摘要
Accurate radial velocity determinations of optical emission lines(i.e.,[NⅡ]λλ6548,6584,Hαand[SⅡ]λλ6717,6731)are very important for investigating the kinematic and dynamic properties of nebulae.The second stage survey program of Large sky Area Multi-Object fiber Spectroscopic Telescope(LAMOST)has started a sub-survey of nebulae(MRS-N)which will spectroscopically observe the optical emission lines of a large sample of nebulae near the Galactic plane.Until now,15 MRS-N plates have been observed from September 2017 to June 2019.Based on fitting the sky emission lines in the red band spectra of MRS-N,we investigate the precision of wavelength calibration and find there are systematic deviations of radial velocities(RVs)from~0.2 to 4 km s^(-1) for different plates.Especially for the plates obtained in March 2018,the systematic deviations of RVs can be as large as~4 km s^(-1),which then go down to~0.2-0.5 kms^(-1) at the end of 2018 and January 2019.An RV calibration function is proposed for these MRS-N plates,which can simultaneously and successfully calibrate the systematic deviations and improve the precision of RVs.
基金
supported by the National Key R&D Program of China(Grant No.2017YFA0402704)
the National Natural Science Foundation of China(Grant Nos.11903048,12090041,12090040,11833006,12073051,11733006,11403061,U1531118,11973060,U1631131 and 11873057)
the NAOC Nebula Talents Program and the Key Research Program of Frontier Sciences,CAS(Grant No.QYZDYSSW-SLH007)
supports from The Science and Technology Development Fund,Macao SAR(file No.061/2017/A2 and 0007/2019/A)
Faculty Research Grants of the Macao University of Science and Technology(program No.FRG-19-004-SSI)
Guoshoujing Telescope(the Large Sky Area MultiObject Fiber Spectroscopic Telescope,LAMOST)is a National Major Scientific Project built by the Chinese Academy of Sciences
Funding for the project has been provided by the National Development and Reform Commission。
