{"title":"Deflection angle and shadow of slowly rotating black holes in galactic nuclei","authors":"A. El Balali, M. Benali, M. Oualaid","doi":"10.1007/s10714-024-03205-z","DOIUrl":null,"url":null,"abstract":"<p>In this paper, we construct the slowly rotating case of an asymptotically flat supermassive black hole embedded in dark matter using Newman–Janis procedure. Our analysis is carried with respect to the involved parameters including the halo total mass <i>M</i> and the galaxy’s lengthscale <span>\\(a_0\\)</span>. Concretly, we investigate the dark matter impact on the effective potential and the photon sphere. In particular, we find that the lengthscale <span>\\(a_0\\)</span> controles such potential values. Indeed, for low <span>\\(a_0\\)</span> values, we find that the halo total mass <i>M</i> decreases the potential values significantly while for high <span>\\(a_0\\)</span> values such impact is diluted. Regarding the shadow aspects, we show that the shadow size is much smaller for high values of <span>\\(a_0\\)</span> while the opposite effect is observed when the halo total mass <i>M</i> is increased. By comparing our case to the slowly rotating case, we notice that the former exhibits a shadow shifted from its center to the left side. Finally, we compute the deflection angle in the weak-limit approximation and inspect the dark matter parameters influence. By ploting such quantity, we observe that one should expect lower bending angle values for black holes in galactic nuclei.\n</p>","PeriodicalId":578,"journal":{"name":"General Relativity and Gravitation","volume":null,"pages":null},"PeriodicalIF":2.1000,"publicationDate":"2024-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"General Relativity and Gravitation","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1007/s10714-024-03205-z","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ASTRONOMY & ASTROPHYSICS","Score":null,"Total":0}
引用次数: 0
Abstract
In this paper, we construct the slowly rotating case of an asymptotically flat supermassive black hole embedded in dark matter using Newman–Janis procedure. Our analysis is carried with respect to the involved parameters including the halo total mass M and the galaxy’s lengthscale \(a_0\). Concretly, we investigate the dark matter impact on the effective potential and the photon sphere. In particular, we find that the lengthscale \(a_0\) controles such potential values. Indeed, for low \(a_0\) values, we find that the halo total mass M decreases the potential values significantly while for high \(a_0\) values such impact is diluted. Regarding the shadow aspects, we show that the shadow size is much smaller for high values of \(a_0\) while the opposite effect is observed when the halo total mass M is increased. By comparing our case to the slowly rotating case, we notice that the former exhibits a shadow shifted from its center to the left side. Finally, we compute the deflection angle in the weak-limit approximation and inspect the dark matter parameters influence. By ploting such quantity, we observe that one should expect lower bending angle values for black holes in galactic nuclei.
期刊介绍:
General Relativity and Gravitation is a journal devoted to all aspects of modern gravitational science, and published under the auspices of the International Society on General Relativity and Gravitation.
It welcomes in particular original articles on the following topics of current research:
Analytical general relativity, including its interface with geometrical analysis
Numerical relativity
Theoretical and observational cosmology
Relativistic astrophysics
Gravitational waves: data analysis, astrophysical sources and detector science
Extensions of general relativity
Supergravity
Gravitational aspects of string theory and its extensions
Quantum gravity: canonical approaches, in particular loop quantum gravity, and path integral approaches, in particular spin foams, Regge calculus and dynamical triangulations
Quantum field theory in curved spacetime
Non-commutative geometry and gravitation
Experimental gravity, in particular tests of general relativity
The journal publishes articles on all theoretical and experimental aspects of modern general relativity and gravitation, as well as book reviews and historical articles of special interest.