• 천문학회지
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• 제38권2호
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• pp.211-214
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• 2005

We performed a spatially resolved spectroscopic study of the thermal composite supernova remnant 3C 391 by the Chandra observation. Broad- and narrow-band X-ray images show a southeast-northwest elongated morphology and unveil a highly clumpy structure of the remnant. The spectral analysis for. the small-scale features indicates normal metal abundance and uniform temperature for the interior gas. The properties of the hot gas are largely in agreement with the cloudlet evaporation model as a main mechanism for the 'thermal composite' X-ray appearance, though radiative rim and thermal conduction may also be effective. An unresolved X-ray source, with a power-law spectrum, is observed on the northwest border. The equivalent width images reveal a faint finger-like protrusion in Si and S lines out of the southwest radio border.

• 천문학회지
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• 제38권4호
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• pp.385-414
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• 2005

We have searched for infrared emission from supernova remnants (SNRs) included in the Spitzer Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) field. At the positions of 100 known SNRs, we made 3.6, 4.5, 5.8, and $8.0{\mu}m$ band images covering the radio continuum emitting area of each remnant. In-depth examinations of four band images based on the radio continuum images of SNRs result in the identification of sixteen infrared SNRs in the GLIMPSE field. Eight SNRs show distinct infrared emission in nearly all the four bands, and the other eight SNRs are visible in more than one band. We present four band images for all identified SNRs, and RGB-color images for the first eight SNRs. These images are the first high resolution (<2') images with comparative resolution of the radio continuum for SNRs detected in the mid-infrared region. The images typically show filamentary emission along the radio enhanced SNR boundaries. Most SNRs are well identified in the 4.5 and $5.8{\mu}m$ bands. We give a brief description of the infrared features of the identified SNRs.

• 천문학회지
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• 제40권4호
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• pp.161-164
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• 2007

We calculate the evolution of multiple supernova (SN) explosions inside a pre-exiting bubble blown up by winds from massive stars, using one-dimensional hydrodynamic simulations including radiative cooling and thermal conduction effects. First, the development of the wind bubble driven by collective winds from multiple stars during the main sequence is calculated. Then multiple SN explosion is loaded at the center of the bubble and the evolution of the SN remnant is followed for $10^6$ years. We find the size and mass of the SN-driven shell depend on the structure of the pre-existing wind bubble as well as the total SN explosion energy. Most of the explosion energy is lost via radiative cooling, while about 10% remains as kinetic energy and less than 10% as thermal energy of the expanding bubble shell. Thus the photoionization and heating by diffuse radiation emitted by the shock heated gas is the most dominant form of SN feedback into the surrounding interstellar medium.

• 천문학회보
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• 제43권1호
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• pp.62.3-63
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• 2018

Trends of Type Ia supernova (SN Ia) luminosities with the properties of host galaxies are important to study the underlying physics for an SN progenitor system and explosion mechanism. In the YONSEI SN catalog, we have a sample of ~600 SN and host data in the wider redshift range, and two independent light-curve models, SALT2 and MLCS2k2. From this catalog, here we present that SNe Ia in low-mass, globally and locally star-forming environments are fainter than those in high-mass, globally and locally passive environments, after light-curve shape and color or extinction corrections. Our results are then compared to previous studies, and show consistent results.

• 천문학회지
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• 제37권4호
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• pp.223-224
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• 2004

The Tycho supernova remnant (SNR), as one of the few historical SNRs, has been widely studied in various wavebands and previous observations have shown evidence that Tycho is interacting with a dense ambient medium toward the northeast direction, In this paper, we report our high-resolution (16') $^{12}CO$ observation of the remnant using the Nobeyama 45m radio telescope. The Nobeyama data shows that a large molecular cloud surrounds the SNR along the northeastern boundary. We suggest that the Tycho SNR and the molecular cloud are both located in the Perseus arm and that the dense medium interacting with the SNR is possibly the molecular cloud. We also discuss the possible connection between the molecular cloud and the Balmer-dominated optical filaments, and suggest that the preshock gas may be accelerated within the cosmic ray and/or fast neutral precursor.

• 천문학회지
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• 제6권1호
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• pp.19-28
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• 1973

16세기 후반에서 17세기 초에 우리나라에서 관측된 4개의 초신성(Tycho Supernova, Kepler Supernova, Cassiopeia Nova 및 Cassiopeia A)의 기록은 세계 어느 나라 천문관측기록 보다 더 자세히, 또 더 정확히 표시되어 있다. 특히 Kepler Supernova의 기록은 우리나라 이조 왕조실록에 가장 자세하게 실려있다. 위치뿐만 아니라 밝기, 관측시간 및 관측상태를 낱낱이 표기한 이 관측치로부터 다음과 같은 광도곡선상의 특징을 알아낼 수 있다. 1. 준극대광도(Pre-max-halt)는 1604년 10월 20일부터 10월 26일 사이 2. 극대광도(Maximum Luminosity)는 1604년 10월 29일부터 11월6일 사이 3. 천이과정(Transition)은 아마도 1604년 11월 28일부터 1604년 12월 26일 사이에 있었을 것이다.

• 천문학회지
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• 제37권2호
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• pp.61-77
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• 2004

We have searched for HI 21 cm line emission from shocked atomic gas associated with southern supernova remnants (SNRs) using data from the Southern Galactic Plane Survey. Among the 97 sources studied, we have detected 10 SNRs with high-velocity HI emission confined to the SNR. The large velocity and the spatial confinement suggest that the emission is likely from the gas accelerated by the SN blast wave. We also detected 22 SNRs which show HI emission significantly brighter than the surrounding regions over a wide ($>10 km\;s^{-1}$) velocity interval. The association with these SNRs is less certain. We present the parameters and maps of the excess emission in these SNRs. We discuss in some detail the ten individual SNRs with associated high-velocity HI emission.

• 천문학논총
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• 제30권2호
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• pp.149-153
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• 2015

We present an ongoing study of the complete sample of supernova remnants (SNRs) and candidates in the Magellanic Clouds. 108 objects in both Clouds are considered to be either SNR or reliable candidates. This represents the most complete sample of all known SNRs in any galaxy. It therefore allows us to study SNR population properties such as the age-diameter (Age-D) relation. Here, we show that this Age-D relation is strongly dependant on the local environment in which SNRs are residing.

• 천문학회보
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• 제37권2호
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• pp.64-64
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• 2012

Supernova remnants (SNRs) are beautiful and diverse. Individual SNRs have their own distinctive features. The morphology and physical characteristics of young SNRs result from the interaction of supernova (SN) ejecta with circumstellar medium, while those of old SNRs result from the interaction of SN blast wave with the interstellar medium. The diversity of SNRs reflects different types of SN and the broad physical conditions in their environments, which are ultimately related to the formation and evolutionary history of progenitor stars. The importance of SNe and SNRs as the sources of heavy elements, cosmic rays, dusts, hot coronal gases, and interstellar turbulences depends on their types and environments. In this talk, I discuss the connections among SNRs, SNe, and their progenitors, and the consequences on the characteristics and astrophysical roles of SNRs.

• 천문학논총
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• 제5권1호
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• pp.85-94
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• 1990

Wangjo Silok, the official chronicle of Lee Dynasty, carries 131 records on the Kepler Supernova 1604; all of them are given in the present report. Among them 112 records are detailed descriptions about the observed brightness variation over the period from October 13, 1604 (the 37th year of King Sunjo) to April 23, 1605. On July 14, 1605, an addendum is given as a final assessment of the guest star incidence. Since the apparent brightness, size and position are carefully described as compared to bright planets and stars, these records are ideal for retrieving light curve of the Kepler Supernova over the seven month period. Simple procedures are suggested for the derivation of light curve.