SN 2023zaw: the low-energy explosion of an ultra-stripped star
T. Moore, J. H. Gillanders, M. Nicholl, M. E. Huber, S. J. Smartt, S. Srivastav, H. F. Stevance, T. -W. Chen, K. C. Chambers, J. P. Anderson, M. D. Fulton, S. R… 展开作者
T. Moore, J. H. Gillanders, M. Nicholl, M. E. Huber, S. J. Smartt, S. Srivastav, H. F. Stevance, T. -W. Chen, K. C. Chambers, J. P. Anderson, M. D. Fulton, S. R. Oates, C. Angus, G. Pignata, N. Erasmus, H. Gao, J. Herman, C. -C. Lin, T. Lowe, E. A. Magnier, P. Minguez, C. -C. Ngeow, X. Sheng, S. A. Sim, K. W. Smith, R. Wainscoat, S. Yang, D. R. Young, K. -J. Zeng
Most stripped-envelope supernova progenitors are thought to be formed through binary interaction, losing hydrogen and/or helium from their outer layers. Ultra-stripped supernovae are an emerging class of transient which are expected to be produced through envelope-stripping by a NS companion. However, relatively few examples are known and the outcomes of such systems can be diverse and are poorly understood at present. Here, we present spectroscopic observations and high-cadence, multi-band photometry of SN 2023zaw, a rapidly evolving supernova with a low ejecta mass discovered in a nearby spiral galaxy at D = 39.7 Mpc. It has significant Milky Way extinction, $E(B-V)_{\rm MW} = 0.21$, and significant (but uncertain) host extinction. Bayesian evidence comparison reveals that nickel is not the only power source and an additional energy source is required to explain our observations. Our models suggest an ejecta mass of $M_{\rm ej} \sim 0.07$ $\rm M_{\odot}$ and a synthesized nickel mass of $M_{\rm Ni} \sim 0.007$ $\rm M_{\odot}$ are required to explain the observations. We find that additional heating from a central engine, or interaction with circumstellar material can power the early light curve.
We examine the binding energies of massive stripped-envelope core collapse supernova (SECCSN) progenitors with the stellar evolution code MESA, and find that the jittering jets explosion mechanism is preferred for explosions where carbon-oxygen cores with masses of $>20 M_\odot$ collapse to leave a neutron star (NS) remnant. We calculate the binding energy at core collapse under the assumption that the remnant is a NS. Namely, stellar gas above mass coordinate of $~1.5-2.5 M_\odot$ is ejected in the explosion. We find that the typical binding energy of the ejecta of stripped-envelope progenito…
Most massive stars are born in binary or higher-order multiple systems and exchange mass with a companion during their lives. In particular, the progenitors of a large fraction of compact object mergers, and Galactic neutron stars (NSs) and black holes (BHs) have been stripped off their envelopes by a binary companion. Here, we study the evolution of single and stripped binary stars up to core collapse with the stellar evolution code MESA and their final fates with a parametric supernova (SN) model. We find that stripped binary stars can have systematically different pre-SN structures compared…
Most massive stars experience binary interactions in their lifetimes that can alter both the surface and core structure of the stripped star with significant effects on their ultimate fate as core-collapse supernovae. However, core-collapse supernovae simulations to date have focused almost exclusively on the evolution of single stars. We present a systematic simulation study of single and binary-stripped stars with the same initial mass as candidates for core-collapse supernovae (11 - 21 M$_{\odot}$). Generally, we find that binary-stripped stars core tend to be less compact, with a more prom…
In this paper, we discuss the outcomes of the follow-up campaign of SN 2018ijp, discovered as part of the Zwicky Transient Facility survey for optical transients. Its first spectrum shows similarities to broad-lined Type Ic supernovae around maximum light, whereas later spectra display strong signatures of interaction between rapidly expanding ejecta and a dense H-rich circumstellar medium, coinciding with a second peak in the photometric evolution of the transient. This evolution, along with the results of modeling of the first light curve peak, suggests a scenario where a stripped star explo…
Type Iax supenovae (SNe Iax) are an important sub-luminous class of SNe Ia. However, their progenitors and explosion mechanism have not been understood yet. It has been suggested that SNe Iax may be produced from weak deflagration explosions of Chandrasekhar-mass white dwarfs (WDs) in binary systems with a helium (He) star donor. In such progenitor systems, the stripped He companion material caused by the ejecta-companion interaction is expected to present some He features in their late-time spectra. However, the detection of He lines in late-time spectra of SNe Iax has not yet been successful…
In the single-degenerate scenario of Type Ia supernovae (SNe Ia), the interaction between high-speed ejected material and the donor star in a binary system is expected to lead to mass being stripped from the donor. A series of multi-dimensional hydrodynamical simulations of ejecta-donor interaction have been performed in previous studies most of which adopt either a simplified analytical model or the W7 model to represent a normal SN Ia explosion. Whether different explosion mechanisms can significantly affect the results of ejecta-donor interaction is still unclear. In this work, we simulate …
An ultra-stripped supernova (SN) is an explosion of a helium or C+O star whose outer envelope has been stripped away by a companion neutron star. A double neutron star (DNS) binary is believed to be left after the explosion, which will emit the gravitational wave later at the coalescence. Recent detections of a few candidates for the ultra-stripped SN have constrained the properties of the explosion and the progenitor, but little information is given as to whether the remnant DNS binary will merge within the cosmic age. A large fraction of the material stripped away from the helium star throug…
Mixing of 56Ni, whose nuclear decay energy is a major luminosity source in stripped-envelope supernovae, is known to affect the observational properties of stripped-envelope supernovae such as light-curve and color evolution. Here we systematically investigate the effect of 56Ni mixing on the photospheric velocity evolution in stripped-envelope supernovae. We show that 56Ni mixing significantly affects the early photospheric velocity evolution. The photospheric velocity, which is often used to constrain the ejecta mass and explosion energy, significantly varies by just changing the degree of 5…
Stripped-envelope stars can be observed as Wolf-Rayet (WR) stars, or as less luminous hydrogen-poor stars with low mass loss rates and transparent winds. Both types are potential progenitors of Type I core-collapse supernovae (SNe). We use grids of core-collapse models obtained from helium stars at different metallicities to study the effects of metallicity on the transients and remnants these stars produce. We characterise the surface and core properties of our core collapse models, and investigate their explodability employing three criteria. In cases where explosions are predicted, we estim…
Explosive nucleosynthesis of ultra-stripped Type Ic supernovae: application to light trans-iron elements
研究了由1.45和1.5 M $_\odot$ CO星演化的超剥离Ic型超新星在中微子驱动的二维爆炸过程中的爆炸核合成。这些超新星以$\sim 10^{50}$ erg的爆炸能量爆炸并释放出$\sim 0.1$ M $_\odot$喷出物。轻的反式铁元素Ga-Zr在中微子辐照的喷出物中产生。这些元素的丰度分布有很大的不确定性，因为中微子照射的喷出物的电子分数的不确定性。元素的产率将小于0.01 M $_\odot$。由轻CO核演化而来的超剥离超新星和核塌缩超新星可能是轻反式铁元素的主要来源。它们也能产生富中子核$^{48}$ Ca。超剥离超新星喷出$^{56}$ Ni，$\sim$为0.006 - 0.01 M $_\odot$。如果大部分中微子辐照的喷出物是富质子的，则会产生更多的$^{56}$ Ni。这些超新星的光变曲线表明它们是一种亚发光的快速衰变爆炸，峰值量级约为$-15$ - $-16$。未来对超剥离超新星的观测可能会对一类中子星合并的事件率产生限制。
Stripped-envelope supernovae (SE SNe) of Type Ib and Type Ic are thought to result from explosions of massive stars having lost their outer envelopes. The favoured explosion mechanism is by core-collapse, with the shock later revived by neutrino heating. However, there is an upper limit to the amount of radioactive Nickel-56 that such models can accomplish. Recent literature point to a tension between the maximum luminosity from such simulations and observations. We use a well characterized sample of SE SNe from the Zwicky Transient Facility (ZTF) Bright Transient Survey (BTS) to collect a sam…
Ultra-stripped supernovae (USSN) with a relatively low ejecta mass of $\sim0.1M_\odot$ (e.g., iPTF14gqr and SN2019dge) are considered to originate from ultra-stripped carbon-oxygen (CO) cores in close binary systems and are likely to be progenitors of binary neutron stars (BNSs). Here we conduct long-term simulations of USSNe from ultra-stripped progenitors with various masses ($1.45\,M_\odot \leq M_\mathrm{CO} \leq 2.0\,M_\odot$) based on results of neutrino-radiation hydrodynamics simulations, and consistently calculate the nucleosynthesis and the SN light curves. We find that a USSN from a …
Ultra-stripped supernovae are different from other terminal explosions of massive stars, as they show little or no ejecta from the actual supernova event. They are thought to occur in massive binary systems after the exploding star has lost its surface through interactions with its companion. Such supernovae produce little to no kick, leading to the formation of a neutron star without loss of the binary companion, which itself may also evolve into another neutron star. Here we show that a recently discovered high-mass X-ray binary, CPD -29 2176 (CD -29 5159; SGR 0755-2933), has an evolutionary…
Details of the core-collapse supernova (CCSN) explosion mechanism still need to be fully understood. There is an increasing number of successful examples of reproducing explosions in multidimensional hydrodynamic simulations, but subsequent studies pointed out that the growth rates of the explosion energy $\dot{E}_\mathrm{expl}$ of these simulations are insufficient to produce enough $^{56}$Ni to match observations. This issue is known as the `$^{56}$Ni problem' in CCSNe. Recently, however, some studies have suggested that this $^{56}$Ni problem is derived from the simplicity of the explosion …
An optimized radio follow-up strategy for stripped-envelope core-collapse supernovae
几个正在进行或计划进行的天气光学调查提供或即将提供一个前所未有的机会，发现更大的样本的最罕见类型的剥离信封核心坍缩超新星（SNe），如那些与相对论喷流，轻度相对论喷出物，或强相互作用与星周介质（CSM）。无线电波长的观测是探测最快移动的喷出物以及更密集的星周环境的有用工具，因此可以帮助我们识别最罕见的核心塌陷爆炸类型。在这里，我们将讨论如何建立一个有效的无线电后续程序，以检测和正确识别无线电发射剥离信封核心崩溃爆炸。我们使用一种类似于\citealt{Carbone2018}中描述的方法，并确定GHz射电观测的最佳定时，假设灵敏度与Karl G. Jansky甚大阵。进行优化是为了确保收集到的射电观测可以通过使用尽可能少的望远镜时间来识别为射电对应物提供动力的爆炸类型。我们还提出了一个以前未发表的上限的晚期射电辐射超新星iPTF17cw。最后，我们通过讨论X射线的后续影响得出结论。
Stripped-envelope supernovae (Types IIb, Ib, and Ic) that show little or no hydrogen comprise roughly one-third of the observed explosions of massive stars. Their origin and the evolution of their progenitors are not yet fully understood. Very massive single stars stripped by their own winds ($\gtrsim 25-30 M_{\odot}$ at solar metallicity) are considered viable progenitors of these events. However, recent 1D core-collapse simulations show that some massive stars may collapse directly into black holes after a failed explosion, with a weak or no visible transient. In this letter, we estimate the…
Recent discoveries of double neutron star (DNS) mergers and ultra-stripped supernovae (SNe) raise the questions of their origin and connection. We present the first 1D~model of a DNS progenitor system which is calculated self-consistently until an ultra-stripped iron core collapse. We apply the \texttt{MESA} code starting from a post-common envelope binary consisting of a $1.35\;M_\odot$ NS and a $3.20\;M_\odot$ zero-age main-sequence helium star and continue the modelling via Case~BB Roche-lobe overflow until the infall velocity of the collapsing iron core exceeds $1000\;{\rm km\,s}^{-1}$. Th…
The nature of the peculiar `Ca-rich' SN 2019ehk in the nearby galaxy M100 remains unclear. Its origin has been debated as either a stripped core-collapse supernova or a thermonuclear helium detonation event. Here, we present very late-time photometry of the transient obtained with the Keck I telescope at $\approx280$ days from peak light. Using the photometry to perform accurate flux calibration of a contemporaneous nebular phase spectrum, we measure an [O I] luminosity of $(0.19-1.08)\times10^{38}$ erg s$^{-1}$ and [Ca II] luminosity of $(2.7-15.6)\times10^{38}$ erg s$^{-1}$ over the range of…
The diversity of Type II supernovae (SNe II) is thought to be driven mainly by differences in their progenitor's hydrogen-rich (H-rich) envelope mass, with SNe IIP having long plateaus ($\sim100$ days) and the most massive H-rich envelopes. However, it is an ongoing mystery why SNe II with short plateaus (tens of days) are rarely seen. Here, we present optical/near-infrared photometric and spectroscopic observations of luminous Type II short-plateau SNe 2006Y, 2006ai, and 2016egz. Their plateaus of about $50$-$70$ days and luminous optical peaks ($\lesssim-18.4$ mag) indicate significant pre-e…
The discovery of rapidly rising and fading supernovae powered by circumstellar interaction has suggested the pre-supernova mass eruption phase as a critical phenomenon in massive star evolution. It is important to understand the mass and radial extent of the circumstellar medium (CSM) from theoretically predicted mass ejection mechanisms. In this work, we study the wave heating process in massive hydrogen-poor stars, running a suite of stellar models in order to predict the wave energy and pre-explosion time scale of surface energy deposition. We survey stellar models with main sequence progen…
