Peculiar Red Nova V838 Mon: Accretion and Interaction in a Wide Binary System after Explosion of Its Companion
Vitaly Goranskij, Alla Zharova, Elena Barsukova, Sergei Fabrika, Azamat Valeev
备注:
7 pages, 5 figures, contributed paper to Conference "Interacting Binaries: Accretion and Synchronization" held in Crimean Astrophysical Observatory (Ukraine) on June 20-26, 2008
We report the results of recent multicolor photometry and medium resolution spectroscopy of V838 Mon taken in 2007-2008. In the eclipse-like event in December 2006, the hot B3V type companion disappeared. The event accompanied by strengthening emission [FeII]/FeII lines in the spectra. We explain this event as the formation of temporal short-lived accretion disc around the hot companion. Later, in February 2007 the hot star reappeared in its full brightness, but disappeared again for a long time since September 2007. This is the engulf of B3V companion by expanding remnant of 2002 outburst. We assume that the thick accretion disc has formed around B type companion which is moving now inside the envelope of the cool star. There is some evidence of heating this disc and/or cool star envelope. We estimated the radius of expanding cool remnant in December, 2006 of about 150 A.U. or 30000 solar radii.
How peculiar is the "peculiar variable" DZ Crucis (Nova Cru 2003)?
变星DZ Cru在2003年8月的爆发中被发现时被认为是一颗新星。然而,这一解释后来受到了挑战,当该物体的第一个光谱被报道时。我们目前的近红外光谱的DZ克鲁获得的新技术望远镜在3个场合,开始1.5年后爆发,目的是建立对象的性质。光谱显示H I,O I,[N I]发射线,以及叠加在尘埃连续谱上的He I P Cygni线。这些观测结果表明,“十字星上的奇特变星”是一颗经典新星。
The Presence of Accretion Disks in Novae Shortly After their Outbursts
在几乎没有理论依据的情况下,人们相信吸积盘(AD)在新星爆发中被摧毁,并且仅在几十年后恢复。在我的论文中,我试图找到年轻新星中AD存在的观测特征。我将讨论两种情况:1。1992年天鹅座新星V1974-我们在新星爆发后大约2.5年发现了永久性的超级驼峰。这是一个非常强有力的证据,根据磁盘不稳定性模型的存在。2. Nova V1425 Aql 1995年-在发现后约15个月发现了中间极系统的光度特征。最有可能的是,通过AD来维持吸积。
CK Vul (Nova Vul 1670) is one of the most mysterious objects among erupting stellar objects. Past studies have suggested that CK Vul is a final helium-flash object resembling V605 Aql and V4334 Sgr (Sakurai's object). The peculiar outburst light curve of CK Vul, however, had no similar counterpart among the known eruptive objects. Furthermore, the presence of hydrogen in the proposed remnant seems to contradict with the final helium-flash scenario. We propose that the peculiarities of CK Vul can be naturally understood if we consider a merging of main-sequence stars, following a new interpreta…
A solution to the transition phase in classical novae
在发现新星GK Per 1901的光学光变曲线中的准周期振荡一个世纪之后,新星种群中某一部分的过渡阶段的原因仍然未知。三年前,我们提出了一个解决这个问题的方案,并提出了过渡阶段和中间极(IP)之间的可能联系。大约10%的激变变星被归类为IP,这与新星过渡阶段的罕见性(约15%)一致。最近对三颗新星的观测似乎支持了我们的预测。这种联系解释如下:新星爆发只在IP中破坏吸积盘。在爆发后的几个星期到几个月,圆盘的恢复引起强风,阻挡了来自白矮星的辐射,因此尘埃没有被破坏。如果风很强,就像DQ Her的情况一样(也许是因为它的旋转周期很短),这会导致尘埃最少。
High speed photometry of faint Cataclysmic Variables: IV. V356 Aql, Aqr1, FIRST J1023+0038, Ha 0242-2802, GI Mon, AO Oct, V972 Oph, SDSS 0155+00, SDSS 0233+00, SDSS 1240-01, SDSS 1556-00, SDSS 2050-05, FH Ser