Article
Astronomy & Astrophysics
Jiachen Jiang, Douglas J. K. Buisson, Thomas Dauser, Andrew C. Fabian, Felix Furst, Luigi C. Gallo, Fiona A. Harrison, Michael L. Parker, James F. Steiner, John A. Tomsick, Santiago Ubach, Dominic J. Walton
Summary: In this study, the NuSTAR and Swift spectra of the black hole candidate MAXI J1813-095 in a failed-transition outburst in 2018 were analyzed. The analysis revealed evidence of reflected emission from the inner region of the accretion disc and provided insights into the inner radius of the disc. The spectral variability of MAXI J1813-095 was found to be dominated by the variable photon index of the Comptonization emission.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Zi-Xu Yang, Liang Zhang, S. N. Zhang, M. Mendez, Federico Garcia, Yue Huang, Qingcui Bu, He-Xin Liu, Wei Yu, P. J. Wang, L. Tao, D. Altamirano, Jin-Lu Qu, S. Zhang, X. Ma, L. M. Song, S. M. Jia, M. Y. Ge, Q. Z. Liu, J. Z. Yan, T. M. Li, X. Q. Ren, R. C. Ma, Yuexin Zhang, Y. C. Xu, B. Y. Ma, Y. F. Du, Y. C. Fu, Y. X. Xiao, P. P. Li, P. Jin, S. J. Zhao, Q. C. Zhao
Summary: In this paper, we present a broad-band spectral-timing analysis of fast transitions observed in the black hole X-ray binary GX 339-4. The transitions include shifts between band-limited noise-dominated power density spectra and type-B quasi-periodic oscillations, accompanied by rapid appearance or disappearance. Comparative studies with other sources, MAXI J1820+070 and MAXI J1348-630, reveal variations in spectral ratios above and below 10 keV, indicating an association between the appearance of type-B quasi-periodic oscillations and a redistribution of accretion power. The spectral ratios between periods with and without type-B quasi-periodic oscillations differ significantly from ratios between periods with type-B quasi-periodic oscillations and broad-band noise.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Nan Jia, Ye Feng, Yu-Jia Song, Jun Yang, Jieun Yuh, Pei-Jun Huang, Li-Jun Gou
Summary: We studied the spectral properties of the Galactic black hole candidate MAXI J0637-430 using NuSTAR and Swift/XRT data. By fitting the spectra with a disk component and a powerlaw component model, we found a black hole spin a* > 0.72 and an inclination angle i = 46.1(-5.34)(+4.0) degrees for the accretion disk. The fitting results also suggest an extreme supersolar iron abundance, possibly due to a high-density accretion disk or a strong Fe K alpha emission line. Additionally, a soft excess was observed in the soft state spectral fitting results, which may be caused by free-free heating effect from the high density of the accretion disk. The robustness of black hole spin obtained by X-ray reflection spectroscopy was discussed, showing that the spin results are independent of iron abundance and disk density.
RESEARCH IN ASTRONOMY AND ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Liang Zhang, Mariano Mendez, Federico Garcia, Yuexin Zhang, Ruican Ma, Diego Altamirano, Zi-Xu Yang, Xiang Ma, Lian Tao, Yue Huang, Shumei Jia, Shuang-Nan Zhang, Jinlu Qu, Liming Song, Shu Zhang
Summary: We present a detailed analysis of the spectral and timing characteristics of a 7-Hz type-A quasi-periodic oscillation (QPO) observed in the black hole X-ray binary MAXI J1348-630 during its high-soft state. The QPO exhibits similar spectral properties as the Comptonized component, suggesting that the variability is driven by the Comptonized region. The phase lags at the QPO frequency are always soft, indicating a softening effect at lower energies. The radiative properties of the type-A QPO can be explained by a vertically extended Comptonized region with a size of about 2300km.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Andrew Mummery
Summary: This paper discusses the "theory of propagating fluctuations" in the aperiodic variability observed in accreting black hole X-ray binary systems. It derives the Fourier transforms of the Green's function solutions of the thin disc equations and finds solutions for both Newtonian discs and general relativistic solutions with a vanishing ISCO stress. The study highlights the spin dependence of observable variability properties of black hole discs and suggests that observations of aperiodic variability may provide a new way to directly constrain black hole spins.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
F. M. Vincentelli, P. Casella, D. M. Russell, M. C. Baglio, A. Veledina, T. Maccarone, J. Malzac, R. Fender, K. O'Brien, P. Uttley
Summary: This study presents the results of the fast X-ray/infrared variability analysis of the black hole transient MAXI J1535-571, showing a strong asymmetric anticorrelation between X-ray and near-IR light curves. The detection of a near-IR QPO and simultaneous X-ray QPO at approximately the same frequency suggests a possible misalignment between the disc and jet in scenarios for fast IR variability.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Tenyo Kawamura, Chris Done, Magnus Axelsson, Tadayuki Takahashi
Summary: Black hole X-ray binaries exhibit stochastic variability on short time scales, with complex lags in correlated variability observed across different energy bands. This is usually explained by a model where slow fluctuations originating at large radii propagate through the accretion flow, modulating faster fluctuations generated at smaller radii. By incorporating radially stratified emission, it becomes possible to measure the propagation time scale from data, enabling direct tests of the accretion flow structure. However, when applying a previously developed model to higher energy variability data from the Insight-Hard X-ray Modulation Telescope (HXMT), it fails to accurately fit the observed behavior.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
B. De Marco, A. A. Zdziarski, G. Ponti, G. Migliori, T. M. Belloni, A. Segovia Otero, M. A. Dzielak, E. Lai
Summary: The study systematically examines the X-ray spectral-timing of the black hole X-ray binary system MAXI J1820+070, focusing on its outburst evolution. It finds that the frequency of thermal reverberation lags steadily increases throughout most of the outburst, indicating a decrease in the relative distance between the X-ray source and the disc as the source softens.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
Roberto Soria, Ruican Ma, Lian Tao, Shuang-Nan Zhang
Summary: By revisiting the published results of X-ray and optical studies on the black hole candidate MAXI J0637-430, we have improved the understanding of its system parameters. This black hole is the farthest known from the Galactic Center and has the shortest period among all Galactic black hole X-ray binaries.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Gitika Mall, Jithesh Vadakkumthani, Ranjeev Misra
Summary: We analyze the broadband X-ray spectrum of the black hole X-ray binary MAXI J1348--630 using five AstroSat observations. The source was observed in both the soft spectral state and the hard spectral state. In the soft state, the spectrum was modeled using a relativistic thin accretion disk with reflection features and thermal Comptonization, while in the hard state, the same model was used with a different assumption for the inner disk radius. The results suggest smaller truncation radii and lower accretion rates in the hard state compared to the soft state. The combined analysis with earlier temporal studies provides a comprehensive understanding of the source evolution.
RESEARCH IN ASTRONOMY AND ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
G. Panizo-Espinar, M. Armas Padilla, T. Munoz-Darias, K. I. I. Koljonen, V. A. Cuneo, J. Sanchez-Sierras, D. Mata Sanchez, J. Casares, J. Corral-Santana, R. P. Fender, F. Jimenez-Ibarra, G. Ponti, D. Steeghs, M. A. P. Torres
Summary: This study presents spectroscopic observations of the low mass X-ray binary, MAXI J1348-630, during its bright outburst. The authors found evidence of a cold accretion disc wind in the system, which was similar to those seen in other X-ray transients.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Geethu Prabhakar, Samir Mandal, M. P. Athulya, Anuj Nandi
Summary: This study presents a comprehensive analysis of the spectral and temporal properties of the black hole X-ray transient MAXI J1820+070 during its outbursts in 2018. The study reveals softening of the spectrum during the first outburst and dominance of thermal disc emission during the second outburst. The source exhibits strong reflection signatures and quasi-periodic oscillations throughout the entire outburst.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
J. Guan, L. Tao, J. L. Qu, S. N. Zhang, W. Zhang, S. Zhang, R. C. Ma, M. Y. Ge, L. M. Song, F. J. Lu, T. P. Li, Y. P. Xu, Y. Chen, X. L. Cao, C. Z. Liu, L. Zhang, Y. N. Wang, Y. P. Chen, Q. C. Bu, C. Cai, Z. Chang, L. Chen, T. X. Chen, Y. B. Chen, W. W. Cui, Y. Y. Du, G. H. Gao, H. Gao, Y. D. Gu, C. C. Guo, D. W. Han, Y. Huang, J. Huo, S. M. Jia, W. C. Jiang, J. Jin, L. D. Kong, B. Li, C. K. Li, G. Li, W. Li, X. Li, X. B. Li, X. F. Li, Z. W. Li, X. H. Liang, J. Y. Liao, B. S. Liu, H. W. Liu, H. X. Liu, X. J. Liu, X. F. Lu, Q. Luo, T. Luo, X. Ma, B. Meng, Y. Nang, J. Y. Nie, G. Ou, X. Q. Ren, N. Sai, X. Y. Song, L. Sun, Y. Tan, C. Wang, L. J. Wang, P. J. Wang, W. S. Wang, Y. S. Wang, X. Y. Wen, B. B. Wu, B. Y. Wu, M. Wu, G. C. Xiao, S. Xiao, S. L. Xiong, R. J. Yang, S. Yang, Y. J. Yang, Q. B. Yi, Q. Q. Yin, Y. You, F. Zhang, H. M. Zhang, J. Zhang, P. Zhang, W. C. Zhang, Y. F. Zhang, Y. H. Zhang, H. S. Zhao, X. F. Zhao, S. J. Zheng, Y. G. Zheng, D. K. Zhou
Summary: The Insight-HXMT observations of the black hole X-ray binary MAXI J1820+070 during its 2018 outburst show an evolution of the inferred spin and other parameters during its high soft state, possibly related to the evolution of the inner disc or deceleration of a jet-like corona. The spin of MAXI J1820+070 is constrained to be a(*) = 0.2(-0.3)(+0.2), indicating that the strong jet activity is mainly driven by the accretion disc rather than by the black hole spin.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
D. Mata Sanchez, A. Rau, A. Alvarez Hernandez, T. F. J. van Grunsven, M. A. P. Torres, P. G. Jonker
Summary: MAXI J1305-704 is proposed as a high-inclination candidate black hole X-ray binary based on its X-ray properties and behavior during outburst. Observations during quiescence reveal features consistent with a black hole nature, with estimated mass function confirming this. Estimates of distance and space velocity place the system in the Galactic thick disc, supporting significant natal kick formation if a supernova occurred in the Galactic Plane.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Federico Garcia, Mariano Mendez, Konstantinos Karpouzas, Tomaso Belloni, Liang Zhang, Diego Altamirano
Summary: Spectral-timing analysis of X-ray variability in black hole binaries is a powerful tool to study accretion/ejection flows. Type-B QPOs in the soft-intermediate state are linked to emission from relativistic jets. By studying the spectral-timing properties of MAXI J1348-630, a variable-Comptonization model successfully explains the radiative properties of the QPO.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
A. C. Fabian, C. S. Reynolds, J. Jiang, C. Pinto, L. C. Gallo, M. L. Parker, A. N. Lasenby, W. N. Alston, D. J. K. Buisson, E. M. Cackett, B. De Marco, J. Garcia, E. Kara, P. Kosec, M. J. Middleton, J. M. Miller, G. Miniutti, D. J. Walton, D. R. Wilkins, A. J. Young
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2020)
Article
Astronomy & Astrophysics
A. C. Fabian, D. J. Buisson, P. Kosec, C. S. Reynolds, D. R. Wilkins, J. A. Tomsick, D. J. Walton, P. Gandhi, D. Altamirano, Z. Arzoumanian, E. M. Cackett, S. Dyda, J. A. Garcia, K. C. Gendreau, B. W. Grefenstette, J. Homan, E. Kara, R. M. Ludlam, J. M. Miller, J. F. Steiner
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2020)
Article
Astronomy & Astrophysics
D. J. Walton, W. N. Alston, P. Kosec, A. C. Fabian, L. C. Gallo, J. A. Garcia, J. M. Miller, E. Nardini, M. T. Reynolds, C. Ricci, D. Stern, T. Dauser, F. A. Harrison, C. S. Reynolds
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2020)
Article
Astronomy & Astrophysics
D. J. K. Buisson, D. Altamirano, P. Bult, G. C. Mancuso, T. Guver, G. K. Jaisawal, J. Hare, A. C. Albayati, Z. Arzoumanian, N. Castro Segura, D. Chakrabarty, P. Gandhi, S. Guillot, J. Homan, K. C. Gendreau, J. Jiang, C. Malacaria, J. M. Miller, M. Ozbey Arabaci, R. Remillard, T. E. Strohmayer, F. Tombesi, J. A. Tomsick, F. M. Vincentelli, D. J. Walton
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2020)
Article
Astronomy & Astrophysics
B. E. Tetarenko, A. W. Shaw, E. R. Manrow, P. A. Charles, J. M. Miller, T. D. Russell, A. J. Tetarenko
Summary: This study presents an 8-month long multiwavelength monitoring campaign of the new candidate black hole LMXB MAXI J0637-430, along with three quasi-simultaneous epochs of Gemini/GMOS optical spectroscopy. Evidence is found for a correlation between the X-ray irradiation heating the accretion disc and the evolution of the Heii 4686 angstrom emission line profiles detected in the optical spectra. The results demonstrate a connection between the line emitting regions and physical properties of the X-ray irradiation heating the discs during outburst cycles of LMXBs.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
A. S. Parikh, N. Degenaar, J. V. Hernandez Santisteban, R. Wijnands, I Psaradaki, E. Costantini, D. Modiano, J. M. Miller
Summary: Researchers studying the ultraviolet and X-ray data of EXO 0748-676 during quiescence have found that the UV and X-ray emissions of this source may have different origins, with thermal emission from the neutron star's crust-cooling possibly dominating the observed X-ray flux evolution.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
M. Balakrishnan, J. M. Miller, M. T. Reynolds, E. Kammoun, A. Zoghbi, B. E. Tetarenko
Summary: GRS 1915+105 is a stellar-mass black hole known for its diverse X-ray variability, which entered a new accretion state in early 2019, resulting in a significant decrease in flux. The new state is characterized by internal obscuration and reduced mass accretion rate, with implications for black holes across different mass scales.
ASTROPHYSICAL JOURNAL
(2021)
Article
Astronomy & Astrophysics
A. Zoghbi, J. M. Miller, E. Cackett
Summary: X-ray reverberation mapping is a new tool to study accretion in AGN, but recent observations of Seyfert Galaxies show that the data does not match predictions from the relativistic reverberation model.
ASTROPHYSICAL JOURNAL
(2021)
Article
Astronomy & Astrophysics
J. M. Miller, A. Zoghbi, M. T. Reynolds, J. Raymond, D. Barret, E. Behar, W. N. Brandt, L. Brenneman, P. Draghis, E. Kammoun, M. J. Koss, A. Lohfink, D. K. Stern
Summary: Research shows that accretion disks and coronae around massive black holes may decouple in the short term. Observations of Mrk 817 reveal that the X-ray and UV spectra are decoupled on timescales of weeks and months, potentially requiring the presence of a mechanical beaming of the innermost accretion flow or an absorber to explain.
ASTROPHYSICAL JOURNAL LETTERS
(2021)
Article
Astronomy & Astrophysics
Luigi C. Gallo, Adam G. Gonzalez, Jon M. Miller
Summary: The study reports a rapid occultation event in the Seyfert galaxy NGC 6814, revealing the properties and location of the obscuring gas through spectral and timing analyses, which can be utilized to measure the active region surrounding the event horizon.
ASTROPHYSICAL JOURNAL LETTERS
(2021)
Article
Astronomy & Astrophysics
J. M. Miller, A. Zoghbi, J. Raymond, M. Balakrishnan, L. Brenneman, E. Cackett, P. Draghis, A. C. Fabian, E. Gallo, J. Kaastra, T. Kallman, E. Kammoun, S. E. Motta, D. Proga, M. T. Reynolds, N. Trueba
ASTROPHYSICAL JOURNAL
(2020)
Article
Astronomy & Astrophysics
E. S. Kammoun, J. M. Miller, M. Koss, K. Oh, A. Zoghbi, R. F. Mushotzky, D. Barret, E. Behar, W. N. Brandt, L. W. Brenneman, J. S. Kaastra, A. M. Lohfink, D. Proga, D. Stern
ASTROPHYSICAL JOURNAL
(2020)
Article
Astronomy & Astrophysics
Paul A. Draghis, Jon M. Miller, Edward M. Cackett, Elias S. Kammoun, Mark T. Reynolds, John A. Tomsick, Abderahmen Zoghbi
ASTROPHYSICAL JOURNAL
(2020)
Article
Astronomy & Astrophysics
Nicolas Trueba, J. M. Miller, A. C. Fabian, J. Kaastra, T. Kallman, A. Lohfink, D. Proga, J. Raymond, C. Reynolds, M. Reynolds, A. Zoghbi
ASTROPHYSICAL JOURNAL LETTERS
(2020)
Article
Astronomy & Astrophysics
R. M. Ludlam, E. M. Cackett, J. A. Garcia, J. M. Miller, P. M. Bult, T. E. Strohmayer, S. Guillot, G. K. Jaisawal, C. Malacaria, A. C. Fabian, C. B. Markwardt
ASTROPHYSICAL JOURNAL
(2020)