Journal of Astrophysics and Astronomy最新文献_第5页

Investigating polarization characteristics of GRB 200503A and GRB 201009A 研究GRB 200503A和GRB 201009A的偏振特性

IF 1.6 4区物理与天体物理

Journal of Astrophysics and Astronomy Pub Date : 2025-06-27 DOI: 10.1007/s12036-025-10071-x

Divita Saraogi, Suman Bala, Jitendra Joshi, Shabnam Iyyani, Varun Bhalerao, J. Venkata Aditya, D. S. Svinkin, A. Tsvetkova, D. D. Frederiks, A. L. Lysenko, A. V. Ridnaia, A. S. Kozyrev, D. V. Golovin, I. G. Mitrofanov, M. L. Litvak, A. B. Sanin, Tanmoy Chattopadyay, Soumya Gupta, Gaurav Waratkar, Dipankar Bhattacharya, Santosh Vadawale, Gulab Dewangan

引用次数: 0

Variation in horizontal component of geomagnetic field during the April 2023 space weather event over ({pm }75^circ ) longitude sectors: Insights 2023年4月空间天气事件期间({pm }75^circ )经度扇区地磁场水平分量的变化：洞见

IF 1.6 4区物理与天体物理

Journal of Astrophysics and Astronomy Pub Date : 2025-06-27 DOI: 10.1007/s12036-025-10066-8

S. S. Rao, Nandita Srivastava, D. Chakrabarty

{"title":"Variation in horizontal component of geomagnetic field during the April 2023 space weather event over ({pm }75^circ ) longitude sectors: Insights","authors":"S. S. Rao, Nandita Srivastava, D. Chakrabarty","doi":"10.1007/s12036-025-10066-8","DOIUrl":"10.1007/s12036-025-10066-8","url":null,"abstract":"<div>This study investigates the response of the horizontal component of the geomagnetic field (H) during the geomagnetic storm of 23–24 April 2023, which was triggered by an Interplanetary Coronal Mass Ejection (ICME). This storm provides a unique opportunity to evaluate the responses in H corresponding to the passage of shock, sheath, and magnetic cloud (MC) structures associated with the ICME. To fulfill this objective, the latitudinal profiles of H-variation are presented for the two distinct cases of the Indian ((75^circ )E) and American ((75^circ )W) sectors. It is found that: (i) latitudinal variances in the phase, amplitude and modulations of H-variation are significant, with amplitude decreasing from mid- to low-latitude, (ii) even though the two longitude sectors had distinct local times throughout the passage of the ICME structures (shock, sheath, and MC), significant storm-induced H-variations of ionospheric/magnetospheric origin are seen, and (iii) H-variation during the passage of sheath and MC region are anomalous, particularly over the Indian longitude sector. The observations showed a reduction of amplitude 350 nT (20:00 UT, April 23) in H-variation at mid-latitude station NVS in the Indian sector during the passage of the CME sheath compared to a reduction of an amplitude of 125 nT (02:45 UT, April 24) during the passage of the MC. These aspects are discussed, and important insights on the response of the terrestrial H-component corresponding to the arrival of different structures in ICME are presented.</div>","PeriodicalId":610,"journal":{"name":"Journal of Astrophysics and Astronomy","volume":"46 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145169752","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

Sample of 25 radio galaxies with highly unusual radio morphologies, selected from the LoTSS-DR2 survey at 144 MHz 从144mhz的LoTSS-DR2调查中选择的25个具有非常不寻常的无线电形态的射电星系样本

IF 1.6 4区物理与天体物理

Journal of Astrophysics and Astronomy Pub Date : 2025-06-26 DOI: 10.1007/s12036-025-10059-7

Gopal-Krishna, Dusmanta Patra, Ravi Joshi

引用次数: 0

Preliminary cosmological analysis of stellar population synthesis of galaxies released by LAMOST LRS DR11 LAMOST LRS DR11发布的星系恒星族合成的初步宇宙学分析

IF 1.6 4区物理与天体物理

Journal of Astrophysics and Astronomy Pub Date : 2025-06-25 DOI: 10.1007/s12036-025-10070-y

Y. H. Chen

{"title":"Preliminary cosmological analysis of stellar population synthesis of galaxies released by LAMOST LRS DR11","authors":"Y. H. Chen","doi":"10.1007/s12036-025-10070-y","DOIUrl":"10.1007/s12036-025-10070-y","url":null,"abstract":"<div>The evolution of the Universe together with galaxies, is one of the fundamental issues that we humans are most interested in. Both the observations of tidal streams from SDSS and the theory of (Lambda )CDM support the hierarchical merging theory. The study of high redshift celestial bodies contributes to a more in-depth study of cosmology. The LAMOST low-resolution search catalog DR11 v1.0 has released 11,939,296 spectra, including 11,581,542 stars, 275,302 galaxies and 82,452 quasars, and so on. The data of 28,780 stellar population synthesis of galaxies and some high redshift quasars are used to do a preliminary statistical research. We selected the data with small errors for analysis and obtained some basic statistical conclusions. Older galaxies have relatively larger stellar velocity dispersions. The larger the metallicity, the greater the stellar velocity dispersion. These statistical results are reasonable and consistent with previous work. Because the stellar velocity dispersion is driven by the total mass of a galaxy at the first order and more massive galaxies have older ages and greater metallicities. The spectra of high redshift quasars show clear Gunn–Peterson trough and Lyman-(alpha ) forest. The identified emission lines and high redshift celestial spectra released by LAMOST, can be used for cosmological research.</div>","PeriodicalId":610,"journal":{"name":"Journal of Astrophysics and Astronomy","volume":"46 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145168517","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

Solar system research prospects for the decade and beyond 未来十年及以后的太阳系研究前景

IF 1.6 4区物理与天体物理

Journal of Astrophysics and Astronomy Pub Date : 2025-06-23 DOI: 10.1007/s12036-025-10060-0

Shyama Narendranath, Shashikiran Ganesh, Dipen Sahu, Ritesh Kumar Mishra, Megha Bhatt, Sumanta Sarkhel, Guneshwar Thangjam, Kuljeet Kaur Marhas, K. Aravind, Kumar Venkataramani, Prithish Halder, Prachi Prajapati, Parmeswaran Sreekumar

{"title":"Solar system research prospects for the decade and beyond","authors":"Shyama Narendranath, Shashikiran Ganesh, Dipen Sahu, Ritesh Kumar Mishra, Megha Bhatt, Sumanta Sarkhel, Guneshwar Thangjam, Kuljeet Kaur Marhas, K. Aravind, Kumar Venkataramani, Prithish Halder, Prachi Prajapati, Parmeswaran Sreekumar","doi":"10.1007/s12036-025-10060-0","DOIUrl":"10.1007/s12036-025-10060-0","url":null,"abstract":"<div>Our solar system, consisting of the Sun, planets, Moons, asteroids, and comets, along with gas, dust, ice, and radiation, is a very complex and dynamic system. Globally, planetary, astronomy, and small-body exploration programs have made great strides in understanding the formation and evolution of stellar systems while also providing detailed views of individual bodies. The forthcoming decades offer immense opportunities for planetary exploration from space and observations from ground telescopes that portend to very significantly expand not only the horizons of human exploration but also provide a more fundamental understanding of the evolutionary pathways that led to the myriad diversity in our Solar System. The past, present, and future of the solar system also serve as a Rosetta stone to decipher the physics, chemistry, and biology of the exo-planetary systems. Here, we recommend solar system exploration objectives for the decade and beyond in the context of current global developments in the field and research groups in India.\u0000</div>","PeriodicalId":610,"journal":{"name":"Journal of Astrophysics and Astronomy","volume":"46 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145168813","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

On the origin of transient features in cosmological N-Body simulations 论宇宙n体模拟中瞬态特征的起源

IF 1.6 4区物理与天体物理

Journal of Astrophysics and Astronomy Pub Date : 2025-06-16 DOI: 10.1007/s12036-025-10055-x

J. S. Bagla, Swati Gavas

{"title":"On the origin of transient features in cosmological N-Body simulations","authors":"J. S. Bagla, Swati Gavas","doi":"10.1007/s12036-025-10055-x","DOIUrl":"10.1007/s12036-025-10055-x","url":null,"abstract":"<div>We study the effect of gravitational clustering at small scales on larger scales by studying mode coupling between virialized halos. We build on the calculation by Peebles (1974), where it was shown that a virialized halo does not contribute any mode coupling terms at small wave numbers k. Using a perturbative expansion in wave number, we show that this effect is small and arises from the deviation of halo shapes from spherical and also on tidal interactions between halos. We connect this with the impact of finite mass resolution of cosmological N-Body simulations on the evolution of perturbations at early times. This difference between the expected evolution and the evolution obtained in cosmological N-Body simulations can be quantified using such an estimate. We also explore the impact of a finite shortest scale up to which the desired power spectrum is realized in simulations. Several simulation studies have shown that this effect is small compared to the effect of perturbations at large scales on smaller scales. It is nevertheless important to study these effects and develop a general approach for estimating their magnitude. This is especially relevant in the present era of precision cosmology. We provide basic estimates of the magnitude of these effects and their power spectrum dependence. We find that the impact of small-scale cutoff in the initial power spectrum and discreteness increases with ((n+3)), with n being the index of the power spectrum. In general, we recommend that cosmological simulation data should be used only if the scale of non-linearity, defined as the scale where the linearly extrapolated rms amplitude of fluctuations is unity, is larger than the average inter-particle separation.</div>","PeriodicalId":610,"journal":{"name":"Journal of Astrophysics and Astronomy","volume":"46 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145165668","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

Galaxies, clusters, and intergalactic medium: A vision document for the Indian Astronomical Community 星系、星系团和星系间介质：印度天文社团的远景文件

IF 1.6 4区物理与天体物理

Journal of Astrophysics and Astronomy Pub Date : 2025-06-11 DOI: 10.1007/s12036-025-10056-w

Ruta Kale, Sowgat Muzahid, Vikram Khaire, Namrata Roy, Sanskriti Das, Hum Chand, Suchetana Chatterjee, Abhirup Datta, Mousumi Das, Ananda Hota, Chanda J. Jog, Sreeja Kartha, Dharam Vir Lal, Chayan Mondal, Biman Nath, Prakriti Pal Choudhury, Surajit Paul, Sonali Sachdeva, Prateek Sharma, Priyanka Singh, Veeresh Singh, Smitha Subramanian, Sharanya Sur

{"title":"Galaxies, clusters, and intergalactic medium: A vision document for the Indian Astronomical Community","authors":"Ruta Kale, Sowgat Muzahid, Vikram Khaire, Namrata Roy, Sanskriti Das, Hum Chand, Suchetana Chatterjee, Abhirup Datta, Mousumi Das, Ananda Hota, Chanda J. Jog, Sreeja Kartha, Dharam Vir Lal, Chayan Mondal, Biman Nath, Prakriti Pal Choudhury, Surajit Paul, Sonali Sachdeva, Prateek Sharma, Priyanka Singh, Veeresh Singh, Smitha Subramanian, Sharanya Sur","doi":"10.1007/s12036-025-10056-w","DOIUrl":"10.1007/s12036-025-10056-w","url":null,"abstract":"<div>Galaxies, clusters, and the intergalactic medium (IGM) are the essential and interconnected components of the cosmic ecosystem. Galaxies, with their diverse morphologies and stellar populations, are the building blocks of cosmic structure, harboring stars, gas, dust, cosmic rays, magnetic fields, and dark matter. Galaxy clusters, immense gravitational unions of galaxies, offer profound insights into galaxy formation, cosmology, and the nature of dark matter. Bridging these cosmic islands is the IGM, a vast expanse of primordial gas enriched with traces of heavy elements. It harbors the majority of cosmic baryons distributed within an intricate network of filaments and voids. Together, galaxies, clusters, and the IGM offer a holistic view of the cosmic architecture, each playing a unique role in shaping the universe’s grand design. Indian scientists have made substantial contributions to research on galaxies, clusters, and the IGM, both theoretical and observational. To pursue and advance such contributions at par with the international level, the astronomical community emphasizes the urgent requirement for access to cutting-edge ground-based and space-based observatories and computing facilities. Access to state-of-the-art observational and computing facilities will sustain ongoing endeavors and enable Indian scientists to remain at the forefront of advancements in these fields, fostering continued relevance and innovation in astronomy research.</div>","PeriodicalId":610,"journal":{"name":"Journal of Astrophysics and Astronomy","volume":"46 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145163818","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

Self-triggering approach of cosmic ray radio emission at Semnan University radio array experiment 塞姆南大学射电阵列实验中宇宙射线射电发射的自触发方法

IF 1.6 4区物理与天体物理

Journal of Astrophysics and Astronomy Pub Date : 2025-06-10 DOI: 10.1007/s12036-025-10062-y

M. MOSTAFAVI ALHOSSEINI, G. RASTEGARZADEH

{"title":"Self-triggering approach of cosmic ray radio emission at Semnan University radio array experiment","authors":"M. MOSTAFAVI ALHOSSEINI, G. RASTEGARZADEH","doi":"10.1007/s12036-025-10062-y","DOIUrl":"10.1007/s12036-025-10062-y","url":null,"abstract":"<div>Radio detection of cosmic rays investigates the electromagnetic component of extensive air showers. It is possible to obtain the most critical properties of a cosmic ray, including the depth of shower maximum, energy, and type of primary particle, from radio measurements. Semnan University Radio Array is a new experiment that strives to detect radio emissions from extensive air showers induced by ultra-high energy cosmic rays. To fully harness the potential of the radio detection method in a self-trigger setup, it is essential to have artificial digital and analog filters to eliminate major unwanted emissions, analog-to-digital converters with appropriate specifications for accurate signal reconstruction, and data processing units capable of implementing software-based analysis alongside advanced digital signal processing techniques. This paper describes the design and implementation of a self-triggering approach in SURA-4 as the first phase of the SURA experiment to preserve cosmic ray candidates while removing unwanted emissions by utilizing the capabilities of analog and digital elements and incorporating a custom software framework for radio signal analyses. The ultimate validation of this approach for reliably distinguishing cosmic rays from anthropogenic radio frequency interferences will be pursued in future experiment phases, including cross-verification with three particle detectors.</div>","PeriodicalId":610,"journal":{"name":"Journal of Astrophysics and Astronomy","volume":"46 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145163668","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

Re-evaluation of ALMA detection of circumstellar (hbox {PH}_3) in the AGB envelope IRC(+)10216: Evidence for misidentification with HCN 对AGB包膜IRC (+) 10216中星周(hbox {PH}_3)的ALMA检测的再评价：与HCN误认的证据

IF 1.6 4区物理与天体物理

Journal of Astrophysics and Astronomy Pub Date : 2025-05-31 DOI: 10.1007/s12036-025-10058-8

M. Agúndez, L. Velilla-Prieto, J. P. Fonfría, J. Cernicharo

{"title":"Re-evaluation of ALMA detection of circumstellar (hbox {PH}_3) in the AGB envelope IRC(+)10216: Evidence for misidentification with HCN","authors":"M. Agúndez, L. Velilla-Prieto, J. P. Fonfría, J. Cernicharo","doi":"10.1007/s12036-025-10058-8","DOIUrl":"10.1007/s12036-025-10058-8","url":null,"abstract":"<div>The article ‘Confirmation of interstellar phosphine towards asymptotic giant branch star IRC(+)10216’ by A. Manna and S. Pal uses ALMA data of the C-star envelope IRC(+)10216 to claim a confirmation of the detection of (hbox {PH}_3) in this source. The article, however, incorrectly assigns an emission feature observed in the ALMA spectrum of IRC(+)10216 to (hbox {PH}_3), while we find that it arises from a highly vibrationally excited state of HCN. Concretely the feature can be confidently assigned to the (J=3)–2, (ell =0) transition of HCN in the (nu _1 + 4nu _2) vibrational state based on the observation of the (ell = +2) and (ell = -2) components of the same rotational transition, (J=3)–2, with the observed relative intensities in agreement with the relative line strengths. The detection of (hbox {PH}_3) in IRC(+)10216 remains confirmed based on the observation of the (J=1)–0 and (J=2)–1 lines with the single-dish telescopes IRAM 30m, ARO SMT 10m, and Herschel (Agúndez et al. 2008, 2014; Tenenbaum & Ziurys 2008).\u0000</div>","PeriodicalId":610,"journal":{"name":"Journal of Astrophysics and Astronomy","volume":"46 1","pages":""},"PeriodicalIF":1.6,"publicationDate":"2025-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145171063","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

Investigating the timing and spectral signatures of Be/X-ray pulsar RX J0520.5−6932 during its 2024 outburst using NuSTAR 利用NuSTAR研究了Be/ x射线脉冲星RX J0520.5−6932在2024年爆发期间的时间和光谱特征

IF 1.1 4区物理与天体物理

Journal of Astrophysics and Astronomy Pub Date : 2025-05-21 DOI: 10.1007/s12036-025-10057-9

Chetana Jain

{"title":"Investigating the timing and spectral signatures of Be/X-ray pulsar RX J0520.5−6932 during its 2024 outburst using NuSTAR","authors":"Chetana Jain","doi":"10.1007/s12036-025-10057-9","DOIUrl":"10.1007/s12036-025-10057-9","url":null,"abstract":"<div>The Be X-ray binary pulsar RX J0520.5(-)6932 in the Large Magellanic Cloud recently underwent an outburst after a gap of about 10 years. This paper presents the timing and spectral analysis of this transient system using the NuSTAR observation that was made near the peak of the outburst. Coherent pulsations were detected with a period of 8.029877(9) s (at MJD 60412.87) up to 50 keV. The pulse profile was single-peaked and asymmetric, with the presence of two local minima on the slowly rising edge up to about 18 keV. The hard X-ray pulse profiles were relatively smooth. The 3–50 keV FPMA–FPMB energy spectrum was well described by a thermally comptonized continuum with an electron temperature of (sim )5.3 keV and a photon index of (sim )1.36. A broad (sim )6.32 keV Fe emission line and a cyclotron resonant scattering feature (CRSF) with (sim )32.3 keV central energy, corresponding to a surface magnetic field strength of (sim ) (2.8times 10^{12}) G were also required to describe the energy spectrum. The pulse phase resolved spectroscopy indicated significant variation in energy and width of the CRSF and iron emission line. A (sim )14.6 keV absorption feature was also detected at specific pulse phases.</div>","PeriodicalId":610,"journal":{"name":"Journal of Astrophysics and Astronomy","volume":"46 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2025-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144100334","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