The extremely accurate estimates of stellar variability and radial velocity in the Gaia Data Release 3(Gaia DR3)have enabled us to examine the close binarity and radial velocity(RV)of central stars(CSs)of planetary ne...The extremely accurate estimates of stellar variability and radial velocity in the Gaia Data Release 3(Gaia DR3)have enabled us to examine the close binarity and radial velocity(RV)of central stars(CSs)of planetary nebulae(PNe).This study is twofold:(1)searching for new close binary CS candidates to better understand how binarity affects the formation and evolution of PNe;and(2)extending the sample size of known RVs of PNe in order to understand their kinematics and the dynamics of the Milky Way.As a target sample,we used all true,possible,and likely PNe available in the literature.Then,we looked for their matched Gaia DR3 sources that provide measurements of variability and RV.As a result,we detected the first large collection of trustworthy photometric variability of 26 symbiotic stars and 82 CSs.In this CS group,there are 24 sources already classified as true close binary CSs in the literature.Hence,we discovered 58 new close binary CS candidates.This close binary(CB)sample represents more than half of what is currently available in the literature.In addition,we identified the radial velocities for 51 PNe.To our knowledge,24 of these were measured for the first time.The RV measurements predicted by Gaia,based on the Doppler shift of the CS absorption lines,and those derived from nebular emission lines,show satisfactory agreement except for a few extremely high-velocity PNe.展开更多
The present work aims to build a new statistical distance scale for planetary nebulae(PNe)based on a rigorous calibration sample.The distances of the calibration sample are derived from the trigonometric parallax meth...The present work aims to build a new statistical distance scale for planetary nebulae(PNe)based on a rigorous calibration sample.The distances of the calibration sample are derived from the trigonometric parallax method using the recent measurements of Gaia Early Data Release 3(Gaia EDR3).The new distance scale is created by applying the well-known linear relationship between the radio surface brightness temperature and the nebular radius.The calibration sample is made up of 96 PNe of accurately computed distances with uncertainties less than20%.Earlier ground-and space-based trigonometric parallaxes of PNe display inconsistency with those of Gaia,particularly the Hipparcos results.In addition,these measurements have appreciably lower precision than those of Gaia.When compared to the trigonometric technique,the expansion and kinematic methods exhibited more consistency than the spectroscopic,extinction,gravity,and photoionization methods.Furthermore,contrary to earlier results in the literature,the extinction and gravity methods,on average,underestimate and slightly overestimate the PN distances respectively.As a byproduct of extracting the Gaia parallaxes,we detect the radial velocity and variability for 14 and 3 PN central stars(CSs),respectively.To our knowledge,the variability of Hen 2-447 CS has been determined for the first time.展开更多
文摘The extremely accurate estimates of stellar variability and radial velocity in the Gaia Data Release 3(Gaia DR3)have enabled us to examine the close binarity and radial velocity(RV)of central stars(CSs)of planetary nebulae(PNe).This study is twofold:(1)searching for new close binary CS candidates to better understand how binarity affects the formation and evolution of PNe;and(2)extending the sample size of known RVs of PNe in order to understand their kinematics and the dynamics of the Milky Way.As a target sample,we used all true,possible,and likely PNe available in the literature.Then,we looked for their matched Gaia DR3 sources that provide measurements of variability and RV.As a result,we detected the first large collection of trustworthy photometric variability of 26 symbiotic stars and 82 CSs.In this CS group,there are 24 sources already classified as true close binary CSs in the literature.Hence,we discovered 58 new close binary CS candidates.This close binary(CB)sample represents more than half of what is currently available in the literature.In addition,we identified the radial velocities for 51 PNe.To our knowledge,24 of these were measured for the first time.The RV measurements predicted by Gaia,based on the Doppler shift of the CS absorption lines,and those derived from nebular emission lines,show satisfactory agreement except for a few extremely high-velocity PNe.
文摘The present work aims to build a new statistical distance scale for planetary nebulae(PNe)based on a rigorous calibration sample.The distances of the calibration sample are derived from the trigonometric parallax method using the recent measurements of Gaia Early Data Release 3(Gaia EDR3).The new distance scale is created by applying the well-known linear relationship between the radio surface brightness temperature and the nebular radius.The calibration sample is made up of 96 PNe of accurately computed distances with uncertainties less than20%.Earlier ground-and space-based trigonometric parallaxes of PNe display inconsistency with those of Gaia,particularly the Hipparcos results.In addition,these measurements have appreciably lower precision than those of Gaia.When compared to the trigonometric technique,the expansion and kinematic methods exhibited more consistency than the spectroscopic,extinction,gravity,and photoionization methods.Furthermore,contrary to earlier results in the literature,the extinction and gravity methods,on average,underestimate and slightly overestimate the PN distances respectively.As a byproduct of extracting the Gaia parallaxes,we detect the radial velocity and variability for 14 and 3 PN central stars(CSs),respectively.To our knowledge,the variability of Hen 2-447 CS has been determined for the first time.
