T. M. Belloni - INAF-OAB

T. M. Belloni
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T. M. Belloni
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High Energy Astrophysical Phenomena (49)
 
Astrophysics of Galaxies (2)
 
Cosmology and Nongalactic Astrophysics (2)
 
Instrumentation and Methods for Astrophysics (2)
 
Solar and Stellar Astrophysics (2)

Publications Authored By T. M. Belloni

We performed an analysis of all RXTE observations of the Low Mass X-ray Binary and Black Hole Candidate IGR J17091-3624 during the 2011-2013 outburst of the source. By creating lightcurves, hardness-intensity diagrams and power density spectra of each observation, we have created a set of 9 variability `classes' that phenomenologically describe the range of types of variability seen in this object. We compare our set of variability classes to those established by Belloni et al. Read More

We present 3-79 keV NuSTAR observations of the neutron star low-mass X-ray binary 4U 1636-53 in the soft, transitional and hard state. The spectra display a broad emission line at 5-10 keV. We applied several models to fit this line: A GAUSSIAN line, a relativistically broadened emission line model, KYRLINE, and two models including relativistically smeared and ionized reflection off the accretion disc with different coronal heights, RELXILL and RELXILLLP. Read More

Black hole X-ray binaries undergo occasional outbursts caused by changing inner accretion flows. Here we report high-angular resolution radio observations of the 2013 outburst of the black hole candidate X-ray binary system J1908+094, using data from the VLBA and EVN. We show that following a hard-to-soft state transition, we detect moving jet knots that appear asymmetric in morphology and brightness, and expand to become laterally resolved as they move away from the core, along an axis aligned approximately $-11$\degree\ east of north. Read More

X-ray binary observations led to the interpretation that powerful compact jets, produced in the hard state, are quenched when the source transitions to its soft state. The aim of this paper is to discuss the possibility that a powerful dark jet is still present in the soft state. Using the black hole X-ray binaries GX339-4 and H1743-322 as test cases, we feed observed X-ray power density spectra in the soft state of these two sources to an internal shock jet model. Read More

Blazars are the most luminous and variable AGNs, and thus excellent probes of accretion and emission processes close to the central engine. We focus on PKS 1510-089 ($z=0.36$), one of the brightest gamma-ray sources in the Fermi LAT catalog, to study its complex multi-wavelength variability. Read More

In search for the counterpart to the Fermi-LAT source 3FGL J0838.8-2829, we report on 1) a new magnetic Cataclysmic Variable (mCV), RX J0838-2827, that we identify as an asynchronous system (therefore not associated with this Fermi-LAT source) and 2) on a new X-ray flaring source, XMM J083850.4-282759, that might be tentatively identified as new candidate Transitional Millisecond Pulsar, possibly associated with the gamma-ray source. Read More

Quasi-periodic oscillations (QPOs) with frequencies from $\sim0.05$-$30$ Hz are a common feature in the X-ray emission of accreting black hole binaries. As the QPOs originate from the innermost accretion flow, they provide the opportunity to probe the behaviour of matter in extreme gravity. Read More

2016Jul
Authors: S. N. Zhang, M. Feroci, A. Santangelo, Y. W. Dong, H. Feng, F. J. Lu, K. Nandra, Z. S. Wang, S. Zhang, E. Bozzo, S. Brandt, A. De Rosa, L. J. Gou, M. Hernanz, M. van der Klis, X. D. Li, Y. Liu, P. Orleanski, G. Pareschi, M. Pohl, J. Poutanen, J. L. Qu, S. Schanne, L. Stella, P. Uttley, A. Watts, R. X. Xu, W. F. Yu, J. J. M. in 't Zand, S. Zane, L. Alvarez, L. Amati, L. Baldini, C. Bambi, S. Basso, S. Bhattacharyya, R. Bellazzini, T. Belloni, P. Bellutti, S. Bianchi, A. Brez, M. Bursa, V. Burwitz, C. Budtz-Jorgensen, I. Caiazzo, R. Campana, X. L. Cao, P. Casella, C. Y. Chen, L. Chen, T. X. Chen, Y. Chen, Y. Chen, Y. P. Chen, M. Civitani, F. Coti Zelati, W. Cui, W. W. Cui, Z. G. Dai, E. Del Monte, D. De Martino, S. Di Cosimo, S. Diebold, M. Dovciak, I. Donnarumma, V. Doroshenko, P. Esposito, Y. Evangelista, Y. Favre, P. Friedrich, F. Fuschino, J. L. Galvez, Z. L. Gao, M. Y. Ge, O. Gevin, D. Goetz, D. W. Han, J. Heyl, J. Horak, W. Hu, F. Huang, Q. S. Huang, R. Hudec, D. Huppenkothen, G. L. Israel, A. Ingram, V. Karas, D. Karelin, P. A. Jenke, L. Ji, T. Kennedy, S. Korpela, D. Kunneriath, C. Labanti, G. Li, X. Li, Z. S. Li, E. W. Liang, O. Limousin, L. Lin, Z. X. Ling, H. B. Liu, H. W. Liu, Z. Liu, B. Lu, N. Lund, D. Lai, B. Luo, T. Luo, B. Ma, S. Mahmoodifar, M. Marisaldi, A. Martindale, N. Meidinger, Y. P. Men, M. Michalska, R. Mignani, M. Minuti, S. Motta, F. Muleri, J. Neilsen, M. Orlandini, A T. Pan, A. Patruno, E. Perinati, A. Picciotto, C. Piemonte, M. Pinchera, A. Rachevski, M. Rapisarda, N. Rea, E. M. R. Rossi, A. Rubini, G. Sala, X. W. Shu, C. Sgro, Z. X. Shen, P. Soffitta, L. M. Song, G. Spandre, G. Stratta, T. E. Strohmayer, L. Sun, J. Svoboda, G. Tagliaferri, C. Tenzer, H. Tong, R. Taverna, G. Torok, R. Turolla, A. Vacchi, J. Wang, J. X. Wang, D. Walton, K. Wang, J. F. Wang, R. J. Wang, Y. F. Wang, S. S. Weng, J. Wilms, B. Winter, X. Wu, X. F. Wu, S. L. Xiong, Y. P. Xu, Y. Q. Xue, Z. Yan, S. Yang, X. Yang, Y. J. Yang, F. Yuan, W. M. Yuan, Y. F. Yuan, G. Zampa, N. Zampa, A. Zdziarski, C. Zhang, C. L. Zhang, L. Zhang, X. Zhang, Z. Zhang, W. D. Zhang, S. J. Zheng, P. Zhou, X. L. Zhou

eXTP is a science mission designed to study the state of matter under extreme conditions of density, gravity and magnetism. Primary targets include isolated and binary neutron stars, strong magnetic field systems like magnetars, and stellar-mass and supermassive black holes. The mission carries a unique and unprecedented suite of state-of-the-art scientific instruments enabling for the first time ever the simultaneous spectral-timing-polarimetry studies of cosmic sources in the energy range from 0. Read More

The last two decades have seen a great improvement in our understand- ing of the complex phenomenology observed in transient black-hole binary systems, especially thanks to the activity of the Rossi X-Ray Timing Explorer satellite, com- plemented by observations from many other X-ray observatories and ground-based radio, optical and infrared facilities. Accretion alone cannot describe accurately the intricate behavior associated with black-hole transients and it is now clear that the role played by different kinds of (often massive) outflows seen at different phases of the outburst evolution of these systems is as fundamental as the one played by the accretion process itself. The spectral-timing states originally identified in the X-rays and fundamentally based on the observed effect of accretion, have acquired new importance as they now allow to describe within a coherent picture the phenomenology observed at other wave- length, where the effects of ejection processes are most evident. Read More

We studied time variability and spectral evolution of the Galactic black hole transient Swift J174510.8-262411 during the first phase of its outburst. INTEGRAL and Swift observations collected from 2012 September 16 until October 30 have been used. Read More

We present the pulsation and spectral characteristics of the HMXB 4U 0114+65 during a \emph{Suzaku} observation covering the part of the orbit that included the previously known low intensity emission of the source (dip) and the egress from this state. This dip has been interpreted in previous works as an X-ray eclipse. Notably, in this Suzaku observation, the count rate during and outside the dip vary by a factor of only 2-4 at odds with the eclipses of other HMXBs, where the intensity drops upto two orders of magnitude. Read More

We present an analysis of X-ray, Ultraviolet and optical/near-IR photometric data of the transitional millisecond pulsar binary XSSJ12270-4859, obtained at different epochs after the transition to a rotation-powered radio pulsar state. The observations, while confirming the large-amplitude orbital modulation found in previous studies after the state change, also reveal an energy dependence of the amplitudes as well as variations on time scale of months. The amplitude variations are anti-correlated in the X-ray and the UV/optical bands. Read More

2015Jun
Affiliations: 1ICRAR/Curtin, 2ICRAR/Curtin, 3Oxford, 4R. J. College, 5Oxford, 6U Southampton, 7USRA, 8Oxford, 9INAF-OAB, 10Oxford, 11Radboud U, 12Wheaton, 13API/UvA, 14XMM-NSOC, 15Cavendish Lab, 16NRC, 17NYU-AD, 18ICRAR/Curtin, 19U Virginia, 20U Alberta, 21ICRAR/Curtin, 22U Alberta, 23Cavendish Lab, 24ISS

XTE J1908+094 is an X-ray transient black hole candidate in the Galactic plane that was observed in outburst in 2002 and 2013. Here we present multi-frequency radio and X-ray data, including radio polarimetry, spanning the entire period of the 2013 outburst. We find that the X-ray behaviour of XTE J1908+094 traces the standard black hole hardness-intensity path, evolving from a hard state, through a soft state, before returning to a hard state and quiescence. Read More

2015Mar
Affiliations: 1ICRAR/Curtin University, 2ICRAR/Curtin University, 3ICRAR/Curtin University, 4ICRAR/Curtin University, 5U Southampton, 6AIM/CEA-Saclay, 7U Cape Town, 8NYU Abu Dhabi, 9NYU Abu Dhabi, 10U Alberta, 11ICRAR/Curtin University, 12INAF, 13Oxford University, 14U Wisconsin-Madison, 15SRON, 16NASA/GSFC, 17Radboud U, 18Wheaton College, 19U Amsterdam, 20Cambridge, 21U Barcelona, 22MIT, 23NRC, 24U Virginia, 25U Alberta, 26SRON, 27ISS, 28CSIRO

MAXI J1836-194 is a Galactic black hole candidate X-ray binary that was discovered in 2011 when it went into outburst. In this paper, we present the full radio monitoring of this system during its `failed' outburst, in which the source did not complete a full set of state changes, only transitioning as far as the hard intermediate state. Observations with the Karl G. Read More

This is a White Paper in support of the mission concept of the Large Observatory for X-ray Timing (LOFT), proposed as a medium-sized ESA mission. We discuss the potential of LOFT for the study of the physics of accretion and ejection around compact objects. For a summary, we refer to the paper. Read More

We studied the properties of the low-frequency quasi-periodic oscillations detected in a sample of six black hole candidates (XTE J1550-564, H 1743-322, XTE J1859+226, 4U 1630-47,GX 339-4, XTE J1650-500) observed by the Rossi XTE satellite. We analyzed the relation between the full width half maximum and the frequency of all the narrow peaks detected in power density spectra where a type-C QPO is observed. Our goal was to understand the nature of the modulation of the signal by comparing the properties of different harmonic peaks in the power density spectrum. Read More

Aims: We summarize the current observational picture of the outbursts of black-hole X-ray transients (BHTs), based on the evolution traced in a hardness-luminosity diagram (HLD), and we offer a physical interpretation. Methods: The basic ingredient in our interpretation is the Poynting-Robertson Cosmic Battery (PRCB, Contopoulos & Kazanas 1998), which provides locally the poloidal magnetic field needed for the ejection of the jet. In addition, we make two assumptions, easily justifiable. Read More

We present the first detection of X-ray coherent pulsations from the transitional millisecond pulsar XSS J12270-4859, while it was in a sub-luminous accretion disk state characterized by a 0.5-10 keV luminosity of 5E33 erg/s (assuming a distance of 1.4 kpc). Read More

We studied the horizontal branch oscillations (HBO) and the band-limited components observed in the power spectra of the transient neutron star low-mass X-ray binary XTE J1701-462 and the persistent "Sco-like" Z source GX 17+2. These two components were studied based on the state-resolved spectra. We found that the frequencies of XTE J1701-462 lie on the known correlations (WK and PBK), showing consistency with other types of X-ray binaries (black holes, atoll sources and millisecond X-ray pulsars). Read More

We study the temporal and energy spectral characteristics of the persistent black hole X-ray binary LMC X-1 using two XMM-Newton and a Suzaku observation. We report the discovery of low frequency (~ 26-29 mHz) quasi-periodic oscillations (QPOs). We also report the variablity of the broad iron K-alpha line studied earlier with Suzaku. Read More

IGR J17361-4441 was discovered by INTEGRAL undergoing its first detectable X-ray outburst in 2011 and initially classified as an accreting X-ray binary in the globular cluster NGC 6388. A reanalysis of the outburst data collected with INTEGRAL and Swift suggested that the enhanced X-ray emission from IGR J17361-4441 could have been due to a rare tidal disruption event of a terrestrial- icy planet by a white dwarf. In this letter we report on the analysis of XMM-Newton data collected in 2011 during the outburst from IGR J17361-4441. Read More

We characterized the broad-band X-ray spectra of Swift J1745-26 during the decay of the 2013 outburst using INTEGRAL ISGRI, JEM-X and Swift XRT. The X-ray evolution is compared to the evolution in optical and radio. We fit the X- ray spectra with phenomenological and Comptonization models. Read More

2014Aug
Authors: M. Feroci1, J. W. den Herder2, E. Bozzo3, D. Barret4, S. Brandt5, M. Hernanz6, M. van der Klis7, M. Pohl8, A. Santangelo9, L. Stella10, A. Watts11, J. Wilms12, S. Zane13, M. Ahangarianabhari14, C. Albertus15, M. Alford16, A. Alpar17, D. Altamirano18, L. Alvarez19, L. Amati20, C. Amoros21, N. Andersson22, A. Antonelli23, A. Argan24, R. Artigue25, B. Artigues26, J. -L. Atteia27, P. Azzarello28, P. Bakala29, G. Baldazzi30, S. Balman31, M. Barbera32, C. van Baren33, S. Bhattacharyya34, A. Baykal35, T. Belloni36, F. Bernardini37, G. Bertuccio38, S. Bianchi39, A. Bianchini40, P. Binko41, P. Blay42, F. Bocchino43, P. Bodin44, I. Bombaci45, J. -M. Bonnet Bidaud46, S. Boutloukos47, L. Bradley48, J. Braga49, E. Brown50, N. Bucciantini51, L. Burderi52, M. Burgay53, M. Bursa54, C. Budtz-Jørgensen55, E. Cackett56, F. R. Cadoux57, P. Cais58, G. A. Caliandro59, R. Campana60, S. Campana61, F. Capitanio62, J. Casares63, P. Casella64, A. J. Castro-Tirado65, E. Cavazzuti66, P. Cerda-Duran67, D. Chakrabarty68, F. Château69, J. Chenevez70, J. Coker71, R. Cole72, A. Collura73, R. Cornelisse74, T. Courvoisier75, A. Cros76, A. Cumming77, G. Cusumano78, A. D'Aì79, V. D'Elia80, E. Del Monte81, A. De Luca82, D. De Martino83, J. P. C. Dercksen84, M. De Pasquale85, A. De Rosa86, M. Del Santo87, S. Di Cosimo88, S. Diebold89, T. Di Salvo90, I. Donnarumma91, A. Drago92, M. Durant93, D. Emmanoulopoulos94, M. H. Erkut95, P. Esposito96, Y. Evangelista97, A. Fabian98, M. Falanga99, Y. Favre100, C. Feldman101, V. Ferrari102, C. Ferrigno103, M. Finger104, M. H. Finger105, G. W. Fraser106, M. Frericks107, F. Fuschino108, M. Gabler109, D. K. Galloway110, J. L. Galvez Sanchez111, E. Garcia-Berro112, B. Gendre113, S. Gezari114, A. B. Giles115, M. Gilfanov116, P. Giommi117, G. Giovannini118, M. Giroletti119, E. Gogus120, A. Goldwurm121, K. Goluchová122, D. Götz123, C. Gouiffes124, M. Grassi125, P. Groot126, M. Gschwender127, L. Gualtieri128, C. Guidorzi129, L. Guy130, D. Haas131, P. Haensel132, M. Hailey133, F. Hansen134, D. H. Hartmann135, C. A. Haswell136, K. Hebeler137, A. Heger138, W. Hermsen139, J. Homan140, A. Hornstrup141, R. Hudec142, J. Huovelin143, A. Ingram144, J. J. M. in't Zand145, G. Israel146, K. Iwasawa147, L. Izzo148, H. M. Jacobs149, F. Jetter150, T. Johannsen151, H. M. Jacobs152, P. Jonker153, J. Josè154, P. Kaaret155, G. Kanbach156, V. Karas157, D. Karelin158, D. Kataria159, L. Keek160, T. Kennedy161, D. Klochkov162, W. Kluzniak163, K. Kokkotas164, S. Korpela165, C. Kouveliotou166, I. Kreykenbohm167, L. M. Kuiper168, I. Kuvvetli169, C. Labanti170, D. Lai171, F. K. Lamb172, P. P. Laubert173, F. Lebrun174, D. Lin175, D. Linder176, G. Lodato177, F. Longo178, N. Lund179, T. J. Maccarone180, D. Macera181, S. Maestre182, S. Mahmoodifar183, D. Maier184, P. Malcovati185, I. Mandel186, V. Mangano187, A. Manousakis188, M. Marisaldi189, A. Markowitz190, A. Martindale191, G. Matt192, I. M. McHardy193, A. Melatos194, M. Mendez195, S. Mereghetti196, M. Michalska197, S. Migliari198, R. Mignani199, M. C. Miller200, J. M. Miller201, T. Mineo202, G. Miniutti203, S. Morsink204, C. Motch205, S. Motta206, M. Mouchet207, G. Mouret208, J. Mulačová209, F. Muleri210, T. Muñoz-Darias211, I. Negueruela212, J. Neilsen213, A. J. Norton214, M. Nowak215, P. O'Brien216, P. E. H. Olsen217, M. Orienti218, M. Orio219, M. Orlandini220, P. Orleanski221, J. P. Osborne222, R. Osten223, F. Ozel224, L. Pacciani225, M. Paolillo226, A. Papitto227, J. M. Paredes228, A. Patruno229, B. Paul230, E. Perinati231, A. Pellizzoni232, A. V. Penacchioni233, M. A. Perez234, V. Petracek235, C. Pittori236, J. Pons237, J. Portell238, A. Possenti239, J. Poutanen240, M. Prakash241, P. Le Provost242, D. Psaltis243, D. Rambaud244, P. Ramon245, G. Ramsay246, M. Rapisarda247, A. Rachevski248, I. Rashevskaya249, P. S. Ray250, N. Rea251, S. Reddy252, P. Reig253, M. Reina Aranda254, R. Remillard255, C. Reynolds256, L. Rezzolla257, M. Ribo258, R. de la Rie259, A. Riggio260, A. Rios261, P. Rodríguez- Gil262, J. Rodriguez263, R. Rohlfs264, P. Romano265, E. M. R. Rossi266, A. Rozanska267, A. Rousseau268, F. Ryde269, L. Sabau-Graziati270, G. Sala271, R. Salvaterra272, A. Sanna273, J. Sandberg274, S. Scaringi275, S. Schanne276, J. Schee277, C. Schmid278, S. Shore279, R. Schneider280, A. Schwenk281, A. D. Schwope282, J. -Y. Seyler283, A. Shearer284, A. Smith285, D. M. Smith286, P. J. Smith287, V. Sochora288, P. Soffitta289, P. Soleri290, A. Spencer291, B. Stappers292, A. W. Steiner293, N. Stergioulas294, G. Stratta295, T. E. Strohmayer296, Z. Stuchlik297, S. Suchy298, V. Sulemainov299, T. Takahashi300, F. Tamburini301, T. Tauris302, C. Tenzer303, L. Tolos304, F. Tombesi305, J. Tomsick306, G. Torok307, J. M. Torrejon308, D. F. Torres309, A. Tramacere310, A. Trois311, R. Turolla312, S. Turriziani313, P. Uter314, P. Uttley315, A. Vacchi316, P. Varniere317, S. Vaughan318, S. Vercellone319, V. Vrba320, D. Walton321, S. Watanabe322, R. Wawrzaszek323, N. Webb324, N. Weinberg325, H. Wende326, P. Wheatley327, R. Wijers328, R. Wijnands329, M. Wille330, C. A. Wilson-Hodge331, B. Winter332, K. Wood333, G. Zampa334, N. Zampa335, L. Zampieri336, L. Zdunik337, A. Zdziarski338, B. Zhang339, F. Zwart340, M. Ayre341, T. Boenke342, C. Corral van Damme343, E. Kuulkers344, D. Lumb345
Affiliations: 11,1b, 2SRON, The Netherlands, 3ISDC, Geneve University, Switzerland, 4IRAP, Toulouse, France, 5National Space Institute, Lyngby, Denmark, 6IEEC-CSIC-UPC-UB, Barcelona, Spain, 7Astronomical Institute Anton Pannekoek, University of Amsterdam, The Netherlands, 8DPNC, Geneve University, Switzerland, 9IAAT Tuebingen, Germany, 10INAF-OA Rome, Italy, 11Astronomical Institute Anton Pannekoek, University of Amsterdam, The Netherlands, 12University of Erlangen-Nuremberg, Germany, 13MSSL, Surrey, United Kingdom, 14Politecnico Milano, Italy, 15Universidad de Granada, Spain, 16Washington University, United States, 17Sabanci University, Istanbul, Turkey, 18Astronomical Institute Anton Pannekoek, University of Amsterdam, The Netherlands, 19IEEC-CSIC-UPC-UB, Barcelona, Spain, 20INAF-IASF-Bologna, Italy, 21IRAP, Toulouse, France, 22Faculty of Physical and Applied Sciences, University of Southampton, United Kingdom, 23ASDC, Rome, Italy, 24IAPS-INAF, Rome, Italy, 25IRAP, Toulouse, France, 26IEEC-CSIC-UPC-UB, Barcelona, Spain, 27IRAP, Toulouse, France, 28ISDC, Geneve University, Switzerland, 29Silesian University in Opava, Czech Republic, 30University of Bologna, Italy, 31Middle East Technical University, Ankara, Turkey, 32Dipartimento di Chimica e Fisica, Palermo University, Italy, 33SRON, The Netherlands, 34Tata Institute of Fundamental Research, Mumbai, India, 35Middle East Technical University, Ankara, Turkey, 36INAF-OA Brera, Italy, 37Wayne State University, Detroit, United States, 38Politecnico Milano, Italy, 39University of Rome III, Italy, 40Dept. of Physics and Astronomy University of Padua, Italy, 41ISDC, Geneve University, Switzerland, 42University of Valencia, Spain, 43INAF-OA Padova, Padova, Italy, 44CNES, Toulouse, France, 45University of Pisa, Italy, 46CEA Saclay, DSM/IRFU/SAp, France, 47IAAT Tuebingen, Germany, 48MSSL, Surrey, United Kingdom, 49INPE, São José dos Campos, Brazil, 50Michigan state University, United States, 51Arcetri Observatory, INAF, Firenze, Italy, 52Cagliari University, Italy, 53INAF-OA Cagliari, Italy, 54Astronomical Institute of the Academy of Sciences of the Czech Republic, Czech Republic, 55National Space Institute, Lyngby, Denmark, 56Wayne State University, Detroit, United States, 57DPNC, Geneve University, Switzerland, 58Laboratoire d'Astrophysique de Bordeaux, France, 59IEEC-CSIC-UPC-UB, Barcelona, Spain, 601,1b, 61INAF-OA Brera, Italy, 62IAPS-INAF, Rome, Italy, 63Instituto de Astrofisica de Canarias, Tenerife, Spain, 64INAF-OA Rome, Italy, 65Instituto Astrofisica de Andalucia, Granada, Spain, 66ASDC, Rome, Italy, 67University of Valencia, Spain, 68MIT, Cambridge, United States, 69CEA Saclay, DSM/IRFU/SAp, France, 70National Space Institute, Lyngby, Denmark, 71MSSL, Surrey, United Kingdom, 72MSSL, Surrey, United Kingdom, 73INAF- Osservatorio Astronomico di Palermo, Italy, 74Instituto de Astrofisica de Canarias, Tenerife, Spain, 75ISDC, Geneve University, Switzerland, 76IRAP, Toulouse, France, 77INAF-OA Capodimonte, Napoli, Italy, 78INAF IFC, Palermo, Italy, 79Dipartimento di Chimica e Fisica, Palermo University, Italy, 80ASDC, Rome, Italy, 811,1b, 82INAF-IASF-Milano, Italy, 83INAF-OA Capodimonte, Napoli, Italy, 84SRON, The Netherlands, 85MSSL, Surrey, United Kingdom, 86IAPS-INAF, Rome, Italy, 87IAPS-INAF, Rome, Italy, 88IAPS-INAF, Rome, Italy, 89IAAT Tuebingen, Germany, 90Dipartimento di Chimica e Fisica, Palermo University, Italy, 91IAPS-INAF, Rome, Italy, 92Ferrara University, Ferrara, Italy, 93Department of Medical Biophysics, University of Toronto, Canada, 94School of Physics and Astronomy, University of Southampton, United Kingdom, 95Istanbul Kültür University, Turkey, 96INAF-IASF-Milano, Italy, 971,1b, 98Cambridge University, Cambridge, United Kingdom, 99ISSI Bern, Switzerland, 100DPNC, Geneve University, Switzerland, 101Leicester University, United Kingdom, 102Sapienza University, Rome, Italy, 103ISDC, Geneve University, Switzerland, 104Charles University in Prague, Czech Republic, 105Universities Space Research Association, Huntsville, United States, 106Leicester University, United Kingdom, 107SRON, The Netherlands, 108INAF-IASF-Bologna, Italy, 109University of Valencia, Spain, 110Monash Centre for Astrophysics, School of Physics and School of Mathematical Sciences, Monash University, Australia, 111IEEC-CSIC-UPC-UB, Barcelona, Spain, 112IEEC-CSIC-UPC-UB, Barcelona, Spain, 113ASDC, Rome, Italy, 114University of Maryland, United States, 115University of Tasmania, Australia, 116MPA Garching, Germany, 117ASDC, Rome, Italy, 118INAF-IRA-Bologna, Italy, 119INAF-IRA-Bologna, Italy, 120Sabanci University, Istanbul, Turkey, 121APC, Université Paris Diderot, CEA/Irfu, Observatoire de Paris, France, 122Silesian University in Opava, Czech Republic, 123CEA Saclay, DSM/IRFU/SAp, France, 124CEA Saclay, DSM/IRFU/SAp, France, 125Pavia University, Italy, 126Clemson University, United States, 127IAAT Tuebingen, Germany, 128Sapienza University, Rome, Italy, 129Ferrara University, Ferrara, Italy, 130ISDC, Geneve University, Switzerland, 131SRON, The Netherlands, 132Copernicus Astronomical Center, Warsaw, Poland, 133MSSL, Surrey, United Kingdom, 134National Space Institute, Lyngby, Denmark, 135Clemson University, United States, 136Open University, United Kingdom, 137Institut für Kernphysik, Technische Universität Darmstadt and ExtreMe Matter Institute EMMI, GSI Helmholtzzentrum für Schwerionenforschung GmbH, Germany, 138Monash Centre for Astrophysics, School of Physics and School of Mathematical Sciences, Monash University, Australia, 139SRON, The Netherlands, 140MIT, Cambridge, United States, 141National Space Institute, Lyngby, Denmark, 142Astronomical Institute of the Academy of Sciences of the Czech Republic, Czech Republic, 143University of Helsinki, Finland, 144Astronomical Institute Anton Pannekoek, University of Amsterdam, The Netherlands, 145SRON, The Netherlands, 146INAF-OA Rome, Italy, 147DAM and ICC-UB, Universitat de Barcelona, Spain, 148Sapienza University and ICRA, Rome, Italy, 149SRON, The Netherlands, 150IAAT Tuebingen, Germany, 151Perimeter Institute for Theoretical Physics, Waterloo, Canada, 152SRON, The Netherlands, 153SRON, The Netherlands, 154Technical University of Catalonia, Barcelona, Spain, 155Michigan state University, United States, 156Max-Planck-Institut fuer extraterrestrische Physik, Garching, Germany, 157Astronomical Institute of the Academy of Sciences of the Czech Republic, Czech Republic, 158IEEC-CSIC-UPC-UB, Barcelona, Spain, 159MSSL, Surrey, United Kingdom, 160Michigan state University, United States, 161MSSL, Surrey, United Kingdom, 162IAAT Tuebingen, Germany, 163Copernicus Astronomical Center, Warsaw, Poland, 164IAAT Tuebingen, Germany, 165University of Helsinki, Finland, 166NASA/Marshall Space Flight Center, United States, 167University of Erlangen-Nuremberg, Germany, 168SRON, The Netherlands, 169National Space Institute, Lyngby, Denmark, 170INAF-IASF-Bologna, Italy, 171Cornell University, Ithaca, United States, 172University of Illinois, United States, 173SRON, The Netherlands, 174APC, Université Paris Diderot, CEA/Irfu, Observatoire de Paris, France, 175IRAP, Toulouse, France, 176MSSL, Surrey, United Kingdom, 177Dipartimento di Fisica, Università degli Studi di Milano, Italy, 178University of Trieste, Italy, 179National Space Institute, Lyngby, Denmark, 180Texas Tech. University, United States, 181Politecnico Milano, Italy, 182IRAP, Toulouse, France, 183University of Maryland, United States, 184IAAT Tuebingen, Germany, 185Pavia University, Italy, 186School of Physics and Astronomy, University of Birmingham, United Kingdom, 187The Pennsylvania State University, United States, 188Copernicus Astronomical Center, Warsaw, Poland, 189INAF-IASF-Bologna, Italy, 190University of California, San Diego, United States, 191Leicester University, United Kingdom, 192University of Rome III, Italy, 193School of Physics and Astronomy, University of Southampton, United Kingdom, 194University of Melbourne, Australia, 195Kapteyn Astronomical Institute, University of Groningen, The Netherlands, 196INAF-IASF-Milano, Italy, 197Space Research Centre, Warsaw, Poland, 198DAM and ICC-UB, Universitat de Barcelona, Spain, 199INAF-IASF-Milano, Italy, 200University of Maryland, United States, 201Michigan state University, United States, 202INAF IFC, Palermo, Italy, 203Centro de Astrobiologia, 204University of Alberta, Canada, 205Observatoire Astronomique de Strasbourg, France, 206INAF-OA Brera, Italy, 207Université Paris Diderot France, 208IRAP, Toulouse, France, 209National Space Institute, Lyngby, Denmark, 2101,1b, 211Oxford University, United Kingdom, 212University of Alicante, Spain, 213MIT, Cambridge, United States, 214Open University, United Kingdom, 215MIT, Cambridge, United States, 216Leicester University, United Kingdom, 217National Space Institute, Lyngby, Denmark, 218INAF-IRA-Bologna, Italy, 219INAF-OA Padova, Padova, Italy, 220INAF-IASF-Bologna, Italy, 221Space Research Centre, Warsaw, Poland, 222Leicester University, United Kingdom, 223Space Telescope Institute, United States, 224University of Arizona, United States, 2251,1b, 226Università di Napoli Fedelico II, Italy, 227IEEC-CSIC-UPC-UB, Barcelona, Spain, 228DAM and ICC-UB, Universitat de Barcelona, Spain, 229Leiden Observatory, The Netherlands, 230Raman Research Institute, India, 231IAAT Tuebingen, Germany, 232INAF-OA Cagliari, Italy, 233Sapienza University and ICRA, Rome, Italy, 234Facultad de Ciencias-Trilingüe University of Salamanca, Spain, 235Czech Technical University in Prague, Czech Republic, 236ASDC, Rome, Italy, 237University of Alicante, Spain, 238IEEC-CSIC-UPC-UB, Barcelona, Spain, 239INAF-OA Cagliari, Italy, 240Tuorla Observatory, University of Turku, Finland, 241Ohio University, United States, 242CEA Saclay, DSM/IRFU/SAp, France, 243University of Arizona, United States, 244IRAP, Toulouse, France, 245IRAP, Toulouse, France, 246Armagh Observatory, United Kingdom, 2471,1b, 248INFN, Trieste, Italy, 249INFN, Trieste, Italy, 250NRL, Washington, United States, 251IEEC-CSIC-UPC-UB, Barcelona, Spain, 252Institute for Nuclear Theory, University of Washington, United States, 253Foundation for Research and Technology, Heraklion, Greece, 254National Institute of Aerospace Technology, 255MIT, Cambridge, United States, 256University of Maryland, United States, 257Max Planck Institute for Gravitational Physics, Germany, 258DAM and ICC-UB, Universitat de Barcelona, Spain, 259SRON, The Netherlands, 260INAF-OA Cagliari, Italy, 261University of Surrey, United Kingdom, 262Instituto de Astrofisica de Canarias, Tenerife, Spain, 263CEA Saclay, DSM/IRFU/SAp, France, 264ISDC, Geneve University, Switzerland, 265INAF IFC, Palermo, Italy, 266Leiden Observatory, The Netherlands, 267Copernicus Astronomical Center, Warsaw, Poland, 268MSSL, Surrey, United Kingdom, 269KTH Royal Institute of Technology, Stockholm, Sweden, 270National Institute of Aerospace Technology, 271IEEC-CSIC-UPC-UB, Barcelona, Spain, 272INAF-IASF-Milano, Italy, 273Kapteyn Astronomical Institute, University of Groningen, The Netherlands, 274Jorgen Sandberg Consulting, Denmark, 275Institute for Astronomy K.U. Leuven, Leuven, Belgium, 276CEA Saclay, DSM/IRFU/SAp, France, 277Silesian University in Opava, Czech Republic, 278University of Erlangen-Nuremberg, Germany, 279University of Pisa, Italy, 280INAF-OA Rome, Italy, 281Institut für Kernphysik, Technische Universität Darmstadt and ExtreMe Matter Institute EMMI, GSI Helmholtzzentrum für Schwerionenforschung GmbH, Germany, 282Leibniz-Institut fuer Astrophysik Potsdam, Germany, 283CNES, Toulouse, France, 284National University of Ireland, Ireland, 285MSSL, Surrey, United Kingdom, 286University of California, United States, 287MSSL, Surrey, United Kingdom, 288Astronomical Institute of the Academy of Sciences of the Czech Republic, Czech Republic, 289IAPS-INAF, Rome, Italy, 290Kapteyn Astronomical Institute, University of Groningen, The Netherlands, 291MSSL, Surrey, United Kingdom, 292University of Manchester, United Kingdom, 293Institute for Nuclear Theory, University of Washington, United States, 294Aristotle University of Thessaloniki, Greece, 295ASDC, Rome, Italy, 296Goddard Space Flight Center, Greenbelt, United States, 297Silesian University in Opava, Czech Republic, 298IAAT Tuebingen, Germany, 299IAAT Tuebingen, Germany, 300ISAS, Kanagawa, Japan, 301Dept. of Physics and Astronomy University of Padua, Italy, 302Argelander-Institut für Astronomie, Bonn, Germany, 303IAAT Tuebingen, Germany, 304IEEC-CSIC-UPC-UB, Barcelona, Spain, 305University of Maryland, United States, 306University of California, Berkeley, Space Sciences Laboratory, United States, 307Silesian University in Opava, Czech Republic, 308University of Alicante, Spain, 309ICREA, Barcelona, Spain, 310ISDC, Geneve University, Switzerland, 311IAPS-INAF, Rome, Italy, 312Dept. of Physics and Astronomy University of Padua, Italy, 313University of Rome Tor Vergata, Italy, 314IAAT Tuebingen, Germany, 315Astronomical Institute Anton Pannekoek, University of Amsterdam, The Netherlands, 316INFN, Trieste, Italy, 317APC, Université Paris Diderot, CEA/Irfu, Observatoire de Paris, France, 318Leicester University, United Kingdom, 319INAF IFC, Palermo, Italy, 320Physical Institute of the Academy of Sciences of the Czech Republic, Czech Republic, 321MSSL, Surrey, United Kingdom, 322ISAS, Kanagawa, Japan, 323Space Research Centre, Warsaw, Poland, 324IRAP, Toulouse, France, 325MIT, Cambridge, United States, 326IAAT Tuebingen, Germany, 327University of Warwick, United Kingdom, 328Astronomical Institute Anton Pannekoek, University of Amsterdam, The Netherlands, 329Astronomical Institute Anton Pannekoek, University of Amsterdam, The Netherlands, 330University of Erlangen-Nuremberg, Germany, 331NASA/Marshall Space Flight Center, Huntsville, United States, 332MSSL, Surrey, United Kingdom, 333NRL, Washington, United States, 334INFN, Trieste, Italy, 335INFN, Trieste, Italy, 336INAF-OA Padova, Padova, Italy, 337Copernicus Astronomical Center, Warsaw, Poland, 338Copernicus Astronomical Center, Warsaw, Poland, 339University of Nevada, Las Vegas, United States, 340SRON, The Netherlands, 341European Space Agency, ESTEC, The Netherlands, 342European Space Agency, ESTEC, The Netherlands, 343European Space Agency, ESTEC, The Netherlands, 344European Space Astronomy Centre, Madrid, Spain, 345European Space Agency, ESTEC, The Netherlands

The Large Observatory For x-ray Timing (LOFT) was studied within ESA M3 Cosmic Vision framework and participated in the final down-selection for a launch slot in 2022-2024. Thanks to the unprecedented combination of effective area and spectral resolution of its main instrument, LOFT will study the behaviour of matter under extreme conditions, such as the strong gravitational field in the innermost regions of accretion flows close to black holes and neutron stars, and the supra-nuclear densities in the interior of neutron stars. The science payload is based on a Large Area Detector (LAD, 10 m 2 effective area, 2-30 keV, 240 eV spectral resolution, 1 deg collimated field of view) and a WideField Monitor (WFM, 2-50 keV, 4 steradian field of view, 1 arcmin source location accuracy, 300 eV spectral resolution). Read More

2014Jul
Affiliations: 1INAF-Osservatorio Astronomico di Brera, 2INAF-Osservatorio Astronomico di Roma

Currently available information on fast variability of the X-ray emission from accreting collapsed objects constitutes a complex phenomenology which is difficult to interpret. We review the current observational standpoint for black-hole binaries and survey models that have been proposed to interpret it. Despite the complex structure of the accretion flow, key observational diagnostics have been identified which can provide direct access to the dynamics of matter motions in the close vicinity of black holes and thus to the some of fundamental properties of curved spacetimes, where strong-field general relativistic effects can be observed. Read More

We have systematically studied a large sample of the neutron star low mass X-ray binaries (LMXBs) monitored by the Rossi X-ray Timing Explorer (50 sources; 10000+ observations). We find that the hysteresis patterns between Compton dominated and thermal dominated states, typically observed in black hole LMXBs, are also common in neutron star systems. These patterns, which also sample intermediate states, are found when looking at the evolution of both X-ray colour and fast variability of ten systems accreting below ~ 30 % of the Eddington Luminosity. Read More

We present a systematic study of the orbital inclination effects on black-hole transients fast time-variability properties. We have considered all the black-hole binaries that have been densely monitored by the Rossi XTE satellite. We find that the amplitude of low-frequency quasi periodic oscillations (QPOs) depends on the orbital inclination. Read More

Both the broad iron (Fe) line and the frequency of the kilohertz quasi-periodic oscillations (kHz QPOs) in neutron star low-mass X-ray binaries (LMXBs) can potentially provide independent measures of the inner radius of the accretion disc. We use XMM-Newton and simultaneous Rossi X-ray Timing Explorer observations of the LMXB 4U 1636-53 to test this hypothesis. We study the properties of the Fe-K emission line as a function of the spectral state of the source and the frequency of the kHz QPOs. Read More

We used six simultaneous XMM-Newton and Rossi X-ray Timing Explorer plus five Suzaku observations to study the continuum spectrum and the iron emission line in the neutron-star low-mass X-ray binary 4U 1636-53. We modelled the spectra with two thermal components (representing the accretion disc and boundary layer), a Comptonised component (representing a hot corona), and either a Gaussian or a relativistic line component to model an iron emission line at about 6.5 keV. Read More

We select a sample of nearby Ultraluminous X-ray sources with long XMM-Newton observations and analyse all the available XMM-Newton data using both X-ray spectral fitting techniques and hardness-intensity diagrams. The sample includes IC 342 X-1, NGC 5204 X-1, NGC 5408 X-1, Holmberg IX X-1, Holmberg II X-1, NGC 1313 X-1, NGC 1313 X-2 and NGC 253 X-1. We found that, although a common reference model can be used to describe the X-ray spectra, the sources show different spectral evolutions, phenomenologically described in terms of variations in the properties of a soft component and a high energy tail. Read More

We present a systematic analysis of the complete set of observations of the black hole (BH) binary XTE J1550-564 obtained by the Rossi X-ray Timing Explorer. We study the fast time variability properties of the source and determine the spin of the black hole through the relativistic precession model. Similarly to what is observed in the BH binary GRO J1655-40, the frequencies of the QPOs and broad band noise components match the general relativistic frequencies of particle motion close to the compact object predicted by the relativistic precession model. Read More

We present the analysis of the X-ray variability and spectral timing properties of the ultraluminous X-ray source (ULX) NGC 5408 X-1, one of the most variable ULXs known so far. The variability properties are used as a diagnostic of the accretion state of the source and to derive estimates of the black hole (BH) mass. The observed high level of fast X-ray variability (fractional root-mean-square variability - rms - amplitude of $\sim$ 30 percent in the hard energy band), the hardening of the fractional rms spectrum, and the properties of the QPO, all resemble those of a source in a hard-intermediate accretion state. Read More

2013Sep
Affiliations: 1Osservatorio Astronomico di Brera, Merate, 2Osservatorio Astronomico di Brera, Merate, 3Osservatorio Astronomico di Padova

Ultra-Luminous X-ray sources are thought to be accreting black holes that might host Intermediate Mass Black Holes (IMBH), proposed to exist by theoretical studies, even though a firm detection (as a class) is still missing. The brightest ULX in M82 (M82 X-1) is probably one of the best candidates to host an IMBH. In this work we analyzed the data of the recent release of observations obtained from M82 X-1 taken by XMM-Newton. Read More

2013Sep
Affiliations: 1Curtin/ICRAR, 2U Cape Town, 3Curtin/ICRAR, 4U Cape Town, 5CSIRO/CASS, 6U Alberta, 7U Cape Town, 8U Amsterdam, 9INAF/OAB, 10AIM/CEA-Saclay, 11U Southampton, 12Radboud U, 13USRA, 14U Amsterdam, 15U Barcelona, 16IAC, 17CSIRO/CASS, 18CSIRO/CASS

Swift J1745-26 is an X-ray binary towards the Galactic Centre that was detected when it went into outburst in September 2012. This source is thought to be one of a growing number of sources that display "failed outbursts", in which the self-absorbed radio jets of the transient source are never fully quenched and the thermal emission from the geometrically-thin inner accretion disk never fully dominates the X-ray flux. We present multifrequency data from the Very Large Array, Australia Telescope Compact Array and Karoo Array Telescope (KAT- 7) radio arrays, spanning the entire period of the outburst. Read More

We present a systematic analysis of the fast time variability properties of the transient black hole binary GRO J1655-40, based on the complete set of RossiXTE observations. We demonstrate that the frequencies of the quasi-periodic oscillations and of the broad band noise components and their variations match accurately the strong field general relativistic frequencies of particle motion in the close vicinity of the innermost stable circular orbit, as predicted by the relativistic precession model. We obtain high precision measurements of the black hole mass (M = (5. Read More

MAXI J1659-152 was discovered on 2010 September 25 as a new X-ray transient, initially identified as a gamma-ray burst, but was later shown to be a new X-ray binary with a black hole as the most likely compact object. Dips in the X-ray light curves have revealed that MAXI J1659-152 is the shortest period black hole candidate identified to date. Here we present the results of a large observing campaign at radio, sub-millimeter, near-infrared (nIR), optical and ultraviolet (UV) wavelengths. Read More

2013Aug

The notion of source states characterizing the X-ray emission from black hole binaries has revealed to be a very useful tool to disentangle the complex spectral and aperiodic phenomenology displayed by those classes of accreting objects. We seek to use the same tools for Ultra-Luminous X-ray (ULX) sources. We analyzed the data from the longest observations obtained from the ULX source in NGC 5408 (NGC 5408 X-1) taken by XMM-Newton. Read More

2013Aug
Affiliations: 1Kapteyn Astronomical Institute, University of Groningen, The Netherlands, 2University of Amsterdam, The Netherlands, 3INAF-Osservatorio Astronomico di Brera, Italy, 4Dipartimento di Fisica, Universita degli Studi di Cagliari, Italy

We measured the phase-lag spectrum of the high-frequency quasi-periodic oscillations (QPO) in the black hole systems (at QPO frequencies) GRS 1915+105 (35 Hz and 67 Hz), GRO J1655-40 (300 Hz and 450 Hz), XTE J1550-564 (180 Hz and 280 Hz), and IGR J17091-3624 (67 Hz). The lag spectra of the 67-Hz QPO in, respectively, GRS 1915+105 and IGR J17091-3624, and the 450-Hz QPO in GRO J1655-40 are hard (hard photons lag the soft ones) and consistent with each other, with the hard lags increasing with energy. On the contrary, the lags of the 35-Hz QPO in GRS 1915+105 are soft, with the lags becoming softer as the energy increases; the lag spectrum of the 35-Hz QPO is inconsistent with that of the 67-Hz QPO. Read More

The microquasar GRS1915+105 was observed by BeppoSAX in October 2000 for about ten days while the source was in \rho-mode, which is characterized by a quasi-regular type I bursting activity. This paper presents a systematic analysis of the delay of the hard and soft X-ray emission at the burst peaks. The lag, also apparent from the comparison of the [1. Read More

We report striking changes in the broadband spectrum of the compact jet of the black hole transient MAXI J1836-194 over state transitions during its discovery outburst in 2011. A fading of the optical-infrared (IR) flux occurred as the source entered the hard-intermediate state, followed by a brightening as it returned to the hard state. The optical-IR spectrum was consistent with a power law from optically thin synchrotron emission, except when the X-ray spectrum was softest. Read More

The X-ray transient MAXI J1659-152 was discovered by Swift/BAT and it was initially identified as a GRB. Soon its Galactic origin and binary nature were established. There exists a wealth of multi-wavelength monitoring data for this source, providing a great coverage of the full X-ray transition in this candidate black hole binary system. Read More

We present a 30-day monitoring campaign of the optical counterpart of the bright X-ray transient Swift J1745-26, starting only 19 minutes after the discovery of the source. We observe the system peaking at i' ~17.6 on day 6 (MJD 56192) to then decay at a rate of ~0. Read More

2013Mar
Affiliations: 1Groningen, 2Groningen, 3Groningen, 4Amsterdam, 5INAF-OAB, 6Canary Islands

We analysed the X-ray spectra of six observations, simultaneously taken with XMM-Newton and Rossi X-ray Timing Explorer (RXTE), of the neutron star low-mass X-ray binary 4U 1636-53. The observations cover several states of the source, and therefore a large range of inferred mass accretion rate. These six observations show a broad emission line in the spectrum at around 6. Read More

2013Mar
Affiliations: 1INAF-Osservatorio Astronomico di Brera, Italy, 2University of Amsterdam, the Netherlands

We report the discovery in the Rossi X-Ray Timing Explorer data of GRS 1915+105 of a second quasi-periodic oscillation at 34 Hz, simultaneous with that observed at 68 Hz in the same observation. The data corresponded to those observations from 2003 where the 68-Hz oscillation was very strong. The significance of the detection is 4. Read More

2013Mar
Affiliations: 1INAF-Osservatorio Astronomico di Brera, Italy, 2University of Amsterdam, the Netherlands

We report the results of a systematic timing analysis of all archival Rossi X-Ray Timing Explorer (RXTE) observations of the bright black-hole binary GRS 1915+105 in order to detect high-frequency quasi-periodic oscillations (HFQPO). We produced power-density spectra in two energy bands and limited the analysis to the frequency range 30-1000 Hz. We found 51 peaks with a single trial significance larger than 3 sigma. Read More

We present a spectral analysis of the black hole candidate and X-ray transient source Swift J1753.5 0127 making use of simultaneous observations of XMM-Newton and Rossi X-ray Timing Explorer (RXTE) in 2006, when the source was in outburst. The aim of this paper is to test whether a thermal component due to the accretion disc is present in the X-ray spectrum. Read More

2013Jan

We present the first X-ray study of NGC6791, one of the oldest open clusters known (8 Gyr). Our Chandra observation is aimed at uncovering the population of close interacting binaries down to Lx ~ 1e30 erg/s (0.3-7 keV). Read More

We present a study of correlations between spectral and timing parameters for a sample of black hole X-ray binary candidates. Data are taken from GX 339-4, H 1743-322, and XTE J1650-500, as the Rossi X-ray Timing Explorer (RXTE) observed complete outbursts of these sources. In our study we investigate outbursts that happened before the end of 2009 to make use of the high-energy coverage of the HEXTE detector and select observations that show a certain type of quasi-periodic oscillations (type-C QPOs). Read More

2012Nov
Affiliations: 1U. Groningen, 2U. Southampton, 3ESAC, 4INAF-OAB, 5INAF-OAR, 6U. Groningen, 7U. Amsterdam, 8IAC, 9U. Amsterdam, 10U. Southampton, 11U. Amsterdam

We present our monitoring campaign of the outburst of the black-hole candidate Swift J1753.5-0127, observed with the Rossi X-ray Timing Explorer and the Swift satellites. After ~4. Read More

We use data of the bright atoll source 4U 1705-44 taken with XMM-Newton, BeppoSAX and RXTE both in the hard and in the soft state to perform a self-consistent study of the reflection component in this source. Although the data from these X-ray observatories are not simultaneous, the spectral decomposition is shown to be consistent among the different observations, when the source flux is similar. We therefore select observations performed at similar flux levels in the hard and soft state in order to study the spectral shape in these two states in a broad band (0. Read More