Pub Date : 2025-09-02DOI: 10.1016/j.newast.2025.102468
Marcel Nogueira de Oliveira , Carlos E. Navia , Andre Asevedo Nepomuceno
We investigate the physical mechanisms responsible for the solar energetic particle (SEP) event observed on 1 November 2014, during which several ground-based detectors in both hemispheres, specifically those located on the sunlit western side of Earth, recorded simultaneous enhancements in counting rates. The event is attributed to Active Region (AR) 2192, one of the most active sunspot groups of Solar Cycle 24, which at the time was situated near the western limb of the solar disk, approaching the far side of the Sun. A plausible scenario involves a combination of solar eruptive activity, particle acceleration by a shock wave driven by a coronal mass ejection (CME), and the presence of a heliospheric current sheet (HCS) sector crossing, which may have enhanced magnetic connectivity between the Sun and Earth. We emphasize data from the New-Tupi muon detector, operating in scaler mode and located near the central region of the South Atlantic Anomaly (SAA). The particle excess detected on 1 November 2014 by ground-based instruments spanning different rigidity regimes, in conjunction with satellite observations, indicates that the signal was not a localized phenomenon. Assuming a power-law energy spectrum for the SEP population, we find that its high-energy tail in the GeV range is consistent with proton flux measurements reported by GOES-13. We present and discuss the details of these observations.
{"title":"Solar energetic particle transport via the heliospheric current sheet: Evidence of a ground-level response on All Saints Day, 2014","authors":"Marcel Nogueira de Oliveira , Carlos E. Navia , Andre Asevedo Nepomuceno","doi":"10.1016/j.newast.2025.102468","DOIUrl":"10.1016/j.newast.2025.102468","url":null,"abstract":"<div><div>We investigate the physical mechanisms responsible for the solar energetic particle (SEP) event observed on 1 November 2014, during which several ground-based detectors in both hemispheres, specifically those located on the sunlit western side of Earth, recorded simultaneous enhancements in counting rates. The event is attributed to Active Region (AR) 2192, one of the most active sunspot groups of Solar Cycle 24, which at the time was situated near the western limb of the solar disk, approaching the far side of the Sun. A plausible scenario involves a combination of solar eruptive activity, particle acceleration by a shock wave driven by a coronal mass ejection (CME), and the presence of a heliospheric current sheet (HCS) sector crossing, which may have enhanced magnetic connectivity between the Sun and Earth. We emphasize data from the New-Tupi muon detector, operating in scaler mode and located near the central region of the South Atlantic Anomaly (SAA). The particle excess detected on 1 November 2014 by ground-based instruments spanning different rigidity regimes, in conjunction with satellite observations, indicates that the signal was not a localized phenomenon. Assuming a power-law energy spectrum for the SEP population, we find that its high-energy tail in the GeV range is consistent with proton flux measurements reported by GOES-13. We present and discuss the details of these observations.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"122 ","pages":"Article 102468"},"PeriodicalIF":2.1,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144934278","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}
Pub Date : 2025-08-29DOI: 10.1016/j.newast.2025.102466
Sreevarsha Sreejith , Maria V. Pruzhinskaya , Alina A. Volnova , Vadim V. Krushinsky , Konstantin L. Malanchev , Emille E.O. Ishida , Anastasia D. Lavrukhina , Timofey A. Semenikhin , Emmanuel Gangler , Matwey V. Kornilov , Vladimir S. Korolev
Accurate photometry in astronomical surveys is challenged by image artefacts, which affect measurements and degrade data quality. Due to the large amount of available data, this task is increasingly handled using machine learning algorithms, which often require a labelled training set to learn data patterns. We present an expert-labelled dataset of 1127 artefacts with 1213 labels from 26 fields in ZTF DR3, along with a complementary set of nominal objects. The artefact dataset was compiled using the active anomaly detection algorithm PineForest, developed by the SNAD team. These datasets can serve as valuable resources for real-bogus classification, catalogue cleaning, anomaly detection, and educational purposes. Both artefacts and nominal images are provided in FITS format in two sizes (28 × 28 and 63 × 63 pixels). The datasets are publicly available for further scientific applications.
{"title":"Dataset of artefacts for machine learning applications in astronomy","authors":"Sreevarsha Sreejith , Maria V. Pruzhinskaya , Alina A. Volnova , Vadim V. Krushinsky , Konstantin L. Malanchev , Emille E.O. Ishida , Anastasia D. Lavrukhina , Timofey A. Semenikhin , Emmanuel Gangler , Matwey V. Kornilov , Vladimir S. Korolev","doi":"10.1016/j.newast.2025.102466","DOIUrl":"10.1016/j.newast.2025.102466","url":null,"abstract":"<div><div>Accurate photometry in astronomical surveys is challenged by image artefacts, which affect measurements and degrade data quality. Due to the large amount of available data, this task is increasingly handled using machine learning algorithms, which often require a labelled training set to learn data patterns. We present an expert-labelled dataset of 1127 artefacts with 1213 labels from 26 fields in ZTF DR3, along with a complementary set of nominal objects. The artefact dataset was compiled using the active anomaly detection algorithm <span>PineForest</span>, developed by the SNAD team. These datasets can serve as valuable resources for real-bogus classification, catalogue cleaning, anomaly detection, and educational purposes. Both artefacts and nominal images are provided in FITS format in two sizes (28 × 28 and 63 × 63 pixels). The datasets are publicly available for further scientific applications.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"122 ","pages":"Article 102466"},"PeriodicalIF":2.1,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145020441","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}
Pub Date : 2025-08-25DOI: 10.1016/j.newast.2025.102465
Arijit Manna, Sabyasachi Pal
Ethylene oxide (c- ) and its isomer, acetaldehyde (CH3CHO), are important complex organic molecules owing to their potential role in the formation of amino acids (R–CH(NH2)-COOH) in interstellar medium. The detection of c- in hot molecular cores suggests the possible existence of larger ring-shaped molecules containing more than three carbon atoms, such as furan (c- ), which shares structural similarities with ribose (C5H10O5), the sugar component of DNA. In this study, we report the first detection of the rotational emission lines of c- and CH3CHO towards the hot molecular core G358.93–0.03 MM1, based on observations from the Atacama Large Millimeter/Submillimeter Array (ALMA) in band 7. The fractional abundances of c- and CH3CHO relative to H2 are and , respectively. The column density ratio between CH3CHO and c- is . A Pearson correlation heat map reveals strong positive correlations ( 0.5) between the abundances and excitation temperatures of c- and CH3CHO, suggesting a possible chemical connection between those two molecules. To investigate this further, we conducted a two-phase warm-up chemical model using the gas-grain chemical code UCLCHEM. A comparison between our derived abundances and the predictions from our chemical model and existence model demonstrates good agreement within factors of 0.73 and 0.74, respectively. We propose that c- may form in G358.93–0.03 MM1 via the grain surface reaction between C2H4 and O, but CH3CHO may be produced through the surface reaction between CH3 and HCO.
{"title":"First detection of ethylene oxide and acetaldehyde in hot core G358.93–0.03 MM1: Tracing prebiotic oxygen chemistry","authors":"Arijit Manna, Sabyasachi Pal","doi":"10.1016/j.newast.2025.102465","DOIUrl":"10.1016/j.newast.2025.102465","url":null,"abstract":"<div><div>Ethylene oxide (c- <figure><img></figure> ) and its isomer, acetaldehyde (CH<sub>3</sub>CHO), are important complex organic molecules owing to their potential role in the formation of amino acids (R–CH(NH<sub>2</sub>)-COOH) in interstellar medium. The detection of c- <figure><img></figure> in hot molecular cores suggests the possible existence of larger ring-shaped molecules containing more than three carbon atoms, such as furan (c- <figure><img></figure> ), which shares structural similarities with ribose (C<sub>5</sub>H<sub>10</sub>O<sub>5</sub>), the sugar component of DNA. In this study, we report the first detection of the rotational emission lines of c- <figure><img></figure> and CH<sub>3</sub>CHO towards the hot molecular core G358.93–0.03 MM1, based on observations from the Atacama Large Millimeter/Submillimeter Array (ALMA) in band 7. The fractional abundances of c- <figure><img></figure> and CH<sub>3</sub>CHO relative to H<sub>2</sub> are <span><math><mrow><mrow><mo>(</mo><mn>2</mn><mo>.</mo><mn>1</mn><mo>±</mo><mn>0</mn><mo>.</mo><mn>2</mn><mo>)</mo></mrow><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>9</mn></mrow></msup></mrow></math></span> and <span><math><mrow><mrow><mo>(</mo><mn>7</mn><mo>.</mo><mn>1</mn><mo>±</mo><mn>0</mn><mo>.</mo><mn>9</mn><mo>)</mo></mrow><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>9</mn></mrow></msup></mrow></math></span>, respectively. The column density ratio between CH<sub>3</sub>CHO and c- <figure><img></figure> is <span><math><mrow><mn>3</mn><mo>.</mo><mn>4</mn><mo>±</mo><mn>0</mn><mo>.</mo><mn>7</mn></mrow></math></span>. A Pearson correlation heat map reveals strong positive correlations (<span><math><mi>r</mi></math></span> <span><math><mo>></mo></math></span> 0.5) between the abundances and excitation temperatures of c- <figure><img></figure> and CH<sub>3</sub>CHO, suggesting a possible chemical connection between those two molecules. To investigate this further, we conducted a two-phase warm-up chemical model using the gas-grain chemical code UCLCHEM. A comparison between our derived abundances and the predictions from our chemical model and existence model demonstrates good agreement within factors of 0.73 and 0.74, respectively. We propose that c- <figure><img></figure> may form in G358.93–0.03 MM1 via the grain surface reaction between C<sub>2</sub>H<sub>4</sub> and O, but CH<sub>3</sub>CHO may be produced through the surface reaction between CH<sub>3</sub> and HCO.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"122 ","pages":"Article 102465"},"PeriodicalIF":2.1,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144934279","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}
Pub Date : 2025-08-20DOI: 10.1016/j.newast.2025.102464
Kangujam Priyokumar Singh, Asem Jotin Meitei
In this work, we examine a five-dimensional anisotropic Bianchi type III cosmological model within the framework of Lyra geometry. We investigate the matter bounce scenario under the dark energy condition for the equation of state relationship with . Utilizing the energy–momentum tensor of a perfect fluid, we derive the solution for the model universe. Our proposed model also evaluates the behavior of energy conditions, state-finders, the current value of the deceleration parameter and stability conditions.
{"title":"Non-singular bounce scenario of Higher dimensional dark energy cosmological model in Lyra geometry","authors":"Kangujam Priyokumar Singh, Asem Jotin Meitei","doi":"10.1016/j.newast.2025.102464","DOIUrl":"10.1016/j.newast.2025.102464","url":null,"abstract":"<div><div>In this work, we examine a five-dimensional anisotropic Bianchi type III cosmological model within the framework of Lyra geometry. We investigate the matter bounce scenario under the dark energy condition for the equation of state relationship <span><math><mrow><mi>ρ</mi><mo>=</mo><mi>W</mi><mi>p</mi></mrow></math></span> with <span><math><mrow><mi>W</mi><mo>=</mo><mo>−</mo><mn>1</mn></mrow></math></span>. Utilizing the energy–momentum tensor of a perfect fluid, we derive the solution for the model universe. Our proposed model also evaluates the behavior of energy conditions, state-finders, the current value of the deceleration parameter and stability conditions.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"121 ","pages":"Article 102464"},"PeriodicalIF":2.1,"publicationDate":"2025-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144886243","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}
Pub Date : 2025-08-20DOI: 10.1016/j.newast.2025.102462
Mithun Bairagi
We investigate the late-time cosmic acceleration within the framework of generalized Einstein-Aether gravity incorporating cubic curvature corrections. Employing three widely used dynamical dark energy parametrizations-CPL, JBP, and BA, we reconstruct the cosmic expansion history by constraining the free model parameters using Type Ia Supernova (SN Ia) data from the Pantheon compilations via a -minimization approach. We determine best-fit values for the model parameters and evaluate key cosmological quantities such as the dark energy density ,the matter density , the Hubble constant , and the deceleration parameter of the present universe. We also examine the evolution of the potential and the kinetic energy of the equivalent scalar field representing dark energy as functions of redshift .
{"title":"Dark energy parametrizations in Einstein–Aether gravity with cubic curvature corrections","authors":"Mithun Bairagi","doi":"10.1016/j.newast.2025.102462","DOIUrl":"10.1016/j.newast.2025.102462","url":null,"abstract":"<div><div>We investigate the late-time cosmic acceleration within the framework of generalized Einstein-Aether gravity incorporating cubic curvature corrections. Employing three widely used dynamical dark energy parametrizations-CPL, JBP, and BA, we reconstruct the cosmic expansion history by constraining the free model parameters using Type Ia Supernova (SN Ia) data from the Pantheon compilations via a <span><math><msup><mrow><mi>χ</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span>-minimization approach. We determine best-fit values for the model parameters and evaluate key cosmological quantities such as the dark energy density <span><math><msub><mrow><mi>Ω</mi></mrow><mrow><msub><mrow><mtext>de</mtext></mrow><mrow><mn>0</mn></mrow></msub></mrow></msub></math></span>,the matter density <span><math><msub><mrow><mi>Ω</mi></mrow><mrow><msub><mrow><mtext>m</mtext></mrow><mrow><mn>0</mn></mrow></msub></mrow></msub></math></span>, the Hubble constant <span><math><msub><mrow><mi>H</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span>, and the deceleration parameter <span><math><msub><mrow><mi>q</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span> of the present universe. We also examine the evolution of the potential <span><math><mrow><mi>V</mi><mrow><mo>(</mo><mi>z</mi><mo>)</mo></mrow></mrow></math></span> and the kinetic energy <span><math><mfrac><mrow><msup><mrow><mover><mrow><mi>ϕ</mi></mrow><mrow><mo>̇</mo></mrow></mover></mrow><mrow><mn>2</mn></mrow></msup></mrow><mrow><mn>2</mn></mrow></mfrac></math></span> of the equivalent scalar field representing dark energy as functions of redshift <span><math><mi>z</mi></math></span>.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"121 ","pages":"Article 102462"},"PeriodicalIF":2.1,"publicationDate":"2025-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144895110","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}
Pub Date : 2025-08-11DOI: 10.1016/j.newast.2025.102463
Athar A. Dar , Zahir Shah , Sunder Sahayanathan , Naseer Iqbal , Subir Bhattacharyya , Debanjan Bose
The Flat Spectrum Radio Quasar (FSRQ) B2 1308+326 was in its highest -ray flaring state during 60260-60310 MJD. During this period, the source was detected in very high energy (VHE) by the large-sized telescope (LST-1). We conducted a detailed broadband spectral study of this source using the simultaneous data available in optical/UV, X-ray, and -ray bands. For the broadband spectral study, we select two gamma-ray high-flux states (59750-59800 MJD, 60260-60310 MJD) and one low-flux state (59250-59320 MJD). The broadband spectral energy distribution (SED) during these flux states are studied under leptonic emission scenario involving synchrotron, synchrotron self Compton (SSC) and external Compton (EC) processes. During the epochs, 59750-59800 MJD (high-flux state) and 59250-59320 MJD (low-flux state), the broadband SED is well fitted under the leptonic emission model while satisfying the equipartition between the particle and the magnetic field energy densities. However, the flaring state (60260-60310 MJD), during which the source showed VHE emission, demands deviation from equipartition by a factor of for the successful reproduction of the SED. This suggests the system may be under non-equilibrium condition or alternatively additional emission components may be active.
{"title":"Unraveling the broadband spectrum of B2 1308+326: A clue to its high energy emission mechanism","authors":"Athar A. Dar , Zahir Shah , Sunder Sahayanathan , Naseer Iqbal , Subir Bhattacharyya , Debanjan Bose","doi":"10.1016/j.newast.2025.102463","DOIUrl":"10.1016/j.newast.2025.102463","url":null,"abstract":"<div><div>The Flat Spectrum Radio Quasar (FSRQ) B2 1308+326 was in its highest <span><math><mi>γ</mi></math></span>-ray flaring state during 60260-60310 MJD. During this period, the source was detected in very high energy (VHE) by the large-sized telescope (LST-1). We conducted a detailed broadband spectral study of this source using the simultaneous data available in optical/UV, X-ray, and <span><math><mi>γ</mi></math></span>-ray bands. For the broadband spectral study, we select two gamma-ray high-flux states (59750-59800 MJD, 60260-60310 MJD) and one low-flux state (59250-59320 MJD). The broadband spectral energy distribution (SED) during these flux states are studied under leptonic emission scenario involving synchrotron, synchrotron self Compton (SSC) and external Compton (EC) processes. During the epochs, 59750-59800 MJD (high-flux state) and 59250-59320 MJD (low-flux state), the broadband SED is well fitted under the leptonic emission model while satisfying the equipartition between the particle and the magnetic field energy densities. However, the flaring state (60260-60310 MJD), during which the source showed VHE emission, demands deviation from equipartition by a factor of <span><math><mrow><mo>∼</mo><mn>14</mn></mrow></math></span> for the successful reproduction of the SED. This suggests the system may be under non-equilibrium condition or alternatively additional emission components may be active.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"121 ","pages":"Article 102463"},"PeriodicalIF":2.1,"publicationDate":"2025-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144830950","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}
Pub Date : 2025-08-09DOI: 10.1016/j.newast.2025.102459
Hans C.G. Larsen , Casper C. Pedersen , Thomas M. Tauris , Ali Sepas , Claudia Larsen , Christophe A.N. Biscio
The origin of binary black hole (BH) mergers remains a topic of active debate, with effective spins () measured by the LIGO-Virgo-KAGRA (LVK) Collaboration providing crucial insights. In this study, our objective is to investigate the empirical distribution (and constrain individual spin components) of binary BH mergers and compare them with extensive simulations, assuming that they originate purely from isolated binaries or a mixture of formation channels. We explore scenarios using BH kicks with and without the effect of spin-axis tossing during BH formation. We employ simple yet robust Monte Carlo simulations of the final core collapse forming the second-born BH, using minimal assumptions to ensure transparency and reproducibility. The synthetic distribution is compared to the empirical data from LVK science runs O1–O3 using functional data analysis, kernel density estimations, and three different statistical tests, accounting for data uncertainties. We find strong indications for spin-axis tossing during BH formation if LVK sources are dominated by the isolated binary channel. Simulations with spin-axis tossing achieve high p-values (up to 0.882) using Kolmogorov–Smirnov, Cramer-von Mises, and Anderson–Darling tests, while without tossing, all p-values drop below 0.001 for isolated binaries. A statistically acceptable solution without tossing, however, emerges if of detected binary BH mergers result from dynamical interactions causing random BH spin directions. Finally, for an isolated binary origin, we find a preference for mass reversal in of the progenitor binaries. Predictions from this study can be tested with LVK O4+O5 data as well as the 3G detectors, Einstein Telescope and Cosmic Explorer, enabling improved constraints on formation channel ratios and the critical question of BH spin-axis tossing.
{"title":"Analysis and simulations of binary black hole merger spins — The question of spin-axis tossing at black hole formation","authors":"Hans C.G. Larsen , Casper C. Pedersen , Thomas M. Tauris , Ali Sepas , Claudia Larsen , Christophe A.N. Biscio","doi":"10.1016/j.newast.2025.102459","DOIUrl":"10.1016/j.newast.2025.102459","url":null,"abstract":"<div><div>The origin of binary black hole (BH) mergers remains a topic of active debate, with effective spins (<span><math><msub><mrow><mi>χ</mi></mrow><mrow><mi>eff</mi></mrow></msub></math></span>) measured by the LIGO-Virgo-KAGRA (LVK) Collaboration providing crucial insights. In this study, our objective is to investigate the empirical <span><math><msub><mrow><mi>χ</mi></mrow><mrow><mi>eff</mi></mrow></msub></math></span> distribution (and constrain individual spin components) of binary BH mergers and compare them with extensive simulations, assuming that they originate purely from isolated binaries or a mixture of formation channels. We explore scenarios using BH kicks with and without the effect of spin-axis tossing during BH formation. We employ simple yet robust Monte Carlo simulations of the final core collapse forming the second-born BH, using minimal assumptions to ensure transparency and reproducibility. The synthetic <span><math><msub><mrow><mi>χ</mi></mrow><mrow><mi>eff</mi></mrow></msub></math></span> distribution is compared to the empirical data from LVK science runs O1–O3 using functional data analysis, kernel density estimations, and three different statistical tests, accounting for data uncertainties. We find strong indications for spin-axis tossing during BH formation if LVK sources are dominated by the isolated binary channel. Simulations with spin-axis tossing achieve high p-values (up to 0.882) using Kolmogorov–Smirnov, Cramer-von Mises, and Anderson–Darling tests, while without tossing, all p-values drop below 0.001 for isolated binaries. A statistically acceptable solution without tossing, however, emerges if <span><math><mrow><mo>∼</mo><mn>72</mn><mspace></mspace><mo>±</mo><mspace></mspace><mn>8</mn><mtext>%</mtext></mrow></math></span> of detected binary BH mergers result from dynamical interactions causing random BH spin directions. Finally, for an isolated binary origin, we find a preference for mass reversal in <span><math><mrow><mo>∼</mo><mn>30</mn><mtext>%</mtext></mrow></math></span> of the progenitor binaries. Predictions from this study can be tested with LVK O4+O5 data as well as the 3G detectors, Einstein Telescope and Cosmic Explorer, enabling improved constraints on formation channel ratios and the critical question of BH spin-axis tossing.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"121 ","pages":"Article 102459"},"PeriodicalIF":2.1,"publicationDate":"2025-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144886242","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}
Pub Date : 2025-08-05DOI: 10.1016/j.newast.2025.102460
D. Kaur , G. Hobbs , A. Zic , J.R. Dawson , J. Morgan , W. Ling , S. Camtepe , J. Pieprzyk , M.C.M. Cheung
Pulsars have traditionally been used for research into fundamental physics and astronomy. In this paper, we investigate the expanding applications of radio pulsars in societal and industrial domains beyond their conventional scientific roles. We describe emerging applications in positioning, navigation, timing and synchronization, random number generation, space weather monitoring, public engagement, antenna calibration techniques, and leveraging extensive pulsar data sets generated by large-scale observatories. Such pulsar data sets have already been used to demonstrate quantum-computing algorithms.
We evaluate the potential for compact radio receiver systems for pulsar detection by describing optimal observing bands. We show that relatively simple and compact receiver systems can detect the brightest pulsar, Vela. The equivalent of an m-diameter dish with a small bandwidth operating around 700 MHz would be able to detect many more pulsars. Such a detector would be able to localize itself to around 10 km using pulsar navigation techniques.
The space weather community requires direct measurements of the integrated electron density at a range of solar elongations. The only method to get model-independent values is through pulsar observations and we explore the possibility of measuring dispersion measures (DMs) (and rotation measures) with a range of telescopes (observing from low to mid-frequencies) as well as using a typical model to predict the variation of the DM as a function of solar radii. We review how pulsars can be used to produce random sequences and demonstrate that such sequences can be produced using the scintillation properties of pulsars as well as from pulse jitter.
{"title":"Unlocking the hidden potential of pulsar astronomy","authors":"D. Kaur , G. Hobbs , A. Zic , J.R. Dawson , J. Morgan , W. Ling , S. Camtepe , J. Pieprzyk , M.C.M. Cheung","doi":"10.1016/j.newast.2025.102460","DOIUrl":"10.1016/j.newast.2025.102460","url":null,"abstract":"<div><div>Pulsars have traditionally been used for research into fundamental physics and astronomy. In this paper, we investigate the expanding applications of radio pulsars in societal and industrial domains beyond their conventional scientific roles. We describe emerging applications in positioning, navigation, timing and synchronization, random number generation, space weather monitoring, public engagement, antenna calibration techniques, and leveraging extensive pulsar data sets generated by large-scale observatories. Such pulsar data sets have already been used to demonstrate quantum-computing algorithms.</div><div>We evaluate the potential for compact radio receiver systems for pulsar detection by describing optimal observing bands. We show that relatively simple and compact receiver systems can detect the brightest pulsar, Vela. The equivalent of an <span><math><mrow><mo>∼</mo><mn>4</mn></mrow></math></span> <!--> <!-->m-diameter dish with a small bandwidth operating around 700<!--> <!-->MHz would be able to detect many more pulsars. Such a detector would be able to localize itself to around 10<!--> <!-->km using pulsar navigation techniques.</div><div>The space weather community requires direct measurements of the integrated electron density at a range of solar elongations. The only method to get model-independent values is through pulsar observations and we explore the possibility of measuring dispersion measures (DMs) (and rotation measures) with a range of telescopes (observing from low to mid-frequencies) as well as using a typical model to predict the variation of the DM as a function of solar radii. We review how pulsars can be used to produce random sequences and demonstrate that such sequences can be produced using the scintillation properties of pulsars as well as from pulse jitter.</div></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"121 ","pages":"Article 102460"},"PeriodicalIF":2.1,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144830951","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}
Pub Date : 2025-07-25DOI: 10.1016/j.newast.2025.102454
Ramanpreet Singh , Athul C.N. , H.K. Jassal
Cosmological parameter fitting remains crucial, especially with the abundance of available data. While many parameters have been tightly constrained, discrepancies — most notably the Hubble tension — persist between measurements obtained from different observational datasets. In this paper, we re-examine the Pantheon supernova dataset to explore deviations in the distribution of distance modulus residuals from the Gaussian distribution, which is typically the underlying assumption. We do this analysis for the concordant cosmological constant model and for a variety of dynamical dark energy models. It has been shown earlier that the residuals in this dataset are better fit to a logistic distribution. We compare the residual distributions assuming both Gaussian and Logistic likelihoods on the complete dataset, as well as various subsets of the data. The results, validated through various statistical tests, demonstrate that the Logistic likelihood provides a better fit for the full dataset and lower redshift bins, while higher redshift bins fit Gaussian and Logistic likelihoods similarly. Furthermore, the findings indicate a preference for a cosmological constant model. However analysing individual surveys within the Pantheon dataset reveals inconsistencies among subsets. The level of agreement between surveys varies depending upon the underlying likelihood function.
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Pub Date : 2025-07-25DOI: 10.1016/j.newast.2025.102455
Syed Mudassir Syed Iqbal, G.U. Khapekar
<div><div>In this study, we have investigated the non-static plane symmetric space–time with perfect fluid containing cosmic string in the frame work of <span><math><mrow><mi>f</mi><mfenced><mrow><mi>Q</mi></mrow></mfenced></mrow></math></span> gravity in which the non-metricity scalar <span><math><mi>Q</mi></math></span> describes the gravitational interaction. To find exact solutions for the field equations, we assume the metric potentials relation as <span><math><mrow><msup><mrow><mi>e</mi></mrow><mrow><mi>h</mi></mrow></msup><mo>=</mo><msup><mrow><mi>s</mi></mrow><mrow><mi>m</mi></mrow></msup></mrow></math></span>, where <span><math><mrow><mi>m</mi><mo>≠</mo><mfrac><mrow><mn>1</mn></mrow><mrow><mn>2</mn></mrow></mfrac></mrow></math></span> is an arbitrary constant and the linearly varying deceleration parameter <span><math><mrow><mi>q</mi><mfenced><mrow><mi>t</mi></mrow></mfenced><mo>=</mo><mo>−</mo><mi>k</mi><mi>t</mi><mo>+</mo><mi>n</mi><mo>−</mo><mn>1</mn></mrow></math></span>, where <span><math><mrow><mi>k</mi><mo>≥</mo><mn>0</mn></mrow></math></span> and <span><math><mrow><mi>n</mi><mo>≥</mo><mn>0</mn></mrow></math></span> are constants. We estimate the best-fit values of the model parameters using the Observational Hubble Data (OHD) comprising 31 data points of Cosmic Chronometers (CC) and the Pantheon+SHOES dataset comprising 1701 data points, employing the minimum chi-square method and the Markov Chain Monte Carlo (MCMC) technique, yielding <span><math><msubsup><mrow><mi>n</mi><mo>=</mo><mn>2</mn><mo>.</mo><mn>08</mn></mrow><mrow><mo>−</mo><mn>0</mn><mo>.</mo><mn>10</mn></mrow><mrow><mo>+</mo><mn>0</mn><mo>.</mo><mn>09</mn></mrow></msubsup></math></span> and <span><math><mrow><msub><mrow><mi>H</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>=</mo><msubsup><mrow><mn>74</mn><mo>.</mo><mn>07</mn></mrow><mrow><mo>−</mo><mn>2</mn><mo>.</mo><mn>32</mn></mrow><mrow><mo>+</mo><mn>2</mn><mo>.</mo><mn>30</mn></mrow></msubsup></mrow></math></span> for OHD, and <span><math><msubsup><mrow><mi>n</mi><mo>=</mo><mn>2</mn><mo>.</mo><mn>80</mn></mrow><mrow><mo>−</mo><mn>0</mn><mo>.</mo><mn>07</mn></mrow><mrow><mo>+</mo><mn>0</mn><mo>.</mo><mn>07</mn></mrow></msubsup></math></span> and <span><math><mrow><msub><mrow><mi>H</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>=</mo><msubsup><mrow><mn>74</mn><mo>.</mo><mn>63</mn></mrow><mrow><mo>−</mo><mn>0</mn><mo>.</mo><mn>22</mn></mrow><mrow><mo>+</mo><mn>0</mn><mo>.</mo><mn>21</mn></mrow></msubsup></mrow></math></span> for Pantheon+SHOES dataset. The evolution of the deceleration parameter indicates transition from an early decelerating phase to the current accelerating expansion phase of the universe in our model. Furthermore, the evolution of the deceleration parameter predicts a future transition into a super-acceleration phase of the universe. Moreover, to explore some key cosmological quantities such as energy density, pressure, equation of state parameter, the string tension density, we consider the quadrati
{"title":"Exploring the evolution of a non-static plane symmetric universe with cosmic strings and LVDP in f(Q) gravity","authors":"Syed Mudassir Syed Iqbal, G.U. Khapekar","doi":"10.1016/j.newast.2025.102455","DOIUrl":"10.1016/j.newast.2025.102455","url":null,"abstract":"<div><div>In this study, we have investigated the non-static plane symmetric space–time with perfect fluid containing cosmic string in the frame work of <span><math><mrow><mi>f</mi><mfenced><mrow><mi>Q</mi></mrow></mfenced></mrow></math></span> gravity in which the non-metricity scalar <span><math><mi>Q</mi></math></span> describes the gravitational interaction. To find exact solutions for the field equations, we assume the metric potentials relation as <span><math><mrow><msup><mrow><mi>e</mi></mrow><mrow><mi>h</mi></mrow></msup><mo>=</mo><msup><mrow><mi>s</mi></mrow><mrow><mi>m</mi></mrow></msup></mrow></math></span>, where <span><math><mrow><mi>m</mi><mo>≠</mo><mfrac><mrow><mn>1</mn></mrow><mrow><mn>2</mn></mrow></mfrac></mrow></math></span> is an arbitrary constant and the linearly varying deceleration parameter <span><math><mrow><mi>q</mi><mfenced><mrow><mi>t</mi></mrow></mfenced><mo>=</mo><mo>−</mo><mi>k</mi><mi>t</mi><mo>+</mo><mi>n</mi><mo>−</mo><mn>1</mn></mrow></math></span>, where <span><math><mrow><mi>k</mi><mo>≥</mo><mn>0</mn></mrow></math></span> and <span><math><mrow><mi>n</mi><mo>≥</mo><mn>0</mn></mrow></math></span> are constants. We estimate the best-fit values of the model parameters using the Observational Hubble Data (OHD) comprising 31 data points of Cosmic Chronometers (CC) and the Pantheon+SHOES dataset comprising 1701 data points, employing the minimum chi-square method and the Markov Chain Monte Carlo (MCMC) technique, yielding <span><math><msubsup><mrow><mi>n</mi><mo>=</mo><mn>2</mn><mo>.</mo><mn>08</mn></mrow><mrow><mo>−</mo><mn>0</mn><mo>.</mo><mn>10</mn></mrow><mrow><mo>+</mo><mn>0</mn><mo>.</mo><mn>09</mn></mrow></msubsup></math></span> and <span><math><mrow><msub><mrow><mi>H</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>=</mo><msubsup><mrow><mn>74</mn><mo>.</mo><mn>07</mn></mrow><mrow><mo>−</mo><mn>2</mn><mo>.</mo><mn>32</mn></mrow><mrow><mo>+</mo><mn>2</mn><mo>.</mo><mn>30</mn></mrow></msubsup></mrow></math></span> for OHD, and <span><math><msubsup><mrow><mi>n</mi><mo>=</mo><mn>2</mn><mo>.</mo><mn>80</mn></mrow><mrow><mo>−</mo><mn>0</mn><mo>.</mo><mn>07</mn></mrow><mrow><mo>+</mo><mn>0</mn><mo>.</mo><mn>07</mn></mrow></msubsup></math></span> and <span><math><mrow><msub><mrow><mi>H</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>=</mo><msubsup><mrow><mn>74</mn><mo>.</mo><mn>63</mn></mrow><mrow><mo>−</mo><mn>0</mn><mo>.</mo><mn>22</mn></mrow><mrow><mo>+</mo><mn>0</mn><mo>.</mo><mn>21</mn></mrow></msubsup></mrow></math></span> for Pantheon+SHOES dataset. The evolution of the deceleration parameter indicates transition from an early decelerating phase to the current accelerating expansion phase of the universe in our model. Furthermore, the evolution of the deceleration parameter predicts a future transition into a super-acceleration phase of the universe. Moreover, to explore some key cosmological quantities such as energy density, pressure, equation of state parameter, the string tension density, we consider the quadrati","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":"121 ","pages":"Article 102455"},"PeriodicalIF":1.9,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144713342","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}
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