We present the isotope yields of two post-explosion, three-dimensional 15 $M_\odot$ core-collapse supernova models, 15S and 15A, and compare them to the carbon, nitrogen, silicon, aluminum, sulfur, calcium, titanium, iron, and nickel isotopic compositions of SiC stardust. We find that these core-collapse supernova models predict similar carbon and nitrogen compositions to SiC X grains and grains with $^{12}$C/$^{13}$C $<$ 20 and $^{14}$N/$^{15}$N $<$ 60, which we will hereafter refer to as SiC 'D' grains. Material from the interior of a 15 $M_\odot$ explosion reaches high enough temperatures shortly after core collapse to produce the large enrichments of $^{13}$C and $^{15}$N necessary to replicate the compositions of SiC D grains. The innermost ejecta in a core-collapse supernova is operating in the neutrino-driven regime and undergoes fast proton capture after being heated by the supernova shockwave. Both 3-D models predict 0.3 $<$ $^{26}$Al/$^{27}$Al $<$ 1.5, comparable to the ratios seen in SiC X, C, and D grains. Models 15S and 15A, in general, predict very large anomalies in calcium isotopes but do compare qualitatively with the SiC X grain measurements that show $^{44}$Ca and $^{43}$Ca excesses. The titanium isotopic compositions of SiC X grains are well reproduced. The models predict $^{57}$Fe excesses and depletions that are observed in SiC X grains, and in addition predict accurately the $^{60}$Ni/$^{58}$Ni, $^{61}$Ni/$^{58}$Ni, and $^{62}$Ni/$^{58}$Ni ratios in SiC X grains, as a result of fast neutron captures initiated by the propagation of the supernova shockwave. Finally, symmetry has a noticeable effect on the production of silicon, sulfur, and iron isotopes in the SN ejecta.
In the transitional mass range ($\sim$ 8-10 solar masses) between white dwarf formation and iron core-collapse supernovae, stars are expected to produce an electron-capture supernova. Theoretically, these progenitors are thought to be super-asymptotic giant branch stars with a degenerate O+Ne+Mg core, and electron capture onto Ne and Mg nuclei should initiate core collapse. However, no supernovae have unequivocally been identified from an electron-capture origin, partly because of uncertainty in theoretical predictions. Here we present six indicators of electron-capture supernovae and show tha…
This paper presents a short review on the current state of SN Ia progenitor origin. Type Ia supernova explosions are observed to be widely diverse in peak luminosity, lightcurve width and shape, spectral features, and host stellar population environment. In the last decade alone, theoretical simulations and observational data have come together to seriously challenge the long-standing paradigm that all SNe Ia arise from explosions of Chandrasekhar mass white dwarfs. In this review I highlight some of the major developments (and changing views) of our understanding of the nature of SN Ia progen…
Massive binaries play an important role in fields ranging from gravitational wave astronomy to stellar evolution. We provide several lines of evidence that classical OBe stars in the Small Magellanic Cloud (SMC) obtain their rapid rotation from mass and angular momentum transfer in massive binaries, which predicts that the subsequent supernovae should often eject OBe stars into the field. We find that (1) OBe stars have a higher field frequency than OB stars; (2) our cumulative distribution function (CDF) of stellar distances from O stars shows that OBe stars are indeed much more isolated than…
Magnetars are regarded as the most magnetized neutron stars in the Universe. Aiming to unveil what kinds of stars and supernovae can create magnetars, we have performed a state-of-the-art spatially resolved spectroscopic X-ray study of the supernova remnants (SNRs) Kes 73, RCW 103, and N49, which host magnetars 1E 1841-045, 1E 161348-5055, and SGR 0526-66, respectively. The three SNRs are O- and Ne-enhanced and are evolving in the interstellar medium with densities of >1--2 cm$^{-3}$. The metal composition and dense environment indicate that the progenitor stars are not very massive. The proge…
The guest star of AD 1181 is the only historical supernova of the last millennium that is without a definite counterpart. The previously proposed association with supernova remnant 3C58 is in strong doubt because of the inferred age of this remnant. Here we report a new identification of SN 1181 with our codiscovery of the hottest known Wolf Rayet star of the Oxygen sequence (dubbed Parkers star) and its surrounding nebula Pa 30. Our spectroscopy of the nebula shows a fast shock with extreme velocities of approx. 1,100kms. The derived expansion age of the nebula implies an explosive event appr…
Recently, several accreting neutron stars (NSs) in X-ray binary systems inside supernova remnants have been discovered. They represent a puzzle for the standard magneto-rotational evolution of NSs, as their ages ($\lesssim 10^5$ years) are much shorter than the expected duration of Ejector and Propeller stages preceding the onset of wind accretion. To explain appearance of such systems, we consider rotational evolution of NSs with early fallback accretion and asymmetry in forward/backward transitions between Ejector and Propeller stages (so-called hysteresis effect proposed by V. Shvartsman in…
HB9 (G160.9+2.6) is a mixed-morphology Galactic supernova remnant (SNR) at a distance of $\sim$0.6 kpc. Previous analyses revealed recombining plasma emission in X-rays and an expanding shell structure in HI and CO emission, which were correlating with the spatial extent of HB9. In GeV energies, HB9 was found to show extended gamma-ray emission with a morphology that is consistent with the radio continuum emission showing a log-parabola-type spectrum. The overlap reported between the gas data and the excess gamma-ray emission at the southern region of the SNR's shell could indicate a possible …
The Type Ia supernova (SN Ia) LSQ14fmg exhibits exaggerated properties which may help to reveal the origin of the "super-Chandrasekhar" (or 03fg-like) group. The optical spectrum is typical of a 03fg-like SN Ia, but the light curves are unlike those of any SNe Ia observed. The light curves of LSQ14fmg rise extremely slowly. At -23 rest-frame days relative to B-band maximum, LSQ14fmg is already brighter than $M_V$=-19 mag before host extinction correction. The observed color curves show a flat evolution from the earliest observation to approximately one week after maximum. The near-infrared lig…
Nucleosynthetic Fe isotopic anomalies in meteorites may be used to reconstruct the early dynamical evolution of the solar system and to identify the origin and nature of the material that built planets. Using high-precision iron isotopic data of 23 iron meteorites from nine major chemical groups we show that all iron meteorites show the same fundamental dichotomy between non-carbonaceous (NC) and a carbonaceous (CC) meteorites previously observed for other elements. The Fe isotopic anomalies are predominantly produced by variation in 54Fe, where all CC iron meteorites are characterized by an e…
Several stars detected moving at velocities near to or exceeding the Galactic escape speed likely originated in the Milky Way disc. We quantitatively explore the `binary supernova scenario' hypothesis, wherein these `hyper-runaway' stars are ejected at large peculiar velocities when their close, massive binary companions undergo a core-collapse supernova and the binary is disrupted. We perform an extensive suite of binary population synthesis simulations evolving massive systems to determine the assumptions and parameters which most impact the ejection rate of fast stars. In a simulation tailo…
The distribution of the very-high-energy diffuse emission in the inner 200 pc measured by HE.S.S. indicates the existence of a pronounced cosmic-ray (CR) gradient peaking on the Galactic center (GC). Previous studies have shown that these data are consistent with a scenario in which the CRs are diffused away from a stationary source at the GC. We previously showed that, taking the 3D gas distribution and a realistic distribution of supernova explosions into account, CRs accelerated in supernova remnants (SNR) should account for a large fraction of the GC CRs observed by H.E.S.S.; but the model…
The physical origin of the overionized recombining plasmas (RPs) in supernova remnants (SNRs) has been attracting attention because its understanding provides new insight into SNR evolution. However, the process of the overionization, although it has been discussed in some RP-SNRs, is not yet fully understood. Here we report on spatially resolved spectroscopy of X-ray emission from IC~443 with {\it XMM-Newton}. We find that RPs in regions interacting with dense molecular clouds tend to have lower electron temperature and lower recombination timescale. These tendencies indicate that RPs in thes…
University of Florida（佛罗里达大学）；Center for Astrophysics | Harvard & Smithsonian（哈佛-史密森尼天体物理中心）；California Institute of Technology（加州理工学院）；The University of Tokyo（东京大学）；The University of Texas at Austin（德克萨斯大学奥斯汀分校）；National Astronomical Observatory of Japan, National Institutes of Natural Sciences（日本国立天文台，国立自然科学研究院）
Recent X-ray studies revealed over-ionized recombining plasmas (RPs) in a dozen mixed-morphology (MM) supernova remnants (SNRs). However, the physical process of the over-ionization has not been fully understood yet. Here we report on spatially resolved spectroscopy of X-ray emission from W44, one of the over-ionized MM-SNRs, using XMM-Newton data from deep observations, aiming to clarify the physical origin of the over-ionization. We find that combination of low electron temperature and low recombination timescale is achieved in the region interacting with dense molecular clouds. Moreover, a …
Of the known microquasars, V4641 Sgr boasts the most severe lower limit (> 52°) on the misalignment angle between the relativistic jet axis and the binary orbital angular momentum. Assuming the jet and black hole spin axes coincide, we attempt to explain the origin of this extreme spin-orbit misalignment with a natal kick model, whereby an aligned binary system becomes misaligned by a supernova kick imparted to the newborn black hole. The model inputs are the kick velocity distribution, which we measure customized to V4641 Sgr, and the immediate pre/post-supernova binary system parameters. Usi…
The Origin of Recombining Plasma and the Detection of the Fe-K Line in the Supernova Remnant W28
在十几个混合形态超新星遗迹中发现了过电离复合等离子体.然而，其形成过程仍在争论之中。正如许多先前的研究所指出的，等离子体温度和电离状态的空间变化提供了线索，以了解RP的物理起源。我们报告的W28，这是在我们的银河系中发现的最大的MM SNRs之一的空间分辨X射线光谱。朱雀XIS的两次观测覆盖了W28的中心到东北边缘，那里的激波与分子云相互作用。两个不同温度和电离状态的RP模型的组合很好地再现了内部区域的X射线谱，而东北边缘的X射线谱则用单RP模型解释。我们在东北边缘发现的RP表明云和热等离子体之间的热传导效应，这可能是RP的产生过程。东北边缘的X射线光谱也显示出Fe I Kα线的过量发射。最有可能解释这条线的过程是分子云中的Fe被W28中加速的宇宙射线粒子内壳层电离。
{\it Chandra} X-ray observations of Kepler's supernova remnant indicate the existence of a high speed Fe-rich ejecta structure in the southwestern region. We report strong K-shell emission from Fe-peak elements (Cr, Mn, Fe, Ni), as well as Ca, in this Fe-rich structure, implying that those elements could be produced in the inner area of the exploding white dwarf. We found Ca/Fe, Cr/Fe, Mn/Fe and Ni/Fe mass ratios of 1.0--4.1\%, 1.0--4.6\%, 1--11\% and 2--30\%, respectively. In order to constrain the burning regime that could produce this structure, we compared these observed mass ratios with t…
Using $λ$-21-cm galactic neutral atomic hydrogen data from the HI4PI survey of Bekhti et al. (2016) and 0.75-30 MeV $γ$-ray emission from the Imaging Compton Telescope, we have searched for the origin event that accelerated high velocity cloud Complex M. Radio plots of $l-b$, $l-v$, and $b-v$ show a cavity centered at ($l$, $b$) $\sim$ (150$^{\circ}$, 50.$^{\circ}$) and extending about $\pm$33$^{\circ}$. The best view of the cavity is at a velocity of -25 km s$^{-1}$, which shows a circular cross section on the back (receding) face. Complex M, at -85 km s$^{-1}$, is on the front (approaching) …
X-ray observations of supernova remnants (SNRs) in the last decade have shown that the presence of recombining plasmas is somewhat common in a certain type of object. The SNR W49B is the youngest, hottest, and most highly ionized among such objects and hence provides crucial information about how the recombination phase is reached during the early evolutionary phase of SNRs. In particular, spectral properties of radiative recombination continuum (RRC) from Fe are the key for constraining the detailed plasma conditions. Here we present imaging and spectral studies of W49B with Nuclear Spectrosc…
The Search for Stable Nickel: Investigating the Origins of Type Ia Supernovae with Late-time NIR Spectroscopy from the Carnegie Supernova Project-II
University of Virginia（弗吉尼亚大学）；Florida State University（佛罗里达州立大学）；University of Hawai’i（夏威夷大学）；Planetary Science Institute（行星科学研究所）；Hamburger Sternwarte（汉堡天文台）；Carnegie Observatories（卡内基观测站）；Purdue University（普渡大学）；Observatories of the Carnegie Institution for Science（卡内基科学研究所天文台）；Michigan State University（密歇根州立大学）；Space Telescope Science Institute（太空望远镜科学研究所）；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 of Space Sciences (ICE, CSIC)（空间科学研究所）；Institut d’Estudis Espacials de Catalunya (IEEC)（加泰罗尼亚空间研究研究所）；Aarhus University（奥胡斯大学）；American Public University System（美国公立大学系统）；Independent University, Bangladesh（孟加拉独立大学）；Rutgers, the State University of New Jersey（新泽西罗格斯大学）；Texas A&M University（德克萨斯农工大学）
The synchrotron radiation from secondary electrons and positrons (SEPs) generated by hadronic interactions in the shock of supernova remnant (SNR) could be a distinct evidence of cosmic ray (CR) production in SNR shocks. Here we provide a method where the observed gamma-ray flux from SNRs, created by pion decays, is directly used to derive the SEP distribution and hence the synchrotron spectrum. We apply the method to three gamma-ray bright SNRs. In the young SNR RX J1713.7-3946, if the observed GeV-TeV gamma-rays are of hadronic origin and the magnetic field in the SNR shock is $B\gtrsim 0.5$…
The Single-degenerate Binary Origin of Tycho's Supernova as Traced by the Stripped Envelope of the Companion
我们提出，一个非热的X射线弧内的第谷超新星（SN）的残余代表SN喷出物和伴星的信封之间的相互作用在爆炸的影响。残余物的X射线辐射进一步显示了一个明显的阴影，由电弧投射在爆炸地点的相反方向，与被外壳阻挡的SN喷出物一致。这种情况支持第谷SN的单一简并双星起源。X射线弧的性质，以及Ruiz-Lapuente等人（2004年）和Hernández等人先前对伴星候选者及其空间速度的探测。（2009），使我们能够进一步推断：1）祖先双星的周期为4.9 $^{+5.3}_{-3.0}$天，2）伴星的反冲速度为42 $\pm$ 30 km s $^{-1}$，3）剥离包层质量约为0.0016（$\leq0.0083$）$M_{\sun}$。但我们注意到，伴随候选的性质仍在争论中，上述参数需要根据伴随候选的实际性质进行修改。还需要进一步的工作来测量电弧的适当运动，并检查从电弧中观察到的相互作用发射X射线量的能力，以验证当前的情况。
