Skip to main content
SpringerLink
Log in

High-Frequency Variability in Neutron-Star Low-Mass X-ray Binaries

  • Chapter
  • First Online:
Timing Neutron Stars: Pulsations, Oscillations and Explosions

Part of the book series: Astrophysics and Space Science Library ((ASSL,volume 461))

Abstract

Binary systems with a neutron-star primary accreting from a companion star display variability in the X-ray band on time scales ranging from years to milliseconds. With frequencies of up to ∼1300 Hz, the kilohertz quasi-periodic oscillations (kHz QPOs) represent the fastest variability observed from any astronomical object. The sub-millisecond time scale of this variability implies that the kHz QPOs are produced in the accretion flow very close to the surface of the neutron star, providing a unique view of the dynamics of matter under the influence of some of the strongest gravitational fields in the Universe. This offers the possibility to probe some of the most extreme predictions of General Relativity, such as dragging of inertial frames and periastron precession at rates that are 16 orders of magnitude faster than those observed in the solar system and, ultimately, the existence of a minimum distance at which a stable orbit around a compact object is possible. Here we review the last 20 years of research on kHz QPOs, and we discuss the prospects for future developments in this field.

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Log in via an institution
Chapter
USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 129.00
Price excludes VAT (USA)
  • Available as EPUB and PDF
  • Read on any device
  • Instant download
  • Own it forever
Hardcover Book
USD 169.99
Price excludes VAT (USA)
  • Durable hardcover edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Notes

  1. 1.

    Phase lags equal to Δϕ ± 2nπ, with n any integer number, cannot be distinguished from a phase lag Δϕ.

  2. 2.

    As explained in Sect. 6.4, in a modified version of the sonic-point model the frequency difference between the kHz QPOs can also be equal to half the neutron-star spin frequency [87].

  3. 3.

    This is possibly also the case for the upper kHz QPO, and all other QPO signals in these sources.

References

  1. M.A. Abramowicz, W. Kluźniak, A precise determination of black hole spin in GRO J1655-40. Astron. Astrophys. 374, L19–L20 (2001)

    Article  ADS  Google Scholar 

  2. M.A. Abramowicz, T. Bulik, M. Bursa, W. Kluźniak, Evidence for a 2:3 resonance in Sco X-1 kHz QPOs. Astron. Astrophys. 404, L21–L24 (2003)

    Article  ADS  Google Scholar 

  3. P.C. Agrawal, A broad spectral band Indian Astronomy satellite ‘Astrosat’. Adv. Space Res. 38(12), 2989–2994 (2006)

    Article  ADS  Google Scholar 

  4. M. Ali Alpar, QPO frequency derivative-frequency correlation indicates non-Keplerian boundary layer with a maximum in rotation rate. Mon. Not. R. Astron. Soc. 462(1), L98–L100 (2016)

    Article  ADS  Google Scholar 

  5. M.A. Alpar, D. Psaltis, The highest dynamical frequency in the inner region of an accretion disc. Mon. Not. R. Astron. Soc. 391(3), 1472–1476 (2008)

    Article  ADS  Google Scholar 

  6. M.A. Alpar, J. Shaham, Is GX5 - 1 a millisecond pulsar? Nature 316(6025), 239–241 (1985)

    Article  ADS  Google Scholar 

  7. D. Altamirano, M. van der Klis, M. Méndez, S. Migliari, P.G. Jonker, A. Tiengo, W. Zhang, The island state of the atoll source 4U 1820-30. Astrophys. J. 633(1), 358–366 (2005)

    Article  ADS  Google Scholar 

  8. D. Altamirano, M. van der Klis, M. Méndez, P.G. Jonker, M. Klein-Wolt, W.H.G. Lewin, X-ray time variability across the atoll source states of 4U 1636-53. Astrophys. J. 685(1), 436–450 (2008)

    Article  ADS  Google Scholar 

  9. D. Altamirano, M. van der Klis, M. Méndez, R. Wijnand, C. Markwardt, J. Swank, Discovery of kilohertz quasi-periodic oscillations and state transitions in the low-mass X-ray binary 1E 1724-3045 (Terzan 2). Astrophys. J. 687(1), 488–504 (2008)

    Article  ADS  Google Scholar 

  10. J.M. Bardeen, W.H. Press, S.A. Teukolsky, Rotating black holes: locally nonrotating frames, energy extraction, and scalar synchrotron radiation. Astrophys. J. 178, 347–370 (1972)

    Article  ADS  Google Scholar 

  11. D. Barret, Soft lags in neutron star kHz quasi-periodic oscillations: evidence for reverberation? Astrophys. J. 770(1), 9 (2013)

    Google Scholar 

  12. D. Barret, G. Vedrenne, Hard X-ray emission from weakly magnetized neutron stars. Astrophys. J. Suppl. 92, 505 (1994)

    Article  ADS  Google Scholar 

  13. D. Barret, W. Kluźniak, J.F. Olive, S. Paltani, G.K. Skinner, On the high coherence of kHz quasi-periodic oscillations. Mon. Not. R. Astron. Soc. 357(4), 1288–1294 (2005)

    Article  ADS  Google Scholar 

  14. D. Barret, J.-F. Olive, M.C. Miller, An abrupt drop in the coherence of the lower kHz quasi-periodic oscillations in 4U 1636-536. Mon. Not. R. Astron. Soc. 361(3), 855–860 (2005)

    Article  ADS  Google Scholar 

  15. D. Barret, J.-F. Olive, M.C. Miller, The coherence of kilohertz quasi-periodic oscillations in the X-rays from accreting neutron stars. Mon. Not. R. Astron. Soc. 370(3), 1140–1146 (2006)

    Article  ADS  Google Scholar 

  16. D. Barret, M. Bachetti, M.C. Miller, The drop of the coherence of the lower kilohertz quasi-periodic brightness variations is also observed in XTE J1701-462. Astrophys. J. 728(1), 9 (2011)

    Google Scholar 

  17. T.M. Belloni, D. Altamirano, High-frequency quasi-periodic oscillations from GRS 1915+105. Mon. Not. R. Astron. Soc. 432(1), 10–18 (2013)

    Article  ADS  Google Scholar 

  18. T. Belloni, G. Hasinger, An atlas of aperiodic variability in HMXB. Astron. Astrophys. 230, 103–119 (1990)

    ADS  Google Scholar 

  19. T. Belloni, M. Méndez, J. Homan, The distribution of kHz QPO frequencies in bright low mass X-ray binaries. Astron. Astrophys. 437(1), 209–216 (2005)

    Article  ADS  Google Scholar 

  20. T. Belloni, J. Homan, S. Motta, E. Ratti, M. Méndez, Rossi XTE monitoring of 4U1636-53 - I. Long-term evolution and kHz quasi-periodic oscillations. Mon. Not. R. Astron. Soc. 379(1), 247–252 (2007)

    Google Scholar 

  21. T. Belloni, M. Méndez, J. Homan, On the kHz QPO frequency correlations in bright neutron star X-ray binaries. Mon. Not. R. Astron. Soc. 376(3), 1133–1138 (2007)

    Article  ADS  Google Scholar 

  22. T.M. Belloni, A. Sanna, M. Méndez, High-frequency quasi-periodic oscillations in black hole binaries. Mon. Not. R. Astron. Soc. 426(3), 1701–1709 (2012)

    Article  ADS  Google Scholar 

  23. J.S. Bendat, A.G. Piersol, Random Data: Analysis and Measurement Procedures, 4th edn. (Wiley, Hoboken, 2010)

    Book  MATH  Google Scholar 

  24. M. Berger, M. van der Klis, J. van Paradijs, W.H.G. Lewin, F. Lamb, B. Vaughan, E. Kuulkers, T. Augusteijn, W. Zhang, F.E. Marshall, J.H. Swank, I. Lapidus, J.C. Lochner, T.E. Strohmayer, Discovery of 800 HZ quasi-periodic oscillations in 4U 1608-52. Astrophys. J. Lett. 469, L13 (1996)

    Article  ADS  Google Scholar 

  25. S. Bhattacharyya, Ways to constrain neutron star equation of state models using relativistic disc lines. Mon. Not. R. Astron. Soc. 415(4), 3247–3252 (2011)

    Article  ADS  Google Scholar 

  26. S. Bhattacharyya, T.E. Strohmayer, Evidence of a broad relativistic iron line from the neutron star low-mass X-ray binary Serpens X-1. Astrophys. J. Lett. 664(2), L103–L106 (2007)

    Article  ADS  Google Scholar 

  27. M. Boutelier, D. Barret, M.C. Miller, kHz quasi-periodic oscillations in the low-mass X-ray binary 4U 0614+09. Mon. Not. R. Astron. Soc. 399(4), 1901–1906 (2009)

    Article  ADS  Google Scholar 

  28. S. Boutloukos, M. van der Klis, D. Altamirano, M. Klein-Wolt, R. Wijnands, P.G. Jonker, R.P. Fender, Discovery of twin kHz QPOs in the peculiar X-ray binary circinus X-1. Astrophys. J. 653(2), 1435–1444 (2006)

    Article  ADS  Google Scholar 

  29. J. Brainerd, F.K. Lamb, Effect of an electron scattering cloud on X-ray oscillations produced by beaming. Astrophys. J. Lett. 317, L33 (1987)

    Article  ADS  Google Scholar 

  30. E.M. Cackett, Are the kHz QPO lags in neutron star 4U 1608-52 due to reverberation? Astrophys. J. 826(2), 103 (2016)

    Google Scholar 

  31. E.M. Cackett, J.M. Miller, S. Bhattacharyya, J.E. Grindlay, J. Homan, M. van der Klis, M.C. Miller, T.E. Strohmayer, R. Wijnands, Relativistic iron emission lines in neutron star low-mass X-ray binaries as probes of neutron star radii. Astrophys. J. 674(1), 415–420 (2008)

    Article  ADS  Google Scholar 

  32. E.M. Cackett, D. Altamirano, A. Patruno, J.M. Miller, M. Reynolds, M. Linares, R. Wijnands, Broad relativistic iron emission line observed in SAX J1808.4-3658. Astrophys. J. Lett. 694(1), L21–L25 (2009)

    Google Scholar 

  33. E.M. Cackett, J.M. Miller, D.R. Ballantyne, D. Barret, S. Bhattacharyya, M. Boutelier, M.C. Miller, T.E. Strohmayer, R. Wijnands, Relativistic lines and reflection from the inner accretion disks around neutron stars. Astrophys. J. 720(1), 205–225 (2010)

    Article  ADS  Google Scholar 

  34. P. Casella, T. Belloni, L. Stella, The ABC of low-frequency quasi-periodic oscillations in black hole candidates: analogies with Z sources. Astrophys. J. 629(1), 403–407 (2005)

    Article  ADS  Google Scholar 

  35. D.J. Christian, J.H. Swank, The survey of low-mass X-ray binaries with the Einstein observatory solid-state spectrometer and monitor proportional counter. Astrophys. J. Suppl. 109(1), 177–224 (1997)

    Article  ADS  Google Scholar 

  36. B.M. Coughenour, E.M. Cackett, P. Peille, J.S. Troyer, Modeling the upper kHz QPOs of 4U 1728-34 with X-ray reverberation. Astrophys. J. 889(2), 136 (2020)

    Google Scholar 

  37. M.G.B. de Avellar, M. Méndez, A. Sanna, J.E. Horvath, Time lags of the kilohertz quasi-periodic oscillations in the low-mass X-ray binaries 4U 1608-52 and 4U 1636-53. Mon. Not. R. Astron. Soc. 433(4), 3453–3463 (2013)

    ADS  Google Scholar 

  38. M.G.B. de Avellar, M. Méndez, D. Altamirano, A. Sanna, G. Zhang, Phase lags of quasi-periodic oscillations across source states in the low-mass X-ray binary 4U 1636-53. Mon. Not. R. Astron. Soc. 461(1), 79–92 (2016)

    Article  ADS  Google Scholar 

  39. B. De Marco, G. Ponti, T. Muñoz-Darias, K. Nand ra, Tracing the reverberation lag in the hard state of black hole X-ray binaries. Astrophys. J. 814(1), 50 (2015)

    Google Scholar 

  40. T. Di Salvo, M. Méndez, M. van der Klis, E. Ford, N.R. Robba, Study of the temporal behavior of 4U 1728-34 as a function of its position in the color-color diagram. Astrophys. J. 546(2), 1107–1120 (2001)

    Article  ADS  Google Scholar 

  41. T. Di Salvo, N.R. Robba, R. Iaria, L. Stella, L. Burderi, G.L. Israel, Detection of a hard tail in the X-ray spectrum of the Z source GX 349+2. Astrophys. J. 554(1), 49–55 (2001)

    Article  ADS  Google Scholar 

  42. T. Di Salvo, M. Méndez, M. van der Klis, On the correlated spectral and timing properties of 4U 1636-53: an atoll source at high accretion rates. Astron. Astrophys. 406, 177–192 (2003)

    Article  ADS  Google Scholar 

  43. T. Di Salvo, R. Iaria, M. Méndez, L. Burderi, G. Lavagetto, N.R. Robba, L. Stella, M. van der Klis, A broad iron line in the Chandra high energy transmission grating spectrum of 4U 1705-44. Astrophys. J. Lett. 623(2), L121–L124 (2005)

    Article  ADS  Google Scholar 

  44. T. di Salvo, A. D’Aí, R. Iaria, L. Burderi, M. Dovčiak, V. Karas, G. Matt, A. Papitto, S. Piraino, A. Riggio, N.R. Robba, A. Santangelo, A relativistically smeared spectrum in the neutron star X-ray binary 4U 1705-44: looking at the inner accretion disc with X-ray spectroscopy. Mon. Not. R. Astron. Soc. 398(4), 2022–2027 (2009)

    Article  ADS  Google Scholar 

  45. T. Di Salvo, R. Iaria, M. Matranga, L. Burderi, A. D’Aí, E. Egron, A. Papitto, A. Riggio, N.R. Robba, Y. Ueda, Suzaku broad-band spectrum of 4U 1705-44: probing the reflection component in the hard state. Mon. Not. R. Astron. Soc. 449(3), 2794–2802 (2015)

    Article  ADS  Google Scholar 

  46. E. Egron, T. Di Salvo, S. Motta, L. Burderi, A. Papitto, R. Duro, A. D’Aì, A. Riggio, T. Belloni, R. Iaria, N.R. Robba, S. Piraino, A. Santangelo, Testing reflection features in 4U 1705-44 with XMM-Newton, BeppoSAX, and RXTE in the hard and soft states. Astron. Astrophys. 550, A5 (2013)

    Article  Google Scholar 

  47. M.H. Erkut, D. Psaltis, M.A. Alpar, Quasi-periodic oscillations as global hydrodynamic modes in the boundary layers of viscous accretion disks. Astrophys. J. 687(2), 1220–1229 (2008)

    Article  ADS  Google Scholar 

  48. A.C. Fabian, M.J. Rees, L. Stella, N.E. White, X-ray fluorescence from the inner disc in Cygnus X-1. Mon. Not. R. Astron. Soc. 238, 729–736 (1989)

    Article  ADS  Google Scholar 

  49. A.C. Fabian, A. Zoghbi, R.R. Ross, P. Uttley, L.C. Gallo, W.N. Brandt, A.J. Blustin, T. Boller, M.D. Caballero-Garcia, J. Larsson, J.M. Miller, G. Miniutti, G. Ponti, R.C. Reis, C.S. Reynolds, Y. Tanaka, A.J. Young, Broad line emission from iron K- and L-shell transitions in the active galaxy 1H0707-495. Nature 459(7246), 540–542 (2009)

    Article  ADS  Google Scholar 

  50. E. Ford, P. Kaaret, M. Tavani, D. Barret, P. Bloser, J. Grindlay, B.A. Harmon, W.S. Paciesas, S.N. Zhang, Evidence from quasi-periodic oscillations for a millisecond pulsar in the low-mass X-ray binary 4U 0614+091. Astrophys. J. Lett. 475(2), L123–L126 (1997)

    Article  ADS  Google Scholar 

  51. E.C. Ford, M. van der Klis, J. van Paradijs, M. Méndez, R. Wijnands, P. Kaaret, Discovery of a second kilohertz QPO in the X-ray binary 4U 1735-44. Astrophys. J. Lett. 508(2), L155–L158 (1998)

    Article  ADS  Google Scholar 

  52. J. Frank, A. King, D.J. Raine, Accretion Power in Astrophysics, 3rd edn. (Cambridge University Press, Cambridge, 2002)

    Book  Google Scholar 

  53. K.C. Gendreau, Z. Arzoumanian, T. Okajima, The Neutron star Interior Composition ExploreR (NICER): an explorer mission of opportunity for soft X-ray timing spectroscopy, in Proceedings of the SPIE, vol. 8443. Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, September 2012, p. 844313

    Google Scholar 

  54. M. Gierliński, C. Done, The X-ray spectrum of the atoll source 4U 1608-52. Mon. Not. R. Astron. Soc. 337(4), 1373–1380 (2002)

    Article  ADS  Google Scholar 

  55. M. Gierliński, C. Done, K. Page, X-ray irradiation in XTE J1817-330 and the inner radius of the truncated disc in the hard state. Mon. Not. R. Astron. Soc. 388(2), 753–760 (2008)

    Article  ADS  Google Scholar 

  56. M. Gilfanov, M. Revnivtsev, S. Molkov, Boundary layer, accretion disk and X-ray variability in the luminous LMXBs. Astron. Astrophys. 410, 217–230 (2003)

    Article  ADS  Google Scholar 

  57. J. Homan, M. van der Klis, A 695 HZ quasi-periodic oscillation in the low-mass X-ray binary EXO 0748-676. Astrophys. J. 539(2), 847–850 (2000)

    Article  ADS  Google Scholar 

  58. J. Homan, M. van der Klis, P.G. Jonker, R. Wijnands, E. Kuulkers, M. Méndez, W.H.G. Lewin, RXTE observations of the neutron star low-mass X-ray binary GX 17+2: correlated X-ray spectral and timing behavior. Astrophys. J. 568(2), 878–900 (2002)

    Article  ADS  Google Scholar 

  59. J. Homan, T. Belloni, M. van der Klis, P. Casella, M. Mendez, W. Lewin, R. Fender, E. Gallo, N. Gehrels, Spectral evolution and kHz QPOs in the transient Z source XTE J1701-462. Astron. Telegram 748, 1 (2006)

    ADS  Google Scholar 

  60. J. Homan, M. van der Klis, R. Wijnands, T. Belloni, R. Fender, M. Klein-Wolt, P. Casella, M. Méndez, E. Gallo, W.H.G. Lewin, N. Gehrels, Rossi X-ray timing explorer observations of the first transient Z source XTE J1701-462: shedding new light on mass accretion in luminous neutron star X-ray binaries. Astrophys. J. 656(1), 420–430 (2007)

    Article  ADS  Google Scholar 

  61. J. Homan, R. Wijnands, D. Altamirano, T. Belloni, Rapid decay of the neutron star transient XTE J1701-462. Astron. Telegram 1165, 1 (2007)

    ADS  Google Scholar 

  62. J. Homan, M. van der Klis, J.K. Fridriksson, R.A. Remillard, R. Wijnands, M. Méndez, D. Lin, D. Altamirano, P. Casella, T.M. Belloni, W.H.G. Lewin, XTE J1701-462 and its implications for the nature of subclasses in low-magnetic-field neutron star low-mass X-ray binaries. Astrophys. J. 719(1), 201–212 (2010)

    Article  ADS  Google Scholar 

  63. R. Iaria, A. D’Aí, T. di Salvo, N.R. Robba, A. Riggio, A. Papitto, L. Burderi, A ionized reflecting skin above the accretion disk of GX 349+2. Astron. Astrophys. 505(3), 1143–1151 (2009)

    Article  ADS  Google Scholar 

  64. R. Iaria, T. Di Salvo, M. Del Santo, F. Pintore, A. Sanna, A. Papitto, L. Burderi, A. Riggio, A.F. Gambino, M. Matranga, Study of the reflection spectrum of the LMXB 4U 1702-429. Astron. Astrophys. 596, A21 (2016)

    Article  Google Scholar 

  65. A. Ingram, Error formulae for the energy-dependent cross-spectrum. Mon. Not. R. Astron. Soc. 489(3), 3927–3938 (2019)

    ADS  Google Scholar 

  66. A. Ingram, M. van der Klis, M. Middleton, D. Altamirano, P. Uttley, Tomographic reflection modelling of quasi-periodic oscillations in the black hole binary H 1743-322. Mon. Not. R. Astron. Soc. 464(3), 2979–2991 (2017)

    Article  ADS  Google Scholar 

  67. P.G. Jonker, M. Méndez, M. van der Klis, Discovery of a new, third kilohertz quasi-periodic oscillation in 4U 1608-52, 4U 1728-34, and 4U 1636-53: sidebands to the lower kilohertz quasi-periodic oscillation? Astrophys. J. Lett. 540(1), L29–L32 (2000)

    Article  ADS  Google Scholar 

  68. P.G. Jonker, M. van der Klis, R. Wijnands, J. Homan, J. van Paradijs, M. Méndez, E.C. Ford, E. Kuulkers, F.K. Lamb, The power spectral properties of the Z source GX 340+0. Astrophys. J. 537(1), 374–386 (2000)

    Article  ADS  Google Scholar 

  69. P.G. Jonker, M. van der Klis, J. Homan, M. Méndez, W.H.G. Lewin, R. Wijnands, W. Zhang, Low- and high-frequency variability as a function of spectral properties in the bright X-ray binary GX 5-1. Mon. Not. R. Astron. Soc. 333(3), 665–678 (2002)

    Article  ADS  Google Scholar 

  70. P.G. Jonker, M. Méndez, M. van der Klis, Kilohertz quasi-periodic oscillations difference frequency exceeds inferred spin frequency in 4U 1636-53. Mon. Not. R. Astron. Soc. 336(1), L1–L5 (2002)

    Article  ADS  Google Scholar 

  71. P.G. Jonker, M. Méndez, M. van der Klis, Sidebands to the lower kilohertz quasi-periodic oscillation in 4U 1636-53. Mon. Not. R. Astron. Soc. 360(3), 921–925 (2005)

    Article  ADS  Google Scholar 

  72. P. Kaaret, W. Yu, E.C. Ford, S.N. Zhang, Correlation between fast quasi-periodic oscillations and X-ray spectral shape in Atoll sources. Astrophys. J. Lett. 497(2), L93–L96 (1998)

    Article  ADS  Google Scholar 

  73. P. Kaaret, S. Piraino, E.C. Ford, A. Santangelo, Discovery of microsecond soft lags in the X-ray emission of the Atoll source 4U 1636-536. Astrophys. J. Lett. 514(1), L31–L33 (1999)

    Article  ADS  Google Scholar 

  74. E. Kara, J.F. Steiner, A.C. Fabian, E.M. Cackett, P. Uttley, R.A. Remillard, K.C. Gendreau, Z. Arzoumanian, D. Altamirano, S. Eikenberry, T. Enoto, J. Homan, J. Neilsen, A.L. Stevens, The corona contracts in a black-hole transient. Nature 565(7738), 198–201 (2019)

    Article  ADS  Google Scholar 

  75. K. Karpouzas, M. Méndez, E. ro M. Ribeiro, D. Altamirano, O. Blaes, F. García, The comptonizing medium of the neutron star in 4U 1636 - 53 through its lower kilohertz quasi-periodic oscillations. Mon. Not. R. Astron. Soc. 492(1), 1399–1415 (2020)

    Google Scholar 

  76. S. Kato, Trapped one-armed corrugation waves and QPO’s. Publ. Astron. Soc. Jpn. 42, 99–113 (1990)

    ADS  Google Scholar 

  77. S. Kato, J. Fukue, Trapped radial oscillations of gaseous disks around a black hole. Publ. Astron. Soc. Jpn. 32, 377 (1980)

    Article  ADS  Google Scholar 

  78. W. Kluźniak, M.A. Abramowicz, Resonant oscillations of accretion flow and Khz QPOS. Astrophys. Space Sci. 300(1–3), 143–148 (2005)

    ADS  MATH  Google Scholar 

  79. W. Kluzniak, P. Michelson, R.V. Wagoner, Determining the properties of accretion-gap neutron stars. Astrophys. J. 358, 538 (1990)

    Article  ADS  Google Scholar 

  80. W. Kluźniak, M.A. Abramowicz, S. Kato, W.H. Lee, N. Stergioulas, Nonlinear resonance in the accretion disk of a millisecond pulsar. Astrophys. J. Lett. 603(2), L89–L92 (2004)

    Article  ADS  Google Scholar 

  81. A.S. Kompaneets, The establishment of thermal equilibrium between quanta and electrons. Sov. J. Exp. Theor. Phys. 4(5), 730–737 (1957)

    ADS  MathSciNet  MATH  Google Scholar 

  82. N. Kumar, R. Misra, Energy dependent time delays of kHz oscillations due to thermal Comptonization. Mon. Not. R. Astron. Soc. 445(3), 2818–2824 (2014)

    Article  ADS  MathSciNet  Google Scholar 

  83. N. Kumar, R. Misra, Constraining the size of the Comptonizing medium by modelling the energy-dependent time lags of kHz QPOs of neutron star system. Mon. Not. R. Astron. Soc. 461(3), 2580–2588 (2016)

    Article  ADS  Google Scholar 

  84. N.D. Kylafis, G.S. Klimis, Effects of electron scattering on the oscillations of an X-ray source. Astrophys. J. 323, 678 (1987)

    Article  ADS  Google Scholar 

  85. D. Lai, D. Tsang, Corotational instability of inertial-acoustic modes in black hole accretion discs and quasi-periodic oscillations. Mon. Not. R. Astron. Soc. 393(3), 979–991 (2009)

    Article  ADS  Google Scholar 

  86. F.K. Lamb, M.C. Miller, Changing frequency separation of kilohertz quasi-periodic oscillations in the sonic-point beat-frequency model. Astrophys. J. 554(2), 1210–1215 (2001)

    Article  ADS  Google Scholar 

  87. F.K. Lamb, M.C. Miller, Sonic-point and spin-resonance model of the kilohertz QPO pairs. arXiv e-prints, astro-ph/0308179, August 2003

    Google Scholar 

  88. F.K. Lamb, N. Shibazaki, M.A. Alpar, J. Shaham, Quasi-periodic oscillations in bright galactic-bulge X-ray sources. Nature 317(6039), 681–687 (1985)

    Article  ADS  Google Scholar 

  89. L.D. Landau, E.M. Lifshitz, Mechanics, Volume 1, 3rd edn. Course of Theoretical Physics (Butterworth-Heinemann, Oxford, 1976)

    Google Scholar 

  90. D.A. Leahy, W. Darbro, R.F. Elsner, M.C. Weisskopf, P.G. Sutherland, S. Kahn, J.E. Grindlay, On searches for pulsed emission with application to four globular cluster X-ray sources : NGC 1851, 6441, 6624 and 6712. Astrophys. J. 266, 160–170 (1983)

    Article  ADS  Google Scholar 

  91. H.C. Lee, G.S. Miller, Comptonization and QPO origins in accreting neutron star systems. Mon. Not. R. Astron. Soc. 299(2), 479–487 (1998)

    Article  ADS  Google Scholar 

  92. H.C. Lee, R. Misra, R.E. Taam, A compton upscattering model for soft lags in the lower kilohertz quasi-periodic oscillation in 4U 1608-52. Astrophys. J. Lett. 549(2), L229–L232 (2001)

    Article  ADS  Google Scholar 

  93. W.H. Lee, M.A. Abramowicz, W. Kluźniak, Resonance in forced oscillations of an accretion disk and kilohertz quasi-periodic oscillations. Astrophys. J. Lett. 603(2), L93–L96 (2004)

    Article  ADS  Google Scholar 

  94. D. Lin, R.A. Remillard, J. Homan, Evaluating spectral models and the X-ray states of neutron star X-ray transients. Astrophys. J. 667(2), 1073–1086 (2007)

    Article  ADS  Google Scholar 

  95. D. Lin, R.A. Remillard, J. Homan, Spectral states of XTE J1701 - 462: link between Z and Atoll sources. Astrophys. J. 696(2), 1257–1277 (2009)

    Article  ADS  Google Scholar 

  96. M. Linares, M. van der Klis, D. Altamirano, C.B. Markwardt, Discovery of kilohertz quasi-periodic oscillations and shifted frequency correlations in the accreting millisecond pulsar XTE J1807-294. Astrophys. J. 634(2), 1250–1260 (2005)

    Article  ADS  Google Scholar 

  97. R.M. Ludlam, J.M. Miller, Z. Arzoumanian, P.M. Bult, E.M. Cackett, D. Chakrabarty, T. Dauser, T. Enoto, A.C. Fabian, J.A. García, K.C. Gendreau, S. Guillot, J. Homan, G.K. Jaisawal, L. Keek, B. La Marr, C. Malacaria, C.B. Markwardt, J.F. Steiner, T.E. Strohmayer, Detection of reflection features in the neutron star low-mass X-ray binary serpens X-1 with NICER. Astrophys. J. Lett. 858(1), L5 (2018)

    Google Scholar 

  98. R.M. Ludlam, J.M. Miller, D. Barret, E.M. Cackett, B.M. Coughenour, T. Dauser, N. Degenaar, J.A. García, F.A. Harrison, F. Paerels, NuSTAR observations of the accreting Atolls GX 3+1, 4U 1702-429, 4U 0614+091, and 4U 1746-371. Astrophys. J. 873(1), 99 (2019)

    Google Scholar 

  99. M. Lyu, M. Méndez, A. Sanna, J. Homan, T. Belloni, B. Hiemstra, Iron-line and continuum variations in the XMM-Newton and Suzaku spectra of the neutron-star low-mass X-ray binary 4U 1636-53. Mon. Not. R. Astron. Soc. 440(2), 1165–1178 (2014)

    Article  ADS  Google Scholar 

  100. J. Malzac, A. Merloni, A.C. Fabian, Jet-disc coupling through a common energy reservoir in the black hole XTE J1118+480. Mon. Not. R. Astron. Soc. 351(1), 253–264 (2004)

    Article  ADS  Google Scholar 

  101. G. Mastroserio, A. Ingram, M. van der Klis, Multi-time-scale X-ray reverberation mapping of accreting black holes. Mon. Not. R. Astron. Soc. 475(3), 4027–4042 (2018)

    Article  ADS  Google Scholar 

  102. S.M. Mazzola, R. Iaria, T. Di Salvo, M. Del Santo, A. Sanna, A.F. Gambino, A. Riggio, A. Segreto, L. Burderi, A. Santangelo, N. D’Amico, A broadband spectral analysis of 4U 1702-429 using XMM-Newton and BeppoSAX data. Astron. Astrophys. 621, A89 (2019)

    Article  Google Scholar 

  103. M. Méndez, On the maximum amplitude and coherence of the kilohertz quasi-periodic oscillations in low-mass X-ray binaries. Mon. Not. R. Astron. Soc. 371(4), 1925–1938 (2006)

    Article  ADS  Google Scholar 

  104. M. Méndez, T. Belloni, Is there a link between the neutron-star spin and the frequency of the kilohertz quasi-periodic oscillations? Mon. Not. R. Astron. Soc. 381(2), 790–796 (2007)

    Article  ADS  Google Scholar 

  105. M. Méndez, M. van der Klis, Precise measurements of the kilohertz quasi-periodic oscillations in 4U 1728-34. Astrophys. J. Lett. 517(1), L51–L54 (1999)

    Article  ADS  Google Scholar 

  106. M. Méndez, M. van der Klis, The harmonic and sideband structure of the kilohertz quasi-periodic oscillations in Sco X-1. Mon. Not. R. Astron. Soc. 318(3), 938–942 (2000)

    Article  ADS  Google Scholar 

  107. M. Méndez, M. van der Klis, R. Wijnands, E.C. Ford, J. van Paradijs, B.A. Vaughan, Kilohertz quasi-periodic oscillation peak separation is not constant in the Atoll source 4U 1608-52. Astrophys. J. Lett. 505(1), L23–L26 (1998)

    Article  ADS  Google Scholar 

  108. M. Méndez, M. van der Klis, J. van Paradijs, Difference frequency of kilohertz QPOs not equal to half the burst oscillation frequency in 4U 1636-53. Astrophys. J. Lett. 506(2), L117–L119 (1998)

    Article  ADS  Google Scholar 

  109. M. Méndez, M. van der Klis, E.C. Ford, R. Wijnand, J. van Paradijs, Dependence of the frequency of the kilohertz quasi-periodic oscillationson X-ray count rate and colors in 4U 1608-52. Astrophys. J. Lett. 511(1), L49–L52 (1999)

    Article  ADS  Google Scholar 

  110. M. Méndez, M. van der Klis, E.C. Ford, The amplitude of the kilohertz quasi-periodic oscillations in 4U 1728-34, 4U 1608-52, and Aquila X-1, as a function of X-ray intensity. Astrophys. J. 561(2), 1016–1026 (2001)

    ADS  Google Scholar 

  111. A. Merloni, A.C. Fabian, Accretion disc coronae as magnetic reservoirs. Mon. Not. R. Astron. Soc. 321(3), 549–552 (2001)

    Article  ADS  Google Scholar 

  112. M.C. Miller, Attenuation of beaming oscillations near neutron stars. Astrophys. J. 537(1), 342–350 (2000)

    Article  ADS  Google Scholar 

  113. M.C. Miller, Interpreting QPOs from accreting neutron stars, in X-ray Timing 2003: Rossi and Beyond, vol. 714, ed. by P. Kaaret, F.K. Lamb, J.H. Swank. American Institute of Physics Conference Series, July 2004, pp. 365–370

    Google Scholar 

  114. M.C. Miller, F.K. Lamb, G.B. Cook, Effects of rapid stellar rotation on equation-of-state constraints derived from quasi-periodic brightness oscillations. Astrophys. J. 509(2), 793–801 (1998)

    Article  ADS  Google Scholar 

  115. M.C. Miller, F.K. Lamb, D. Psaltis, Sonic-point model of kilohertz quasi-periodic brightness oscillations in low-mass X-ray binaries. Astrophys. J. 508(2), 791–830 (1998)

    Article  ADS  Google Scholar 

  116. M.C. Miller, F.K. Lamb, D. Psaltis, Constraints on the equation of state of neutron star matter from observations of kilohertz QPOs. Nucl. Phys. B Proc. Suppl. 69(1–3), 123–128 (1999)

    Article  ADS  Google Scholar 

  117. J.M. Miller, M.L. Parker, F. Fuerst, M. Bachetti, D. Barret, B.W. Grefenstette, S. Tendulkar, F.A. Harrison, S.E. Boggs, D. Chakrabarty, F.E. Christensen, W.W. Craig, A.C. Fabian, C.J. Hailey, L. Natalucci, F. Paerels, V. Rana, D.K. Stern, J.A. Tomsick, W.W. Zhang, Constraints on the neutron star and inner accretion flow in serpens X-1 using NuSTAR. Astrophys. J. Lett. 779(1), L2 (2013)

    Google Scholar 

  118. S. Miyamoto, K. Kimura, S. Kitamoto, T. Dotani, K. Ebisawa, X-ray variability of GX 339-4 in its very high state. Astrophys. J. 383, 784 (1991)

    Article  ADS  Google Scholar 

  119. E.H. Morgan, R.A. Remillard, J. Greiner, RXTE observations of QPOs in the black hole candidate GRS 1915+105. Astrophys. J. 482(2), 993–1010 (1997)

    Article  ADS  Google Scholar 

  120. A. Mukherjee, S. Bhattacharyya, Highly coherent kilohertz quasi-periodic oscillations from the neutron star X-ray binary EXO 1745-248. Astrophys. J. Lett. 730(2), L32 (2011)

    Google Scholar 

  121. A. Mukherjee, S. Bhattacharyya, Fractional amplitude of kilohertz quasi-periodic oscillation from 4U 1728-34: evidence of decline at higher energies. Astrophys. J. 756(1), 55 (2012)

    Google Scholar 

  122. K. Nandra, D. Barret, X. Barcons, A. Fabian, J.-W. den Herder, L. Piro, M. Watson, C. Adami, J. Aird, J.M. Afonso, D. Alexander, C. Argiroffi, L. Amati, M. Arnaud, J.-L. Atteia, M. Audard, C. Badenes, J. Ballet, L. Ballo, A. Bamba, A. Bhardwaj, E. Stefano Battistelli, W. Becker, M. De Becker, E. Behar, S. Bianchi, V. Biffi, L. Bîrzan, F. Bocchino, S. Bogdanov, L. Boirin, T. Boller, S. Borgani, K. Borm, N. Bouché, H. Bourdin, R. Bower, V. Braito, E. Branchini, G. Branduardi-Raymont, J. Bregman, L. Brenneman, M. Brightman, M. Brüggen, J. Buchner, E. Bulbul, M. Brusa, M. Bursa, A. Caccianiga, E. Cackett, S. Campana, Cappelluti, M. Cappi, F. Carrera, M. Ceballos, F. Christensen, Y.-H. Chu, E. Churazov, N. Clerc, S. Corbel, A. Corral, A. Comastri, E. Costantini, J. Croston, M. Dadina, A. D’Ai, A. Decourchelle, R. Della Ceca, K. Dennerl, K. Dolag, C. Done, M. Dovciak, J. Drake, D. Eckert, A. Edge, S. Ettori, Y. Ezoe, E. Feigelson, R. Fender, C. Feruglio, A. Finoguenov, F. Fiore, M. Galeazzi, S. Gallagher, P. Gandhi, M. Gaspari, F. Gastaldello, A. Georgakakis, I. Georgantopoulos, M. Gilfanov, M. Gitti, R. Gladstone, R. Goosmann, E. Gosset, N. Grosso, M. Guedel, M. Guerrero, F. Haberl, M. Hardcastle, S. Heinz, A. Alonso Herrero, A. Hervé, M. Holmstrom, K. Iwasawa, P. Jonker, J. Kaastra, E. Kara, V. Karas, J. Kastner, A. King, D. Kosenko, D. Koutroumpa, R. Kraft, I. Kreykenbohm, R. Lallement, G. Lanzuisi, J. Lee, M. Lemoine-Goumard, A. Lobban, G. Lodato, L. Lovisari, S. Lotti, I. McCharthy, B. McNamara, A. Maggio, R. Maiolino, B. De Marco, D. de Martino, S. Mateos, G. Matt, B. Maughan, P. Mazzotta, M. Mendez, A. Merloni, G. Micela, M. Miceli, R. Mignani, J. Miller, G. Miniutti, S. Molendi, R. Montez, A. Moretti, C. Motch, Y. Nazé, J. Nevalainen, F. Nicastro, P. Nulsen, T. Ohashi, P. O’Brien, J. Osborne, L. Oskinova, F. Pacaud, F. Paerels, M. Page, I. Papadakis, G. Pareschi, R. Petre, P.-O. Petrucci, E. Piconcelli, I. Pillitteri, C. Pinto, J. de Plaa, E. Pointecouteau, T. Ponman, G. Ponti, D. Porquet, K. Pounds, G. Pratt, P. Predehl, D. Proga, D. Psaltis, D. Rafferty, M. Ramos-Ceja, P. Ranalli, E. Rasia, A. Rau, G. Rauw, N. Rea, A. Read, J. Reeves, T. Reiprich, M. Renaud, C. Reynolds, G. Risaliti, J. Rodriguez, P. Rodriguez Hidalgo, M. Roncarelli, D. Rosario, M. Rossetti, A. Rozanska, E. Rovilos, R. Salvaterra, M. Salvato, T. Di Salvo, J. Sanders, J. Sanz-Forcada, K. Schawinski, J. Schaye, A. Schwope, S. Sciortino, P. Severgnini, F. Shankar, D. Sijacki, S. Sim, C. Schmid, R. Smith, A. Steiner, B. Stelzer, G. Stewart, T. Strohmayer, L. Strüder, M. Sun, Y. Takei, V. Tatischeff, A. Tiengo, F. Tombesi, G. Trinchieri, T.G. Tsuru, A. Ud-Doula, E. Ursino, L. Valencic, E. Vanzella, S. Vaughan, C. Vignali, J. Vink, F. Vito, M. Volonteri, D. Wang, N. Webb, R. Willingale, J. Wilms, M. Wise, D. Worrall, A. Young, L. Zampieri, J. In’t Zand, S. Zane, A. Zezas, Y. Zhang, I. Zhuravleva, The hot and energetic universe: a white paper presenting the science theme motivating the Athena+ mission. arXiv e-prints, arXiv:1306.2307, June 2013

    Google Scholar 

  123. P.L. Nolan, D.E. Gruber, J.L. Matteson, L.E. Peterson, R.E. Rothschild, J.P. Doty, A.M. Levine, W.H.G. Lewin, F.A. Primini, Rapid variability of 10-140 KeV X-rays from CYG X-1. Astrophys. J. 246, 494–501 (1981)

    Article  ADS  Google Scholar 

  124. M.A. Nowak, R.V. Wagoner, M.C. Begelman, D.E. Lehr, The 67 HZ feature in the black hole candidate GRS 1915+105 as a possible “Diskoseismic” mode. Astrophys. J. Lett. 477(2), L91–L94 (1997)

    Article  ADS  Google Scholar 

  125. M.A. Nowak, B.A. Vaughan, J. Wilms, J.B. Dove, M.C. Begelman, Rossi X-ray timing explorer observation of Cygnus X-1. II. Timing analysis. Astrophys. J. 510(2), 874–891 (1999)

    Article  ADS  Google Scholar 

  126. J.F. Olive, D. Barret, L. Boirin, J.E. Grindlay, J.H. Swank, A.P. Smale, RXTE observation of the X-ray burster 1E 1724-3045. I. Timing study of the persistent X-ray emission with the PCA. Astron. Astrophys. 333, 942–951 (1998)

    Google Scholar 

  127. P.M. O’Neill, E. Kuulkers, R.K. Sood, M. van der Klis, The X-ray fast-time variability of Sco X-2 (GX 349+2) with RXTE. Mon. Not. R. Astron. Soc. 336(1), 217–232 (2002)

    Article  ADS  Google Scholar 

  128. V. Osherovich, L. Titarchuk, Kilohertz quasi-periodic oscillations in neutron star binaries modeled as Keplerian oscillations in a rotating frame of reference. Astrophys. J. Lett. 522(2), L113–L116 (1999)

    Article  ADS  Google Scholar 

  129. D. Pandel, P. Kaaret, S. Corbel, Relativistic iron line emission from the neutron star low-mass X-ray binary 4U 1636-536. Astrophys. J. 688(2), 1288–1294 (2008)

    Article  ADS  Google Scholar 

  130. P. Peille, D. Barret, P. Uttley, The spectral-timing properties of upper and lower kHz QPOs. Astrophys. J. 811(2), 109 (2015)

    Google Scholar 

  131. F. Pintore, T. Di Salvo, E. Bozzo, A. Sanna, L. Burderi, A. D’Aì, A. Riggio, F. Scarano, R. Iaria, Study of the reflection spectrum of the accreting neutron star GX 3+1 using XMM-Newton and INTEGRAL. Mon. Not. R. Astron. Soc. 450(2), 2016–2024 (2015)

    Article  ADS  Google Scholar 

  132. S. Piraino, A. Santangelo, P. Kaaret, B. Mück, A. D’Aì, T. Di Salvo, R. Iaria, N. Robba, L. Burderi, E. Egron, A relativistic iron emission line from the neutron star low-mass X-ray binary GX 3+1. Astron. Astrophys. 542, L27 (2012)

    Article  ADS  Google Scholar 

  133. D. Psaltis, C. Norman, On the origin of quasi-periodic oscillations and broad-band noise in accreting neutron stars and black holes. arXiv e-prints, astro-ph/0001391, January 2000

    Google Scholar 

  134. R.C. Reis, A.C. Fabian, A.J. Young, Relativistically broadened iron line in the Suzaku observation of the neutron star X-ray binary 4U 1705-44. Mon. Not. R. Astron. Soc. 399(1), L1–L5 (2009)

    Article  ADS  Google Scholar 

  135. R.A. Remillard, D. Lin, ASM Team at MIT, NASA/GSFC, New X-ray Transient, XTE J1701-462. Astron. Telegram 696, 1 (2006)

    ADS  Google Scholar 

  136. R.A. Remillard, E.H. Morgan, J.E. McClintock, C.D. Bailyn, J.A. Orosz, RXTE observations of 0.1–300 HZ quasi-periodic oscillationsin the microquasar GRO J1655-40. Astrophys. J. 522(1), 397–412 (1999)

    Google Scholar 

  137. M. Revnivtsev, E. Churazov, M. Gilfanov, R. Sunyaev, New class of low frequency QPOs: signature of nuclear burning or accretion disk instabilities? Astron. Astrophys. 372, 138–144 (2001)

    Article  ADS  Google Scholar 

  138. E. M. Ribeiro, M. Méndez, G. Zhang, A. Sanna, Relation between the properties of the kilohertz quasi-periodic oscillations and spectral parameters in 4U 1636-53. Mon. Not. R. Astron. Soc. 471(1), 1208–1214 (2017)

    Article  ADS  Google Scholar 

  139. E.M. Ribeiro, M. Méndez, M.G.B. de Avellar, G. Zhang, K. Karpouzas, The amplitude of the kilohertz quasi-periodic oscillations in 4U 1636-53 in the frequency-energy space. Mon. Not. R. Astron. Soc. 489(4), 4980–4991 (2019)

    Article  ADS  Google Scholar 

  140. R.R. Ross, A.C. Fabian, The spectra of accretion discs in low-mass X-ray binaries. Mon. Not. R. Astron. Soc. 281, 637 (1996)

    Article  ADS  Google Scholar 

  141. R.R. Ross, A.C. Fabian, X-ray reflection in accreting stellar-mass black hole systems. Mon. Not. R. Astron. Soc. 381(4), 1697–1701 (2007)

    Article  ADS  Google Scholar 

  142. A. Sanna, M. Méndez, D. Altamirano, J. Homan, P. Casella, T. Belloni, D. Lin, M. van der Klis, R. Wijnands, The kilohertz quasi-periodic oscillations during the Z and atoll phases of the unique transient XTE J1701-462. Mon. Not. R. Astron. Soc. 408(1), 622–630 (2010)

    Article  ADS  Google Scholar 

  143. A. Sanna, M. Méndez, T. Belloni, D. Altamirano, The time derivative of the kilohertz quasi-periodic oscillations in 4U 1636-53. Mon. Not. R. Astron. Soc. 424(4), 2936–2942 (2012)

    Article  ADS  Google Scholar 

  144. A. Sanna, B. Hiemstra, M. Méndez, D. Altamirano, T. Belloni, M. Linares, Broad iron line in the fast spinning neutron-star system 4U 1636-53. Mon. Not. R. Astron. Soc. 432(2), 1144–1161 (2013)

    Article  ADS  Google Scholar 

  145. A. Sanna, M. Méndez, D. Altamirano, T. Belloni, B. Hiemstra, M. Linares, Broad iron emission line and kilohertz quasi-periodic oscillations in the neutron star system 4U 1636-53. Mon. Not. R. Astron. Soc. 440(4), 3275–3284 (2014)

    Article  ADS  Google Scholar 

  146. N. Shaposhnikov, L. Titarchuk, P. Laurent, Discovery of red-skewed K α iron line in Cyg X-2 with Suzaku. Astrophys. J. 699(2), 1223–1228 (2009)

    Article  ADS  Google Scholar 

  147. L. Stella, M. Vietri, Lense-thirring precession and quasi-periodic oscillations in low-mass X-ray binaries. Astrophys. J. Lett. 492(1), L59–L62 (1998)

    Article  ADS  Google Scholar 

  148. L. Stella, M. Vietri, S. Morsink, General relativistic effects in Qpos. Astrophys. Lett. Commun. 38, 57 (1999)

    ADS  Google Scholar 

  149. T.E. Strohmayer, Discovery of a 450 HZ quasi-periodic oscillation from the microquasar GRO J1655-40 with the Rossi X-ray timing explorer. Astrophys. J. Lett. 552(1), L49–L53 (2001)

    Article  ADS  Google Scholar 

  150. T. Strohmayer, W. Zhang, A. Smale, C. Day, J. Swank, L. Titarchuk, U. Lee, U 1728-34. IAU Circulars 6387, 2 (1996)

    ADS  Google Scholar 

  151. T. Strohmayer, W. Zhang, J. Swank, U 1728-34. IAU Circulars 6320, 1 (1996)

    ADS  Google Scholar 

  152. T.E. Strohmayer, W. Zhang, J.H. Swank, A. Smale, L. Titarchuk, C. Day, U. Lee, Millisecond X-ray variability from an accreting neutron star system. Astrophys. J. Lett. 469, L9 (1996)

    Article  ADS  Google Scholar 

  153. R.A. Sunyaev, L.G. Titarchuk, Comptonization of X-rays in plasma clouds. Typical radiation spectra. Astron. Astrophys. 500, 167–184 (1980)

    Google Scholar 

  154. T.M. Tauris, E.P.J. Van Den Heuvel, Formation and Evolution of Compact Stellar X-ray Sources (Cambridge University Press, Cambridge, 2010), p. 623

    Google Scholar 

  155. Jr. Terrell, N. James, Shot-noise character of Cygnus X-1 pulsations. Astrophys. J. Lett. 174, L35 (1972)

    Google Scholar 

  156. J.S. Troyer, E.M. Cackett, Spectral-timing analysis of the lower kHz QPO in the low-mass X-ray binary Aquila X-1. Astrophys. J. 834(2), 131 (2017)

    Google Scholar 

  157. J.S. Troyer, E.M. Cackett, P. Peille, D. Barret, A systematic spectral-timing analysis of kilohertz quasi-periodic oscillations in the Rossi X-ray timing explorer archive. Astrophys. J. 860(2), 167 (2018)

    Google Scholar 

  158. P. Uttley, I.M. McHardy, The flux-dependent amplitude of broadband noise variability in X-ray binaries and active galaxies. Mon. Not. R. Astron. Soc. 323(2), L26–L30 (2001)

    Article  ADS  Google Scholar 

  159. P. Uttley, I.M. McHardy, S. Vaughan, Non-linear X-ray variability in X-ray binaries and active galaxies. Mon. Not. R. Astron. Soc. 359(1), 345–362 (2005)

    Article  ADS  Google Scholar 

  160. P. Uttley, T. Wilkinson, P. Cassatella, J. Wilms, K. Pottschmidt, M. Hanke, M. Böck, The causal connection between disc and power-law variability in hard state black hole X-ray binaries. Mon. Not. R. Astron. Soc. 414(1), L60–L64 (2011)

    Article  ADS  Google Scholar 

  161. M. van der Klis, Fourier techniques in X-ray timing, in NATO Advanced Science Institutes (ASI) Series C, vol. 262, ed. by H. Ögelman, E.P.J. van den Heuvel. NATO Advanced Science Institutes (ASI) Series C (1989), p. 27

    Google Scholar 

  162. M. van der Klis, F. Jansen, J. van Paradijs, W.H.G. Lewin, E.P.J. van den Heuvel, J.E. Trumper, M. Szatjno, Intensity-dependent quasi-periodic oscillations in the X-ray flux of GX5-1. Nature 316(6025), 225–230 (1985)

    Article  ADS  Google Scholar 

  163. M. van der Klis, J. Swank, W. Zhang, K. Jahoda, E. Morgan, W. Lewin, B. Vaughan, J. van Paradijs, Scorpius X-1. IAU Circulars 6319, 1 (1996)

    ADS  Google Scholar 

  164. M. van der Klis, J.H. Swank, W. Zhang, K. Jahoda, E.H. Morgan, W.H.G. Lewin, B. Vaughan, J. van Paradijs, Discovery of submillisecond quasi-periodic oscillations in the X-ray flux of Scorpius X-1. Astrophys. J. Lett. 469, L1 (1996)

    Article  ADS  Google Scholar 

  165. M. van der Klis, R.A.D. Wijnands, K. Horne, W. Chen, Kilohertz quasi-periodic oscillation peak separation is not constant in Scorpius X-1. Astrophys. J. Lett. 481(2), L97–L100 (1997)

    Article  ADS  Google Scholar 

  166. M. van Doesburgh, M. van der Klis, Testing the relativistic precession model using low-frequency and kHz quasi-periodic oscillations in neutron star low-mass X-ray binaries with known spin. Mon. Not. R. Astron. Soc. 465(3), 3581–3606 (2017)

    Article  ADS  Google Scholar 

  167. M. van Doesburgh, M. van der Klis, On the frequency correlations of low-frequency QPOs with kilohertz QPOs in accreting millisecond X-ray pulsars. Mon. Not. R. Astron. Soc. 490(4), 5270–5284 (2019)

    Article  ADS  Google Scholar 

  168. M. van Doesburgh, M. van der Klis, S.M. Morsink, The highest frequency kHz QPOs in neutron star low-mass X-ray binaries. Mon. Not. R. Astron. Soc. 479(1), 426–434 (2018)

    Article  ADS  Google Scholar 

  169. S. van Straaten, E.C. Ford, M. van der Klis, M. Méndez, P. Kaaret, Relations between timing features and colors in the X-ray binary 4U 0614+09. Astrophys. J. 540(2), 1049–1061 (2000)

    Article  ADS  Google Scholar 

  170. S. van Straaten, M. van der Klis, T. di Salvo, T. Belloni, A multi-Lorentzian timing study of the Atoll sources 4U 0614+09 and 4U 1728-34. Astrophys. J. 568(2), 912–930 (2002)

    Article  ADS  Google Scholar 

  171. S. van Straaten, M. van der Klis, M. Méndez, The Atoll source states of 4U 1608-52. Astrophys. J. 596(2), 1155–1176 (2003)

    ADS  Google Scholar 

  172. S. van Straaten, M. van der Klis, R. Wijnands, Relations between timing features and colors in accreting millisecond pulsars. Astrophys. J. 619(1), 455–482 (2005)

    Article  ADS  Google Scholar 

  173. B.A. Vaughan, M.A. Nowak, X-ray variability coherence: how to compute it, what it means, and how it constrains models of GX 339-4 and Cygnus X-1. Astrophys. J. Lett. 474(1), L43–L46 (1997)

    Article  ADS  Google Scholar 

  174. B.A. Vaughan, M. van der Klis, M. Méndez, J. van Paradijs, R.A.D. Wijnands, W.H.G. Lewin, F.K. Lamb, D. Psaltis, E. Kuulkers, T. Oosterbroek, Discovery of microsecond time lags in kilohertz QPOs. Astrophys. J. Lett. 483(2), L115–L118 (1997)

    Article  ADS  Google Scholar 

  175. B.A. Vaughan, M. van der Klis, M. Méndez, J. van Paradijs, R.A.D. Wijnands, W.H.G. Lewin, F.K. Lamb, D. Psaltis, E. Kuulkers, T. Oosterbroek, Erratum: discovery of microsecond time lags in kilohertz QPOs. Astrophys. J. Lett. 509(2), L145 (1998)

    Google Scholar 

  176. R.V. Wagoner, Relativistic diskoseismology. Phys. Rep. 311, 259–269 (1999)

    Article  ADS  Google Scholar 

  177. Y. Wang, M. Méndez, A. Sanna, D. Altamirano, T.M. Belloni, The reflection spectrum of the low-mass X-ray binary 4U 1636-53. Mon. Not. R. Astron. Soc. 468(2), 2256–2264 (2017)

    Article  ADS  Google Scholar 

  178. Y. Wang, M. Méndez, D. Altamirano, G. Zhang, T.M. Belloni, E.M. Ribeiro, M. Linares, A. Sanna, S.E. Motta, J.A. Tomsick, Study of the X-ray properties of the neutron star binary 4U 1728-34 from the soft-to-hard state. Mon. Not. R. Astron. Soc. 484(3), 3004–3016 (2019)

    Article  ADS  Google Scholar 

  179. A.L. Watts, Thermonuclear burst oscillations. Annu. Rev. Astron. Astrophys. 50, 609–640 (2012)

    Article  ADS  Google Scholar 

  180. A.L. Watts, W.F. Yu, J. Poutanen, S. Zhang, S. Bhattacharyya, S. Bogdanov, L. Ji, A. Patruno, T.E. Riley, P. Bakala, A. Baykal, F. Bernardini, I. Bombaci, E. Brown, Y. Cavecchi, D. Chakrabarty, J. Chenevez, N. Degenaar, M. Del Santo, T. Di Salvo, V. Doroshenko, M. Falanga, R.D. Ferdman, M. Feroci, A.F. Gambino, M.Y. Ge, S.K. Greif, S. Guillot, C. Gungor, D.H. Hartmann, K. Hebeler, A. Heger, J. Homan, R. Iaria, J. in’t. Zand, O. Kargaltsev, A. Kurkela, X.Y. Lai, A. Li, X.D. Li, Z.S. Li, M. Linares, F.J. Lu, S. Mahmoodifar, M. Méndez, M. Coleman Miller, S. Morsink, J. Nättilä, A. Possenti, C. Prescod-Weinstein, J.L. Qu, A. Riggio, T. Salmi, A. Sanna, A. Santangelo, H. Schatz, A. Schwenk, L.M. Song, E. Šrámková, B. Stappers, H. Stiele, T. Strohmayer, I. Tews, L. Tolos, G. Török, D. Tsang, M. Urbanec, A. Vacchi, R.X. Xu, Y.P. Xu, S. Zane, G.B. Zhang, S.N. Zhang, W.D. Zhang, S.J. Zheng, X. Zhou, Dense matter with eXTP. Sci. China Phys. Mech. Astron. 62(2), 29503 (2019)

    Google Scholar 

  181. N.E. White, L. Stella, A.N. Parmar, The X-ray spectral properties of accretion disks in X-ray binaries. Astrophys. J. 324, 363 (1988)

    Article  ADS  Google Scholar 

  182. R.A.D. Wijnands, M. van der Klis, Discovery of two simultaneous kilohertz quasi-periodic oscillations in KS 1731-260. Astrophys. J. Lett. 482(1), L65–L68 (1997)

    Article  ADS  Google Scholar 

  183. R.A.D. Wijnands, M. van der Klis, J. van Paradijs, W.H.G. Lewin, F.K. Lamb, B. Vaughan, E. Kuulkers, Discovery in 4U 1636-53 of two simultaneous quasi-periodic oscillations near 900 HZ and 1176 HZ. Astrophys. J. Lett. 479(2), L141–L144 (1997)

    Article  ADS  Google Scholar 

  184. R. Wijnands, J. Homan, M. van der Klis, E. Kuulkers, J. van Paradijs, W.H.G. Lewin, F.K. Lamb, D. Psaltis, B. Vaughan, Discovery of kHz quasi-periodic oscillations in the Z source Cygnus X-2. Astrophys. J. Lett. 493(2), L87–L90 (1998)

    Article  ADS  Google Scholar 

  185. W. Yu, M. van der Klis, Kilohertz quasi-periodic oscillation frequency anticorrelated with millihertz quasi-periodic oscillation flux in 4U 1608-52. Astrophys. J. Lett. 567(1), L67–L70 (2002)

    Article  ADS  Google Scholar 

  186. W. Yu, M. van der Klis, P.G. Jonker, Dependence of kilohertz quasi-periodic oscillation properties on the normal-branch oscillation phase in Scorpius X-1. Astrophys. J. Lett. 559(1), L29–L32 (2001)

    Article  ADS  Google Scholar 

  187. W. Zhang, T.E. Strohmayer, J.H. Swank, Discovery of two simultaneous kilohertz quasi-periodic oscillations in the persistent flux of GX 349+2. Astrophys. J. Lett. 500(2), L167–L169 (1998)

    Article  ADS  Google Scholar 

  188. G. Zhang, M. Méndez, A. Sanna, E.M. Ribeiro, J.D. Gelfand, Relation between spectral changes and the presence of the lower kHz QPO in the neutron star low-mass X-ray binary 4U 1636-53. Mon. Not. R. Astron. Soc. 465(4), 5003–5010 (2017)

    Article  ADS  Google Scholar 

  189. A. Zoghbi, P. Uttley, A.C. Fabian, Understanding reverberation lags in 1H0707-495. Mon. Not. R. Astron. Soc. 412(1), 59–64 (2011)

    Article  ADS  Google Scholar 

  190. A. Zoghbi, A.C. Fabian, C.S. Reynolds, E.M. Cackett, Relativistic iron K X-ray reverberation in NGC 4151. Mon. Not. R. Astron. Soc. 422(1), 129–134 (2012)

    Article  ADS  Google Scholar 

Download references

Acknowledgements

This work is part of the research programme Athena with project number 184.034.002, which is (partly) financed by the Dutch Research Council (NWO). TMB acknowledges financial contribution from the agreement ASI-INAF n.2017-14-H.0. This research has made use of data and/or software provided by the High Energy Astrophysics Science Archive Research Center (HEASARC), which is a service of the Astrophysics Science Division at NASA/GSFC. This research made use of NASA’s Astrophysics Data System.

Author information

Authors and Affiliations

  1. Kapteyn Astronomical Institute, University of Groningen, Groningen, The Netherlands

    Mariano Méndez

  2. INAF - Osservatorio Astronomico di Brera, Merate, Italy

    Tomaso M. Belloni

Authors
  1. Mariano Méndez
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Tomaso M. Belloni
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Tomaso M. Belloni .

Editor information

Editors and Affiliations

  1. INAF Osservatorio Astronomico di Brera, Merate, Italy

    Tomaso M. Belloni

  2. Kapteyn Astronomical Institute, University of Groningen, Groningen, The Netherlands

    Mariano Méndez

  3. National Astronomical Observatories and The University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, China

    Chengmin Zhang

Rights and permissions

Reprints and permissions

Copyright information

© 2021 Springer-Verlag GmbH Germany, part of Springer Nature

About this chapter

Check for updates. Verify currency and authenticity via CrossMark

Cite this chapter

Méndez, M., Belloni, T.M. (2021). High-Frequency Variability in Neutron-Star Low-Mass X-ray Binaries. In: Belloni, T.M., Méndez, M., Zhang, C. (eds) Timing Neutron Stars: Pulsations, Oscillations and Explosions. Astrophysics and Space Science Library, vol 461. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-662-62110-3_6

Download citation

  • DOI: https://doi.org/10.1007/978-3-662-62110-3_6

  • Published:

  • Publisher Name: Springer, Berlin, Heidelberg

  • Print ISBN: 978-3-662-62108-0

  • Online ISBN: 978-3-662-62110-3

  • eBook Packages: Physics and AstronomyPhysics and Astronomy (R0)

Publish with us

Policies and ethics

Search

Navigation