Accretion Phenomena in Accreting Neutron Stars From atol to Z-sources Norbert S. Schulz, L. Ji, M. Nowak Claude R. Canizares MIT Kavli Institute for Astrophysics

Accretion Phenomena in Accreting Neutron Stars From atol to Z-sources

Norbert S. Schulz, L. Ji, M. Nowak Claude R. CanizaresMIT Kavli Institute for Astrophysics & Space Research

Chandra Accretion Workschop— Cambridge, MA. July 13-15, 2010

Accretion Disk Processes with Chandra HETG

T. Kallman GSFC, Greenbelt MD

Atoll-, Banana- and Z-sourcesSchulz, Hasinger&Truemper 1989, Hasinger & van der Klis 1989


Atoll-, Banana- and Z-sources

Schulz, Hasinger&Truemper 1989


sub-LEddington

accretion rates

super-LEddington

accretion rates

Spectral States of XTE J1701 - 462: Link Between Z and Atoll Sources (Lin et al. 2010)

Atoll-sources with Chandra HETG


1S 0921-63 74.7ks 14U 0614+091 200.2 ks 44U 0919-54 28.5 ks 14U 1254-690 51.6 ks 14U 1323-619 39.2 ks 14U 1543-62 37,8 ks 14U 1608-52 23,8 ks 14U 1624-49 73.7 ks 14U 1630-47 51.1 ks 14U 1636-53 110.1 ks 44U 1705-44 59.2 ks 34U 1728-34 135.3 ks 44U 1735-44 73.7 ks 34U 1746-37 41.7 ks 14U 1812-12 86.1 ks 14U 1820-39 120.0 ks 5

4U 1822-00 2.2 ks 14U 1822-37 180.4 ks 34U 1857+01 4.9 ks 1EXO 0749-767 76.4 ks 3GS 1826-24 164.2ks 3GR 1915-11 328.4ks 11Her X-1 245.0ks 104U 1730-335 28.7ks 1Ser X-1 76.8ks 1XB 1916-05 46.4ks 1

26 Atoll sources for2.3 Msec in 69 observations

M. Linares PhD Thesis 2009

Accretion of Matter in X-ray Binaries

~7 8 9 10 11 log r [cm]

Photo-emission and absorptionline spectra for log Lx > 37 [erg/s]

Spectralcontinua


Accretion Disk Morphologies

Fe

XX

VI


OpticaLthick cool reflectionsurface

Thin & hot ionization layer

Accretion disk atmosphere

Accretion disk atmosphere/Accretion Disk Corona *ADC)

Accretion Disk Atmospheres

Assumptions:

- energy balance between heating by incident radiation and cooling by recombining emission. - uniform static corona in thermal equi- librium.

Compare:

- the deduced emission measure n2V from the measured line luminosity Lline=n2VaatomElineAion with the expected one from an X-ray heated ADC d EM/d = 2.5x1065-3L38

2 f(R,T)

yellow:measured quantities blue atomic data and ADC models green: quantities to compare

log Lx = 38 = 37


Accretion Disk Coronae

4U 1626-67 (Schulz et al. 2002)

Her X-1 (Ji et al. 2008)

2S 0921-80 (Kallman et al. 2003) Cir X-1 (Schulz et al. 2008)


Atoll Sources: 4U 1822-37 with Einstein

Fe

XX

VI


White & Holt 1982

Atoll Sources: 4U 1822-37 with RXTE

Fe

XX

VI


Heinz & Nowak 2001White & Holt 1982

Atoll Sources: 4U 1822-37 with Chandra

Fe

XX

VI


Cottam et al. 2001


Fe

XX

VI


Ji et al. 2010


Fe

XX

VI


Heinz & Nowak 2001


Fe

XX

VI



Fe

XX

VI


Atoll Sources: 4U 0614+091 with Chandra

Fe

XX

VI



Fe

XX

VI


Schulz 1999, Piraino et al. 1999, Migliari et al. 2010, Schulz et al. 2010


Fe

XX

VI


Madej et al. 2010Schulz et al. 2010


Fe

XX

VI


Banana-sources with Chandra HETG


GX 3+1 9.2 ks 1GX 13+1 29.9 ks 1GX 9+9 46.2 ks 1

GX 13+1 150 ks 5GX 9+9 200 ks 3

3 Banana sources for85.3 ksec in 4 observations

Banana Sources: GX 13+1 with Chandra

Fe

XX

VI


GX 13+1 (4U 1811-17) is a persistently bright(Fx = 9x10-9 erg cm-2 s-1, NH

= 1022 cm-2) LMXBwith a K5 III companion at distance of 7+/-1 kpc.

Z-sources with Chandra HETG


Cir X-1 265.4 ks 9Cyg X-2 258.0 ks 5GX 17+2 79.9 ks 3GX 340+0 80.1 ks 4GX 349+2 51.1 ks 4GX 5-1 81.8 ks 5Sco X-1 15.0 ks 1

GX 349+2 130.0 ks 4

7 Z -sources for831.8 ksec in 31 observations

7th Microquasar Workshop, Foca, Sept. 1-6, 2008

Z-source and Microquasar: Cir X-1

QuickTime™ and aGIF decompressor

are needed to see this picture.

Possibly ultra-relativistic jet

Neutron star binary

Low/Intermediate mass companion

Accretion disk wind of 400 -2000 km/s

Variable cool & hot absorbers

Suggested soft ionized absorber

(Parkingson et al. 2003)

Fender et al. 2004

Z-sources with Chandra HETG


Cyg X-2 like Z-tracks

Sco X-1 like Z-tracks

Church&Church 2001, 2004Church et al. 2006, 2010Jackson et L. 2009

Extended ADC model

Interpretation of Z-tracks with ExADCs

Fe

XX

VI


Church, Jackson,& Church 2009

Z-sources: Cyg X-2

Low-mass X-ray Binary: Z-source prototype Distance: 8-12 kpc Luminosity: >> 1037 erg/s Companion: A9III evolved, 0.6 MSun

Binary period: 9.84 days Compact Object: Neutron star(type I bursts)

Spectral Properties (DiSalvo et al. 2002):

Column Density: 2x1021 cm-2

Diskbb/bbody : 0.8 keV / 1.7 keV Electron Temperature: > 3 keV Comptoniztation (seed): 1-2 keV Fe-K line: 6.7 keV, 42 eV EW


Extended ADCs in Z-sources: Cyg X-2


rdisk = [0.7 -- 2.7] x1010 cm

nZ = < 1014 cm-3

nfexxv ~ 1016 cm-3

log 2.8 (HB) --> 3.4 (FB)Lx : 0.6 LEdd --> 1.4 LEdd

Summary

Chandra HETG has observed 36 LMXBs (identified Atoll, Banana, and Z-Sources) for ~ 3.2 Msec in 104 observations.

The Atoll source 4U 1822 -37 shows a thin ionization layer of ionizationparameter log < 2.6 inferring Lx ~ 1038 erg/s;Highly ionized Fe XXVI emission from central corona

The Atoll source 4U 0614+091 is likely of ultra-compact nature withan accretion disk radius of a few 109 cm, probable higher Ne abundance.It exhibits a highly variable and moderately relativistic O VIII line fromit inner disk

The Z-source Cyg X-2 exhibits broad line emission indicating the presenceof an extended (r~1010 cm) ADC . Line fluxes indicate ADC heating from HB --> NB --> FB from sub- to super Eddington luminosities,

Documents

Accretion Phenomena in Accreting Neutron Stars From atol to Z-sources Norbert S. Schulz, L. Ji, M. Nowak Claude R. Canizares MIT Kavli Institute for Astrophysics