Chinese Journal of Astronomy and Astrophysics最新文献_第6页

Model-synthesized rate of Type Ia Supernovae and its influence on the chemical enrichment of the ISM Ia型超新星的模型合成速率及其对ISM化学富集的影响

Chinese Journal of Astronomy and Astrophysics Pub Date : 2008-02-01 DOI: 10.1088/1009-9271/8/1/06

W. Guo, Fenghui Zhang, X. Meng, Zhongmu Li, Zhanwen Han

{"title":"Model-synthesized rate of Type Ia Supernovae and its influence on the chemical enrichment of the ISM","authors":"W. Guo, Fenghui Zhang, X. Meng, Zhongmu Li, Zhanwen Han","doi":"10.1088/1009-9271/8/1/06","DOIUrl":"https://doi.org/10.1088/1009-9271/8/1/06","url":null,"abstract":"Using Hurley's rapid binary stellar evolution code, we have studied the model-synthesized rate of Type Ia Supernovae (SNe Ia) and its influence on the chemical enrichment of the interstellar medium ejected by stellar populations. We adopt two popular scenarios, i.e., single degenerate scenario (SD) and double degenerate scenario (DD), for the progenitors of SNe Ia to calculate the rates of SNe Ia. Rates calculated in this work agree with that of Hachisu et al. and Han & Podsiadlowski, but are different from that usually adopted in chemical evolution models of galaxies. We apply the rates of SNe Ia to the chemical enrichment (especially Fe enrichment), then compare the results with previous studies. As known SNe Ia slightly affect the enrichment of C, N, O and Mg elements, while significantly affect the enrichment of Fe. We find that the occurrence and the value of the Fe enrichment in our models are earlier and smaller than that commonly adopted in chemical evolution models. We also study the evolution of [Mg/Fe] ratios, which are almost reciprocals of the Fe enrichment. The study may provide constraints on the free parameters of chemical evolution models of galaxies and evolutionary population synthesis.","PeriodicalId":124495,"journal":{"name":"Chinese Journal of Astronomy and Astrophysics","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128540713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

A close correlation between the spectral lags and redshifts of gamma-ray bursts 伽玛射线暴的光谱滞后和红移之间的密切关系

Chinese Journal of Astronomy and Astrophysics Pub Date : 2008-02-01 DOI: 10.1088/1009-9271/8/1/08

T. Yi, G. Xie, Fu-Wen Zhang

引用次数: 5

An Approach of Tropospheric Correction for VLBI Phase-Referencing using GPS Data 基于GPS数据的VLBI相位参考对流层校正方法

Chinese Journal of Astronomy and Astrophysics Pub Date : 2008-02-01 DOI: 10.1088/1009-9271/8/1/14

Bo Zhang, Xing-wu Zheng, Jinling Li, Ye Xu

引用次数: 1

Weak Elliptical Distortion of the Milky Way Potential traced by Open Clusters 疏散星团追踪的银河系势的弱椭圆畸变

Chinese Journal of Astronomy and Astrophysics Pub Date : 2008-02-01 DOI: 10.1088/1009-9271/8/1/10

Zi Zhu

引用次数: 4

A New Approach for Estimating Kinetic Luminosity of Jet in AGNs 一种估算agn中射流动力学光度的新方法

Chinese Journal of Astronomy and Astrophysics Pub Date : 2008-02-01 DOI: 10.1088/1009-9271/8/1/04

M. Ma, Xinwu Cao, D. Jiang, M. Gu

引用次数: 6

Geometry of Broad Line Regions of Active Galactic Nuclei 活动星系核宽线区域的几何学

Chinese Journal of Astronomy and Astrophysics Pub Date : 2008-02-01 DOI: 10.1088/1009-9271/8/1/05

Xiao-Rong Lü

引用次数: 4

Gaseous versus Stellar Velocity Dispersion in Emission-Line Galaxies 发射线星系中气体与恒星速度色散

Chinese Journal of Astronomy and Astrophysics Pub Date : 2008-02-01 DOI: 10.1088/1009-9271/8/1/03

Xiaoyan Chen, C. Hao, Jing Wang

{"title":"Gaseous versus Stellar Velocity Dispersion in Emission-Line Galaxies","authors":"Xiaoyan Chen, C. Hao, Jing Wang","doi":"10.1088/1009-9271/8/1/03","DOIUrl":"https://doi.org/10.1088/1009-9271/8/1/03","url":null,"abstract":"We compare the ionized gas velocity dispersion σgas with the stellar velocity dispersion σ in star-forming galaxies, composite galaxies, Low Ionization Nuclear Emission-line Regions (LINERs) and Seyfert 2s, compiled from a cross-identification of Sloan Digital Sky Survey Fourth Data Release (SDSS DR4) and Point Source Catalogue Redshift Survey (PSCz). We measure σgas from the FWHMs of emission lines (Hα, [NII]λλ6548, 6583 and [SII]λλ6716, 6731). A significant correlation between the gas and stellar velocity dispersion exists, despite substantial scatter. The mean value of the gas to stellar velocity dispersion ratio is close to unity. This suggests that gas velocity dispersion can substitute for the stellar velocity dispersion as a tracer of the gravitational potential well for all the four types of galaxies, but the involved uncertainties are different from type to type. We also studied gas/σ as a function of the redshift and the axial ratio to test the effects of aperture and galaxy inclination, and found that both effects are weak. Finally we checked the trend of gas/σ with the infrared luminosity and found no significant correlation.","PeriodicalId":124495,"journal":{"name":"Chinese Journal of Astronomy and Astrophysics","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114939123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Simultaneous Multi-Wavelength Observations of the TeV Blazar Mrk 421 during February − March, 2003: X-Ray and NIR Correlated Variability ∗ 2003年2 - 3月TeV Blazar Mrk 421的同步多波长观测:x射线和近红外相关变率*

Chinese Journal of Astronomy and Astrophysics Pub Date : 2008-01-08 DOI: 10.1088/1009-9271/8/4/03

Alok C. Gupta, B. Acharya, D. Bose, V. Chitnis, J. F. C. F. Astrophysics, G. University, Guangzhou, C. T. I. O. F. Research, Homi Bhabha Road, Colaba, Mumbai, India.

{"title":"Simultaneous Multi-Wavelength Observations of the TeV Blazar Mrk 421 during February − March, 2003: X-Ray and NIR Correlated Variability ∗","authors":"Alok C. Gupta, B. Acharya, D. Bose, V. Chitnis, J. F. C. F. Astrophysics, G. University, Guangzhou, C. T. I. O. F. Research, Homi Bhabha Road, Colaba, Mumbai, India.","doi":"10.1088/1009-9271/8/4/03","DOIUrl":"https://doi.org/10.1088/1009-9271/8/4/03","url":null,"abstract":"We report the result of simultaneous multi-wavelength observations of the TeV blazar Mrk 421 during February–March 2003. We observed Mrk 421 using the Pachmarhi Array of Cerenkov Telescopes (PACT) of Tata Institute of Fundamental Research at Pachmarhi, India. Other simultaneous data were taken from the literature and public data archives. We have analyzed the high quality X-ray (2–20 keV) observations from the NASA Rossi X-Ray Timing Explorer (RXTE). We obtained a possible correlated variability between X-ray and J band (1.25 μ) near infrared (NIR) wavelength. This is the first case of X-ray and NIR correlated variability in Mrk 421 or any high energy peaked (HBL) blazar. The correlated variability reported here indicates a similar origin for the NIR and X-ray emissions. The emission is not affected much by the environment of the surrounding medium of the central engine of Mrk 421. The observations are consistent with the shock-in-jet model for the emissions.","PeriodicalId":124495,"journal":{"name":"Chinese Journal of Astronomy and Astrophysics","volume":"115 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127947945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

Excitation of Annual Polar Motion by the Pacific, Atlantic and Indian Oceans 太平洋、大西洋和印度洋对年极运动的激发

Chinese Journal of Astronomy and Astrophysics Pub Date : 2007-12-20 DOI: 10.1088/1009-9271/7/6/11

Jin Ma, Yonghong Zhou, D. Liao, Jianli Chen

引用次数: 3

Determination of the Topology Skeleton of Magnetic Fields in a Solar Active Region 太阳活动区磁场拓扑骨架的确定

Chinese Journal of Astronomy and Astrophysics Pub Date : 2007-12-20 DOI: 10.1088/1009-9271/8/2/01

Hui Zhao, Jingxiu Wang, Jun Zhang, C. Xiao, Haimin Wang

{"title":"Determination of the Topology Skeleton of Magnetic Fields in a Solar Active Region","authors":"Hui Zhao, Jingxiu Wang, Jun Zhang, C. Xiao, Haimin Wang","doi":"10.1088/1009-9271/8/2/01","DOIUrl":"https://doi.org/10.1088/1009-9271/8/2/01","url":null,"abstract":"Magnetic topology has been a key to the understanding of magnetic energy release mechanism. Based on observed vector magnetograms, we have determined the three-dimensional (3D) topology skeleton of the magnetic fields in the active region NOAA 10720. The skeleton consists of six 3D magnetic nulls and a network of corresponding spines, fans, and null-null lines. For the first time, we have identified a spiral magnetic null in Sun's corona. The magnetic lines of force twisted around the spine of the null, forming a `magnetic wreath' with excess of free magnetic energy and resembling observed brightening structures at extra-ultraviolet (EUV) wavebands. We found clear evidence of topology eruptions which are referred to as catastrophic changes of topology skeleton associated with a coronal mass ejection (CME) and an explosive X-ray flare. These results shed new lights on the structural complexity and its role in explosive magnetic activity. The concept of flux rope has been widely used in modelling explosive magnetic activity, although their observational identity is rather obscure or, at least, lacking of necessary details up to date. We suggest that the magnetic wreath associated with the 3D spiral null is likely an important class of the physical entity of flux ropes.","PeriodicalId":124495,"journal":{"name":"Chinese Journal of Astronomy and Astrophysics","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133168160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 25