Comment on "A non-interacting low-mass black hole -- giant star binary system"

Response to Comment on "A Non-Interacting Low-Mass Black Hole -- Giant Star Binary System"

van den Heuvel & Tauris argue that if the red giant star in the system 2MASS J05215658+4359220 has a mass of 1 solar mass (M$_\odot$), then its unseen companion could be a binary composed of two 0.9 M$_\odot$ stars, making a triple system. We contend that the existing data are most consistent with a giant of mass $3.2^{+1.0}_{-1.0}$ M$_\odot$, implying a black hole companion of $3.3^{+2.8}_{-0.7}$ M$_\odot$.

LMC中的偏心椭球红巨星双星：轨道完全解和近星点相互作用的讨论

Eccentric Ellipsoidal Red Giant Binaries in the LMC: Complete Orbital Solutions and Comments on Interaction at Periastron

利用已知距离的椭球变星模型，即使在没有日食的情况下，也可以精确地确定两个组成部分的质量。我们提出这样的建模使用光和径向速度曲线的椭球红巨星双星在大麦哲伦星云，在那里他们也被称为序列E星。根据光变曲线的形状，恒星被选为可能的偏心系统。我们已经证实了他们的偏心性质，并获得了系统参数使用威尔逊Devinney代码。在我们的样本中，大多数恒星都表现出不等的光极大值和极小值，这是在具有圆形轨道的序列E变星中没有观察到的现象。我们发现的证据表明，红巨星的形状在整个轨道上的变化，由于高偏心率和不同的影响的同伴。在其中两颗红巨星中可以明显看到短暂的脉动。我们确定脉动模式和评论他们的位置在周期光度平面。定义这些系统的参数铺平了道路的建模，以确定由什么机制偏心率保持在进化的二进制文件。

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

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,…

红巨星的3D大气模型

3D Model Atmospheres of Red Giant Stars

我们提供了一个简要的概述与3D辐射流体动力学代码CO5BOLD的红巨星大气的建模。我们强调的方面，3D建模提供了额外的洞察力超出标准的流体静力学1D模型，并评论目前的建模挑战。

A Unicorn in Monoceros: the $3M_\odot$ dark companion to the bright, nearby red giant V723 Mon is a non-interacting, mass-gap black hole candidate

We report the discovery of the closest known black hole candidate as a binary companion to V723 Mon. V723 Mon is a nearby ($d\sim460\,\rm pc$), bright ($V\simeq8.3$~mag), evolved ($T_{\rm eff, giant}\simeq4440$~K, and $L_{\rm giant}\simeq173~L_\odot$) red giant in a high mass function, $f(M)=1.72\pm 0.01~M_\odot$, nearly circular binary ($P=59.9$ d, $e\simeq 0$). V723 Mon is a known variable star, previously classified as an eclipsing binary, but its All-Sky Automated Survey (ASAS), Kilodegree Extremely Little Telescope (KELT), and Transiting Exoplanet Survey Satellite (TESS) light curves are …

主序前双星系统中巨大相互作用日冕流的证据

Evidence for giant interacting coronal streamers in a pre-main-sequence binary system

在这里，我们报告的VLBI发现的类太阳扩展流光锚定在两个弱线T金牛星的双星系统V773 Tau A。覆盖双星间距离的20个恒星半径延伸流光进入碰撞在每一个恒星旋转与随之发生的磁重联。被限制在流中的热电子被加速到相对论速度，并在无线电波段发射同步辐射，使磁流在VLBI图像中“可见”。这与太阳的情况不同，在太阳的情况下，来自流光的发射只是散射的光球光，在遥远的物体中永远无法观察到。金牛座T恒星中延伸的类太阳流光的证据，被认为是完全对流的，或几乎完全对流的物体，表明速斜层，在这种情况下，要么根本不存在，要么埋得很深，与这种太阳般的磁性结构的形成无关。