andrea santangelo, iaat bologna 15.05.2007simbol-x workshop “broad band continuum and cyclotron...
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Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
“Broad Band continuum and Cyclotron Scattering Features in the Spectra of
Accreting X-ray Pulsars”
Andrea Santangelo, E. Kendziorra, C. Tenzer, D. Klochkov, D. Horns, T. Schanz, M. Martin
Institut für Astronomie und AstrophysikKepler Center for Astro and Particle Physics
Karls Eberhard Universität Tübingen
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
Courtesy of Scientific American X-ray Binaries with a NS
Liu et al. A&A, 2000, 2005
G10B 12
Most of them are in HMXRB
A few LMXRB (Her X-1, 4U1626-67,
GX1+4)
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
Accretion
Kuster, 2003
Ghosh & Lamb, 1978
B ~ 1012-1013 GOn grounds of magnetic flux conservation during the SN core collapse
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
The „Transient“ Behaviour of the Be/X-ray Binaries
Kretschmar, 1996
1 Crab1mCrab
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
Accretion Columns ? Basko & Sunyaev, 1976
Kuster, 2003
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
Or Accretion “Spaghetti” ?
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
Kretschmar, 1996 after Harding, 1994
erg/sec 1037L
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
BB
Fe Lines
PL ~
Ecyc
Wien Hump
Dal Fiume et al., A&A 1998
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
POHEI (E) =E E<Ecut
E>EcutEexp(-(E-Ecut)/Ef))
)EEE
exp(1
1)E(FDCO
cut
kTE
22kTE
21 e))E(oE(e)EAEA(NPEX 21
White et al, 1983
Tanaka, 1986Mihara, 1995
Approximates thermal comptonization Sunyaev and Titarchuk, 1980
The continua ?
Segreto, 2001
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
1st Science Question• Which is the broad band continuum of accreting Pulsar ?• What are the physical processes that generates the continuum
emission in the accretion column? And the ones that reprocess the emerging radiation ?
Becker & Wolff, ApJ 2007
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
Broad Band Phase Resolved Spectroscopy with high granularity in phase
1st Requirement
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
Cyclotron lines basic theory
γmc
eBωc
Gauss 12
10 of units in B keVB6.11E 12c,e cn ωnω
The motion of the electron perpendicularly to the B field is quantized in the Landau levels
Equispaced
If relativistic corrections are taken into account z1
1
θsin
1θsinBBn2mc
mcω 2
2
crit
2
2n
θ is the angle between the photon and the magnetic field
G1014.4e
cmB 13
32
cr
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
Cyclotron lines basic theory (2)
Electron is excited to the n Landau level
Lifetime is short
De-excitation to ground state via single or multiple photon emission
Mean free path is short, quasi instantaneous re-capturing of the photon
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAATSchönerr et al., PHD Thesis, 2007
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
1:(1.9±0.05):(2.8±0.05):(3.9±0.1)
Harmonic ratios
The EW of harmonics were found to be larger than the fundamental
Shallow First
Deep Second
RXTE Heindl et al. 1999; BeppoSAX Santangelo et al., 1999
E1cyc 12.74
E2cyc 24.16
keV
E3cyc 35.74
E4cyc 49.5
keV
E5cyc 60. keV
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
2nd Science Question• What can we learn from phase resolved studies of
Cyclotron line energy, width and depth? • Can we extract Physical information (Physical
parameters of the plasma!) from the phase variation of the line shape and emission wings ?
• Excellent progress have been made in the last years!!
G. Schönherr et al., A&A, submitted
O. Nishimura, PASJ, 2006
Araya & Harding, ApJ 517, 334 (1999)
Araya & Harding, ApJ 544, 1067 (2000)
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
f(θ)
f(E) f(p)
• energy distribution ~ f(E)
• isotropic injection
• internally irradiated plasma
• electron temperature Te
• rel. Maxwellian distribution
• ground Landau state
• low-density plasma
Ingredients: geometry, photons and electrons
B~1013G
cylinderτcy = τ/sin(θ)
θ
<σ(E,θ)>f(p,Te)
QM relativistic cross sections
E┴
Courtesy of Gabi Schönherr, IAAT/Bamberg; Schönherr et al., 2005
Schönerr et al., PHD Thesis, 2007
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
Line morphologySchönerr et al., A&A submitted 2007
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
Phase Resolved Spectroscopy of harmonics parameters and capability of
morphological studies
2nd Requirement
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
The luminosity dependence
? H
MM col
? MH Anticorrelation ?
Correlation ?
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
Correlation or Anti-correlation?
Tsygankov et al., 2006 V0332+53, Outburst 2005 Anticorrelation is clearly observed
Staubert et al., 2007 Her X-1, 5 years of data Correlation is clearly observed
Caballero et al., 2007 A0535+26
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
Again X0115+63
Tsygankov et al., 2007, astro-ph 0704.2874v1 4U 0115+63, Outburst 1999, but also 2004
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
3rd Science Question
• What can we learn from the luminosity dependence of Cyclotron line energy, width and depth ?
• Correlation/Anticorrelation are related to the accretion luminosity ? Do we observe a change of regime around 1037 ergs/sec ?
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
Capability of monitoring with good accuracy and wide dynamic range the
luminosity dependence of CRSF parameters
3rd Requirement
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
Simbol X: broad band
seck1
)08.0(04.067.0Depth
)0.3(3.04.7
)2.1(6.05.38E0
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
Simbol X: Phase Resolved Spectroscopy
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
Simbol X: Morphology
seck3
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
Luminosity dependence, V0332
%2Depth
%1
%1E0
%3Depth
%8
%1E0
Bologna 15.05.2007 Simbol-X Workshop Andrea Santangelo,IAAT
Conclusions• Simbol X will be able to observe with unprecedented accuracy
– Broad band phase resolved continuum (BB, PL, Cut-off, harder tails)
– The Phase Dependence of CRSF – The Luminosity dependence of CRSF parameters– Phase Resolved Line shapes studies
Emission processes of spectral formation …spectral reprocessing
Geometry of the pulsed components …of the line forming region
Plasma Parameters …B, T, tau, etc…