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The search for the progenitors of six core-collapse supernovae (CCSNe) in archival Hubble Space Telescope ( HST ) WFPC2 pre-explosion imaging is presented. These SNe are 1999an, 1999br, 1999ev, 2000ds, 2000ew and 2001B. Post-explosion imaging of the SNe, with the HST ACS/WFC, has been utilized with the technique of differential astrometry to identify the progenitor locations on the pre-explosion imaging. SNe 1999br, 1999ev, 2000ew and 2001B are recovered in late-time imaging, and estimates of the progenitor locations on the pre-explosion imaging, with subpixel accuracy, have been made. Only the progenitor of the Type II-P SN 1999ev has been recovered, on pre-explosion F555W imaging, at a 4.8σ significance level. Assuming a red supergiant progenitor, the pre-explosion observation is consistent with M ZAMS = 15–18 M⊙ . The progenitors of the other five SNe were below the 3σ detection threshold of the pre-explosion observations. The detection thresholds were translated to mass limits for the progenitors by comparison with stellar evolution models. Pre-explosion observations of the peculiarly faint SN 1999br limit the mass of a red supergiant progenitor to M ZAMS < 12 M⊙ . Analysis has been extended, from previous studies, to include possible detections of high- T eff , high-mass stars by conducting synthetic photometry of model Wolf–Rayet star spectra. The mass limits for the Type II-P SNe 1999an and 1999br are consistent with previously determined mass limits for this type of SN. The detection limits for the progenitors of the Type Ibc SNe (2000ds, 2000ew and 2001B) do not permit differentiation between high-mass Wolf–Rayet progenitors or low-mass progenitors in binaries. 相似文献
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A. Pastorello S. Mattila L. Zampieri M. Della Valle S. J. Smartt S. Valenti I. Agnoletto S. Benetti C. R. Benn D. Branch E. Cappellaro M. Dennefeld J. J. Eldridge A. Gal-Yam A. Harutyunyan I. Hunter H. Kjeldsen Y. Lipkin P. A. Mazzali P. Milne H. Navasardyan E. O. Ofek E. Pian O. Shemmer S. Spiro R. A. Stathakis S. Taubenberger M. Turatto H. Yamaoka 《Monthly notices of the Royal Astronomical Society》2008,389(1):113-130
We present new spectroscopic and photometric data of the Type Ibn supernovae 2006jc, 2000er and 2002ao. We discuss the general properties of this recently proposed supernova family, which also includes SN 1999cq. The early-time monitoring of SN 2000er traces the evolution of this class of objects during the first few days after the shock breakout. An overall similarity in the photometric and spectroscopic evolution is found among the members of this group, which would be unexpected if the energy in these core-collapse events was dominated by the interaction between supernova ejecta and circumstellar medium. Type Ibn supernovae appear to be rather normal Type Ib/c supernova explosions which occur within a He-rich circumstellar environment. SNe Ibn are therefore likely produced by the explosion of Wolf–Rayet progenitors still embedded in the He-rich material lost by the star in recent mass-loss episodes, which resemble known luminous blue variable eruptions. The evolved Wolf–Rayet star could either result from the evolution of a very massive star or be the more evolved member of a massive binary system. We also suggest that there are a number of arguments in favour of a Type Ibn classification for the historical SN 1885A (S-Andromedae), previously considered as an anomalous Type Ia event with some resemblance to SN 1991bg. 相似文献
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A. Pastorello R. M. Quimby † S. J. Smartt S. Mattila H. Navasardyan R. M. Crockett N. Elias-Rosa P. Mondol J. C. Wheeler D. R. Young 《Monthly notices of the Royal Astronomical Society》2008,389(1):131-140
We present photometric and spectroscopic data of the peculiar SN 2005la, an object which shows an optical light curve with some luminosity fluctuations and spectra with comparably strong narrow hydrogen and helium lines, probably of circumstellar nature. The increasing full width at half-maximum velocity of these lines is indicative of an acceleration of the circumstellar material. SN 2005la exhibits hybrid properties, sharing some similarities with both Type IIn supernovae and 2006jc-like (Type Ibn) events. We propose that the progenitor of SN 2005la was a very young Wolf–Rayet (WN-type) star which experienced mass ejection episodes shortly before core collapse. 相似文献
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S. Benetti M. Turatto S. Balberg L. Zampieri S. L. Shapiro E. Cappellaro K. Nomoto T. Nakamura P. A. Mazzali F. Patat 《Monthly notices of the Royal Astronomical Society》2001,322(2):361-368
We present a new set of spectroscopic and photometric data extending the observations of SN 1997D to over 400 d after the explosion. These observations confirm the peculiar properties of SN 1997D, such as the very low abundance of 56 Co (0.002 M⊙ ) and the low expansion velocity of the ejecta (∼1000 km s−1 ). We discuss the implications of these observations for the character of the progenitor and the nature of the remnant, showing that a Crab-like pulsar or an accreting neutron star formed in the explosion of a low-mass progenitor should already have produced a detectable luminosity at this epoch, in contrast with photometric data. On the other hand, the explosion of a high-mass progenitor with the formation of a black hole is consistent with the available observations. The consequences of this conclusion regarding the nature of the explosion and the prospects of directly identifying the black hole are also addressed. 相似文献
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G. Pignata S. Benetti P. A. Mazzali R. Kotak F. Patat P. Meikle M. Stehle B. Leibundgut N. B. Suntzeff L. M. Buson E. Cappellaro A. Clocchiatti M. Hamuy J. Maza J. Mendez P. Ruiz-Lapuente M. Salvo B. P. Schmidt M. Turatto W. Hillebrandt 《Monthly notices of the Royal Astronomical Society》2008,388(3):971-990
As part of the European Supernova Collaboration, we obtained extensive photometry and spectroscopy of the Type Ia supernova (SN Ia) SN 2002dj covering epochs from 11 d before to nearly two years after maximum. Detailed optical and near-infrared observations show that this object belongs to the class of the high-velocity gradient events as indicated by Si, S and Ca lines. The light curve shape and velocity evolution of SN 2002dj appear to be nearly identical to SN 2002bo. The only significant difference is observed in the optical to near-infrared colours and a reduced spectral emission beyond 6500 Å. For high-velocity gradient SNe Ia, we tentatively identify a faster rise to maximum, a more pronounced inflection in the V and R light curves after maximum and a brighter, slower declining late-time B light curve as common photometric properties of this class of objects. They also seem to be characterized by a different colour and colour evolution with respect to 'normal' SNe Ia. The usual light curve shape parameters do not distinguish these events. Stronger, more blueshifted absorption features of intermediate-mass elements and lower temperatures are the most prominent spectroscopic features of SNe Ia displaying high-velocity gradients. It appears that these events burn more intermediate-mass elements in the outer layers. Possible connections to the metallicity of the progenitor star are explored. 相似文献
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Bruno Leibundgut 《Astronomy and Astrophysics Review》2000,10(3):179-209
Summary. Type Ia Supernovae are in many aspects still enigmatic objects. Their observational and theoretical exploration is in full
swing, but we still have plenty to learn about these explosions.
Recent years have already witnessed a bonanza of supernova observations. The increased samples from dedicated searches have
allowed the statistical investigation of Type Ia Supernovae as a class. The observational data on Type Ia Supernovae are very
rich, but the uniform picture of a decade ago has been replaced by several correlations which connect the maximum luminosity
with light curve shape, color evolution, spectral appearance, and host galaxy morphology. These correlations hold across almost
the complete spectrum of Type Ia Supernovae, with a number of notable exceptions. After 150 days past maximum, however, all
observed objects show the same decline rate and spectrum.
The observational constraints on explosion models are still rather sparse. Global parameters like synthesized nickel mass,
total ejecta mass and explosion energetics are within reach in the next few years. These parameters bypass the complicated
calculations of explosion models and radiation transport. The bolometric light curves are a handy tool to investigate the
overall appearance of Type Ia Supernovae. The nickel masses derived this way show large variations, which combined with the
dynamics from line widths, indicate that the brighter events are also coming from more massive objects.
The lack of accurate distances and the uncertainty in the correction for absorption are hampering further progress. Improvements
in these areas are vital for the detailed comparison of luminosities and the determination of nickel masses. Coverage at near-infrared
wavelengths for a statistical sample of Type Ia Supernovae will at least decrease the dependence on the absorption. Some of
the most intriguing features of Type Ia Supernovae are best observed at these wavelengths, like the second peak in the light
curve, the depression in the J band, and the unblended [Feii] lines in the ashes.
Received 24 January 2000 / Published online 8 May 2000 相似文献
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A. Pastorello E. Baron D. Branch L. Zampieri M. Turatto M. Ramina S. Benetti E. Cappellaro M. Salvo F. Patat A. Piemonte J. Sollerman B. Leibundgut G. Altavilla 《Monthly notices of the Royal Astronomical Society》2005,360(3):950-962
We present spectroscopic and photometric observations of the peculiar Type II supernova (SN) 1998A. The light curves and spectra closely resemble those of SN 1987A, suggesting that the SN 1998A progenitor exploded when it was a compact blue supergiant. However, the comparison with SN 1987A also highlights some important differences: SN 1998A is more luminous and the spectra show bluer continua and larger expansion velocities at all epochs. These observational properties indicate that the explosion of SN 1998A is more energetic than SN 1987A and more typical of Type II supernovae. Comparing the observational data with simulations, we deduce that the progenitor of SN 1998A was a massive star (∼25 M⊙ ) with a small pre-supernova radius (≲6 × 1012 cm) . The Ba ii lines, unusually strong in SN 1987A and some faint II-P events, are almost normal in the case of SN 1998A, indicating that the temperature plays a key role in determining their strength. 相似文献
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本文用完全动力学程式计算了Ⅰ型超新星爆发。这些模型是依据氦或碳和氧构成星核,部分地或全部地产生瞬时完成的核燃烧。计算中将动力学方程、核统计平衡、Rayleigh-Taylor不稳定性等物理过程联合起来求解。重点比较了Rayleigh-Taylor不稳定性的影响,现不能作出完全肯定的结论。计算结果列在表1、表2和图2—6中。 相似文献
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A. Pastorello D. Sauer S. Taubenberger P. A. Mazzali K. Nomoto K. S. Kawabata S. Benetti N. Elias-Rosa A. Harutyunyan H. Navasardyan L. Zampieri T. Iijima M. T. Botticella G. Di Rico M. Del Principe M. Dolci S. Gagliardi M. Ragni G. Valentini 《Monthly notices of the Royal Astronomical Society》2006,370(4):1752-1762
Early-time optical observations of supernova (SN) 2005cs in the Whirlpool Galaxy (M51) are reported. Photometric data suggest that SN 2005cs is a moderately underluminous Type II plateau SN (SN IIP). The SN was unusually blue at early epochs ( U − B ≈−0.9 about three days after explosion) which indicates very high continuum temperatures. The spectra show relatively narrow P Cygni features, suggesting ejecta velocities lower than observed in more typical SNe IIP. The earliest spectra show weak absorption features in the blue wing of the He i 5876-Å absorption component and, less clearly, of Hβ and Hα. Based on spectral modelling, two different interpretations can be proposed: these features may either be due to high-velocity H and He i components, or (more likely) be produced by different ions (N ii , Si ii ). Analogies with the low-luminosity, 56 Ni-poor, low-velocity SNe IIP are also discussed. While a more extended spectral coverage is necessary in order to determine accurately the properties of the progenitor star, published estimates of the progenitor mass seem not to be consistent with stellar evolution models. 相似文献
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A. Pastorello S. Valenti L. Zampieri H. Navasardyan S. Taubenberger S. J. Smartt A. A. Arkharov O. Bärnbantner H. Barwig S. Benetti P. Birtwhistle M. T. Botticella E. Cappellaro M. Del Principe F. Di Mille G. Di Rico M. Dolci N. Elias-Rosa N. V. Efimova M. Fiedler A. Harutyunyan P. A. Höflich W. Kloehr V. M. Larionov V. Lorenzi J. R. Maund N. Napoleone M. Ragni M. Richmond C. Ries S. Spiro S. Temporin M. Turatto J. C. Wheeler 《Monthly notices of the Royal Astronomical Society》2009,394(4):2266-2282
We present the results of the one-year long observational campaign of the type II plateau SN 2005cs, which exploded in the nearby spiral galaxy M51 (the Whirlpool galaxy). This extensive data set makes SN 2005cs the best observed low-luminosity, 56 Ni-poor type II plateau event so far and one of the best core-collapse supernovae ever. The optical and near-infrared spectra show narrow P-Cygni lines characteristic of this SN family, which are indicative of a very low expansion velocity (about 1000 km s−1 ) of the ejected material. The optical light curves cover both the plateau phase and the late-time radioactive tail, until about 380 d after core-collapse. Numerous unfiltered observations obtained by amateur astronomers give us the rare opportunity to monitor the fast rise to maximum light, lasting about 2 d. In addition to optical observations, we also present near-infrared light curves that (together with already published ultraviolet observations) allow us to construct for the first time a reliable bolometric light curve for an object of this class. Finally, comparing the observed data with those derived from a semi-analytic model, we infer for SN 2005cs a 56 Ni mass of about 3 × 10−3 M⊙ , a total ejected mass of 8–13 M⊙ and an explosion energy of about 3 × 1050 erg . 相似文献
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