Astrophysics and Space Science最新文献_第10页

An optimal deployment strategy for multi-plane satellite constellation using a generalized non-planar maneuver 使用广义非平面机动的多平面卫星星座优化部署战略

IF 1.8 4区物理与天体物理

Astrophysics and Space Science Pub Date : 2024-03-08 DOI: 10.1007/s10509-024-04288-5

Majid Bakhtiari, Ehsan Abbasali

{"title":"An optimal deployment strategy for multi-plane satellite constellation using a generalized non-planar maneuver","authors":"Majid Bakhtiari, Ehsan Abbasali","doi":"10.1007/s10509-024-04288-5","DOIUrl":"10.1007/s10509-024-04288-5","url":null,"abstract":"<div>Satellite constellation deployment is a cohesive mission where the trajectories of satellites must be planned concurrently. This paper presents an Integrated Program for Optimal Deployment of a Satellite Constellation (PODSC) consisting of (m) non-identical satellites in any desired arrangement in (n) orbital planes. The PODSC can optimize the scheduling of mission timelines, ensuring effective coordination with the trajectory of each satellite. This involves meticulous planning that considers temporal constraints and regards collision avoidance constraint. Additionally, the PODSC can select the most favorable deployment strategy, considering the trade-offs between time and fuel consumption across all possible deployment methods. The PODSC also utilizes an innovative Perturbed Multi-impulsive Inclined transfer trajectory Amalgamated with a modified Lambert targeting problem (PMIAL). The main idea of designing the mentioned maneuver is to eliminate the defects of the Lambert Targeting Problem (LTP). The LTP cannot account for space perturbations. Moreover, the LTP faces challenges when attempting to align the transfer trajectory tangentially with the final orbit in situations where there exists a substantial disparity in inclination and right ascension between the initial and final orbits. The PMIAL establishes three consecutive steps to fix the mentioned defects. Balancing the trade-off between time and achieving optimal fuel consumption will be possible by applying a hybrid IWO/PSO (The hybrid Invasive Weed Optimization/Particle Swarm Optimization) optimization algorithm in both PMIAL and PODSC. The case study will involve simulating two constellation deployment missions, with a particular focus on considering the Earth’s oblateness as a notable perturbation; however, the proposed algorithms can consider any space perturbations.</div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"369 3","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140070140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}

引用次数: 0

A perturbative approach to complexity during dissipative collapse 耗散坍缩过程中复杂性的微扰方法

IF 1.8 4区物理与天体物理

Astrophysics and Space Science Pub Date : 2024-03-05 DOI: 10.1007/s10509-024-04287-6

Megandhren Govender, Robert S. Bogadi, Wesley Govender, Narenee Mewalal

引用次数: 0

Correction to: Investigation of states switch properties of PSR J1946 + 1805 with the FAST 更正：用FAST研究PSR J1946 + 1805的状态开关特性

IF 1.8 4区物理与天体物理

Astrophysics and Space Science Pub Date : 2024-03-05 DOI: 10.1007/s10509-024-04289-4

Jie Tian, Xin Xu, Juntao Bai, Jiguang Lu, Lunhua Shang, Shi Dai, Dandan Zhang, Guojun Qiao, Rushang Zhao, Aijun Dong, Wenqian Zhong, Qijun Zhi, Shijun Dang

引用次数: 0

Wrong hypotheses in the generalized RTBP 广义 RTBP 中的错误假设

IF 1.8 4区物理与天体物理

Astrophysics and Space Science Pub Date : 2024-02-22 DOI: 10.1007/s10509-024-04286-7

Antonio Elipe

引用次数: 0

A review of 70 years with astrometry 天体测量学 70 年回顾

IF 1.8 4区物理与天体物理

Astrophysics and Space Science Pub Date : 2024-02-22 DOI: 10.1007/s10509-024-04285-8

Erik Høg

{"title":"A review of 70 years with astrometry","authors":"Erik Høg","doi":"10.1007/s10509-024-04285-8","DOIUrl":"10.1007/s10509-024-04285-8","url":null,"abstract":"<div>In 1953 I heard of an experiment in 1925 by Bengt Strömgren where he observed transit times with the meridian circle at the Copenhagen University Observatory measuring the current in a photocell behind slits when a star was crossing. In 1954 just 22 years old I was given the task as a student to make first test observations with a new meridian circle of the observatory. I became fascinated by the instrument and by the importance of astrometry for astronomy. Work at four meridian circles, two in Denmark, one in Hamburg, one in Lund, and Pierre Lacroute’s vision of space astrometry in France had by 1973 created the foundation for development of the Hipparcos satellite, and Gaia followed. In 2013 I proposed a successor satellite which has gained momentum especially thanks to the efforts of David Hobbs and it has a good chance to be launched by ESA about 2045. – But 70 years ago, optical astrometry was considered a dying branch of astronomy, unattractive compared with astrophysics. The following growth built on the still active interest in astrometry in Europe in those years and it was supported by ESA, the European Space Agency. – This review is only about astrometry where I was personally involved.</div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"369 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139947146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}

引用次数: 0

Investigation of states switch properties of PSR J1946 + 1805 with the FAST 利用 FAST 研究 PSR J1946 + 1805 的状态切换特性

IF 1.8 4区物理与天体物理

Astrophysics and Space Science Pub Date : 2024-02-20 DOI: 10.1007/s10509-024-04284-9

Jie Tian, Xin Xu, Juntao Bai, Jiguang Lu, Lunhua Shang, Shi Dai, Dandan Zhang, Guojun Qiao, Rushang Zhao, Aijun Dong, Wenqian Zhong, Qijun Zhi, Shijun Dang

{"title":"Investigation of states switch properties of PSR J1946 + 1805 with the FAST","authors":"Jie Tian, Xin Xu, Juntao Bai, Jiguang Lu, Lunhua Shang, Shi Dai, Dandan Zhang, Guojun Qiao, Rushang Zhao, Aijun Dong, Wenqian Zhong, Qijun Zhi, Shijun Dang","doi":"10.1007/s10509-024-04284-9","DOIUrl":"10.1007/s10509-024-04284-9","url":null,"abstract":"<div>We have carried out a detailed study of the single pulse of PSR J1946 + 1805 with the Five-hundred-meter Aperture Spherical radio Telescope (FAST). We reassessed the nulling fraction (NF) to be 57.5%. We also reverted the multiple drifting modes and obtained their drifting parameters. It is found that, for this pulsar, there exists the dwarf pulse at the beginning or end of the burst state, and the duration of dwarf pulse usually is one to two pulse periods. Additionally, we observed that there are scattered dwarf pulses detected in the null state. Detailed analysis of the fraction of linear polarization for all dwarf pulse is presented. It is worth noting that relative to normal pulses these dwarf pulses have a very high fraction of linear polarization, even more than 90%. We proposed that the dwarf pulses appearing at the beginning or end of the burst state may be a common behavior, which is important to understand the physical mechanism of the process of switching between two states.</div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"369 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139918590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}

引用次数: 0

Collision properties of overtaking magnetosonic solitary waves in the ionospheric multi-ion plasmas 电离层多离子等离子体中超越磁声波孤波的碰撞特性

IF 1.8 4区物理与天体物理

Astrophysics and Space Science Pub Date : 2024-02-09 DOI: 10.1007/s10509-024-04278-7

Dong-Ning Gao, Heng Zhang, Zhong-Zheng Li

引用次数: 0

New class of anisotropic charged strange quark star in Durgapal (IV) metric and its maximum mass 杜尔加帕尔IV元公设中的新一类各向异性带电奇异夸克星及其最大质量

IF 1.8 4区物理与天体物理

Astrophysics and Space Science Pub Date : 2024-02-05 DOI: 10.1007/s10509-024-04283-w

S. Sarkar, D. Bhattacharjee, K. B. Goswami, P. K. Chattopadhyay

{"title":"New class of anisotropic charged strange quark star in Durgapal (IV) metric and its maximum mass","authors":"S. Sarkar, D. Bhattacharjee, K. B. Goswami, P. K. Chattopadhyay","doi":"10.1007/s10509-024-04283-w","DOIUrl":"10.1007/s10509-024-04283-w","url":null,"abstract":"<div>In this paper, we have explored the relativistic stellar model considering pressure anisotropy. An anisotropic solution of the Einstein Field Equations (henceforth EFE) has been presented for charged strange quark stars considering the interior space-time geometry described by the Durgapal (IV^{th}) metric. In the case of a strange quark star, if the equation of state (p_{r}=frac{1}{3}(rho -4B_{g})) as prescribed in the MIT bag model is applicable, then at the surface, one may consider that the surface energy density (rho _{s}=4B_{g}). Imposing the constraint value of (B_{g}) within the range of 57.55 - (95.11~MeV/fm^{3}) required for stable quark matter with respect to a neutron when the external pressure is zero, we have determined the maximum mass and radius of the strange quark star and other relevant properties. It is noted that the maximum mass and radius for (B_{g}=57.55~MeV/fm^{3}) are (M_{max}=2.92M_{odot }) and (b_{max}=13.749~km), respectively, whereas those for (B_{g}=95.11~MeV/fm^{3}), are (M_{max}=2.27M_{odot }) and (b_{max}=10.695~km) for an isotropic uncharged star. In the presence of pressure anisotropy and charge, the value of maximum mass increases. We have predicted the radii of a few recently observed pulsars from our model and found that the radii agree with the predictions from observations. Furthermore, stability and energy conditions are also satisfied in the present model.</div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"369 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139690007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}

引用次数: 0

Multi-wavelength observation of MAXI J1348–630 during the outburst in 2019 2019年爆发期间对MAXI J1348-630的多波长观测

IF 1.8 4区物理与天体物理

Astrophysics and Space Science Pub Date : 2024-02-05 DOI: 10.1007/s10509-024-04280-z

Manoj Mandal, Debasish Saha, Sabyasachi Pal, Arijit Manna

{"title":"Multi-wavelength observation of MAXI J1348–630 during the outburst in 2019","authors":"Manoj Mandal, Debasish Saha, Sabyasachi Pal, Arijit Manna","doi":"10.1007/s10509-024-04280-z","DOIUrl":"10.1007/s10509-024-04280-z","url":null,"abstract":"<div>We study the multi-wavelength spectral properties of the black hole X-ray binary MAXI J1348–630 using quasi-simultaneous ALMA, NICER, and Swift observations during the decay phase of the January 2019 outburst. In millimeter wavelengths, radio continuum emissions in the frequency range of 89.56–351.44 GHz are measured. We found that the flux densities at millimeter wavelength varied between 12.18 mJy and 18.47 mJy with spectral index ((alpha )) of (0.28pm 0.02). The broadband spectrum suggests that the source was accompanied by weak synchrotron emission from the compact jets. Broadband spectral study indicates that MAXI J1348–630 falls in the regime of “radio-quiet” during the decay phase of the outburst. The NICER spectrum is fitted by a combined model of disk blackbody component (diskbb) along with a comptonization component (simpl) which explains the power-law continuum caused by the thermal Comptonisation of soft disk photons in a hot gas of electrons. The NICER spectrum is dominated by the comptonised components during the decay phase of the outburst close to the hard state of the source. We have investigated the correlation between X-ray and radio luminosity using quasi-simultaneous ALMA and NICER data to understand the source nature by locating the source in the (L_{X})-(L_{R}) diagram. The correlation study of radio/X-ray luminosity suggests that MAXI J1348–630 did not follow the well-known track for black holes and it is a new member of a restricted group of sources.</div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"369 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139690264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}

引用次数: 0

Dark energy constraints from Pantheon+ Ia supernovae data 来自 Pantheon+ Ia 超新星数据的暗能量约束

IF 1.8 4区物理与天体物理

Astrophysics and Space Science Pub Date : 2024-02-02 DOI: 10.1007/s10509-024-04282-x

Sergio Torres-Arzayus

{"title":"Dark energy constraints from Pantheon+ Ia supernovae data","authors":"Sergio Torres-Arzayus","doi":"10.1007/s10509-024-04282-x","DOIUrl":"10.1007/s10509-024-04282-x","url":null,"abstract":"<div>Measurements of the current expansion rate of the Universe, (H_{0}), using standard candles, disagree with those derived from observations of the Cosmic Microwave Background (CMB). This discrepancy, known as the Hubble tension, is substantial and suggests the possibility of revisions to the standard cosmological model (Cosmological constant (Lambda ) and cold dark matter – (Lambda CDM)). Dynamic dark energy (DE) models that introduce deviations in the expansion history relative to (Lambda CDM) could potentially explain this tension. We used Type Ia supernovae (SNe) data to test a dynamic DE model consisting of an equation of state that varies linearly with the cosmological scale factor (a). To evaluate this model, we developed a new statistic (the (T_{alpha }) statistic) used in conjunction with an optimization code that minimizes its value to obtain model parameters. The (T_{alpha }) statistic reduces bias errors (in comparison to the (chi ^{2}) statistic) because it retains the sign of the residuals, which is meaningful in testing the dynamic DE model as the deviations in the expansion history introduced by this model act asymmetrically in redshift space. The DE model fits the SNe data reasonably well, but the available SNe data lacks the statistical power to discriminate between (Lambda CDM) and alternative models. To further assess the model using CMB data, we computed the distance to the last scattering surface and compared the results with that derived from the Planck observations. Although the simple dynamic DE model tested does not completely resolve the tension, it is not ruled out by the data and could still play a role alongside other physical effects.</div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":"369 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139661789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}

引用次数: 0