Timing studies of the soft emission in the low-hard state of black hole X-ray binaries with XMM-Newton

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1 Timing studies st emission in low-hard state black hole X-ray binaries with XMM-Newton Holger Stiele Albert K. H. Kong (NTHU) National Tsing Hua University, Hsinchu The X-ray Universe 017, Roma 7. June 017

mass companion star (M s 1 M, type A,F,G,K,M) through a

2 Low mass black hole X-ray binary Central object is a stellar mass (3-0 M ) black hole Accretes matter its low mass companion star (M s 1 M, type A,F,G,K,M) through a disc (Rochelobe overflow) X-ray emitting region close to event horizon R S

State art Timing properties BH XRBs as seen with Power Density [(rms/) /Hz] 0.1 0.

power law noise Gilfanov 010, X-ray emission BH binaries RXTE (3-0 kev) hardness -

004, A&A, 46, 587 Frequency (Hz) Power Density [(rms/) /Hz] 0.1 0.01 10-3 10-4 10-5 10-6 0.

3 State art Timing properties BH XRBs as seen with Power Density [(rms/) /Hz] XTE J Frequency (Hz) U McClintock & Remillard 006 Black Hole binaries power law noise Gilfanov 010, X-ray emission BH binaries RXTE (3-0 kev) hardness - intensity diagram HIMS HSS SIMS LHS Power Tomaso Belloni Casella et al. 004, A&A, 46, 587 Frequency (Hz) Power Density [(rms/) /Hz] XTE J GRO J GRS Frequency (Hz) 100 band limited noise and QPO McClintock & Remillard 006 Black Hole binaries

= 1.5+0.01 0.09 = Parameter 339/04 339/09 Sw1753/06 a 339/04 Parameter 339/09 Sw1753/06 Sw1753/1/1 Sw1753/1/ H 1743 For October 01 observation Swift J1753.

4 = = Parameter 339/04 339/09 Sw1753/06 a 339/04 Parameter 339/09 Sw1753/06 Sw1753/1/1 Sw1753/1/ H 1743 For October 01 observation Swift J , index f Covariance to T Do and not Parameter 339/09 Sw1753/06 Sw1753/1/1 Sw1753/1/ Hwith 1743 in339/04 Covariance to values agrees bars (s)o Covariance to a October, (s) is Notes: (s), : short-, long-timescale For 01 observation Swift J , index a 3676 Covariance and W. Yu (l (s) (s) to should be read like this: for 004 observation 339 4, indices obtain values and agrees bars with a 3676 Tin and (s) W. Yu (s) (s) Bigger are smaller than one Tin, (s) Notes: (s), :parameters short-, long-timescale Table temperature comparing on both timescales Tin 5. Behaviour index and inner disc (s) for obta Bigger 339 4, indices should be read like this: 004 observation to those. Table 5. Behaviour (s) index and inner disc temperature comparing parameters obtain Short-term to long-term and Tin parameters Short-term to long-term are smaller than one and parameters to those Short-term tobb long-term T Do not Sw1753/1/ Parameter 339/04 339/09 Sw1753/06 Sw1753/1/1 H 1743 in not agree Short-term to long-term Tin Do not Do Parameter 339/04 339/09 Sw1753/06 a Tin Do not observation Swift J , Do not agreeindex For fr a For October October observation Swift J , index Covariance to Ta in Do not values and agrees bars with a lies index spectrum values to and(s)agrees barsbetween with Covariance For October 01 observation Swift J , (s) o a (s), : short-, long-timescale, and agreesnotes: bars with one spectrum long-scale Forvalues October 01 observation Swift J , lies between Notes: (s), :index short-, long-timescale, (s)is Bigger 339 4, should be read like this: for 004 observation indices obta (s), : short-, long-timescale, isone short for agree bars. The table should be read like this: for , indices obtain values Notes: and agrees bars with observation long-scale Tin N (s) one are smaller than long-timescale should read like 004 observation 339 4, longand short-term are smaller than indices one Xbe Notes: (s),this: : for short-,, is short for agree bars. The table T (s) in be areread smaller should like than this: for one 004 observation 339 4, indices long- and short-term Short-term to long-term i i are smaller than one Short-term to long-term i=1 Do not agree Tin Do not Tin Do not a For October 01 observation Swift J , index spectrum lies between a For October 01 observation Swift J , index f and values agrees bars with one long-scale values agrees bars with o cov Notes: (s), : short-, long-timescale, is short forand agree bars. The table q Notes: (s), : short-, long-timescale, cov,norm should be read like this:for 004 observation 339 4, indices long- and short-term is should be read like this: for 004 observation 339 4, indices obtain are smaller thanxs,y one are smaller than one Covariance ratios RBB = km R = 1.1 Covariance spectrum: rms spectrum between a narrow band (X) and a broad reference RBB =band km R = km BB 3.9 (Y; 1 4 kev; Wilkinson & Uttley 009, X MNRAS X 397, Y cov = N 1 666),, cov = 1 N N X 1 i=1 Xi X cov q xs,y Yi Y km Y = Error bars are = smaller compared to normal cov,norm rms spectrum p = + ratio:max model independent way max = + Ratio cov. on long (segments < max,1 kev max,4 70s with.7s time bins) and short time max,1 < max,4 scales kev (segments 4s with 0.1s time bins) 8 kev Increase ratio at lower energies has been interpreted as sign additional disc variability on long time scales (Wilkinson & Uttley 009, MNRAS 397, 666) 8 kev Figure 9. Covariance ratio all eight observations. The ratios are by dividing on shorter timescales. MNRAS 45, (015) Figure 9. Covariance ratio all eight observations. The ratios are by dividing on shorter timescales. Figure 9. Covariance ratio all eight observations. The ratios are by dividing covarian on shorter timescales. MNRAS 45, (015) Stiele & Yu 015, MNRAS 45, 3666 Covariance to p variability on different time scales compare Figure 9. Covariance ratio all eight observations. The ratios are by dividing on shorter timescales. MNRAS Figure 9. 45, Covariance ratio (015) all eight observations. The ratios are by dividing covarian

Some remain hard Some outbursts do not make it to st state Stiele & Yu 016, MNRAS, 460, 1946, A.

010, MNRAS 408, 1796 Figure. Hardness intensity diagram RXTE/PCA data for complete 009 outburst (blue line) and 008 outburst (red line).

Different symbols indicate different timing properties: type-a QPOs (diamonds), type-b QPOs (squares), type-c QPOs (filled triangles), strong band-limited noise components in PDS (stars), weak

Downloaded http://mnras.oxfordjournals.org/ at National Tsing Hua H 1743 3 QPO has been detected showed are marked by (green) a triangles, so-called and (red) star indicates first observation.

5 Some remain hard Some outbursts do not make it to st state Stiele & Yu 016, MNRAS, 460, 1946, A. Kong Stiele & Kong 016, MNRAS, 459, 4038 GS H Swift/XRT PCU COUNTS/S 10 H , RXTE/PCA Outburst evolution H HARDNESS RATIO Motta et al. 010, MNRAS 408, 1796 Figure. Hardness intensity diagram RXTE/PCA data for complete 009 outburst (blue line) and 008 outburst (red line). The two paths start upper right corner and proceed in a counter-clockwise direction. Different symbols indicate different timing properties: type-a QPOs (diamonds), type-b QPOs (squares), type-c QPOs (filled triangles), strong band-limited noise components in PDS (stars), weak band-limited noise components in PDS (empty triangles), weak power-law noise in PDS (crosses). The solid line marks transition HIMS to SIMS and dot dashed line separates SIMS HSS. Downloaded at National Tsing Hua H QPO has been detected showed are marked by (green) a triangles, so-called and (red) star indicates first observation. failed outburst in 008 and 014 zero-centered Lorentzians for band-limited noise (BLN) compo- XMM-Newton nents, and Lorentzians observed for quasi-periodic oscillations H (QPOs) during. XMM-Newton se two failed outbursts An XMM-Newton ToO observation GS was taken on August 6th 015 (Obs. id.: ) with EPIC/pn camera in timing mode. The exposure was 11.1 ks. We filtered and ex- GS tracted pn event showed file, using standard a SAS hard-state (version ) tools, paying particular attention to extract list s not randomized in time. only outburst in After015 using SAS task epatplot to investigate Figure 1. Hardness-intensity diagram, derived using Swift/XRT count rates. Each data point represents one observation. Observations in which a type-c wher observation is a ected by pile-up, we selected source s two stripes (306RAWX635 and 396RAWX644) centred on column with highest count rate to minimize Figure Each da QPO ha date 10th 0 remain into th outbur GS et al. 005), (Del S GRO J 004). W tra in t omitte which groupe

015 outburst GS 1354 64 Stiele & Kong 016, MNRAS, 459, 4038 Table 1. Parameters PDS Parameter 1 kev 10 kev rms BLN [%] 14.3 +0.8 0.9 16.5 ± 0.7 BLN [Hz].85 +0.85 3.0 0.66 +0.58 0.5 QPO [Hz] 0.191 ± 0.

. +1.0 1.1 PN [Hz] 0.074 +0.007 0.006 0.08 +0.006 0.005 PN [Hz] 0.084 +0.017 0.013 0.077 +0.013 0.010 rms PN [%] 15.5 +1. 0.9 17.5 +1. 0.9 tion (variable versus constant), indices is same in both cases.

6 015 outburst GS Stiele & Kong 016, MNRAS, 459, 4038 Table 1. Parameters PDS Parameter 1 kev 10 kev rms BLN [%] ± 0.7 BLN [Hz] QPO [Hz] ± QPO [Hz] 0.0 ± ± rms QPO [%] ± 0.8 PN1 [Hz] ± 0.0 PN1 [Hz] ± 0.03 rms PN1 [%] PN [Hz] PN [Hz] rms PN [%] tion (variable versus constant), indices is same in both cases. From l fits RXTE GS a index abo (Revnivtsev et al. 000). The hard source remained in hard state d l parameters we Swift/XRT count rate into an RXTE Comparing count rate to on (001) for 1997 outburst, we brightness was reached in both out )absorbed flux during 015 out fits is shown in Fig. 3. c 016 RAS, MNRAS 000, 1 11 tion (variable versus constant), range observed indices is same in both cases. From l fits RXTE data 1997 outburst GS a index about 1.4 to 1.5 has been (Revnivtsev et al. 000). The hard index indicates that source remained in hard state during entire outburst. Using l parameters we converted timing stware running highest under IDL. observed Swift/XRT count rate into an RXTE/PCA count rate using PIMMS. Comparing count rate to ones presented FOR THEin 007 Brocksopp OUTBURST et al. (001) isfor a low-mass 1997 X-ray binary outburst, harbouring a we >6M found that a similar maximum brightness was reached in both outbursts. The evolution (un- 680 T. Muñoz-Darias, S. Motta and T. M. Belloni observations, are used for a more complete description different states and transitions. In this paper, we present a new tool, rms intensity diagram (RID), which allows one to map BHT states by looking only at evolution count rate and rms (i.e. without l information). As a first step we have studied case BHT 339 4, in which detailed observing campaigns have been performed during multiple outbursts observed with Rossi X-ray Timing Explorer (RXTE). accreting black hole (Hynes et al. 003; Muñoz-Darias, Casares & Martínez-Pais 008). Since its discovery (Markert et al. 1973), system has undergone several outbursts, becoming one most-studied X-ray transient. The intense monitoring carried out by RXTE during 00, 004 and 007 outbursts has yielded detailed information on evolution black hole states along outbursts (see e.g. B05). Here, we use this rich data set to study evolution flux and variability along outbursts. )absorbed flux during 015 outburst l fits is shown in Fig. 3. OBSERVATIONS We have used all RXTE public archival observations (06), 004 Timing (95) and 007 properties (39) outbursts For analysis, we have considered only data Proportional Counter Array (PCA). Goodxenon, event and single-bit data modes are used for variability. Count rates have been computed using PCA Standard mode data corresponding to PCU unit #. The analysis has been performed using HEASOFT v6.7 and a custom 3 THE RMS INTENSITY DIAGRAM The RID for 007 outburst is presented in Fig. 1 as filled dots. For each observation, net count rate corresponds to PCA channels 0 35 ( 15 kev). Only entire RXTE observations are initially considered, i.e. every dot corresponds to one observation. PDS for each observation have been also computed using procedure outlined in Belloni et al. (006). We have used stretches 16 s long and same selection as for count rate. The total power was computed frequency band Hz and fractional rmswas calculated followingbelloni & Hasinger (1990). The absolute rms displayed in diagram (Fig. 1) is by multiplying fractional rms by net count rate (PCU #) for each observation. The black solid line joins observations contiguous in time starting observation marked with a cross (i.e. observation #1). We find that source describes a continuous hysteresis pattern in anticlockwise direction. Four different regions can be distinguished in this diagram. In general PDS show a BLN component. For observations taken during outburst rise a peaked noise component with a characteristic frequency ( max = p +, where is centroid frequency, and is half width at half maximum Belloni et al. 00) in range Hz is present. The overall evolution characteristic frequency this feature is an increase with ongoing outburst. During entire outburst observed fractional rms was higher than 10 per cent, which confirms that source stayed in hard state, as transition to st intermediate state happens at fractional rms below 10 per cent (Muñoz-Darias et al. 011). For observations taken on day 54, 55, 56, 58, 60, 63, and 78 outburst a type-c QPO (Wijnands et al. 1999; Casella et al. 005) is present (parameters can be found in Table 4). All se observations are taken after outburst reached its maximum (Fig. ). The characteristic frequency QPO is in range Hz, and highest frequency is observed in observation that shows first peak in light curve after outburst maximum. The Q values (Q = /( )) se QPOs are > 4.5. For observations taken on day 55 and 58 an upper harmonic (day 55: Q uh =5.4, c;uh = 0.4 ± 0.0; c;qpo = 0.18 ± 0.01; day 58: Q uh >47.5, c;uh = ; c;qpo = ) is present, while observation taken on day 63 shows a lower harmonic (Q lh =5., c;lh = ; c;qpo = ± 0.007). Muñoz-Darias et al. 011, MNRAS 410, 679 Figure 1. rms intensity diagram for 00, 004 and 007 outbursts The dotted lines represent 1, 5, 10, 0, 30 and 40 per cent fractional rms levels. The grey area marks part diagram where solely type-b QPOs (Casella et al. 004) are seen. The dashed line joins two consecutive observations separated by 33 d due to observability constraints. The cross corresponds to first observation 007 outburst. C 010 The Authors. Journal compilation C 010 RAS, MNRAS 410, Downloaded at National Tsing Hua University Library on May, 016 Swift/XRT 3.1. Timing properties Absorbed power law In general PDS show a BLN com during outburst rise a peaked noise tic frequency ( max = p +, w and is half width at half ma range Hz is pres characteristic frequency this fea outburst. During entire outburst higher than 10 per cent, which confi hard state, as transition to so fractional rms below 10 per cent ( observations taken on day 54, 55 outburst a type-c QPO (Wijnands is present (parameters can be found tions are taken after outburst rea Revnivtsev et characteristic al. 000, ApJ, frequency 530, 955; QP Brocksopp et Hz, al. and 001, MNRAS, highest 33, frequency 517 is o shows first peak in light cur The Q values (Q = /( Photon index remains below 1.6 rms variability > 10% GS 1354 remains hard As it did in its 1997 outburst

7 Covariance ratio Stiele & Yu 016, MNRAS, 460, 1946 Figure. Power density specta in 0.8 kev (upper panel) and 8 kev (lower panel) ranges. The best fit model (red line) and four individual components (orange dashed lines) are indicated. selection has been applied here. Background have been extracted columns 3 to 5. Using standard SAS tools (rmfgen and arfgen) and latest calibration files corresponding redistribution matrix and ancillary response file have been determined. Since EPIC/pn fast-readout mode data are known to be a ected by gain shift due to Chargetransfer inefficiency (see Dı az Trigo et al. 014) and show excess emission below 1 kev (see e. g. Martocchia et al. 006), we also produced calibrated RGS (Reflection Grating Spectrometers; den Herder et al. 001) event lists,, and response matrices using SAS task rgsproc. Due to presence this st excess emission we limited our l studies to energies above 0.8 kev, limit suggested in EPIC calibration status report1. We included lower energies in case l ratios, as division should remove contribution excess emission, assuming that it is constant on time scales considered RESULTS Figure 4. Power density in 1 (upper panel) and 10 kev range (lower panel) fitted with Lorentzians. Figure 3. Energy dependence measured characteristic frequency (upper panel) and amplitude (lower panel). The BLN component is indicated by (red) crosses, QPO and its harmonic are indicated by (blue)3. stars XMM-Newton and data (green) diamonds, respectively. The observed behaviour corresponds to 3..1 Timing properties one normally seen during LHS. The st band PDS (1 kev) can be well fitted by one zero centered Lorentzian describing BLN component, one peaked Table 1. PDS parameters component a [Hz] rms [%] b [Hz] 0.8 kev 0c BLN BLN c 1.69 ± ± QPO QPO uh at low Figure 5. Energy dependence characteristic frequency (upper panel)ergy. and rms BLN (red cross), QPO (blue X), upper peaked noise ance (green circle), and lower peaked noise (magenta diamond). phas been times c 016 RAS, MNRAS 000, 1 10 fl H GS kev 0c BLN BLN c ± ± QPO QPO uh ± ± ± 0.4 H : fl at co var ia n ce ratios are observed Timing properties The broadband PDS ( 8 kev) can be well fitted by two zero centered Lorentzians describing BLN components and two peaked Lorentzians for QPO and its upper harmonic located at ± and ± Hz (Fig. ). In st band (0.8 kev) PDS same components are present and we do not see any hint additional disc variability at low frequencies. In 1 Stiele & Kong 016, MNRAS, 459, ± ± Notes: a : centroid frequency b : half width at half maximum (HWHM) c : zero centered Lorentzian GS 1354: decrease towards lower energies Figure 6. Covariance ratio, derived by dividing long timescale spectrum by short timescale one. In contrast to increase seen in e.g , Swift version 3.7, edited by M. J. S. Smith (ESAC) on behalf EPIC Consortium; available at J , which has been interpreted as additional disc variability on long scales (Wilkinson & Uttley 009, MNRAS 397, 666) c 016 RAS, MNRAS 000, 1 9 We fi & De ensu clude spect shift inclu powe ditio 1.3 k foreg 1. Swift cm is un to de

8 Energy param. 339/04 339/09 Sw1753/06 Sw1753/1/1 Sw1753/1/ GS1354 N dbb T in [kev] ± ± E cuto [kev] 7.6 ± ± 0. > ± ± 0.08 E fold [kev] ±. 9.4 ± 0.5 TBabs (diskbb + highecut nthcomp) GS : smaller inner disc radius; higher inner disc temperature Decrease in ratio cannot be explained with faint disc component Intrinsic variability disc? Driven by changes in Comptonizing component? Indicate changes in accretion geometry? Stiele & Yu 015, MNRAS 45, 3666 Stiele & Kong 016, MNRAS, 459, 4038

Covariance ratio possible explanations: Higher inclination H 1743-3 (around 80 ; Homan et al. 005; Miller et al. 006) compared to or BH LMXRBs (< 70 ; Motta et al.

9 Covariance ratio possible explanations: Higher inclination H (around 80 ; Homan et al. 005; Miller et al. 006) compared to or BH LMXRBs (< 70 ; Motta et al. 015) see H1743 more edge-on additional disc contribution on longer time scales does not show up Inclination GS unknown Presence/absence add. disc variability normal/ hard cov. ratio state only outburst cov. ratio Intensity Intensity Hardness Hardness

10 St-to-Hard transition Stiele & Kong 017, ApJ, arxiv: Stiele & Kong 017, ApJ, arxiv: Swift/XRT Swift/XRT monitoring 014/15 outburst XMM-Newton & NuSTAR observed source during stto-hard state transition

Covariance ratio Stiele & Kong 017, ApJ, arxiv:1706.08980 339 4 Stiele & Kong 017, ApJ, arxiv:1706.

time scale one Increase towards lower energies steepens long time scale variability at st energies becomes more and more important as source hardens

11 Covariance ratio Stiele & Kong 017, ApJ, arxiv: Stiele & Kong 017, ApJ, arxiv: outburst decay Averaged ratio increases during outburst decay Long time scale variability contributes more to overall variability than short time scale one Increase towards lower energies steepens long time scale variability at st energies becomes more and more important as source hardens Accretion disc instabilities (invoked by damped mass accretion rate variations or oscillations in disc truncation radius (Lyubarskii 1997; Meyer- Hmeister & Meyer 003)) get stronger when source hardens

12 Summary Covariance ratio 339-4, Swift J LHS outburst rise: ratio increases towards lower energies additional disc variability H , GS : ratio remains flat or decreases Observed during failed outburst; disc variability type outburst? Inclination? St-to-hard transition: ratio increases; increase steepens Accretion disc instabilities get stronger when source hardens

arxiv: v1 [astro-ph.he] 3 Aug 2010

arxiv: v1 [astro-ph.he] 3 Aug 2010 Mon. Not. R. Astron. Soc. 000, 000 000 (0000) Printed 4 August 2010 (MN LATEX style file v2.2) Fast variability as a tracer of accretion regimes in black hole transients arxiv:1008.0558v1 [astro-ph.he]