论文标题

“长颈鹿”:与$ {\ sim} 2〜m_ \ odot $ low low low low low giant的二进制中的剥离红色巨人发现

The "Giraffe": Discovery of a stripped red giant in an interacting binary with a ${\sim}2~M_\odot$ lower giant

论文作者

Jayasinghe, T., Thompson, Todd A., Kochanek, C. S., Stanek, K. Z., Rowan, D. M., Martin, D. V., El-Badry, Kareem, Vallely, P. J., Hinkle, J. T., Huber, D., Isaacson, H., Tayar, J., Auchettl, K., Ilyin, I., Howard, A. W., Badenes, C.

论文摘要

我们报告了剥离的巨型 +下部巨型二进制的发现,2M04123153 + 6738486(2M0412),在搜索非相互作用的紧凑型对象巨星二进制文件中确定。 2M0412是进化的($ t _ {\ rm eff,giant} \ simeq4000 $ k),发光($ l _ {\ rm giant} \ simeq150〜l_ \ odot $)圆形$ p = 81.2 $ day binary binary binary by biarn。 2M0412是先前被归类为半定期变量的已知变量恒星。随访Keck/Hires和LBT/PEPSI光谱的互相关函数显示出具有隐含质量比的RV变量第二个成分$ Q = M _ {\ RM Giant}/M _ {\ rm comp} \ rm comp} \ simeq0.20.20 \ pm0.01 $。 ASAS-SN,ATLA,TESS和ZTF光曲线表明,巨人是Roche Lobe填充椭圆形变量,倾斜$ 49.4^\ Circ {} \ PM {0.3^{\ circ}} $ $ _ {\ m_ _ { $ \ simeq3.7 $ kpc。巨人的质量表明其信封已被剥离。下红色巨型分支的巨型同伴的质量为$ m _ {\ rm comp} = 1.91 \ pm0.03〜m_ \ odot $,$ t _ {\ rm eff,comp} \ simeq5000 $ k,$ l _ { comp} \ simeq11〜r_ \ odot $。我们还确定了一个轨道相依赖的,宽阔的$ \ rmHα$排放线,这可能表明从剥离的红色巨人持续积聚到同伴。

We report the discovery of a stripped giant + lower giant binary, 2M04123153+6738486 (2M0412), identified during a search for non-interacting compact object-star binaries. 2M0412 is an evolved ($T_{\rm eff, giant}\simeq4000$ K), luminous ($L_{\rm giant}\simeq150~L_\odot$) red giant in a circular $P=81.2$ day binary. 2M0412 is a known variable star previously classified as a semi-regular variable. The cross-correlation functions of follow-up Keck/HIRES and LBT/PEPSI spectra show an RV-variable second component with implied mass ratio $q=M_{\rm giant}/M_{\rm comp}\simeq0.20\pm0.01$. The ASAS-SN, ATLAS, TESS and ZTF light curves show that the giant is a Roche lobe filling ellipsoidal variable with an inclination of $49.4^\circ{}\pm{0.3^{\circ}}$, and a giant mass of $M_{\rm giant}=0.38\pm0.01~ M_\odot$ for a distance of $\simeq3.7$ kpc. The mass of the giant indicates that its envelope has been stripped. The giant companion on the lower red giant branch has a mass of $M_{\rm comp}=1.91\pm0.03~M_\odot$ with $T_{\rm eff, comp}\simeq5000$ K, $L_{\rm comp}\simeq60~L_\odot$ and $R_{\rm comp}\simeq11~R_\odot$. We also identify an orbital phase dependent, broad $\rm Hα$ emission line which could indicate ongoing accretion from the stripped red giant onto the companion.

扫码加入交流群

加入微信交流群

微信交流群二维码

扫码加入学术交流群,获取更多资源