Eight Years of Light from ASASSN-15oi: Towards Understanding the Late-time Evolution of TDEs
A. Hajela, K. D. Alexander, R. Margutti, R. Chornock, M. Bietenholz, C. T. Christy, M. Stroh, G. Terreran, R. Saxton, S. Komossa, J. S. Bright, E. Ramirez-Ruiz,… 展开作者
A. Hajela, K. D. Alexander, R. Margutti, R. Chornock, M. Bietenholz, C. T. Christy, M. Stroh, G. Terreran, R. Saxton, S. Komossa, J. S. Bright, E. Ramirez-Ruiz, D. L. Coppejans, J. K. Leung, Y. Cendes, E. Wiston, T. Laskar, A. Horesh, G. Schroeder, Nayana A. J., M. H. Wieringa, N. Velez, E. Berger, P. K. Blanchard, T. Eftekhari, S. Gomez, M. Nicholl, H. Sears, B. A. Zauderer
We present the results from an extensive follow-up campaign of the Tidal Disruption Event (TDE) ASASSN-15oi spanning $δt \sim 10 - 3000$ d, offering an unprecedented window into the multiwavelength properties of a TDE during its first $\approx 8$ years of evolution. ASASSN-15oi is one of the few TDEs with strong detections at X-ray, optical/UV, and radio wavelengths and featured two delayed radio flares at $δt \sim 180$ d and $δt \sim 1400$ d. Our observations at $> 1400$ d reveal an absence of thermal X-rays, a late-time variability in the non-thermal X-ray emission, and sharp declines in the non-thermal X-ray and radio emission at $δt \sim 2800$ d and $\sim 3000$ d, respectively. The UV emission shows no significant evolution at $>400$ d and remains above the pre-TDE level. We show that a cooling envelope model can explain the thermal emission consistently across all epochs. We also find that a scenario involving episodic ejection of material due to stream-stream collisions is conducive to explaining the first radio flare. Given the peculiar spectral and temporal evolution of the late-time emission, however, constraining the origins of the second radio flare and the non-thermal X-rays remains challenging. Our study underscores the critical role of long-term, multiwavelength follow-up.
Discovery of an outflow from radio observations of the tidal disruption event ASASSN-14li
我们报告发现了附近光学发现的TDE ASASSN-14 li(距离90 Mpc)的瞬时射电发射,使其成为射电中检测到的第一个典型TDE,并明确指出形成了动能为$\approx (4-10)\times10^{47}$ erg、速度为$\approx 12,000-36,000$ km s $^{-1}$的非相对论外流,质量为$\approx 3\times10^{-5}-7\times10^{-4}$ M $_{\odot}$。我们发现,流出物是在2014年8月11日至25日喷出的,与基于光学,紫外和X射线观测的超爱丁顿吸积时间的独立估计一致,并且喷出的质量相当于超爱丁顿阶段吸积质量的约$1-10\%$。射电辐射的时间演化也揭示了环核密度分布,$ρ(R)\propto R^{-2.5}$的尺度约为0.01 pc,即使在最近的SMBH中也无法通过直接测量来探测。我们发现的无线电发射从最近的研究TDE到目前为止,无线电光度低于所有以前的限制,表明非相对论外流是无处不在的TDE,未来,更敏感,无线电调查将发现类似的事件。
Radio emission of tidal disruption events from wind-cloud interaction
风可以在潮汐中断事件(TDE)中启动。有人提出,风可以与黑洞周围的云相互作用,产生弓形激波,加速电子,并产生无线电发射。我们重新研究了风云相互作用模式。我们采用的超爱丁顿循环吸积流在TDEs的辐射流体动力学模拟发现的风的属性。利用TDEs的风云相互作用模型,我们可以计算出射电峰值发射频率、峰值频率处的亮度及其随时间的演化。我们发现,该模型预测的射电峰值发射频率,在峰值频率的光度,以及它们的时间演变可以很好地与TDEs AT 2019 dsg和ASASSN-14 li的一致。这表明,在这两个无线电TDE,风-云相互作用机制可能是负责无线电发射。
Light curves of time-dependent accretion disk in tidal disruption events
National Astronomical Observatories, Chinese Academy of Sciences(中国科学院国家天文台);School of Astronomy and Space Sciences, University of Chinese Academy of Sciences(中国科学院大学天文与空间科学学院)
Interpreting the diversity of afterglow emission from radio-detected tidal disruption events with instantaneous and delayed outflows
Astronomical Institute, Graduate School of Science, Tohoku University(东北大学理学研究科天文学研究所);University of Wisconsin, Madison(威斯康星大学麦迪逊分校);Indian Institute of Technology Indore(印度理工学院印多尔分校);University of Nevada, Las Vegas(内华达大学拉斯维加斯分校);California Polytechnic State University(加州州立理工大学);Naropa University(纳洛帕大学);The Pennsylvania State University(宾夕法尼亚州立大学);Kyoto University(京都大学)
Triple radio flares from tidal disruption events: jet-wind collisions and the discovery of a third radio flare from AT2020vwl
School of Natural Sciences, Institute for Advanced Study(普林斯顿高等研究院自然科学学院);International Centre for Radio Astronomy Research – Curtin University(西澳大学国际射电天文研究中心);Department of Astronomy/Steward Observatory(天文学系/斯图尔德天文台)
A Disappearing Act: Constraints From "Missing" Flares of Repeating Partial TDE Candidates
University of Illinois Urbana-Champaign(伊利诺伊大学厄巴纳-香槟分校);NSF-Simons AI Institute for the Sky (SkAI)(美国国家科学基金会西蒙斯天空人工智能研究所);Northwestern University(西北大学);Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA)(天体物理学跨学科探索与研究中心);Institute for Advanced Study in Physics, Zhejiang University(浙江大学高等物理研究院);Institute for Astronomy, School of Physics, Zhejiang University(浙江大学物理学院天体物理研究所)
eROSITA-RU Tidal Disruption Events with Keck-I/LRIS: Sample Selection, Optical Properties, and Host Galaxy Demographics
University of California, Berkeley(加州大学伯克利分校);Sichuan University(四川大学);Miller Institute for Basic Research in Science(米勒基础科学研究学院);Berkeley Center for Multi-messenger Research on Astrophysical Transients and Outreach (Multi-RAPTOR)(伯克利多信使天体物理瞬变现象研究与外展中心(Multi-RAPTOR));Space Research Institute (IKI), Russian Academy of Sciences(俄罗斯科学院空间研究所);Max-Planck-Institut für Astrophysik(马克斯·普朗克天体物理学研究所)
The Tidal Disruption Event AT 2018hyz II: Light Curve Modeling of a Partially Disrupted Star
AT 2018 hyz(=ASASSN-18 zj)是一个位于静止E+A星系核心的潮汐破裂事件(TDE),红移为$z = 0.04573$,首次由全天超新星自动巡天(ASAS-SN)发现。我们提出了瞬态的光学+UV测光,以及X射线光谱和无线电上限。AT 2018 hyz的辐射热光变曲线与其他已知的TDE相当,并且在早期以与$t^{-5/3}$一致的速率下降,发射出$E = 9\times10^{50}$ erg的总辐射能量。在辐射热峰值后约50天,紫外光曲线出现一个过度的凸起,然后在250天后出现一个平坦化。光变曲线显示,在辐射热峰值之后约50天,紫外线中出现了一个过度的凸起,持续了至少100天,这可能与外流有关。我们探测到一个持续存在至少86天的X射线源。X射线光谱显示总未吸收通量为$\sim 4\times10^{-14}$ erg cm $^{-2}$ s $^{-1}$,并且最佳拟合为黑体加幂律模型,光子指数为$Γ= 0.8$。热X射线模型无法解释光子$> 1$ keV,而无线电非探测有利于逆康普顿散射,而不是非热分量的射流。我们使用模块化的开放源滤波器瞬态(MOSFiT)的光学和紫外光曲线模型,并找到一个最适合的黑洞的$5.2\times10^6$ M $_\odot$部分破坏$0.1$ M $_\odot$明星(剥离质量$\sim 0.01$ M $_\odot$推断的…
A Time-Dependent Solution for GSN 069 Disk Evolution and the Nature of Long-Lived Tidal Disruption Events
Johns Hopkins University(约翰斯·霍普金斯大学);Newcastle University(纽卡斯尔大学);Space Telescope Science Institute(太空望远镜科学研究所);California Institute of Technology(加州理工学院)