???~(1-10)?km

1
?????????????????
2004?1?20? ????????? ???

• ????
• ????????

2
??????

• ?????????????????
• ????????
• ??????????????
• ???????
• ??????/?????
• ??????
• ????????

3
?????????????????
4
???????
Ha
?? 1??

• 19??????
• ???????gt?????????
• ???(1-10)?km
• ??????
• 1029 - 1032erg
• (??10??1??)

???????
5
???????????????
6
???????????????????????!

• X???????(1keV)
• 200???
• 1000???????????

7
?????????????X?(1keV)
?????????
8
??????(SXT, 1keV? Tsuneta et al. 1992 )
electron temperature 107 K? electron
density10(10)cm(-3)
9
Plasmoid ejectionassociated with LDE flare
(Yohkoh/SXT)

• Plasmoid speed is about 300km/s

10
Coronal mass ejections (CME)(SOHO/LASCO)
Velocity 10-1000km/s?mass 10(15)-10(16)g
11
?????? vs ?????? ???

• ?? 1???? 1????
• ??? ? ?
• ???? ??? ??
• ?X?? ????? ?????

???????????? ??????!?
???????????OK
12
????????????????????X?????(Masuda et al. 1994
Nature)

• ????X??(1keV)
• ????X?(30keV)gt????????

??????1??
13
?????
X???? ????? ???

• ???????X????fast shock ??

14
?????????????????????
???????? 130-200km/s

• Ohyama and Shibata (1997,1998)
  ??????????????????????

15
?????????????(?????X?)

• ??????????
• ??????10?km
• ??10-
• 1000km/s

16
????????????????????????(????1995)

• ????

17
?????????
?? ?? (L) ?? (T) Alfven Time (TA) T/TA Mass ejection
???? (??????) (?????????) ????10?km 1?? ??? 30? 1000? 100 ??????
???? ?km???km ??? 1?? 1?30? 100 ????
18
????????

• ????(N??????(gtW)? W?????????)
• ??????????????

19
?????????????

• (a,b) ?????
• ????????
• ???????
• (c,d) ?????
• ????

????????
20
??Ha????(??????????1988)

• ?????? ?????? ??

21
?????

• ??????????(???????????)??????
  -?????????????????
• ?????????
• ??????
• ????

22

• Plasmoid starts to be ejected long before the
  impulsive phase.
• The largest plasmoid acceleration occurs during
  impulsve phase.
• (Ohyama and Shibata 1997)

23
Laboratory experiment(Ono et al. )
24
?????/??????
25
?????(proxima Cen)

• ???????????X???????????

26
??????(X?/????????1995)

• ??1??
• ????????????1????

27
??????????????????????????

• Yes
• ????????
• Emission Measure ( )
• vs Temperature ?????????
• (Shibata and Yokoyama 1999?2002)

28
???????? Emission Measure(EMn2V)
???(T)??????(n?????V??)(Feldman et al. 1995)
29
????????EM-T??
Feldmanet al. (1995) ??? Log-log plot
30
????????EM-T??
??????? (Shimizu 1995)
31
????????EM-T??
??????
???(Koyama et al. 1996, Tsuboiet al. 1997)
32
?????????????????

• ?????????????????????????(Yokoyama and Shibata
  1998?2001)

33
???? Emission Measure (Shibata and Yokoyama 1999)

• Emission Measure
• ???????????
• ???????????????

34
(No Transcript)
35
????(B)??
??????????????????????????
50-100G??
36
???????????
???????1???????? ????????????????
37
???????????????(??????? 1996)
38
????EM-T??HR??????!(Shibata and Yokoyama 2002)
??????
39
EM-T?????HR?

• ????? (???)
• ??????? (????)
• ?????? (????)
• ???? (??????)

40
?????
??????? F??
41
??????
???
???
42
??????????????
???gt???
43
????????????

• ???EM-T??,??HR???????????
• ???(???)??????????????
• ????????????
• EM-T????????????????????????/??????????????(?????
  ???????????????)????????????
• ????????????????/???????????????

44
??????
45
what is astrophysical jets ?
Protostellar jet (HH 1/2)
AGN jet (Cyg A)
Close binary system (SS433)
46
Characteristics of Astrophysical Jets
AGN Close binary system protostar
Central object Supermassiveblack hole Black hole or neutron star protostar
Jet length 1 Mpc 3 pc 0.3 pc
Jet velocity c 0.3c - c 100km/s
Escape velocity c 0.3c - c 100km/s
47
MHD model of astrophysical jets
Accelerate jets by magnetic field and rotation
Magnetic field line
jet
Centrifugal force
Accretion disk
Magnetic pressure
Protostar, black hole
Blandford-Payne 1982, Lovelace et al 1986,
Pudritz-Norman 1986, Uchida-Shibata 1985, Shu et
al. 1994,
48
First 2.5D simulation of MHD jets from
accretion disk (Shibata and Uchida 1986)
Magnetic field line
accretion disk
Time
Jet velocity Kepler velocity
49
MHD jet with bow shock(Kudoh et al. 2004, in
prep)
50
Main findings(from many MHD simulations in
1985-2002,especially by Kudoh, Shibata et al.)

• Velocity of jets Keplerian speed, but slowly
  increases with magnetic field strength
• Mass ejection rate is about 0.01 0.1 of mass
  accretion rate
• Jets and disks never reach steady state, but
  become very dynamic

51
Why can jets and disks never be in steady state
?
Because Magnetorotational Instability is so
powerful (Blabus and Hawley 1991)
Kudoh et al 2002
52
Mass Accretion Rate vs Mass Ejection Rate
Mass Ejection Rate
Mass Accretion Rate
time
53
General relativistic MHD simulation(Koide,
Shibata, Kudoh 1998,1999,2000)
Maximum Lorentz factor 2gtreal limit ?
54
MHD jets from Kerr hole magnetosphere

• Koide, Meier, Kudoh, Shibata (2000)

Koide et al. 2002 Science
55
????????
56
??????

• ???????????
• Klebesadel et al. (1973) by Vela satellites
• duration 10sec (1msec - 1000sec)

57
???????????

• ?????????????100keV-?MeV?????
• ???????X??????????
• 1??????
• ?????????????(??????.z1.6,z3.4,)
• (?????????????????????)??????10(53)-10(54)erg
• gt???????!

???????????????????????????????????????10(51)-10
52)erg? ?????? ???????MHD?????????
58
Central engine of gamma ray bursts ?
Binary neutron star merger model
Collapsar model
magnetar model
59
????????

• ???????????X??????? ???????
• duration 10sec (1msec - 1000sec)

?????
????????
60
??????

• ????/????duration
• ???????? log-normal ?? ?????????
  duration 10 100 sec (long burst)
• ????? power-law ?? ?????????
  ??????(????)???
• (?????????)

Log x
Log x
61
???????????????????GRB???????internal shock ??
??????????????????????????????!
Aoki et al. 2004 ?????? or energy??????????????
????? ??????????gt ??????????????
62
Flare/CME model of GRBs driven by magnetic
reconnection (Aoki, Yashiro, Shibata 2004)
Only large flares can produce large plasmoids
that have enough energy to escape from
magnetosphere of the central engine of a GRB (cf.
Negoro and Mineshige 2002)
63
??????

• ??????????????????? gt?????
• ????????????????
• ?????????????????????????????gtEM-T?
• ???????MHD???????MHD????disk ????????????????????
  ??
• ????????(??????)?????????????????
• ?????????????????????????? gt??????????