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Summary(3)-- Dynamics in the universe --
T. Ohashi (Tokyo Metropolitan U) 1. Instrumentation for dynamics 2. Cluster hard X-rays3. X-ray cavities4. Dark matter dynamics 5. Large-scale features
Science with NeXT
Strong gravity(BH, Darkmatter)Collision, Explosion, Jets, Magnetic fields etc
Gas motion, Shocks
Particle acceleration
Spectroscopy Microcalorimeter
Hard X-ray image Supermirror + imaging detector
-ray spectrum Compton telescope
Gas heating
High-energy universe
X-rays
-rays
Doppler spectroscopy Microcalorimeter
Cosmic rays
Global view of dynamical processes in the universe
Emission lines and Doppler spectroscopy
12 eV
Energy resolution of SXS E~7 eV (or better) Fe-K line complex resolved into resonance, intercombinatio
n, forbidden lines Gas motion with v ~ 100 km s-1 resolved
LHard ~ 1043 erg s-1 is reported from about 10 clusters
Merger systems tend to show hard X-ray emission
The detection is still controversial.Coma cluster(Fusco-Femiano et al 04 ⇔ Rossetti and Molendi 04)
Cluster hard X-rays
Nevalainen et al. 04
Hard X-rays from 14 clusters
Thermal
Cluster radio halos and relics
A3667: Radio relic
1045 1046Lx
(h=0.5)
Ensslin and Roettgering 02
1042
1041
LRadio
(erg/s)
Feretti astro-ph/0406090
=3 GHz
Expected hard X-ray luminosity
Observed data → LRadio~1041-42 erg s-1
if B = 3 G, then uB ~ uph ~ 0.3 eV cm-3
→ sensitivity of LHard ~ 1041-42 erg s-1 is necessary to explore inverse Compton emission
This is about 100 times higher sensitivity, achievable with the supermirror instrument
If protons carry 100 times more energy than electrons ( magnetic energy density), then non-thermal energy is a large fraction in clusters (equivalent to 1043-44 erg s-
1)
ph
B
IC
syn
u
u
L
L
L
L
X-Hard
RadioMicrowave background
X-ray CavitiesHCG62 (Chandra):Morita et al. 06
“Ghost cavity”
MS0735.6+7421 (z=0.22)McNamara et al. 05
Hot gas displaced by radio lobesGhost cavities are X-ray cavities without radio lobes nor radio galaxy
deviation
Non-thermal pressure
HCG62k/f
k = Ratio of proton/electron energy density
f = filling factor (~1)
Required energy density
>> u(magnetic field + electrons)
Large variation of k All protons or extremely
hot gas? Dunn et al. 05
Pressure to match gas pressure
Dark matter blobs
Gas Dark Matter
(z=0)
Cluster simulation: Eke et al. 98
Galaxy group simulation:Klypin et al. 99
Simulation under CDM scenario
Dark matter blobs are produced
In local group, only ~1/10 are detected as satellite galaxies
Blob velocity (groups): v = 100-1000 km s-1
Motion of dark matter blobs
1E0657-56: Markevitch et al. 04
Weak lens mass (DM travels forward)
Evrard 1990 (line = velocity)
DM particles/blobs continue to move even after gas is relaxed
Dark matter blobs may carry significant fraction of energy
Gas
Darkmatt
er
DM blobs may contribute to acceleration
Particle collision with DM blobs can cause Statistical Fermi acceleration
It is possible to accelerate particles within life of clusters
y1024
1 9coll
2
acc
tVc
t
(V = 2000 km s-1, tcoll = 100 kpc/c = 1013 s)
Dark Matterblob
Particle
V
Intracluster space
Pointing vs survey
Narrow field, high sensitivity: NeXT, Con-X, Xeus
Wide field, survey: eROSITA, MAXI, DIOS Only a few % of the whole sky covered with
CCD resolution Truly large scale structures: cosmic web, G
alactic hot gas, cluster survey etc
Dynamics of galactic hot gas
Dynamics of hot galactic ISM: Galactic fountain
OVII
Snowden et al. 95, ApJ 454, 643
Inoue et al. 79, ApJ 227, L85
ROSAT map
GSPC spectrum
Suzaku to NeXT decadeLow background and wide-band sensitivity
Detection of non-thermal emission from bright objects
First image of non-thermal emission with >100 times higher sensitivity
Gas dynamics through X-ray spectroscopy, with low background soft -ray detectors
Science of on-thermal universe will be much advanced
Suzaku
NeXT
+ Wide field mission for complementary science
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