neutrino masses via neutrino oscillations is not feasible, as the oscillations depend only on the mass-squared differences. However,scalar non-standard interactions (SNSI) can introduce sub-dominant terms in the neutrino oscillation Hamiltonian that can directly affect the neutrino mass matrix, thereby making SNSI a unique tool for neutrino mass measurements. In this work, for the first time, we constrain the absolute masses of neutrinos by probing SNSI in a neutrino oscillation experiment. We show that a bound on the neutrino mass can be induced in the presence of SNSI at DUNE. We note that the constraints on the neutrino mass are much better for <span>(eta _{mu mu })</span> and <span>(eta _{tau tau })</span> as compared to <span>(eta _{ee})</span> for both NO and IO scenarios. We have also explored the constraints on the neutrino mass for different choices of <span>(delta _{CP})</span> and <span>(theta _{23})</span> for both neutrino mass orderings. This study shows that SNSI can serve as an interesting avenue to constrain the absolute neutrino masses in long-baseline neutrino experiments via neutrino oscillations.\u0000</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 4","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14089-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143769870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Particles dynamics with QPOs and thermodynamics features around a deformed anti-de sitter Schwarzschild black hole

IF 4.2 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-04-03 DOI: 10.1140/epjc/s10052-025-14081-5

Asifa Ashraf, Allah Ditta, Abdelmalek Bouzenada, Muhammad Aslam, Phongpichit Channuie, Farruh Atamurotov, M. Y. Malik

{"title":"Particles dynamics with QPOs and thermodynamics features around a deformed anti-de sitter Schwarzschild black hole","authors":"Asifa Ashraf, Allah Ditta, Abdelmalek Bouzenada, Muhammad Aslam, Phongpichit Channuie, Farruh Atamurotov, M. Y. Malik","doi":"10.1140/epjc/s10052-025-14081-5","DOIUrl":"10.1140/epjc/s10052-025-14081-5","url":null,"abstract":"<div><p>We explore the dynamics of test particles around a deformed anti-de Sitter Schwarzschild black hole and analyze the influence of model parameters on particle motion. Using the effective potential technique, we examine the stability of equatorial circular orbits. We obtain the analytical expressions for the energy and angular momentum of test particles, along with the innermost stable circular orbits and the effective forces acting upon the test particles. We also probe the epicyclic oscillations of test particles close to the equatorial plane and further evaluate analytical expressions for radial, vertical, and orbital frequencies, including the periastron precession frequency. Additionally, we study the thermal characteristics of the black hole, investigating its Gibbs free energy, emission energy, and check the influence of other thermodynamic properties on the black hole model. Our findings indicate that the model parameters <i>M</i>, <span>( Lambda )</span>, <span>( alpha )</span> and <span>( beta )</span> considerably affect both the particle motion including epicyclic oscillations and the thermodynamic behavior.\u0000</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 4","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14081-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143769872","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Detect anomalous quartic gauge couplings at muon colliders with quantum kernel k-means

IF 4.2 2区物理与天体物理

The European Physical Journal C Pub Date : 2025-04-02 DOI: 10.1140/epjc/s10052-025-14069-1

Shuai Zhang, Ke-Xin Chen, Ji-Chong Yang

{"title":"Detect anomalous quartic gauge couplings at muon colliders with quantum kernel k-means","authors":"Shuai Zhang, Ke-Xin Chen, Ji-Chong Yang","doi":"10.1140/epjc/s10052-025-14069-1","DOIUrl":"10.1140/epjc/s10052-025-14069-1","url":null,"abstract":"<div><p>In recent years, with the increasing luminosities of colliders, handling the growing amount of data has become a major challenge for future New Physics (NP) phenomenological research. In order to improve efficiency, machine learning algorithms have been introduced into the field of high-energy physics. As a machine learning algorithm, kernel k-means has been demonstrated to be useful for searching NP signals. It is well known that the kernel k-means algorithm can be carried out with the help of quantum computing, which suggests that quantum kernel k-means (QKKM) is also a potential tool for NP phenomenological studies in the future. This paper investigates how to search for NP signals using QKKM. Taking the <span>(mu ^+mu ^-rightarrow nu {bar{nu }}gamma gamma )</span> process at a muon collider as an example, the dimension-8 operators contributing to anomalous quartic gauge couplings (aQGCs) are studied. The expected coefficient constraints obtained using the QKKM of three different forms of quantum kernels, as well as the constraints obtained by the classical k-means algorithm are presented, and it can be shown that QKKM can help to find the signal of aQGCs. Comparing the classical k-means anomaly detection algorithm with QKKM, it is indicated that the QKKM is able to archive a better cut efficiency.\u0000</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 4","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14069-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0