black holes and neutron stars in extp era
TRANSCRIPT
Black holes and Neutron stars in eXTP era
Zhang Shu
(on behalf of the eXTP science team) Institute of High Energy Physics
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eXTP: an ambitious mission in future
Missions crowed but short of:
large area, polarization.
eXTP: collaboration of China and Europe
Selected for Phase 0/A in 2011,
expected launch in around 2023.
eXTP satellite
XTP(2009-2014) eXTP(since 2014)
payload SFA 11 arrays:focus length 4.5m,Diameter 450 mm,SDD Energy band:0.5-20 keV FOV:12 arcmin Time resolution:10 us Energy resolution: 180eV@6keV Angular resolution:1arcmin Sensitivity:0.16uCrab(104s) Effective are:6000cm2@6keV
LAD 40 arrays SDD Energy band:2-30 keV FOV:1dg Time resolution:2us Energy resolution:200eV @ 6keV Augular resolution:1 dg Sensitivity:0.01uCrab(104s) Effective area:3m2@6keV
WFM 3 arrays,SDD Energy band:2-50 keV FOV:1.33PI Time resolution:2 us Energy resolution:300eV@6keV Angular resolution:4.5 arcmin Sensitivity:3uCrab(2x104s) Effective area:170cm2@6keV
PFA, 2 arrays:focus length 4.5m,diameter 450mm Energy band:2-10 keV FOV:12 arcmin Time resolution:500us Energy resolution: 1.8keV@6keV Angular resolution:15arcsec Sensitivity:5 uCrab(104s) Effective area:250cm2@2keV
Key properties of eXTP
Effective area ~0.6 m2 @6keV ,~0.9 m2 @0.5-2 keV(SFA) ~3 m2 @6keV (LAD) Time resolution 2-10 μs Energy resolution ~200 eV @ 6keV (LAD, SFA) Polarization MDP~1.6% (106 photons, 1 Crab under 104 s)
Powerful two eyes in energy and time domains : spectrum and timing Unique third eye in polarization domain : emission geometry and magnetism
Powers in eXTP: spectral-timing ; timing-polarimetry
Road map 2010-2030: unique and powerful eXTP
eXTP effective area and comparisons with other telescopes.
Key Sciences of eXTP:
One singularity
(Black hole)
Two stars
(Neutron star and quark star)
Three extremes
(gravity, density, magnetism)
Via observing BH and NS systems
eXTP will answer:
are the fundamental physical laws universal?
The fundamentals/pillars of modern physics: 1, General relativity theory: large scale interaction valid under extreme in gravity? 2, Quantum chromodynamics theory strong interaction, quark and gluon scale valid under extreme in matter density? 3, Quantum electrodynamics theory interaction of electron and photon valid under extreme in magnetic field?
1, what are the condition for planet formation and the emergency of life? 2, how does the solar system work? 3, what are the fundamental physical laws of the universe? (eXTP, LOFT, Nicer) 4, how did the universe originate and what is it made of? (Athena+)
Core science:
BH and strong field gravity (SFG)
The gravity potential in the vicinity of a
black hole is 4 magnitudes higher than
those used for testing GR currently.
Astronomical lab:
Measure the reflection on the
accretion disk and the
relativistically broadened Fe
line.
Core science : BH and SFG
eXTP spectral-timing:
Broadened Fe line
eXTP spectral-timing: Disk reverberation
eXTP spectral-timing: QPO
eXTP timing-polarimetry: QPO and polarization
Core science : BH and SFG
0
5E-5
1E-4
1.5E-4
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Ph
oto
n/c
m2/s
/ke
V
Energy (keV)
a=0.0a=0.5a=0.9
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1E-12 1E-11
Fitted spin value (with 90% confidence rang
2-10keV Flux (ergs/s/cm2)
xtp lfa(100eV)
xmm pn(100eV)
xtp joint(100eV)xtp lfa(200eV)
xmm pn(200eV)
xtp joint(200eV)
model value
BH spin and broad Fe line in AGN led by:SFA Typical exposure :1 Ms
BH spin and broad Fe line in XRB: led by : LAD Typical exposure: a few hundred seconds.
Core science : BH and SFG
led by:LAD Typical exposure a few tens seconds. Observational target: XRB
Space-time dragging effect predicted by GR: precession of central corona and QPO.
Spectral ratio of QPO rising and fall parts.
Core science : BH and SFG
XRB hot spot and the
dynamically
broadened Fe :
Typical exposure:a
few hundreds seconds.
led by:LAD
AGN hot spot and the dynamically broadened Fe: Typical exposure: less than 10 ks. Led by:SFA
Hot spot in inner disk
Periodical Fe line modification
Core science : BH and SFG
Reverberation mapping: AGN, typical exposure 1 Ms, led by SFA+LAD XRB, typical exposure 100 ks, led by LAD.
AGN reverberation mapping
XRB reverberation
mapping
Measure the absolute distance from BH
Core science : BH and SFG
GR predicts three
frequencies intrinsic to
accretion disk:
orbital cycle
Radial epicycle
Periastron precession
QPO measurement by eXTP: Observational target: XRB Typical exposure:10 ks Led by LAD
Core science : BH and SFG
Corona precession predicted by GR: Polarization measurement provides an independent test.
Observational target: XRB Typical exposure:50 ks Led by:PFA and LAD
Core science : BH and SFG
The space time around
spinning BH is Kerr metric?
Strong correlation between the
estimate of the spin and
possible deviations from the
Kerr solution?
Observational target:CygX-1 exposure:100ks Led by:LAD and SFA
eXTP simulation on CygX-1: exposure 100 ks, correlation between the deformation parameter of the metric and the BH spin. (provided by Prof. Cosimo Bambi group)
Core science: NS and dense matter (DM)
Requirement to NS radius measurement: a precision of 5-10%
Core science: NS and DM
Pulse profile of hot spot on surface of NS. Measure parameters: M,R,I and θ. Input: ms pulsar: f>200 Hz Four obs. variables: flux rms, color rms, C, and ∆φ well understood emission mechanism and the light curve
NS and DM: Observational targets
1, Burst oscillation ms pulsar: 6 sources with spin frequency > 200Hz, typical exposure <a few hundreds ks to 1 Ms, led by LAD Spectrum: hot spot with black body, temperature ~ 2 keV 2, Rotational powered ms pulsar: source: PSRJ0437-4715, spin frequency: 174 Hz typical exposure: 300ks led by SFA Spectrum: hot spot with black body, temperature ~0.1-0.3 keV Mass and inclination angle: measured by radio via Shapiro delay: 1.76+-0.2 solar mass, 137.6 dg (Verbiest et al., 2008)
NS and DM: Observational targets
3, Accretion X-ray ms pulsar: 12 sources with spin frequency > 200Hz, (Patruno et al. 2013) typical exposure : depends on the strength of outburst,~ a few hundreds ks, led by LAD,SFA and PFA Spectrum: black body and thermal Comptonization (hot spot + corona)
XMM and XTE observation on the outburst of XTEJ1751-305 in 2002. Seed photons of the hot spot with both low/high temperatures can fit the spectrum.(Gierlinski et al. 2005). Polarization measurement can help to discriminate between two models.
NS and DM: Observational targets
Mass-shedding frequency to constrain NS mass and radius. target:XRB in outburst Exposure: < 1ks Led by:LAD
Core science:
magnetar and strong magnetic field
Magnetar: AXP/SGR are a special NS type. With magnetic field larger than 1014 G.
Ideal lab for testing QED predication.
QED predication of vacuum birefringence effect. Needs magnetic field > 1013 G
The largest magnetic field produced on earth: <106 G
Core science:
magnetar and strong magnetic field
0 0.5 1
Flux 10-10 erg
/cm
2/s
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Linear Polarization (%)
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0 0.5 1Polarization A
ngle (deg)
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Flux 10-10 erg
/cm
2/s
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P hase0 0.5 1
Linear Polarization (%)
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0 0.5 1Polarization Angle (deg)
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P hase0 0.5 1
Flux 10-10 erg
/cm
2/s
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0.35
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P hase0 0.5 1
Linear Polariza
tion (%)
50
60
70
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100
P hase0 0.5 1
Polariza
tion A
ngle (deg)
90
100
QED prediction: vacuum birefringence target:AXP 1RXS J170849.0-400910 exposure:1.3 MS Led by:PFA,SFA,LAD
Simulation on 1RXS J170849.0-400910 at 2-10 keV: X-ray flux、polarization degree, polarization angle. Input: latitude of the hot spot 30°(red), 75° (black), Inclination angle 60°, vacuum birefringence effect accounted. Theoretical model: Taverna et al., 2014.
With birefringence effect
Without birefringence effect.
More landscapes of astrophysics explored by eXTP 1, The entire outbursts of XRBs 2, accretion physics 3, Extremely violent events (bursts) : gamma-ray burst, type-I burst, AXP and SGR 4, Diffuse emission, SNR 5, X-ray polarimetry
New science window: X-ray polarimetry
Accreting black holes
• Black hole binaries: accretion geometry, BH spin
• Blazars: emission mechanism, jet composition?
• Radio quiet AGNs: corona geometry, unification model
Strong magnetism
• Rotation-powered: acceleration regions
• PWN: B-field
• accretion powered pulsars: accretion and emission geometry
• Shell-type SNRs: particle acceleration, B-field
Fundamental physics
• GR effect: space curvature, space-time frame dragging
• QED: vacuum polarization
冯骅,XTP研讨会,西峰山庄
Polar cap model Slot gap model Outer gap model
Black hole and neutron star in eXTP era
They become the messengers to us for probing the
fundamental physics.
Excellent/unprecedented three eyes of eXTP allow for working in synergy
on the tiny/fine structures residing in: the spectral domain,
the timing domain and the polarimetry domain.
Thank you !