JAXA 229 8510 3 1 1, SRON, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands e-mail: takei@astro.isas.jaxa.jp/y.takei@sron.nl (warm-hot intergalactic medium; WHIM) 1 1. WMAP 2, 3 137 1 1) 96 4 (z 1) 2 4 2 3 2 3 LCDM 3 (warm-hot intergalactic medium; WHIM) (warm-hot) X hot gas 100 8 391
1 1 50 h 1 70 Mpc; 2 1 a warm gas 10 3 1, 2 2 OVI (O 5 ), OVII (O 6 ), NeIX (Ne 8 ) 392 2007 8
OVI / OVII, NeIX / X / 2. 1 FUSE (Far Ultraviolet Spectroscopic Explorer) 40 OVI 1032.9 AÕ 1037.6 AÕ OVI 30 OVI 30 OVI OVI 1/10 4, 5 OVI 1/10 OVII NeIX X / X X Chanda, XMM-Newton FUSE 1, 2 Nicastro Mrk421 6) Mrk421 Chandra LETG 0.011 0.027 OVII, NVII 0.027 NVI, CVI 5.8s, 8.9s 2.7 3.8 1.9 XMM-Newton 7) XMM-Newton Nicastro Kaastra Nicastro 94 1.9s 8) Nicastro 100 100 8 393
100 6 Kaastra Nicastro 3. 2 2 1 CCD X CCD CCD Kaastra OVII, OVIII 9) Finoguenov Coma-11 OVII, OVIII 20 Mpc 10) 11 OVII, OVIII OVII, OVIII OVII, OVIII CCD 0.06 12) 4. 1: Nicastro 394 2007 8
3 NeIX CCD CCD 4 NeIX, OVII, OVIII OVII, OVIII NeIX OVII, OVIII NeIX XMM-Newton CCD (452 ks) XComae 100 8 395
OVII, OVIII, NeIX, NeX NeIX 3 99.2 90 OVII, NeX, OVIII 5s 99.2 2.7s NeIX XComae CCD OVII, OVIII, NeIX 0.023 CCD 4 OVII, OVIII, NeIX OVII, OVIII NeIX NeIX NeIX 200 600 (0.2 8) 10 5 cm 2 d 10 d 400 6 1 3 Mpc 2.4 96.4 2.1s OVIII d 220 13, 14 5. 2: Nicastro Mrk 421 CCD 396 2007 8
5 A2218 OVII OVIII Coma- 11 10),Sérsic 159-03, MKW 3S, A2052 9) CCD A2218 0.178 15) A2218 1keV 2005 X 0.5 kev A2218 XMM-Newton 5 A2218 OVII, OVIII 2s 0.2 kev A2218 270 (d 270) 6 d 6 d 16) d 100 8 397
d 10 d 100 16) d 6 6. 21 X 2004 2005 Astro-E2 XRS CCD 20 XRS 2007 X NeXT X 1 100 cm 2 1, 2 2 3 DIOS 17) 3 18) 22) 5 CCD CCD 398 2007 8
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