discovery and evolution of a new galactic black hole candidate xte j1752-223 discovery and evolution...

Discovery and Evolution of aNew Galactic Black Hole Candidate

XTE J1752-223

N. Shaposhnikov1,2,3, J. Swank3, C. Markwardt1,2,3, H. Krimm2,3,4

The Astrophysical Journal, 723, 2,1817 1University of Maryland, Astronomy Department2Center for Research and Exploration in Space Science & Technology (CRESST)3NASA/Goddrd Space Flight Center4Universities Space Research Association

4th MAXI Workshop 2010, Tokyo, November 29, 2010

Discovery

XTE J1752-223

• RXTE/PCA Galactic Bulge Scans showed an unidentified new source on October 21, 2009. Scans on October 23 fully confirmed a new source (Atel #2258)

• Subsequent Swift/XRT observation showed bright point source with very hard non-thermal spectrum with index Γ = 1.2 and NH =0.47×1022 cm-2 (Atel #2261)

October, 21 2009

October 20, 2009

October, 23 2009

Discovery and Evolution of a New Galactic Black Hole Candidate XTE J1752-223

4th MAXI Workshop 2010, Tokyo, November 29, 2010Shaposhnikov, Swank, Markwardt &Krimm

XTE J1752-223 Evolution

4th MAXI Workshop 2010, Tokyo, November 29, 2010

Discovery and Evolution of a New Galactic Black Hole Candidate XTE J1752-223

Shaposhnikov, Swank, Markwardt &Krimm

Hardness – Intensity Diagram

Data modeling:Energy spectral model• Comptonization (BMC)• Gaussian for the iron line

at ~6.5 keV• Modified by interstellar

absorption (measured by Swift/XRT)

• High energy cutoff

Power Density Spectra• Power law or broken

power law for the broad band variability

• Loretzians for QPOs

RXTE Data Spectral Analysis

4th MAXI Workshop 2010, Tokyo, November 29, 2010

Discovery and Evolution of a New Galactic Black Hole Candidate XTE J1752-223

Shaposhnikov, Swank, Markwardt &Krimm

QPO

Shaposhnikov et al. ApJ,2010

XTE J1752-223 Variability Evolution

4th MAXI Workshop 2010, Tokyo, November 29, 2010

Discovery and Evolution of a New Galactic Black Hole Candidate XTE J1752-223

Shaposhnikov, Swank, Markwardt &Krimm

LHS HIMS SIMS HSS IS LHS

Low Hard State in XTE J1752-223

4th MAXI Workshop 2010, Tokyo, November 29, 2010

Discovery and Evolution of a New Galactic Black Hole Candidate XTE J1752-223

Shaposhnikov, Swank, Markwardt &Krimm

XTE J1752-223

GX 339-4

Power Spectra

Fourier Resolved Spectroscopy (FRS)

4th MAXI Workshop 2010, Tokyo, November 29, 2010

Discovery and Evolution of a New Galactic Black Hole Candidate XTE J1752-223

Shaposhnikov, Swank, Markwardt &Krimm

XTE J1752-223

Low Hard State

GX 339-4

Fourier Resolved Spectroscopy (continued)

4th MAXI Workshop 2010, Tokyo, November 29, 2010

Discovery and Evolution of a New Galactic Black Hole Candidate XTE J1752-223

Shaposhnikov, Swank, Markwardt &Krimm

State Transition

HIMS SIMS

Lowest QPOs during the beginning of the transition are softer than the time averaged spectrum. As the transition evolves they quickly become harder (Sobolewska & Zycki 2006). QPO spectrum is always harder that

the broad band noise.

Fourier Resolved Spectroscopy (HIMS)

4th MAXI Workshop 2010, Tokyo, November 29, 2010

Discovery and Evolution of a New Galactic Black Hole Candidate XTE J1752-223

Shaposhnikov, Swank, Markwardt &Krimm

FRS normalized by total spectrum

FRS normalized by the non-thermal

spectral component

(Shaposhnikov et al. 2010)

Disk black body spectral component is stable!RMS ratio normalized on the power law component alone is decreasing

from the level of 50% (LHS!).

What can we learn from spectral data?Nature of the power law

E- Thermal Comptonization:

€

Nsc ~ τ 2,

€

η =4kT /mec2

€

α ~ [(4kT /mec2)2τ 2]−1

(Rubicki & Lightman, 79)

Bulk Motion Comptonization:

(S & Titarchuk, 2009)

4th MAXI Workshop 2010, Tokyo, November 29, 2010

Discovery and Evolution of a New Galactic Black Hole Candidate XTE J1752-223

Shaposhnikov, Swank, Markwardt &Krimm

(Laurent & Titarchuk 2010)

€

η∝τ −1, Nsc ∝ τ ⇒ α ≈ const

Thermal versus Bulk motion Comptonization

4th MAXI Workshop 2010, Tokyo, November 29, 2010

Discovery and Evolution of a New Galactic Black Hole Candidate XTE J1752-223

Shaposhnikov, Swank, Markwardt &Krimm

(S & Titarchuk 2010)

XTE J1550-564

Thermal

BMC

High Energy Cutoff Evolution

Thermal

BMC

XTE J1550-564 (1998 ouburst) Index vs Luminosity

On the behavior of RMS spectrum

4th MAXI Workshop 2010, Tokyo, November 29, 2010

Discovery and Evolution of a New Galactic Black Hole Candidate XTE J1752-223

Shaposhnikov, Swank, Markwardt &Krimm €

F(v) = (1− fC )B(v) + fC ⋅ B(v')0

∞

∫ C(v ',v)dv'

LHS HIMS

€

C = Cthermal

€

C = Cthermal + CBMC

Thermal Comtonization is variable, BM Comptonization is not!

Correlation scaling: BH mass estimate

4th MAXI Workshop 2010, Tokyo, November 29, 2010

Discovery and Evolution of a New Galactic Black Hole Candidate XTE J1752-223

Shaposhnikov, Swank, Markwardt &Krimm

Scaling Laws GX 339-4 vs XTE J1752-223 GRO J1655-40 vs XTE J1752-223

sv = 0.88 sn=0.41GX 339-4:

M=12.5 M ,d=5.7 kpc (S & Titarchuk 2009)

M1752≅11M d≅3.5 kpc

S & Titarchuk 2009, ApJ

sv = 1.5 sn=0.96GRO J1655-40:

M=12.5 M, d=5.7 kpc (Hjellming & Rupen 1995)

M1752≅9.5M d≅3.8 kpc

MAXI J1659-152

4th MAXI Workshop 2010, Tokyo, November 29, 2010

Discovery and Evolution of a New Galactic Black Hole Candidate XTE J1752-223

Shaposhnikov, Swank, Markwardt &Krimm

Evolution Index – QPO Frequency during the rise episode

sv = 1.62 +/- 0.04GX 339-4:

M=12.5 M ,d=5.7 kpc (S & Titarchuk 2009)

M1659≅20+/-3 M

Hardness-Intensity Diagram

SUMMARY • On October 21 RXTE discovered a new X-ray transient source

XTE J1752-223• Spectral and variability properties and the evolutionary

pattern are consistent with other Galactic BH candidates• XTE J1752-223 exhibited a uniquely stable prolonged low-

hard state• RXTE data allows spectral, timing analysis and Fourier

resolved spectroscopy revealing a new phenomenology. This helps to identify sources of different types of variability (noise, QPOs). QPO seems to be produced in the Compton Corona.

• Bulk Motion Comptonization in the converging flow provides a very promising framework for explaining different observational aspects of accreting BHs

• We estimated BH masses in XTE J1752-223 and MAXI J1659-152 of about 10 and 20 solar masses correspondingly

• The presented results are entirely due to unique RXTE capabilities, large collection area, high time and moderate spectral resolution and unmatched monitoring capabilities.

Discovery and Evolution of a New Galactic Black Hole Candidate XTE J1752-223

4th MAXI Workshop 2010, Tokyo, November 29, 2010Shaposhnikov, Swank, Markwardt &Krimm