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1.
Gillian Pearce Bruce Patchett Paul Murdin Jeremy Allington-Smith 《Astrophysics and Space Science》1990,164(1):59-62
We present the spectrum of the supernova SN1988e over the wavelength range 4750–9000 Å as recorded on 11 February, 1988. The spectrum was taken in one 2000 s exposure using the Faint Object Spectrograph on the 4.2 m William Herschel Telescope (WHT) at the Observatorio del Roque de los Muchachos.We conclude that SN1988e was a type I supernova, and that at the time of observation it had faded 7.5 mag from its predicted magnitude at maximum light. Spectra taken at such late stages in the light curve are comparatively rare, and are made possible only with the application of modern instrumentation. 相似文献
2.
Gillian Pearce Bruce Patchett Jeremy Allington-Smith Ian Parry 《Astrophysics and Space Science》1988,150(2):267-271
We present the spectrum of the supernova SN1987L in NGC 2336 over the wavelength range 4000–9700 Å as recorded in one 500 s exposure on 20–21 October, 1987. This spectrum was taken using the new Faint Object Spectrograph on the 4.2 m William Herschel Telescope (WHT) at the Observatorio del Roque de los Muchachos.We conclude that SN1987L was a type Ia supernova, and approximately 100 days post maximum at the time of the observation. 相似文献
3.
Vasilii Gvaramadze 《Astrophysics and Space Science》2000,274(1-2):195-203
A model of the Vela supernova remnant (SNR) based on a cavity explosion of a supernova (SN) star is proposed. It is suggested
that the general structure of the remnant is determined by the interaction of the SN blast wave with a massive shell created
by the SN progenitor (15-20 M⊙) star. A possible origin of the nebula of hard X-ray emission detected around the Velapulsar is discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
4.
A. Pastorello M. Turatto S. Benetti E. Cappellaro I. J. Danziger P. A. Mazzali F. Patat A. V. Filippenko D. J. Schlegel † T. Matheson ‡ 《Monthly notices of the Royal Astronomical Society》2002,333(1):27-38
We present the photometric and spectroscopic evolution of the type IIn SN 1995G in NGC 1643, on the basis of 4 years of optical and infrared observations. This supernova shows very flat optical light curves similar to SN 1988Z, with a slow decline rate at all times. The spectra are characterized by strong Balmer lines with multiple components in emission and with a P Cygni absorption component blueshifted by only 700 km s−1 . This feature indicates the presence of a slowly expanding shell above the SN ejecta as in the case of SNe 1994aj and 1996L. As in other SNe IIn, the slow luminosity decline cannot be explained only with a radioactive energy input, and an additional source of energy is required, most likely that produced by the interaction between supernova ejecta and a pre-existent circumstellar medium (CSM). It was estimated that the shell material has a density n H ≫108 cm-3 , consistent with the absence of forbidden lines in the spectra. About 2 years after the burst the low-velocity shell is largely overtaken by the SN ejecta and the luminosity drops at a faster rate. 相似文献
5.
Takuji Tsujimoto Toshikazu Shigeyama Yuzuru Yoshii 《Astrophysics and Space Science》2002,281(1-2):221-222
Following our hypothesis that each supernova (SN) event triggers star formation in the swept-up gas, so that newly formed
stars inherit the elemental abundance pattern of individual SNe, we deduce the production sites and yields for r-process elements. We further show that a strong evidence for the origin of r-process nucleosynthesis products was just there in our backyard - supernova SN1987A -, and conclude that 20 M
⊙ SNe are the predominant production sites for r-process elements.
This revised version was published online in September 2006 with corrections to the Cover Date. 相似文献
6.
We consider an improved rotational mechanism of the explosion of a collapsing supernova. We show that this mechanism leads to two-stage collapse with a phase difference of ～5 h. Based on this model, we attempt a new interpretation of the events in underground neutrino detectors on February 23, 1987, related to the supernova SN 1987A. 相似文献
7.
An examination of the histogram of the supernova remnants radii allows one to deduce: (1) some support for the existence of a fairly dense galactic halo at least up to a few kpc from the galactic plane; (2) a first approximation for the initial energy distribution. Although the precise shape is still in doubt and various possibilities exist, one can conclude that the supernova rate should be no less than 1/150 SN yr–1, and no more than 1/70 SN yr–1; the average initial energy should be larger than 1.4×1049 erg. 相似文献
8.
M. A. Hendry S. J. Smartt J. R. Maund A. Pastorello L. Zampieri S. Benetti M. Turatto E. Cappellaro W. P. S. Meikle R. Kotak M. J. Irwin P. G. Jonker L. Vermaas R. F. Peletier H. van Woerden K. M. Exter D. L. Pollacco S. Leon S. Verley C. R. Benn G. Pignata 《Monthly notices of the Royal Astronomical Society》2005,359(3):906-926
We present photometric and spectroscopic data of the Type II-P supernova (SN II-P) 2003gd, which was discovered in M74 close to the end of its plateau phase. SN 2003gd is the first Type II supernova (SN) to have a directly confirmed red supergiant (RSG) progenitor. We compare SN 2003gd to SN 1999em, a similar SN II-P, and estimate an explosion date of 2003 March 18. We determine a reddening towards the SN of E ( B − V ) = 0.14 ± 0.06 , using three different methods. We also calculate three new distances to M74 of 9.6 ± 2.8, 7.7 ± 1.7 and 9.6 ± 2.2 Mpc . The former was estimated using the standard candle method (SCM), for Type II supernovae (SNe II), and the latter two using the brightest supergiants method (BSM). When combined with existing kinematic and BSM distance estimates, we derive a mean value of 9.3 ± 1.8 Mpc . SN 2003gd was found to have a lower tail luminosity compared with other normal Type II-P supernovae (SNe II-P) bringing into question the nature of this SN. We present a discussion concluding that this is a normal SN II-P, which is consistent with the observed progenitor mass of 8+4 −2 M⊙ . 相似文献
9.
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
10.
Zhao Gang Zhao Yong-heng Huang Jia-sheng Feng Long-long Huang Ke-liang Peng Qiu-he Lu Tan 《Chinese Astronomy and Astrophysics》1988,12(4):294-297
We carried out a Monte Carlo simulation calculation on the observed data of neutrino events of the supernova SN1987A. Our results show that the best value for the rest-mass of neutrino is 3–4 eV. We also calculated the light curve of the neutrino bursts and the energy spectrum.Our results impose constraints on the rest-mass of neutrino and the mass of the precursor of SN 1987A. 相似文献
11.
The most luminous Supernova SN2006gy (more than 100 times brighter than a typical supernova) has been a challenge to explain by standard models. For example, pair-instability supernovae which are luminous enough seem to have too slow a rise, and core-collapse supernovae do not seem to be luminous enough. We present an alternative scenario involving a Quark Nova (an explosive transition of the newly born neutron star to a quark star) in which a second explosion (delayed) occurs inside the ejecta of a normal supernova. The reheated supernova ejecta can radiate at higher levels for longer periods of time primarily due to reduced adiabatic-expansion losses, unlike the standard supernova case. We find an encouraging match between the resulting light curve and that observed in the case of SN2006gy suggesting that we might have at hand the first ever signature of a Quark Nova. Successful application of our model to SN2005gj and SN2005ap is also presented. 相似文献
12.
M. A. Kazarian 《Astrophysics》1997,40(3):296-307
A list of galaxies with a UV excess in which at least one supernova (SN) has exploded is compiled. Distributions of the linear
distances of SN in synthetic galaxies are obtained, constructed for galaxies with a UV excess and normal galaxies. It is shown
that SN activity is the same in galaxies with a UV excess and in normal galaxies.
Translated from Astrofizika, Vol. 40, No. 3, pp. 457–472, August, 1997. 相似文献
13.
We investigate the evaporation and condensation of corundum and silicon carbide grains around the supernova SN1987A. We predict the time after outburst of the interaction of the condensed dust with pre-existing dust, with a view to undertaking observations with future instrumentation such as the Infra-Red Space Observatory. 相似文献
14.
We investigate the possibility of detecting the circumstellar Na I D1,2 and Ca II H, K absorption lines in the spectra of type IIP supernovae at the photospheric phase. Our modeling shows that the Na I doublet lines will not be seen in the spectra of type IIP supernovae at moderate stellar wind densities, for example, characteristic of SN 1999em, while the rather intense Ca II lines with P Cyg profiles should be detectable. The same model is used to describe the circumstellar Na I and Ca II lines in the spectrum of SN 1998S, a type IIL supernova with a dense wind. We show that the circumstellar line intensities in this supernova are reproduced only if there is an ultraviolet excess that is mainly attributable to the Comptonization of supernova radiation in the shock wave. 相似文献
15.
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
16.
We present an analysis of archival X-ray observations of the Type IIL supernova SN 1979C. We find that its X-ray luminosity is remarkably constant at (6.5 ± 0.1) × 1038 erg s?1 over a period of 12 years between 1995 and 2007. The high and steady luminosity is considered as possible evidence for a stellar-mass (～5–10 M⊙) black hole accreting material from either a supernova fallback disk or from a binary companion, or possibly from emission from a central pulsar wind nebula. We find that the bright and steady X-ray light curve is not consistent with either a model for a supernova powered by magnetic braking of a rapidly rotating magnetar, or a model where the blast wave is expanding into a dense circumstellar wind. 相似文献
17.
We model the interaction of the supernova SN 1995G with a dense circumstellar (CS) gas in a thin-shell approximation. A model fit to the observed bolometric light curve combined with data on the supernova expansion velocity gives estimates for the density, mass (≈1 M⊙), and age (≈8 yr) of the CS envelope. The determined CS-envelope density is shown to be virtually independent of the assumed mass of the supernova envelope because of the high CS-gas density at which the forward shock wave is essentially radiative. The derived CS-envelope density is consistent with the Hα luminosity and with the presence of distinct Thomson scattering in the red wing of this line. The mass of the CS envelope together with its expansion velocity and age indicate that the CS envelope was ejected by the presupernova eight years before the supernova explosion through violent energy release (～6×1048 erg). 相似文献
18.
Kuntal Misra Dave Pooley † Poonam Chandra D. Bhattacharya Alak K. Ray Ram Sagar Walter H. G. Lewin 《Monthly notices of the Royal Astronomical Society》2007,381(1):280-292
We present X-ray, broad-band optical and low-frequency radio observations of the bright type IIP supernova SN 2004et. The Chandra X-ray Observatory observed the supernova at three epochs, and the optical coverage spans a period of ∼470 d since explosion. The X-ray emission softens with time, and we characterize the X-ray luminosity evolution as L X ∝ t −0.4 . We use the observed X-ray luminosity to estimate a mass-loss rate for the progenitor star of ∼2 × 10−6 M⊙ yr−1 . The optical light curve shows a pronounced plateau lasting for about 110 d. Temporal evolution of photospheric radius and colour temperature during the plateau phase is determined by making blackbody fits. We estimate the ejected mass of 56 Ni to be 0.06 ± 0.03 M⊙ . Using the expressions of Litvinova & Nadëzhin we estimate an explosion energy of (0.98 ± 0.25) × 1051 erg . We also present a single epoch radio observation of SN 2004et. We compare this with the predictions of the model proposed by Chevalier, Fransson & Nymark. These multiwavelength studies suggest a main-sequence progenitor mass of ∼20 M⊙ for SN 2004et. 相似文献
19.
We present the X-ray light curve in the 0.2–2.4 keV band based on fiveROSAT observations of SN1978K in NGC 1313. The X-ray emission is believed to arise from the interaction of the reverse shock and the expanding debris from the supernova. The reverse shock becomes established after the outgoing shock runs into circumstellar matter. 相似文献
20.
D. Yu. Tsvetkov P. V. Balanutsa V. M. Lipunov I. M. Volkov O. A. Tuchin I. P. Kudelina M. V. Pruzhinskaya E. S. Gorbovskoy V. G. Kornilov A. A. Belinskii N. V. Tyurina V. V. Yurkov Yu. P. Sergienko A. G. Tlatov A. V. Parkhomenko D. V. Dormidontov V. A. Senik V. V. Krushinskii 《Astronomy Letters》2011,37(11):775-782
We present the results of our UBVRI CCD photometry for the second brightest supernova of 2009, SN 2009nr, discovered during a sky survey with the telescopes of the MASTER robotic network. Its light and color curves and bolometric light curves have been constructed. The light-curve parameters and the maximum luminosity have been determined. SN 2009nr is shown to be similar in light-curve shape and maximum luminosity to SN 1991T, which is the prototype of the class of supernovae Ia with an enhanced luminosity. SN 2009nr exploded far from the center of the spiral galaxy UGC 8255 and most likely belongs to its old halo population. We hypothesize that this explosion is a consequence of the merger of white dwarfs. 相似文献