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        <title>Daiphys Tech Portal - astro</title>
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       <dc:date>2026-04-30T16:30:33+00:00</dc:date>
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        <dc:date>2022-12-16T05:39:23+00:00</dc:date>
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        <title>Accretion Disk</title>
        <link>https://www.daiphys.com/portal/astro/accretion.html?rev=1671169163&amp;do=diff</link>
        <description>Accretion Disk

Reynolds Number

Reynolds = Inertia Fources / Viscous Fources = FlowLength * FlowVelo / Viscosity


Reynolds &gt;&gt; 1.00 :


	*  Viscosity is dynamically unimportant
	*  Viscosity plays essentially no role
	*  TLUSTY Viscosity = sqrt(GMR) / Reynolds</description>
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        <dc:date>2022-12-16T06:03:17+00:00</dc:date>
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        <title>Bremsstrahlung</title>
        <link>https://www.daiphys.com/portal/astro/brems.html?rev=1671170597&amp;do=diff</link>
        <description>Bremsstrahlung

電子の加速とショック

加速する電子のエネルギー分布はべき関数の形になるという経験則(?)がある

スペクトルがベキ関数の形をする場合はだいたい加速が起きたと考えられる$\sim$</description>
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        <dc:date>2022-12-14T15:22:19+00:00</dc:date>
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        <title>Constellation</title>
        <link>https://www.daiphys.com/portal/astro/constellation.html?rev=1671031339&amp;do=diff</link>
        <description>Constellation
	Abbreviation		Constellation		Genitive		日本名		English Name		And		Andromeda		Andromedae		アンドロメダ座		Andromeda		Ant		Antlia		Antliae		ポンプ座		AirPump		Aps		Apus		Apodis		ふうちょう座		BirdofParadise		Aqr		Aquarius</description>
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        <dc:date>2022-12-16T06:18:01+00:00</dc:date>
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        <title>Eddington Limit</title>
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        <description>Eddington Limit

Basics

質量から求まる

それ以上に明るくなると輻射圧で星の大気が飛ばされてしまう

恒常的に限界より明るいケースは難しいがトランジェントなら問題ない


重力と輻射圧の釣り合い
$\Sigma_{T}$$c$$L_{edd}$$\pi{}r^{2}$$GMm_{H}$$r^{2}$$\Sigma_{T}$$m_{H}$$c$$L_{edd}$$\pi{}cGM$$k_{T}$$k_{T}$$L_{edd}$$\pi{}c^{3}$$k_{T}$$GM_{\odot}$$/$$c^2$$M$$/$$M_{\odot}$$\times$$^{38}$$M$$/$$M_{\odot}$</description>
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        <title>Extinction</title>
        <link>https://www.daiphys.com/portal/astro/extinction.html?rev=1671171521&amp;do=diff</link>
        <description>Extinction

Galactic Value

E(B-V) = 0.071 (Shlegel et al. 1998)


E(B-V) to Av

Av = 3.1 E(B-V)


Nh vs Av

$N_{\rm{H,ISM}}$/$A_{V,\rm{ISM}} = 1.79 $\pm$ 0.03 \times 10^{21}$ cm$^{-2}$ mag$^{-1}$ (Predehl &amp; Schmitt 1995)

$N_{\rm{H,ISM}}$/$A_{V,\rm{ISM}} = 1.89 \times 10^{21}$ cm$^{-2}$ mag$^{-1}$ (Osterbrock D.E. 1989)

$N_{\rm{H,ISM}}$/$A_{V,\rm{ISM}} = 2.22 $\pm$ 0.15 \times 10^{21}$ cm$^{-2}$ mag$^{-1}$ (Gorenstein 1975)

$N_{\rm{H,ISM}}$/$A_{V,\rm{ISM}} = 2.31 $\pm$ 0.04 \times 10^{21}$ cm…</description>
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        <dc:date>2023-03-10T05:52:43+00:00</dc:date>
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        <title>Astro</title>
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        <description>Astro


	* Accretion Disk
	* Bremsstrahlung
	* Constellation
	* Eddington Limit
	* Extinction
	* Interferometer
	* Luminosity
	* Observatory
	* Plasma
	* Tools</description>
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        <dc:date>2022-12-16T06:25:12+00:00</dc:date>
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        <title>Interferometer</title>
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        <description>Interferometer

干渉望遠鏡の原理

小さい領域からの光は干渉しやすく、大きい領域だと干渉しにくい

一方で、干渉の度合いは口径で決まる空間周波数の関数に対応する

つまり干渉しやすい光源の距離は周期的な関数で表すことができる</description>
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        <dc:date>2022-12-16T07:25:44+00:00</dc:date>
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        <title>Luminosity</title>
        <link>https://www.daiphys.com/portal/astro/luminosity.html?rev=1671175544&amp;do=diff</link>
        <description>Luminosity

Basics
 Symbol  Name  日本名  Unit  L  Luminosity  光度  erg s-1  F  Flux  流束  erg s-1 cm-2  I  Intensity  強度  erg s-1 cm-2 sr-1  Fν  Flux Density  流束密度  erg s-1 cm-2 Hz-1, Jy  Fλ    erg s-1 cm-2 μm-1  Iν  Surface Brightness $\pi{}$$^{2}$</description>
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        <dc:date>2022-12-16T06:26:07+00:00</dc:date>
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        <title>Plasma</title>
        <link>https://www.daiphys.com/portal/astro/plasma.html?rev=1671171967&amp;do=diff</link>
        <description>Plasma

プラズマについて

荷電粒子と中性粒子によって構成され、集団的振る舞いをする準中性気体

もう少し簡単にいえば、電離によって生じた荷電粒子を含む気体のこと

電離する過程は一般的に(1)放電電離、(2)熱電離、(3)光電離と3種類ある$\xi$$L_{x}$$n_{e}$$r$</description>
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