最近X射线观测共生星AG钉：他们意味着碰撞恒星风？

The H$α$ and H$β$ Raman-scattering line profiles of the symbiotic star AG Peg

The H$α$ and H$β$ line profiles of the symbiotic star AG Peg observed on 1998 September (phase $ϕ$ = 10.24), display the top narrow double Gaussian and bottom broad (FWHM of 200 -- 400 kms$^{-1}$) components. The photo-ionization model indicated that the ionized zone, responsible for the hydrogen Balmer and Lyman lines, is radiation-bounded, with a hydrogen gas number density of $n_{\rm H} \sim 10^{9.85}$ cm$^{-3}$ and a gas temperature of T$_e$ = 12\,000 -- 15\,000~K. We carried out Monte Carlo simulations to fit the Raman scattering broad wings, assuming that the hydrogen Ly$β$ and Ly$γ$ lin…

Detection of optical flickering from the symbiotic Mira-type binary star EF Aquilae

We performed photometry with a 1 minute time resolution of the symbiotic stars EF Aquilae, AG Pegasi and SU Lyncis in Johnson B and V band. Our observations of the symbiotic Mira-type star EF Aql demonstrate the presence of stochastic light variations with an amplitude of about 0.25 magnitudes on a time scale of 5 minutes. The observations prove the white dwarf nature of the hot component in the binary system. It is the 11th symbiotic star (among more than 200 symbiotic stars known in our Galaxy) which displays optical flickering. For SU Lyn we do not detect flickering with an amplitude above …

共生新星AG Peg在165年后的新爆发

New outburst of the symbiotic nova AG Peg after 165 years

AG Peg被称为最慢的共生新星，它在1850年左右经历了类似新星的爆发。在165年后的2015年6月，它再次爆发，表现出Z和型爆发的特征。主要目标是确定2015年AG Peg爆发的基本特征，性质和类型。我们通过使用低分辨率光谱学（330-750 nm）、中分辨率光谱学（420-720 nm; R=11000）和$UBVR_{\rm C}I_{\rm C}$光度学对2015年爆发的光谱能量分布进行建模来实现这一目标。光学观测与档案HST和FUSE光谱从前面的平静补充。在爆发期间，热分量的光度范围为2-11 $\times 10^{37}(d/0.8{\rm kpc})^2$ erg/s。为了产生最大的光度，白矮星（WD）必须在$\sim 3\times 10^{-7}$ M $_{\odot}yr^{-1}$处吸积，这超过了稳定燃烧的极限，从而导致从WD吹出光学厚风。我们确定了它的质量损失率为几个$\times 10^{-6}$ M $_{\odot}yr^{-1}$。在电离源$1.5-2.3\times 10^5$ K的高温下，风将WD的一部分光球辐射转化为星云辐射，占光学辐射的主导地位。一个数量级的增加排放措施，从几个$\times 10^{59}(d/0.8 {\rm kpc})^2$厘米$^{-3}$在平静期间，到几个$\times 10^{60}(d/0.8\,{\rm …

共生双星研究中应注意的问题V.由UBV星等导出的物理参数

Notices to investigation of symbiotic binaries V. Physical parameters derived from UBV magnitudes

在光学上，共生双星的光谱由冷巨星、共生星云和热恒星的贡献组成。强发射线叠加在连续谱上。在本文中，我们介绍了一种简单的方法来提取各个分量的辐射光度UBV的大小。我们将该方法应用于经典的共生星AX Per，AG Dra，AG Peg和Z And，共生新星RR Tel和V1016 Cyg以及经典新星V1974 Cyg在其星云阶段。我们估算了这些系统中星云的电子温度和辐射量，以及共生天体中巨星的V星等。我们的结果是在一个很好的协议与那些独立获得的宝贵的模拟紫外-红外SED。

共生星XIII的近期测光

Recent photometry of symbiotic stars - XIII

我们提出了新的多色（UBVRcIc）光度观测的经典共生星，EG和，Z和，BF Cyg，CH Cyg，CI Cyg，V1329 Cyg，TX CVn，AG Dra，Draco C1，AG Peg和AX Per，在2007.1和2011.9之间进行。本文的目的是提出新的数据，我们的监测计划，描述其光变曲线的主要特点，并指出问题，为他们今后的调查。采用经典的光电测光法和CCD测光法获得数据。

Spectroscopic and photometric analysis of symbiotic candidates -- I. Ten candidates on classical symbiotic stars

Symbiotic stars belong to a group of interacting binaries that display a wide variety of phenomena, including prominent outbursts connected with mass transfer, as well as stellar winds, jets, eclipses, or intrinsic variability of the components. Dozens of new symbiotic stars and candidates have been discovered in recent years. However, there are many objects which are still poorly studied. Some symbiotic candidates suspected in the literature have never been studied spectroscopically. In this contribution, we present the first results of the ongoing campaign focused on symbiotic candidates. In…

The hidden symbiotic star SU Lyn -- detection of flickering in U band

We report photometric observations of the hidden symbiotic star SU Lyn in the optical bands. In five nights we detect a weak flickering in U band with amplitude of about 0.05 magnitudes. No intranight variations are found in B, V, g' and r' bands. This is one more indication that the secondary component is a white dwarf accreting at low accretion rate. We also searched for intranight variability of a dozen related object (RR Boo, RT Boo, AM Cyg, AG Peg, BF Cyg, NQ Gem, StHa190, V627 Cas, XX Oph, FS Cet and Y Gem) in which no variability above the observational errors is detected.

Photometry of Symbiotic Stars - XIV

We present new multicolour UBVRcIc photometric observations of symbiotic stars, EG And, Z And, BF Cyg, CH Cyg, CI Cyg, V1016 Cyg, V1329 Cyg, AG Dra, RS Oph, AG Peg, AX Per, and the newly discovered (August 2018) symbiotic star HBHA 1704-05, we carried out during the period from 2011.9 to 2018.75. Historical photographic and visual/V data were collected for HBHA 1704-05, FG Ser and AE Ara, AR Pav, respectively. The main aim of this paper is to present our original observations of symbiotic stars and to describe the most interesting features of their light curves. For example, periodic variation…

用干涉测量重新审视共生双星。I. PIONIER档案汇编

Revisiting symbiotic binaries with interferometry. I. The PIONIER archival collection

本文利用VLTI/PIONIER干涉测量数据和Gaia距离重新分析六颗共生星，发现其红巨星均位于洛希瓣内，支持恒星风主导质量转移，并推断这些巨星可能处于渐近巨星支。

质量转移红巨星的Roche瓣填充因子--PIONIER观点

Roche-lobe filling factor of mass-transferring red giants - the PIONIER view

使用PIONIER访客仪器，结合了ESO甚大望远镜干涉仪的四个辅助望远镜的光线，我们精确测量了几个共生和相关恒星的直径：HD 352，HD 190658，V1261 Ori，ER Del，FG Ser和AG Peg。这些直径-在0.6到2.3毫弧秒的范围内-被用来评估质量损失巨星的洛希瓣的填充因子，并提供正在进行的质量转移的性质的指示。我们还提供了第一个光谱轨道的ER德尔，根据CORAVEL和HERMES/墨卡托观测。发现该系统有一个周期为5.7年的偏心轨道。在共生星FG Ser的情况下，我们发现直径在41天的过程中变化了13%，而HD 352的观测结果表明它在伸长。这两颗恒星的罗氏填充因子都接近于1，HD 190658也很可能是这种情况，而其他三颗恒星的罗氏填充因子都低于0.5-0.6。我们的观测揭示了干涉测量在研究相互作用的双星中的作用--我们结论中的主要限制是对物体的距离知之甚少。