Pub Date : 2024-03-13DOI: 10.1016/j.newast.2024.102224
Jie Zheng , Linqiao Jiang , Jianfeng Tian
This paper introduces an astronomical image alignment algorithm. This algorithm uses the means of the rows and columns of the original image for alignment, and finds the optimal offset corresponding to the maximum similarity by comparing different offsets between images. The similarity is evaluated by the standard deviation of the quotient divided by the means. This paper also discusses the theoretical feasibility of this algorithm. Through practical testing, it has been confirmed that the algorithm is fast and robust.
{"title":"A fast photometric image alignment algorithm with row and column means","authors":"Jie Zheng , Linqiao Jiang , Jianfeng Tian","doi":"10.1016/j.newast.2024.102224","DOIUrl":"https://doi.org/10.1016/j.newast.2024.102224","url":null,"abstract":"<div><p>This paper introduces an astronomical image alignment algorithm. This algorithm uses the means of the rows and columns of the original image for alignment, and finds the optimal offset corresponding to the maximum similarity by comparing different offsets between images. The similarity is evaluated by the standard deviation of the quotient divided by the means. This paper also discusses the theoretical feasibility of this algorithm. Through practical testing, it has been confirmed that the algorithm is fast and robust.</p></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140134014","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 : 2024-03-11DOI: 10.1016/j.newast.2024.102225
M. Umair Shahzad , Aqsa Mehmood , Ramish Gohar , Ali Övgün
This paper is devoted to study the thermodynamic topological defects, Joule–Thomson () and Maxwell’s equal area law of Phantom RN AdS black holes (BHs). The inversion temperatures and inversion curves are obtained and by using the isenthalpic curves in the temperature–pressure () plane to locate the cooling and heating regions. Using Maxwell’s equal-area law, we select different independent conjugate variables to study the phase transitions of Phantom RN AdS BHs. We find that phase transition rely on the electric potential and horizon radius of the BH when its charge is constant. Phase transition of Phantom RN AdS BH are proportional to the ratio of event horizon to its cosmological constant, where the latter is assumed to be constant. Moreover, we consider the Phantom RN AdS BH as defects with a topological nature within thermodynamic domain and examine the local and global topology by computing the winding numbers at the defects, which concludes that the overall topological charge is either equal to 0 or 1.
{"title":"Joule Thomson expansion, Maxwell equal area law and topological interpretation of Phantom RN AdS black holes","authors":"M. Umair Shahzad , Aqsa Mehmood , Ramish Gohar , Ali Övgün","doi":"10.1016/j.newast.2024.102225","DOIUrl":"10.1016/j.newast.2024.102225","url":null,"abstract":"<div><p>This paper is devoted to study the thermodynamic topological defects, Joule–Thomson (<span><math><mrow><mi>J</mi><mo>−</mo><mi>T</mi></mrow></math></span>) and Maxwell’s equal area law of Phantom RN AdS black holes (BHs). The inversion temperatures and inversion curves are obtained and by using the isenthalpic curves in the temperature–pressure (<span><math><mrow><mi>T</mi><mo>−</mo><mi>P</mi></mrow></math></span>) plane to locate the cooling and heating regions. Using Maxwell’s equal-area law, we select different independent conjugate variables to study the phase transitions of Phantom RN AdS BHs. We find that phase transition rely on the electric potential and horizon radius of the BH when its charge is constant. Phase transition of Phantom RN AdS BH are proportional to the ratio of event horizon to its cosmological constant, where the latter is assumed to be constant. Moreover, we consider the Phantom RN AdS BH as defects with a topological nature within thermodynamic domain and examine the local and global topology by computing the winding numbers at the defects, which concludes that the overall topological charge is either equal to 0 or 1.</p></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140097593","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 : 2024-03-07DOI: 10.1016/j.newast.2024.102216
Amos V. Mathias, Jason M. Mkenyeleye, Jefta M. Sunzu
The current paper presents a double-layered neutral anisotropic stellar model in general relativistic setting. The model is developed by using Einstein field equations and class I embedding condition. We consider the core with quark matter obeying linear equation of state and envelope layer with gaseous matter admitting Chaplygin gas equation of state. The interior and exterior metric coefficients match smoothly at the interface of core and envelope layers and at the stellar surface. The profiles for matter variables, stability and energy conditions show acceptable trend for physical stellar models. In this model, stellar masses and radii consistent with compact stars HerX-1, 4U1538-52, SAXJ1808.4-3658, CenX-3 and SMCX-1 are generated. We note that studies of multi-layered stars with gaseous envelope and embedding class I condition are missing in investigations conducted in the past.
本文介绍了广义相对论环境下的双层中性各向异性恒星模型。该模型是利用爱因斯坦场方程和 I 类嵌入条件建立的。我们认为核心层的夸克物质遵守线性状态方程,包络层的气态物质遵守查普利金气体状态方程。在核心层和包络层的界面以及恒星表面,内部和外部度量系数平稳匹配。物质变量、稳定性和能量条件的曲线显示出物理恒星模型可以接受的趋势。在这个模型中,产生了与紧凑型恒星 HerX-1、4U1538-52、SAXJ1808.4-3658、CenX-3 和 SMCX-1 一致的恒星质量和半径。我们注意到在过去的研究中缺少对具有气态包膜和嵌入等级 I 条件的多层恒星的研究。
{"title":"Double-layered anisotropic stellar model of embedding class I with gaseous envelope","authors":"Amos V. Mathias, Jason M. Mkenyeleye, Jefta M. Sunzu","doi":"10.1016/j.newast.2024.102216","DOIUrl":"https://doi.org/10.1016/j.newast.2024.102216","url":null,"abstract":"<div><p>The current paper presents a double-layered neutral anisotropic stellar model in general relativistic setting. The model is developed by using Einstein field equations and class I embedding condition. We consider the core with quark matter obeying linear equation of state and envelope layer with gaseous matter admitting Chaplygin gas equation of state. The interior and exterior metric coefficients match smoothly at the interface of core and envelope layers and at the stellar surface. The profiles for matter variables, stability and energy conditions show acceptable trend for physical stellar models. In this model, stellar masses and radii consistent with compact stars HerX-1, 4U1538-52, SAXJ1808.4-3658, CenX-3 and SMCX-1 are generated. We note that studies of multi-layered stars with gaseous envelope and embedding class I condition are missing in investigations conducted in the past.</p></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140069650","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 : 2024-03-05DOI: 10.1016/j.newast.2024.102215
Chen Long , Sheng Zheng , Yao Huang , Shuguang Zeng , Zhibo Jiang , Zhiwei Chen , Xiaoyu Luo , Yu Jiang , Xiangyun Zeng
The detection and statistical analysis of molecular clumps can provide important clues for understanding star formation. In order to improve the reliability of candidates identified by molecular clump detection algorithm, we present a molecular clump verification network (called MCVnet) based on supervised learning in this paper. First, a molecular clump detection algorithm is used to identify the candidates for the clumps. Then the confidence level of each candidate clump is calculated using the MCVnet. Finally, the clumps are classified into three classes (”Yes”,”No”,”Uncertain”) according to the output confidence. The automatic verification algorithm eliminates the clump candidates with low confidence, thus improving the accuracy of the final detection performance. The validation effect of MCVnet is verified in the Milky Way Imaging Scroll Painting (MWISP) project within the region l=+180 to +190, b=-5 to +5 and v=-200 km s−1 to +200 km s−1. The experimental results show that the precision of MCVnet agree with the manual verification by more than 90%, which illustrates the effectiveness of the method in this paper for clump verification. Moreover, the combination of Local Density Clustering (LDC) and MCVnet increases the accuracy of LDC.
分子团块的探测和统计分析可以为理解恒星的形成提供重要线索。为了提高分子团块探测算法识别出的候选分子团块的可靠性,我们在本文中提出了一种基于监督学习的分子团块验证网络(称为 MCVnet)。首先,使用分子团块检测算法识别候选团块。然后,使用 MCVnet 计算每个候选团块的置信度。最后,根据输出的置信度将分子团块分为三类("是"、"否 "和 "不确定")。自动验证算法剔除了置信度低的候选树块,从而提高了最终检测性能的准确性。MCVnet的验证效果在银河系成像卷轴绘画(MWISP)项目中得到了验证,区域范围为l=+180∘至+190∘,b=-5∘至+5∘,v=-200 km s-1 至 +200 km s-1。实验结果表明,MCVnet 的精确度与人工验证的吻合度超过 90%,这说明本文的方法在团块验证方面是有效的。此外,局部密度聚类(LDC)与 MCVnet 的结合提高了 LDC 的精度。
{"title":"Automatically verifying molecular clumps based on supervised learning","authors":"Chen Long , Sheng Zheng , Yao Huang , Shuguang Zeng , Zhibo Jiang , Zhiwei Chen , Xiaoyu Luo , Yu Jiang , Xiangyun Zeng","doi":"10.1016/j.newast.2024.102215","DOIUrl":"https://doi.org/10.1016/j.newast.2024.102215","url":null,"abstract":"<div><p>The detection and statistical analysis of molecular clumps can provide important clues for understanding star formation. In order to improve the reliability of candidates identified by molecular clump detection algorithm, we present a molecular clump verification network (called MCVnet) based on supervised learning in this paper. First, a molecular clump detection algorithm is used to identify the candidates for the clumps. Then the confidence level of each candidate clump is calculated using the MCVnet. Finally, the clumps are classified into three classes (”Yes”,”No”,”Uncertain”) according to the output confidence. The automatic verification algorithm eliminates the clump candidates with low confidence, thus improving the accuracy of the final detection performance. The validation effect of MCVnet is verified in the Milky Way Imaging Scroll Painting (MWISP) project within the region l=+180<span><math><msup><mrow></mrow><mrow><mo>∘</mo></mrow></msup></math></span> to +190<span><math><msup><mrow></mrow><mrow><mo>∘</mo></mrow></msup></math></span>, b=-5<span><math><msup><mrow></mrow><mrow><mo>∘</mo></mrow></msup></math></span> to +5<span><math><msup><mrow></mrow><mrow><mo>∘</mo></mrow></msup></math></span> and v=-200 km s<sup>−1</sup> to +200 km s<sup>−1</sup>. The experimental results show that the precision of MCVnet agree with the manual verification by more than 90%, which illustrates the effectiveness of the method in this paper for clump verification. Moreover, the combination of Local Density Clustering (LDC) and MCVnet increases the accuracy of LDC.</p></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140051543","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 : 2024-02-29DOI: 10.1016/j.newast.2024.102214
D.D. Pawar , D.K. Raut , A.P. Kale
The main objective of this article is to study the fractal FRW cosmological model consisting two forms of dark energy. We studied behavior of the universe in a fractal framework using dark energy accommodated in our universe. The solution of field equations are obtained by using Hubble parameter for transit scale factor . We have obtained the best fitting values of the model parameters and by constraining our model with latest Hubble and SNe-Ia data sets . Finally we perform state-finder diagnosis and observe that obtained model close to standard CDM model.
{"title":"Two forms of dark energy in fractal cosmological model using specific Hubble parameter","authors":"D.D. Pawar , D.K. Raut , A.P. Kale","doi":"10.1016/j.newast.2024.102214","DOIUrl":"10.1016/j.newast.2024.102214","url":null,"abstract":"<div><p>The main objective of this article is to study the fractal FRW cosmological model consisting two forms of dark energy. We studied behavior of the universe in a fractal framework using dark energy accommodated in our universe. The solution of field equations are obtained by using Hubble parameter for transit scale factor <span><math><mrow><mi>H</mi><mrow><mo>(</mo><mi>z</mi><mo>)</mo></mrow><mo>=</mo><mi>ϵ</mi><mfenced><mrow><msup><mrow><mi>a</mi></mrow><mrow><mo>−</mo><mi>δ</mi></mrow></msup><mo>+</mo><mi>λ</mi></mrow></mfenced></mrow></math></span> . We have obtained the best fitting values of the model parameters <span><math><mrow><mi>ϵ</mi><mo>,</mo><mi>δ</mi></mrow></math></span> and <span><math><mi>λ</mi></math></span> by constraining our model with latest Hubble and SNe-Ia data sets . Finally we perform state-finder diagnosis and observe that obtained model close to standard <span><math><mi>Λ</mi></math></span>CDM model.</p></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140036721","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 : 2024-02-29DOI: 10.1016/j.newast.2024.102212
Farzan Mushtaq, Xia Tiecheng
Weak gravitational lensing of the primary scalar hair black hole is proposed within this work. We can figure out the deflection angle of light by applying the Gibbons and Werner approach with a primary scalar hair black hole. To do this, we compute the Gaussian curvature and find the deflection angle of the weak field limits by applying Gauss-Bonnet theorem. Furthermore, we compute the deflection angle of light when it comes across both plasma and non-plasma field. We also study how the deflection angle behaves graphically in both cases.
{"title":"Deflection angle of light in an black hole with primary scalar hair geometry","authors":"Farzan Mushtaq, Xia Tiecheng","doi":"10.1016/j.newast.2024.102212","DOIUrl":"https://doi.org/10.1016/j.newast.2024.102212","url":null,"abstract":"<div><p>Weak gravitational lensing of the primary scalar hair black hole is proposed within this work. We can figure out the deflection angle of light by applying the Gibbons and Werner approach with a primary scalar hair black hole. To do this, we compute the Gaussian curvature and find the deflection angle of the weak field limits by applying Gauss-Bonnet theorem. Furthermore, we compute the deflection angle of light when it comes across both plasma and non-plasma field. We also study how the deflection angle behaves graphically in both cases.</p></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140015346","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 : 2024-02-29DOI: 10.1016/j.newast.2024.102211
M. Sharif, M. Zeeshan Gul, Nusrat Fatima
The main objective of this manuscript is to investigate the bouncing cosmology in the background of gravity, where defines the non-metricity. For this purpose, we use the reconstruction approach and consider a flat Friedmann–Robertson–Walker spacetime with perfect matter configuration. We examine how the first contracting phase gives the expansion by using a temporal derivative of the scale factor, i.e., , and give contraction, bounce point and expansion phases, respectively. Further, we use the order reduction method to solve the modified field equations as these are very difficult due to the presence of additional non-linear expressions. It is analyzed that the original singularity of the universe diminishes for the required bounce conditions. We conclude that the acceleration occurs near the bouncing point and the considered models are consistent with the current cosmic accelerated expansion.
{"title":"Analysis of bouncing cosmology in non-Riemannian geometry","authors":"M. Sharif, M. Zeeshan Gul, Nusrat Fatima","doi":"10.1016/j.newast.2024.102211","DOIUrl":"https://doi.org/10.1016/j.newast.2024.102211","url":null,"abstract":"<div><p>The main objective of this manuscript is to investigate the bouncing cosmology in the background of <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>Q</mi><mo>)</mo></mrow></mrow></math></span> gravity, where <span><math><mi>Q</mi></math></span> defines the non-metricity. For this purpose, we use the reconstruction approach and consider a flat Friedmann–Robertson–Walker spacetime with perfect matter configuration. We examine how the first contracting phase gives the expansion by using a temporal derivative of the scale factor, i.e., <span><math><mrow><mover><mrow><mi>a</mi></mrow><mrow><mo>̇</mo></mrow></mover><mo><</mo><mn>0</mn></mrow></math></span>, <span><math><mrow><mover><mrow><mi>a</mi></mrow><mrow><mo>̇</mo></mrow></mover><mo>=</mo><mn>0</mn></mrow></math></span> and <span><math><mrow><mover><mrow><mi>a</mi></mrow><mrow><mo>̇</mo></mrow></mover><mo>></mo><mn>0</mn></mrow></math></span> give contraction, bounce point and expansion phases, respectively. Further, we use the order reduction method to solve the modified field equations as these are very difficult due to the presence of additional non-linear expressions. It is analyzed that the original singularity of the universe diminishes for the required bounce conditions. We conclude that the acceleration occurs near the bouncing point and the considered <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>Q</mi><mo>)</mo></mrow></mrow></math></span> models are consistent with the current cosmic accelerated expansion.</p></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140015347","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 : 2024-02-28DOI: 10.1016/j.newast.2024.102210
R. Wes Tobin , Robert C. Berrington
We present BVR+TESS differential photometry of an eclipsing binary system NSVS 2910034. A period analysis reveals unusual variations that are inconsistent with systemic orbital period changes and may be due to surface activity. The best fit models are consistent with a W-type W UMa overcontact binary, consisting of a less massive G7 spectral type star and a more massive K1 spectral type star. An O’Connell effect is present and analyzed. The best fit model represents a very large hot spot that may indicate significant chromospheric activity across a large portion of the stellar surface of the K star.
我们展示了对食双星系统 NSVS 2910034 的 BVRC+TESS 差分光度测量。周期分析发现了与系统轨道周期变化不一致的异常变化,可能是由于表面活动造成的。最佳拟合模型与 W 型 W UMa 超接触双星一致,由一颗质量较小的 G7 光谱型恒星和一颗质量较大的 K1 光谱型恒星组成。奥康纳尔效应存在并得到了分析。最佳拟合模型代表了一个非常大的热点,这可能表明在 K 星的大部分恒星表面都有显著的色球活动。
{"title":"Photometric study of the overcontact binary NSVS2910034","authors":"R. Wes Tobin , Robert C. Berrington","doi":"10.1016/j.newast.2024.102210","DOIUrl":"https://doi.org/10.1016/j.newast.2024.102210","url":null,"abstract":"<div><p>We present BVR<span><math><msub><mrow></mrow><mrow><mi>C</mi></mrow></msub></math></span>+TESS differential photometry of an eclipsing binary system NSVS 2910034. A period analysis reveals unusual variations that are inconsistent with systemic orbital period changes and may be due to surface activity. The best fit models are consistent with a W-type W UMa overcontact binary, consisting of a less massive G7 spectral type star and a more massive K1 spectral type star. An O’Connell effect is present and analyzed. The best fit model represents a very large hot spot that may indicate significant chromospheric activity across a large portion of the stellar surface of the K star.</p></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140031207","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 : 2024-02-27DOI: 10.1016/j.newast.2024.102213
Noam Soker
I identify a point-symmetric morphology of the supernova remnant (SNR) G352.7-0.1 and propose that the outer axially-symmetric structure is the remnant of a common envelope evolution (CEE) of the progenitor system, while the inner structure is the ejecta of a thermonuclear explosion triggered by the merger of a white dwarf (WD) and the core of an asymptotic giant branch (AGB) star. The main radio structure of SNR G352.7-0.1 forms an outer (large) ellipse. The bright X-ray emitting gas forms a smaller ellipse with a symmetry axis inclined to the symmetry axis of the large radio ellipse. The high abundance of iron and the energy of its X-ray lines suggest a type Ia supernova (SN Ia). The massive swept-up gas suggests a relatively massive progenitor system. I propose a scenario with progenitors of initial masses of and . At a later phase, the WD remnant of the primary star and the AGB secondary star experience a CEE that ejects the circumstellar material that swept up more ISM to form the large elliptical radio structure. An explosion during the merger of the WD with the core of the AGB star triggered a super-Chandrasekhar thermonuclear explosion that formed the inner structure that is bright in X-ray. A tertiary star in the system caused the misalignment of the two symmetry axes. This study adds to the wide variety of evolutionary routes within the scenarios of normal and peculiar SNe Ia.
我确定了超新星残余物(SNR)G352.7-0.1的点对称形态,并提出外部轴对称结构是原生系统共同包层演化(CEE)的残余物,而内部结构则是白矮星(WD)和渐近巨枝星(AGB)内核合并引发的热核爆炸的喷出物。SNR G352.7-0.1的主要射电结构形成了一个外(大)椭圆。明亮的 X 射线发射气体形成了一个较小的椭圆,其对称轴与大射电椭圆的对称轴呈倾斜状。铁的高丰度及其 X 射线的能量表明这是一颗 Ia 型超新星(SN Ia)。大量被卷起的气体表明这是一个相对大质量的原生系统。我提出的设想是,祖星的初始质量为MZAMS,1≃5-7M⊙和MZAMS,2≃4-5M⊙。在较晚的阶段,主星的WD残余物和AGB次星经历了一次CEE,喷射出的星周物质卷起了更多的ISM,形成了大椭圆射电结构。WD与AGB恒星内核合并过程中的一次爆炸引发了超级钱德拉塞卡热核爆炸,形成了在X射线下非常明亮的内部结构。系统中的一颗三级恒星导致了两个对称轴的错位。这项研究增加了正常和奇特SNE Ia情景中演化路线的多样性。
{"title":"Explaining supernova remnant G352.7-0.1 as a peculiar type Ia supernova inside a planetary nebula","authors":"Noam Soker","doi":"10.1016/j.newast.2024.102213","DOIUrl":"https://doi.org/10.1016/j.newast.2024.102213","url":null,"abstract":"<div><p>I identify a point-symmetric morphology of the supernova remnant (SNR) G352.7-0.1 and propose that the outer axially-symmetric structure is the remnant of a common envelope evolution (CEE) of the progenitor system, while the inner structure is the ejecta of a thermonuclear explosion triggered by the merger of a white dwarf (WD) and the core of an asymptotic giant branch (AGB) star. The main radio structure of SNR G352.7-0.1 forms an outer (large) ellipse. The bright X-ray emitting gas forms a smaller ellipse with a symmetry axis inclined to the symmetry axis of the large radio ellipse. The high abundance of iron and the energy of its X-ray lines suggest a type Ia supernova (SN Ia). The massive swept-up gas suggests a relatively massive progenitor system. I propose a scenario with progenitors of initial masses of <span><math><mrow><msub><mrow><mi>M</mi></mrow><mrow><mi>ZAMS,1</mi></mrow></msub><mo>≃</mo><mn>5</mn><mtext>–</mtext><mn>7</mn><msub><mrow><mi>M</mi></mrow><mrow><mo>⊙</mo></mrow></msub></mrow></math></span> and <span><math><mrow><msub><mrow><mi>M</mi></mrow><mrow><mi>ZAMS,2</mi></mrow></msub><mo>≃</mo><mn>4</mn><mtext>–</mtext><mn>5</mn><msub><mrow><mi>M</mi></mrow><mrow><mo>⊙</mo></mrow></msub></mrow></math></span>. At a later phase, the WD remnant of the primary star and the AGB secondary star experience a CEE that ejects the circumstellar material that swept up more ISM to form the large elliptical radio structure. An explosion during the merger of the WD with the core of the AGB star triggered a super-Chandrasekhar thermonuclear explosion that formed the inner structure that is bright in X-ray. A tertiary star in the system caused the misalignment of the two symmetry axes. This study adds to the wide variety of evolutionary routes within the scenarios of normal and peculiar SNe Ia.</p></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139985516","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 : 2024-02-22DOI: 10.1016/j.newast.2024.102209
Deniz Yazıcı, Cengiz Yıldırım, Tolga Görüm
The second-largest outflow system on Mars is Kasei Valles. The southern branch of Kasei Valles includes two inner channels among the best-preserved examples of glacial and/or fluvial erosion. This study focuses on the landforms formed by surface processes within the midstream part of the southern branch of the Kasei Valles. We mapped the landforms and built a morpho-stratigraphical chronology using their cross-cutting relationships, and numerical crater dating. We interpret a complex geomorphological history, with various landforms in the study area, including fans, landslides, topographic barriers, strandlines, terraces and deeply incised canyons. Two coluvaial fans and a large landslide temporarily blocked the valles, forming topographical barriers to impound fluids (e.g., lava, mudflow, water). It has been suggested that the structures observed in the channels were formed by Bingham or Newtonian fluid. However, these fluids have disappeared but they have left the terraces and strandlines as their geomorphic imprints. The surface texture of the terraces implies that they were probably formed by a very low viscosity fluid that carved the fan, valley floor and formed terrace staircases and deep canyons. Crater statistics reveal two different temporal clusters of colluvial fan formation. The age of the older fan cluster in the Early Amazonian period, and the age of the younger fan cluster in the Late-Middle Amazonian period. The landslide is much younger and estimated to have formed 122 Ma ago, allowing us to constrain the timing of the latest erosional period. The youngest studied geomorphic features are the platy-textured deposits emplaced either as lavas or mudflows, aged 90 Ma, covering the floor of the valles. The strandlines defining the limits of the youngest erosional (thermal) process within the study area truncate the landslide but not the platy-textured features. Therefore, they are older than 90 Ma but younger than 122 Ma, implying environmental conditions sufficient to have allowed a liquid fluid body at the Martian surface during the Latest Amazonian period. Our data suggest that the presence of well-developed terraces between strandlines requires the presence of a fluid (e.g. water, liquid lava, mud) that ponded and subsequently evacuated from the study area.
{"title":"The timing of resurfacing events in Southern Kasei Valles","authors":"Deniz Yazıcı, Cengiz Yıldırım, Tolga Görüm","doi":"10.1016/j.newast.2024.102209","DOIUrl":"10.1016/j.newast.2024.102209","url":null,"abstract":"<div><p>The second-largest outflow system on Mars is Kasei Valles. The southern branch of Kasei Valles includes two inner channels among the best-preserved examples of glacial and/or fluvial erosion. This study focuses on the landforms formed by surface processes within the midstream part of the southern branch of the Kasei Valles. We mapped the landforms and built a morpho-stratigraphical chronology using their cross-cutting relationships, and numerical crater dating. We interpret a complex geomorphological history, with various landforms in the study area, including fans, landslides, topographic barriers, strandlines, terraces and deeply incised canyons. Two coluvaial fans and a large landslide temporarily blocked the valles, forming topographical barriers to impound fluids (e.g., lava, mudflow, water). It has been suggested that the structures observed in the channels were formed by Bingham or Newtonian fluid. However, these fluids have disappeared but they have left the terraces and strandlines as their geomorphic imprints. The surface texture of the terraces implies that they were probably formed by a very low viscosity fluid that carved the fan, valley floor and formed terrace staircases and deep canyons. Crater statistics reveal two different temporal clusters of colluvial fan formation. The age of the older fan cluster in the Early Amazonian period, and the age of the younger fan cluster in the Late-Middle Amazonian period. The landslide is much younger and estimated to have formed 122 Ma ago, allowing us to constrain the timing of the latest erosional period. The youngest studied geomorphic features are the platy-textured deposits emplaced either as lavas or mudflows, aged 90 Ma, covering the floor of the valles. The strandlines defining the limits of the youngest erosional (thermal) process within the study area truncate the landslide but not the platy-textured features. Therefore, they are older than 90 Ma but younger than 122 Ma, implying environmental conditions sufficient to have allowed a liquid fluid body at the Martian surface during the Latest Amazonian period. Our data suggest that the presence of well-developed terraces between strandlines requires the presence of a fluid (e.g. water, liquid lava, mud) that ponded and subsequently evacuated from the study area.</p></div>","PeriodicalId":54727,"journal":{"name":"New Astronomy","volume":null,"pages":null},"PeriodicalIF":2.0,"publicationDate":"2024-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139953897","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}