X-rays from Massive Star Fo ｒ ming Region (YSO)

？Sgr B2 、 Arches, Mon R2

Herbig Ae/Be stars

Sgr B2 　 Cluster of Massive Stars.No10: Associated to UC HII regionsNo13: No association to UC HII regions

No13 　 No10

ｋ T ～ 10(4.1-30)NH ～ 4.0(1.9-8.8)Lx~ 13 x1032erg/s

ｋ T ～ 4.8(> 1.1)NH ～ 4.0(2.4-7.3)10 ２３

Lx~8 x1032 erg/s

Total Lx~1033 erg/s 　 Each Lx ～ 1032 erg/sNo10: Strong iron line (Abundance ~5M◎)No13: Weak iron line

Arches Cluster● IR ；　 No21, 23, 26: 　　 High mass (Initial mass > 100M◎)● Radio ； AR1, 4

Name kT NH L x (keV) (1023Hcm-2) (1033 erg s-1)

26 2.4(1.3-5.6) 6.9(4.5-11.2) 2.8(2.3-3.4)

21(AR4) 1.3(0.6-2.5) 9.3(5.6-15.5) 3.9(3.1-4.7)

23(AR1) 1.6(1.0-2.7) 9.9(6.514.8) 5.0(4.2-6.0)

Irradiation by the Arches X-rayTotal luminosity ~1035 ergs/s10 time larger than the present value. One possibility is that the Arches cluster may be brighter in the past.

Mon R2 Cloud

2.5 M◎

More massive than B

H-K

K

kT ～ 2 - 10 keV, Lx ～ 1031 erg/sRapid variability

Name kT NH 　　　　 Lx (keV) 　　　　　　 (1022Hcm-2) (1031erg/s)

IRS 1SW 　　 1.9(1.3-2.8) 4.7(3.5-6.4) 1 (0.6-2.0)aS 2.6(1.6-6.2) 6.0(4.0-9.2) 0.6(0.4-1.6)

IRS 2 10.9( > 2.0) 9.1(5.7-17) 　 0.6(0.5-2.0)

X-ray Properties with Chandra

ASCA detection of Herbig Ae/Be Stars

Detection rate ~40%(>1030 ergs/s)

Temperature vs Wind Velocity of Herbig Ae/Be

2~3keV

MWC 297 : O9 - B1.5NH ～ 2.4×1022 (Av =10 agree with optical) 　　　　 Temperature ExcursionkT= 2.7keV 6.7keV 3.2 keV

2.7keV6.7keV

3.2keV

　　　 Temperature Excursion of 　　　 Individual Herbig Ae/Be 　　　　 Quiescent (●), Flare (□), Decay ( )△

Unified View of X-ray emission from Stars

Ｕｎｉｆｉ ed Picture of X-rays From Stars106 yrs