{"title":"吸积白矮星:WD组成对缓慢吸积过程中氦点火的影响","authors":"Harish Kumar, Abhinav Gupta, Siddharth Savyasachi Malu, Shashikant Gupta","doi":"10.1007/s12036-023-09931-1","DOIUrl":null,"url":null,"abstract":"<div><p>Understanding the explosion mechanism of type Ia supernova is among the most challenging issues in astrophysics. Accretion of matter on a carbon–oxygen (CO) white dwarf (WD) from a companion star is one of the most important keys in this regard. Our aim is to study the effects of WD composition on various parameters during the accretion of helium-rich matter at a slow rate. We have used the computer simulation code Modules for Experiments in Stellar Astrophysics (MESA) to understand the variations in the properties, such as specific heat (<span>\\(C_P\\)</span>) and degeneracy parameter (<span>\\(\\eta \\)</span>). The profile of specific heat shows a discontinuity and that of the degeneracy parameter shows a dip near the ignition region. As expected, the size of WD decreases and <i>g</i> increases during the accretion. However, a red-giant-like expansion is observed after the rapid ignition towards the end. Our study explains the reason behind the delay in onset of helium ignition due to the difference in carbon abundance in a CO-WD. We found that WDs of the lower abundance of carbon, accrete slightly longer before the onset of helium ignition.</p></div>","PeriodicalId":610,"journal":{"name":"Journal of Astrophysics and Astronomy","volume":null,"pages":null},"PeriodicalIF":1.1000,"publicationDate":"2023-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Accreting white dwarfs: effect of WD composition on helium ignition during slow accretion\",\"authors\":\"Harish Kumar, Abhinav Gupta, Siddharth Savyasachi Malu, Shashikant Gupta\",\"doi\":\"10.1007/s12036-023-09931-1\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Understanding the explosion mechanism of type Ia supernova is among the most challenging issues in astrophysics. Accretion of matter on a carbon–oxygen (CO) white dwarf (WD) from a companion star is one of the most important keys in this regard. Our aim is to study the effects of WD composition on various parameters during the accretion of helium-rich matter at a slow rate. We have used the computer simulation code Modules for Experiments in Stellar Astrophysics (MESA) to understand the variations in the properties, such as specific heat (<span>\\\\(C_P\\\\)</span>) and degeneracy parameter (<span>\\\\(\\\\eta \\\\)</span>). The profile of specific heat shows a discontinuity and that of the degeneracy parameter shows a dip near the ignition region. As expected, the size of WD decreases and <i>g</i> increases during the accretion. However, a red-giant-like expansion is observed after the rapid ignition towards the end. Our study explains the reason behind the delay in onset of helium ignition due to the difference in carbon abundance in a CO-WD. We found that WDs of the lower abundance of carbon, accrete slightly longer before the onset of helium ignition.</p></div>\",\"PeriodicalId\":610,\"journal\":{\"name\":\"Journal of Astrophysics and Astronomy\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.1000,\"publicationDate\":\"2023-04-20\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Astrophysics and Astronomy\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://link.springer.com/article/10.1007/s12036-023-09931-1\",\"RegionNum\":4,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"ASTRONOMY & ASTROPHYSICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Astrophysics and Astronomy","FirstCategoryId":"101","ListUrlMain":"https://link.springer.com/article/10.1007/s12036-023-09931-1","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ASTRONOMY & ASTROPHYSICS","Score":null,"Total":0}
Accreting white dwarfs: effect of WD composition on helium ignition during slow accretion
Understanding the explosion mechanism of type Ia supernova is among the most challenging issues in astrophysics. Accretion of matter on a carbon–oxygen (CO) white dwarf (WD) from a companion star is one of the most important keys in this regard. Our aim is to study the effects of WD composition on various parameters during the accretion of helium-rich matter at a slow rate. We have used the computer simulation code Modules for Experiments in Stellar Astrophysics (MESA) to understand the variations in the properties, such as specific heat (\(C_P\)) and degeneracy parameter (\(\eta \)). The profile of specific heat shows a discontinuity and that of the degeneracy parameter shows a dip near the ignition region. As expected, the size of WD decreases and g increases during the accretion. However, a red-giant-like expansion is observed after the rapid ignition towards the end. Our study explains the reason behind the delay in onset of helium ignition due to the difference in carbon abundance in a CO-WD. We found that WDs of the lower abundance of carbon, accrete slightly longer before the onset of helium ignition.
期刊介绍:
The journal publishes original research papers on all aspects of astrophysics and astronomy, including instrumentation, laboratory astrophysics, and cosmology. Critical reviews of topical fields are also published.
Articles submitted as letters will be considered.