Astroparticle Physics最新文献

{"title":"Bulk viscous cosmological model in f(T,T) modified gravity","authors":"Raja Solanki, Aaqid Bhat, P.K. Sahoo","doi":"10.1016/j.astropartphys.2024.103013","DOIUrl":"10.1016/j.astropartphys.2024.103013","url":null,"abstract":"<div><p>This article explores the impact of bulk viscosity on understanding the universe’s accelerated expansion within the context of modified <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>T</mi><mo>,</mo><mi>T</mi><mo>)</mo></mrow></mrow></math></span> gravity, which is an extension of the <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>T</mi><mo>)</mo></mrow></mrow></math></span> gravitational theory, allowing a broad coupling between the energy–momentum scalar <span><math><mi>T</mi></math></span> and the torsion scalar <span><math><mi>T</mi></math></span>. We consider two <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>T</mi><mo>,</mo><mi>T</mi><mo>)</mo></mrow></mrow></math></span> functions, specifically <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>T</mi><mo>,</mo><mi>T</mi><mo>)</mo></mrow><mo>=</mo><mi>α</mi><mi>T</mi><mo>+</mo><mi>β</mi><mi>T</mi></mrow></math></span> and <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>T</mi><mo>,</mo><mi>T</mi><mo>)</mo></mrow><mo>=</mo><mi>α</mi><msqrt><mrow><mo>−</mo><mi>T</mi></mrow></msqrt><mo>+</mo><mi>β</mi><mi>T</mi></mrow></math></span>, where <span><math><mi>α</mi></math></span> and <span><math><mi>β</mi></math></span> are arbitrary constants, along with the fluid part incorporating the coefficient of bulk viscosity <span><math><mrow><mi>ζ</mi><mo>=</mo><msub><mrow><mi>ζ</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>></mo><mn>0</mn></mrow></math></span>. We calculate the analytical solutions of the corresponding field equations for a flat FLRW environment, and then we constrain the free parameters of the obtained solution using CC, Pantheon+, and the CC+Pantheon+ samples. We perform the Bayesian statistical analysis to estimate the posterior probability utilizing the likelihood function and the MCMC random sampling technique. Further, to assess the effectiveness of our MCMC analysis, we estimate the corresponding AIC and BIC values, and we find that there is strong evidence supporting the assumed viscous modified gravity models for all three data sets. Also, we find that the linear model precisely mimics the <span><math><mi>Λ</mi></math></span>CDM model. We also investigate the evolutionary behavior of some prominent cosmological parameters. We observe that the effective equation of state parameter for both models predict the accelerating behavior of the cosmic expansion phase. In addition, from the statefinder test, we find that the parameters of the considered MOG models favor the quintessence-type behavior. Further, we observe that the behavior of <span><math><mrow><mi>O</mi><mi>m</mi><mrow><mo>(</mo><mi>z</mi><mo>)</mo></mrow></mrow></math></span> curves corresponding to both models represent a consistent negative slope across the entire domain. We infer that our cosmological setting utilizing <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>T</mi><mo>,</mo><mi>T</mi><mo>)</mo></mrow></mrow></math></span> gravity models with the viscous matter fluid embodies quintessence-like behavior","PeriodicalId":55439,"journal":{"name":"Astroparticle Physics","volume":"163 ","pages":"Article 103013"},"PeriodicalIF":4.2,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141851661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Observational constrained Weyl type f(Q,T) gravity cosmological model and the dynamical system analysis","authors":"Rahul Bhagat,&nbsp;B. Mishra","doi":"10.1016/j.astropartphys.2024.103011","DOIUrl":"10.1016/j.astropartphys.2024.103011","url":null,"abstract":"<div><p>Using the cosmological date sets, the cosmological parameters are constrained in this paper, with well known phantom behavioural Hubble parameter. To understand the dynamics of the Weyl type <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>Q</mi><mo>,</mo><mi>T</mi><mo>)</mo></mrow></mrow></math></span> gravity, functional form of <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>Q</mi><mo>,</mo><mi>T</mi><mo>)</mo></mrow></mrow></math></span> has been introduced, where <span><math><mi>Q</mi></math></span> and <span><math><mi>T</mi></math></span> respectively represents the nonmetricity scalar that depends on the Weyl vector <span><math><mrow><mo>(</mo><mi>Q</mi><mo>=</mo><mo>−</mo><mn>6</mn><msup><mrow><mi>w</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>)</mo></mrow></math></span> and trace of energy–momentum tensor. Using the constrained values of the parameters, the other geometrical parameters are analysed and the accelerating behaviour has been shown. The dynamical parameters and energy conditions are also analysed. Further to get the complete evolutionary behaviour of the Universe, the dynamical system analysis has been performed.</p></div>","PeriodicalId":55439,"journal":{"name":"Astroparticle Physics","volume":"163 ","pages":"Article 103011"},"PeriodicalIF":4.2,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141847877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geometric Hawking radiation of Schwarzschild Black Hole with novel quantum algebra","authors":"Mauricio Bellini ,&nbsp;Juan Ignacio Musmarra ,&nbsp;Daniela Magos Cortes","doi":"10.1016/j.astropartphys.2024.103010","DOIUrl":"10.1016/j.astropartphys.2024.103010","url":null,"abstract":"<div><p>In the context of an extended General Relativity theory with boundary terms included, we introduce a new nonlinear quantum algebra involving a quantum differential operator, with the aim to calculate quantum geometric alterations when a particle is created in the vicinity of a Schwarzschild black-hole by the Hawking radiation mechanism. The boundary terms in the varied action give rise to modifications in the geometric background, which are investigated by analyzing the metric tensor and the Ricci curvature within the framework of a renormalized quantum theory of gravity.</p></div>","PeriodicalId":55439,"journal":{"name":"Astroparticle Physics","volume":"163 ","pages":"Article 103010"},"PeriodicalIF":4.2,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141623270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A hybrid approach to event reconstruction for atmospheric Cherenkov Telescopes combining machine learning and likelihood fitting","authors":"Georg Schwefer ,&nbsp;Robert Parsons ,&nbsp;Jim Hinton","doi":"10.1016/j.astropartphys.2024.103008","DOIUrl":"https://doi.org/10.1016/j.astropartphys.2024.103008","url":null,"abstract":"<div><p>The imaging atmospheric Cherenkov technique provides potentially the highest angular resolution achievable in astronomy at energies above the X-ray waveband. High-resolution measurements provide the key to progress on many of the major questions in high energy astrophysics, including the sites and mechanisms of particle acceleration to PeV energies. The huge potential of the next-generation CTA observatory in this regard can be realised with the help of improved algorithms for the reconstruction of the air-shower direction and energy.</p><p>Hybrid methods combining maximum-likelihood-fitting techniques with neural networks represent a particularly promising approach and have recently been successfully applied for the reconstruction of astrophysical neutrinos. Here, we present the <em>FreePACT</em> algorithm, a hybrid reconstruction method for IACTs. In this, making use of the neural ratio estimation technique from the field of likelihood-free inference, the analytical likelihood used in traditional image likelihood fitting is replaced by a neural network that approximates the charge probability density function for each pixel in the camera.</p><p>The performance of this improved algorithm is demonstrated using simulations of the planned CTA southern array. For this setup<em>FreePACT</em> provides significant performance improvements over analytical likelihood techniques, with improvements in angular and energy resolution of 25% or more over a wide energy range and an angular resolution as low as <span><math><mrow><mtext>40</mtext><mo>′</mo><mo>′</mo></mrow></math></span> at energies above <span><math><mrow><mn>50</mn><mspace></mspace><mi>TeV</mi></mrow></math></span> for observations at <span><math><mrow><mn>20</mn><mo>°</mo></mrow></math></span> zenith angle. It also yields more accurate estimations of the uncertainties on the reconstructed parameters and significantly speeds up the reconstruction compared to analytical likelihood techniques while showing the same stability with respect to changes in the observation conditions. Therefore, the <em>FreePACT</em> method is a promising upgrade over the current state-of-the-art likelihood event reconstruction techniques.</p></div>","PeriodicalId":55439,"journal":{"name":"Astroparticle Physics","volume":"163 ","pages":"Article 103008"},"PeriodicalIF":4.2,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0927650524000859/pdfft?md5=5e050cfcd2be1db5eef601e5935e2423&pid=1-s2.0-S0927650524000859-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141539234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Background study of the AMoRE-pilot experiment","authors":"A. Agrawal,&nbsp;V.V. Alenkov,&nbsp;P. Aryal,&nbsp;J. Beyer,&nbsp;B. Bhandari,&nbsp;R.S. Boiko,&nbsp;K. Boonin,&nbsp;O. Buzanov,&nbsp;C.R. Byeon,&nbsp;N. Chanthima,&nbsp;M.K. Cheoun,&nbsp;J.S. Choe,&nbsp;Seonho Choi,&nbsp;S. Choudhury,&nbsp;J.S. Chung,&nbsp;F.A. Danevich,&nbsp;M. Djamal,&nbsp;D. Drung,&nbsp;C. Enss,&nbsp;A. Fleischmann,&nbsp;Q. Yue","doi":"10.1016/j.astropartphys.2024.102991","DOIUrl":"https://doi.org/10.1016/j.astropartphys.2024.102991","url":null,"abstract":"<div><p>We report a study on the background of the Advanced Molybdenum-Based Rare process Experiment (AMoRE), a search for neutrinoless double beta decay (<span><math><mrow><mn>0</mn><mi>ν</mi><mi>β</mi><mi>β</mi></mrow></math></span>) of ¹⁰⁰Mo. The pilot stage of the experiment was conducted using <span><math><mo>∼</mo></math></span>1.9 kg of <span><math><msup><mrow></mrow><mrow><mn>48</mn><mi>depl</mi></mrow></msup></math></span>Ca<span><math><msup><mrow></mrow><mrow><mn>100</mn></mrow></msup></math></span>MoO<span><math><msub><mrow></mrow><mrow><mn>4</mn></mrow></msub></math></span> crystals at the Yangyang Underground Laboratory, South Korea, from 2015 to 2018. We compared the measured <span><math><mrow><mi>β</mi><mo>/</mo><mi>γ</mi></mrow></math></span> energy spectra in three experimental configurations with the results of Monte Carlo simulations and identified the background sources in each configuration. We replaced several detector components and enhanced the neutron shielding to lower the background level between configurations. A limit on the half-life of <span><math><mrow><mn>0</mn><mi>ν</mi><mi>β</mi><mi>β</mi></mrow></math></span> decay of ¹⁰⁰Mo was found at <span><math><mrow><msubsup><mrow><mi>T</mi></mrow><mrow><mn>1</mn><mo>/</mo><mn>2</mn></mrow><mrow><mn>0</mn><mi>ν</mi></mrow></msubsup><mo>≥</mo><mn>3</mn><mo>.</mo><mn>0</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>23</mn></mrow></msup></mrow></math></span> years at 90% confidence level, based on the measured background and its modeling. Further reduction of the background rate in the AMoRE-I and AMoRE-II are discussed.</p></div>","PeriodicalId":55439,"journal":{"name":"Astroparticle Physics","volume":"162 ","pages":"Article 102991"},"PeriodicalIF":3.5,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141290320","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measurements of low-energy, re-entrant albedo protons by the HEPD-01 space-borne detector","authors":"M. Martucci ,&nbsp;A. Oliva ,&nbsp;R. Battiston ,&nbsp;S. Beolé ,&nbsp;P. Cipollone ,&nbsp;A. Contin ,&nbsp;M. Cristoforetti ,&nbsp;C. De Donato ,&nbsp;C. De Santis ,&nbsp;A. Di Luca ,&nbsp;F.M. Follega ,&nbsp;G. Gebbia ,&nbsp;R. Iuppa ,&nbsp;A. Lega ,&nbsp;M. Lolli ,&nbsp;G. Masciantonio ,&nbsp;M. Mese ,&nbsp;C. Neubuser ,&nbsp;R. Nicolaidis ,&nbsp;F. Nozzoli ,&nbsp;P. Zuccon","doi":"10.1016/j.astropartphys.2024.102993","DOIUrl":"https://doi.org/10.1016/j.astropartphys.2024.102993","url":null,"abstract":"<div><p>Cosmic rays’ interactions with the residual atmosphere surrounding the Earth produce a variety of particles, like electrons, positrons, protons, anti-protons, and Helium nuclei that can be observed below the local geomagnetic cutoff. In this work, we present new measurements of downward-going, albedo proton fluxes with kinetic energy in the range <span><math><mo>∼</mo></math></span>40–<span><math><mo>∼</mo></math></span>250 MeV, performed by the High-Energy Particle Detector (HEPD-01) on board of the China Seismo-Electromagnetic Satellite - CSES-01 - at an altitude of <span><math><mo>∼</mo></math></span>500 km. Employing a dedicated trajectory-tracing simulation routine, the protons collected by HEPD-01 are classified into quasi-trapped (QT), long lifetime (<span><math><mo>≳</mo></math></span>10 s) particles concentrating in the equatorial region of the Earth, and un-trapped (UT), distributed at all latitudes; the latter includes both precipitating short lifetime particles (UT<span><math><msub><mrow></mrow><mrow><mi>S</mi></mrow></msub></math></span>) and pseudo-trapped long lifetime (UT<span><math><msub><mrow></mrow><mrow><mi>L</mi></mrow></msub></math></span>) populations, abundant in the so-called penumbra regions. The temporal trend of re-entrant protons between 2018 and 2022 is also reported, assessing the stability of such population during the data-taking period of HEPD-01; this highlights their independence from the long-term modulating effect of the solar activity.</p></div>","PeriodicalId":55439,"journal":{"name":"Astroparticle Physics","volume":"162 ","pages":"Article 102993"},"PeriodicalIF":3.5,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0927650524000707/pdfft?md5=512520925984998c3fc22b5efa40e593&pid=1-s2.0-S0927650524000707-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141264180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"The role of topological photon spheres in constraining the parameters of black holes","authors":"Jafar Sadeghi,&nbsp;Mohammad Ali S. Afshar","doi":"10.1016/j.astropartphys.2024.102994","DOIUrl":"https://doi.org/10.1016/j.astropartphys.2024.102994","url":null,"abstract":"<div><p>In this paper, we investigate the topological photon sphere from two distinct perspectives. In the first view, we examine the existence and characteristics of topological photon (anti-photon) spheres for black holes with different structures, such as Einstein–Young–Mills non-minimal, AdS black holes surrounded by Chaplygin-like dark fluid, and Bardeen-like black holes in Einstein–Gauss–Bonnet gravity. Furthermore, we delve into the deeper perspective of the necessity of photon spheres for super-compact gravitational structures such as black holes. By leveraging this necessity, we propose a classification of the parameter space of black hole models based on the existence and positioning of photon spheres. This approach enables the determination of parameter ranges that delineate whether a solution represents a black hole or a naked singularity. In essence, the paper illustrates the utility of the photon sphere as a notable test for establishing the permissible and non-permissible parameter ranges within specific theories of black hole solutions.</p></div>","PeriodicalId":55439,"journal":{"name":"Astroparticle Physics","volume":"162 ","pages":"Article 102994"},"PeriodicalIF":3.5,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141325696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stability analysis of wormhole solutions in f(Q) gravity utilizing Karmarkar condition with radial dependent redshift function","authors":"Sourav Chaudhary ,&nbsp;S.K. Maurya ,&nbsp;Jitendra Kumar ,&nbsp;Saibal Ray","doi":"10.1016/j.astropartphys.2024.103002","DOIUrl":"https://doi.org/10.1016/j.astropartphys.2024.103002","url":null,"abstract":"<div><p>In this work, we examine the properties of wormhole (WH) solutions in the context of modified <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>Q</mi><mo>)</mo></mrow></mrow></math></span> gravity. The shape function (<span><math><mrow><msub><mrow><mi>ξ</mi></mrow><mrow><mi>S</mi></mrow></msub><mrow><mo>(</mo><mi>r</mi><mo>)</mo></mrow></mrow></math></span>) and redshift function (<span><math><mrow><mi>ζ</mi><mrow><mo>(</mo><mi>r</mi><mo>)</mo></mrow></mrow></math></span>) are crucial in wormhole modeling since they determine the metric of a wormhole and define its attributes. The investigation provides the interaction between <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>Q</mi><mo>)</mo></mrow></mrow></math></span> gravity features and gravitational effects, guaranteeing insights into potential wormhole configurations. Subsequently, we have looked at the behavior of energy conditions and the fundamental properties of WHs. Additionally, the volume integral quantifier (<span><math><mi>V IQ</mi></math></span>) is addressed, providing insight into the quantity of exotic matter needed in the vicinity of the wormhole throat. Furthermore, the stability of the WH solutions in both cases is examined using the Tolman–Oppenheimer–Volkoff (TOV) equation where it is evident that both WH solutions meet the equilibrium requirements. Both cases ensures the real-world acceptability of WH solutions due to the rising nature of active gravitational mass (<span><math><msub><mrow><mi>M</mi></mrow><mrow><mi>a</mi><mi>c</mi><mi>t</mi><mi>i</mi><mi>v</mi><mi>e</mi></mrow></msub></math></span>). Our findings contribute to the current discussion about alternative gravity theories and exotic spacetime geometries.</p></div>","PeriodicalId":55439,"journal":{"name":"Astroparticle Physics","volume":"162 ","pages":"Article 103002"},"PeriodicalIF":4.2,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141482604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Differential Sensitivity of the KM3NeT/ARCA detector to a diffuse neutrino flux and to point-like source emission: Exploring the case of the Starburst Galaxies","authors":"S. Aiello ,&nbsp;A. Albert ,&nbsp;M. Alshamsi ,&nbsp;S. Alves Garre ,&nbsp;Z. Aly ,&nbsp;A. Ambrosone ,&nbsp;F. Ameli ,&nbsp;M. Andre ,&nbsp;E. Androutsou ,&nbsp;M. Anguita ,&nbsp;L. Aphecetche ,&nbsp;M. Ardid ,&nbsp;S. Ardid ,&nbsp;H. Atmani ,&nbsp;J. Aublin ,&nbsp;F. Badaracco ,&nbsp;L. Bailly-Salins ,&nbsp;Z. Bardačová ,&nbsp;B. Baret ,&nbsp;A. Bariego-Quintana ,&nbsp;N. Zywucka","doi":"10.1016/j.astropartphys.2024.102990","DOIUrl":"10.1016/j.astropartphys.2024.102990","url":null,"abstract":"<div><p>KM3NeT/ARCA is a Cherenkov neutrino telescope under construction in the Mediterranean sea, optimised for the detection of astrophysical neutrinos with energies above <span><math><mo>∼</mo></math></span>1 TeV. In this work, using Monte Carlo simulations including all-flavour neutrinos, the integrated and differential sensitivities for KM3NeT/ARCA are presented considering the case of a diffuse neutrino flux as well as extended and point-like neutrino sources. This analysis is applied to Starburst Galaxies demonstrating that the detector has the capability of tracing TeV neutrinos from these sources. Remarkably, after eight years, a hard power-law spectrum from the nearby Small Magellanic Cloud can be constrained. The sensitivity and discovery potential for NGC 1068 is also evaluated showing that KM3NeT/ARCA will discriminate between different astrophysical components of the measured neutrino flux after 3 years of data taking.</p></div>","PeriodicalId":55439,"journal":{"name":"Astroparticle Physics","volume":"162 ","pages":"Article 102990"},"PeriodicalIF":3.5,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0927650524000677/pdfft?md5=2f59c6bfde7fbc3aa2e3711ee9f85123&pid=1-s2.0-S0927650524000677-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141194993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Measurement of background radiations and spectra of X-ray sources using low-cost stratospheric balloon missions","authors":"Rupnath Sikdar,&nbsp;Sandip K. Chakrabarti,&nbsp;Debashis Bhowmick","doi":"10.1016/j.astropartphys.2024.103003","DOIUrl":"https://doi.org/10.1016/j.astropartphys.2024.103003","url":null,"abstract":"<div><p>In small balloon missions, some in situ radiation is added to the targeted strong persistent astronomical sources (such as, the Sun, Crab, Cygnus X-1, etc.) or transient sources, such as solar flares, gamma-ray bursts, etc., during their detection, i.e., the background radiation. For measurement and modeling of background radiation, we use the data of the low-cost, small, stratospheric, high-altitude balloon-borne missions conducted by Indian Centre for Space Physics. In this paper, we show several models to estimate the background counts where the strong X-ray sources are detected at the altitude range of <span><math><mrow><mo>∼</mo><mn>35</mn><mtext>–</mtext><mn>42</mn></mrow></math></span> km even in the absence of onboard pointing system and severe atmospheric absorption. For all data analysis purposes, the photons detected in the detector are in the energy range of <span><math><mrow><mn>10</mn><mtext>–</mtext><mn>80</mn></mrow></math></span> keV. Moreover, we found that the observed data is within <span><math><mrow><mo>±</mo><mn>1</mn><mi>σ</mi></mrow></math></span> of the calculated background model. Finally, using these background models, we estimate the spectra and luminosity of the Crab nebula and the black hole candidate Cygnus X-1, which agree with the previously published results.</p></div>","PeriodicalId":55439,"journal":{"name":"Astroparticle Physics","volume":"162 ","pages":"Article 103003"},"PeriodicalIF":4.2,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141482603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}