The Hertzsprung–Russell diagram (HRD) is fully examined using the Fourier analysis. This work shows more stars are above the gap in the lower main sequence than below it, and this implies that stars spend more time above the gap while they undergo variability associated with the 3 He instability. The enhanced HRD also shows the width of the gap is not linear and depends on the ##IMG## [http://ej.iop.org/images/1538-3881/160/3/102/ajaba192ieqn1.gif] {${G}_{\mathrm{BP}}-{G}_{\mathrm{RP}}$} color up until ##IMG## [http://ej.iop.org/images/1538-3881/160/3/102/ajaba192ieqn2.gif] {${G}_{\mathrm{BP}}-{G}_{\mathrm{RP}}=2.7$} . Beyond this color limit, the gap is hardly seen. Besides, a new low density region is revealed for the first time centered at M G ≈ 10.7 and GBP − G RP ≈ 2.8, which is below the lower right corner of the gap. This work also shows that the main seque...

中文翻译：

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Gaia Data Release 2揭示了主要序列中的精细结构

使用傅立叶分析对Hertzsprung–Russell图（HRD）进行了全面检查。这项工作表明，在较低的主序中，处于间隙上方的恒星比位于其下方的恒星多，这意味着恒星在间隙上方花费更多的时间，同时它们经历与3 He不稳定性相关的变化。增强的HRD还显示出间隙的宽度不是线性的，并且取决于## IMG ## [http://ej.iop.org/images/1538-3881/160/3/102/ajaba192ieqn1.gif] { $ {G} _ {\ mathrm {BP}}-{G} _ {\ mathrm {RP}} $}变色直到## IMG ## [http://ej.iop.org/images/1538-3881 /160/3/102/ajaba192ieqn2.gif] {$ {G} _ {\ mathrm {BP}}-{G} _ {\ mathrm {RP}} = 2.7 $}。超过此颜色限制，几乎看不到间隙。此外，首次发现了一个新的低密度区域，其中心位于MG≈10.7和GBP-G RP≈2.8，位于间隙的右下角以下。