Current and Future Space X-ray astronomy Missions in China

Chen Zhang

represent Prof. Shuang-Nan ZhangInstitute of High Energy Physics

National Astronomical Observatory Chinese Academy of Sciences

zhangchen12@gmail.comzhangsn@ihep.ac.cn

2009-2-06 AXRO 2009, Prague 2

Space X-ray Astronomy

• Matter under extreme conditions• Formation of structure• Life cycle of matter and energy

An overview of Space astronomy Missions in China

• Still no space astronomy satellite launched up to now • Focusing on high energy astrophysics and solar physics,

developing the space optics, radio,  gravitational wave and dark matter detection.

• Strengthen international cooperation• Recent scientific programs

– “Black Hole Probe” (BHP): HXMT, SVOM, Polar– “Diagnostics of Astro-Oscillations” (DAO): XTP,…

– “Portraits of Astrophysical Objects” (PAO), dark matter detection, solar microscope, solar portraits

2009-2-06 AXRO 2009, Prague 3

Prof. S.N. Zhang is the coordinator of BHP, DAO and PAO programs.

2009-2-06 AXRO 2009, Prague

The Hard X-ray Modulation Telescope: planned for launch around 2010-2011

Ready for Phase C/D:

2007: official announcement of selection as China’s first dedicated astronomy;

2008: completion of phase A.

Full funding decision not made yet!

4

Based on the direct demodulation (DD) method

2009-2-06 AXRO 2009, Prague

Broad band (1-250 keV) and large collection area (5000 cm2@100 keV) •Hard X-ray full sky survey

•A high precision hard X-ray sky map•About 1000 new hard X-ray sources•Diffuse background and cosmic variance•Discover highly obscured supermassive BHs

•Pointed observations of high energy sources•Dynamics and radiation near compact objects: X-ray binaries, AGNs, SGRs•Clusters of galaxies, GRBs, SNRs

Main science of HXMT

5

2009-2-06 AXRO 2009, Prague

HXMT full sky survey

•1 year exposure map1 year exposure map

6

•Power spectrum•Light

curve

HXMT Pointed Observation

2009-2-06 AXRO 2009, Prague 7

2009-2-06 AXRO 2009, Prague

Low Energy X-ray Instrument (LE)

(1-15 keV)SCD, 384 cm2

Medium Energy X-rayInstrument (ME)

(5-30 keV)SiPIN, 952 cm2

Detectors onboard

High Energy X-ray Instrument (HE)

(20-250 keV)NaI(Ti)/CsI(Na) crystal

18 modules, 5000 cm2

8

2009-2-06 AXRO 2009, Prague

Detectors LE: SCD, 384 cm2;ME : Si-PIN, 952 cm2

HE : NaI/CsI, 5000 cm2

Energy Range LE: 1-15 keV;ME: 5-30 keV;HE: 20-250 keV

Time Resolution HE: 25μs; ME: 20μs;LE: 1ms

Energy Resolution LE: 8% @ 6 keV (goal: 2.2%)ME: 15% @ 20 keV (goal: 5%)HE: 19% @ 60 keV (goal: 17%)

Field of View of one module

5.7°×1.1°; 5.7°×2.2°

Angular Resolution < 5' (20σ source)

Source Location <1' (20σ source)

Sensitivity (3σ, in 105s) LE: 4.4×10-5 cts cm-2s-1 keV–1 (@6keV)ME: 2.6×10-5 cts cm-2s-1 keV–1 (@20keV)HE: 3×10-7 cts cm-2s-1 keV–1 (@100keV)

Orbit Altitude: ~550 km ; Inclination: ~43°

Payload Mass ~1000 kg

Nominal Lifetime 4 years

9

2009-2-06 AXRO 2009, Prague 10

20-250

2009-2-06 AXRO 2009, Prague

China-France joint GRB mission: SVOM

• Main Science– GRBs: Diversity and unity, Radiation

processes, Early afterglow, GRB-supernova connection, Short GRB progenitors

– Cosmology and Fundamental Physics : Star formation, Host galaxies, Cosmological parameters, Probing Lorentz invariance…

11

2009-2-06 AXRO 2009, Prague

China-France joint GRB mission: SVOM

12

ECLAIRs: Hard X-ray Imager 4-150 keV

VT: 45 cm Visible Telescope

Service platformService platform

Star sensor

GRM: Gamma-Ray Monitor 30-5000 keV (IHEP)

XIAO: Soft X-ray Telescope

0.5-2 keV

Status•phase A has ended•phase B to start soon

• reviews completed from both sides

•China & France funding approved•Planned launch in 2013-2014

2009-2-06 AXRO 2009, Prague 13

Instrument Band, (keV)GRB/yr, at z > 6

IBIS, INTEGRAL

20-200 0.1-0.5

BAT, Swift 15-150 1.3-4.0

ECLAIRs, SVOM

4-50 2.0-4.0

China-France joint GRB mission: SVOM

Goals (beyond Swift)•Higher redshift GRBs (with ECLAIRs)•Deeper and more uniform sampling of optical afterglows (with XIAO & VT)•Better E_peak measurements (with GRM)

GRB prompt emission polarization: one of the last observables of GRBs•Different GRB models

– E-M Model: well defined, moderate Plin ~ 50%

– Fireball Model: high values excluded Plin ~ 10-20 %

– Cannon ball Model: full range possible Plin = 0 - 100%

•Probe quantum gravity (???): – Amelino-Camelia G., 2000, Nature,

408, 661– Piran T, 2005, Lect. Notes Phys,

669, 351– Fan, Y-Z; Wei, D-M; Xu, D. 2007,

MNRAS, 376, 1857

2009-2-06 AXRO 2009, Prague 14

See papers discussing various GRB models: T. Piran, A. Dar, M. Lyutikov, D. Eichler, G. Ghisellini, D. Lazzatti, M. Medvedev, E. Rossi etc.

From M. Lyutikov, 2003

14

Gamma-ray burst polarization experiment onboard China’s Spacelab: POLAR

Gamma-ray burst polarization experiment onboard China’s Spacelab: POLAR

• Onboard China’s spacelab TG-2: launch time 2011-12

• A China-led international collaboration (Switzerland, France, Poland)

• FOV of POLAR: ~½ sky

2009-2-06 AXRO 2009, Prague

Tian-Gong Tian-Gong 天宫天宫Palace in HeavenPalace in Heaven

•Plastic scintillator stacks

15

Instrument concept proposed by N. Produit, et al., NIM (2005)

POLAR capability summary

0 10 20 30 40 50 60 70 80 90 1000

20

40

60

80

100

120

140

160

180

Minimum Detectable Polarization with 3σ (%)

Num

ber

of

GR

Bs (

N <

MD

P)

One year observation of POLAR

TS2/DM2 FOV = 2π

0 10 20 30 40 50 60 70 80 90 1000

20

40

60

80

100

120

140

160

180

Minimum Detectable Polarization with 3σ (%)

Num

ber

of

GR

Bs (

N <

MD

P)

One year observation of POLAR

TS2/DM2 FOV = 2π

•1010 GRBs per year down to GRBs per year down to 8%8%, or , or •6060 GRBs per year down to GRBs per year down to 30%30%, or , or 100100

GRBs per year down to GRBs per year down to 50%50%

polarizationpolarization, if , if allall POLAR GRBs are POLAR GRBs are

localized independently to ~degrees localized independently to ~degrees

accuracy by other GRB instruments.accuracy by other GRB instruments.

2009-2-06 AXRO 2009, Prague 16

X-ray Timing and Polarization (XTP) mission

2009-2-06 AXRO 2009, Prague

• Science

• Precise Light curve: Matter under extreme conditions, Neutron Star state equation, BH basic parameters formation and growth …

• Polarization of X-ray: Radiation mechanism…• Diffuse X-ray emission, Gas distribution in Galaxy• …

• Goal

• The most sensitive light curve and polarization observation at 1-30 keV

• Effective area• Low energy end, MCP @0.5-2 keV, the same about IXO• High energy end, Multilayer @30 keV, ~ 10 times of IXO

17

X-ray Timing and Polarization (XTP) mission

2009-2-06 AXRO 2009, Prague

1. Using a large array of small telescopes to achieve a very large collection area competitive w.r.t. IXO for temporal and spectral studies of X-ray binaries and bright AGNs.

2. Sacrifice angular resolution (~1’) in exchange for large collection area technically easier

18

Hard X-ray polarization telescope

Soft X-ray telescope

Soft X-ray polarization telescope

All-sky monitor

Hard X-ray telescope

2009-11-19 Shuang-Nan Zhang @ University of Ferrara, Italy 19

HERO concept: High Energy Replicated Optics – Small Aperture, Short Focal Length and Shallow Grazing Incidence

Using a small mirror array to achieve a large collection area: technically more feasible than single large mirror.

Ramsey et al, SPIE 2000

• Full-shell shallow-graze-angle iridium-coated replicated mirrors

• Complex coating procedures avoided

• Requirements for mirror surface quality relaxed

2009-11-19 Shuang-Nan Zhang @ University of Ferrara, Italy 20

MCP X-ray Optics

Pore glass coated with Iridium: extremely light weight, compact and robust (Fraser et al 2009)

XTP timeline and funding

• 2010 R&D (Phase 0, A)– CAST and IHEP XTP platform: € 50 K

– IHEP detector: € 180 K

– CAS XTP Phase 0, A: € 500 K

– NSFC detector and mirror: € 320 K

– NAOC X-ray lab: € 400 K (applied)

• 2012-13: Phase B

• 2018 launch: before IXO

2009-2-06 AXRO 2009, Prague 21

Summarization

• “Black Hole Probe” program– HXMT: hard X-ray observation, around 2010-2011– SVOM: GRB, 2013-2014– Polar: GRB polarization, 2011-2012

• “Diagnostics of Astro-Oscillations” program– XTP: Light curve and polarization, Phase A

• “Portraits of Astrophysical Objects”, dark matter detection, solar microscope, solar portrait

2009-2-06 AXRO 2009, Prague 22