• Title/Summary/Keyword: black brightness

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Positron Annihilation Spectroscopy of Active Galactic Nuclei

  • Doikov, Dmytry N.;Yushchenko, Alexander V.;Jeong, Yeuncheol
    • Journal of Astronomy and Space Sciences
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    • v.36 no.1
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    • pp.21-33
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    • 2019
  • This paper focuses on the interpretation of radiation fluxes from active galactic nuclei. The advantage of positron annihilation spectroscopy over other methods of spectral diagnostics of active galactic nuclei (therefore AGN) is demonstrated. A relationship between regular and random components in both bolometric and spectral composition of fluxes of quanta and particles generated in AGN is found. We consider their diffuse component separately and also detect radiative feedback after the passage of high-velocity cosmic rays and hard quanta through gas-and-dust aggregates surrounding massive black holes in AGN. The motion of relativistic positrons and electrons in such complex systems produces secondary radiation throughout the whole investigated region of active galactic nuclei in form of cylinder with radius R= 400-1000 pc and height H=200-400 pc, thus causing their visible luminescence across all spectral bands. We obtain radiation and electron energy distribution functions depending on the spatial distribution of the investigated bulk of matter in AGN. Radiation luminescence of the non-central part of AGN is a response to the effects of particles and quanta falling from its center created by atoms, molecules and dust of its diffuse component. The cross-sections for the single-photon annihilation of positrons of different energies with atoms in these active galactic nuclei are determined. For the first time we use the data on the change in chemical composition due to spallation reactions induced by high-energy particles. We establish or define more accurately how the energies of the incident positron, emitted ${\gamma}-quantum$ and recoiling nucleus correlate with the atomic number and weight of the target nucleus. For light elements, we provide detailed tables of all indicated parameters. A new criterion is proposed, based on the use of the ratio of the fluxes of ${\gamma}-quanta$ formed in one- and two-photon annihilation of positrons in a diffuse medium. It is concluded that, as is the case in young supernova remnants, the two-photon annihilation tends to occur in solid-state grains as a result of active loss of kinetic energy of positrons due to ionisation down to thermal energy of free electrons. The single-photon annihilation of positrons manifests itself in the gas component of active galactic nuclei. Such annihilation occurs as interaction between positrons and K-shell electrons; hence, it is suitable for identification of the chemical state of substances comprising the gas component of the investigated media. Specific physical media producing high fluxes of positrons are discussed; it allowed a significant reduction in the number of reaction channels generating positrons. We estimate the brightness distribution in the ${\gamma}-ray$ spectra of the gas-and-dust media through which positron fluxes travel with the energy range similar to that recorded by the Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics (PAMELA) research module. Based on the results of our calculations, we analyse the reasons for such a high power of positrons to penetrate through gas-and-dust aggregates. The energy loss of positrons by ionisation is compared to the production of secondary positrons by high-energy cosmic rays in order to determine the depth of their penetration into gas-and-dust aggregations clustered in active galactic nuclei. The relationship between the energy of ${\gamma}-quanta$ emitted upon the single-photon annihilation and the energy of incident electrons is established. The obtained cross sections for positron interactions with bound electrons of the diffuse component of the non-central, peripheral AGN regions allowed us to obtain new spectroscopic characteristics of the atoms involved in single-photon annihilation.

A Study on Heart-Mind of Daesoon Thought from the Perspective of Neo-Confucianism: Focused on Numinous Emptiness, Wise-awakening, and Divine Beings (주자학으로 본 대순사상의 마음에 관한 연구 - 허령, 지각, 신명을 중심으로 -)

  • Choi, Chi-bong
    • Journal of the Daesoon Academy of Sciences
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    • v.31
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    • pp.237-269
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    • 2018
  • This study aims to look into Daesoon Thought from the perspective of Neo-Confucianism. Numinous emptiness (虛靈), wise-awakening (知覺), and divine beings (神明) in the Scripture of the Black Tortoise (Hyeonmu-gyeong) are often mentioned as characteristics of the mind in Neo-Confucianism. Accordingly, this research take up the 'Che-Yong (substance, 體 and function, 用)' of mind by classifying numinous emptiness as Origin-Substance (本體), wise-awaking as function, and divine beings as subjects. Numinous emptiness enables an individual to have been born with Li (理) of Taegeuk (太極), which is a mandate from Heaven and the nature of humanity; whereas one embodies spirit and brightness mind based on Origin-Substance. This numinous emptiness of mind is precisely the mind-spirit. Wise-awakening is a function of mind, which actually awakens numinous emptiness (理) and objects (氣). The mind which realizes the Li of Taegeuk as numinous emptiness is conscientiousness and can be taken as a Dao-Mind. The mind which desires objects refers to the Human Mind or a selfish motive. Such propensity in terms of wise-awakening determines the state of mind. One should reach the state of a quiet mind by wisely awakening through the scripture. Divine beings correspond to metaphysical Origin-Substance and physical objects respectively. In addition, they comprehend all and preside over wise-awakening as subjects. The subject recognizes wise-awakening and responds to it. Mind is a path traveled upon by divine beings as they enter and exit. In this regard, the human mind refers to the organ used by immanent deities, which accumulates physical senses, innermost mental processes, and awakened activities. Furthermore, Transcendental deities also come in and out through mental correspondence, leading to changes in one's physical constitution or personality. This paper focuses on the mind perceived in Daesoon Thought as follows: first, besides the existing spiritual perspective, the research takes a view on surveying numinous emptiness, wise-awakening, and divine beings in Neo-Confucianism. Secondly, the Che-Yong of mind is closely looked into by means of innate numinous emptiness as Che and wise-awakening as Yong. Lastly, the essence, energy, and divinity as well as spiritual soul and physical soul are mentioned according to the concept of an immanent deity. The paper also clarifies the fact that divine beings preside over the mind as subjects.