503 research outputs found
The hard state of black hole candidates: XTEJ1752-223
No full textWe present a 2-day long Rossi X-ray Timing Explorer observation and simultaneous Swift data of the bright X-ray transient XTE J1752–223. Spectral and timing properties were stable during the observation. The energy spectrum is well described by a broken power law with a high-energy cut-off. A cold disc (?0.3 keV) is observed when Swift/X-Ray Telescope data are considered. The fractional root mean square amplitude of the aperiodic variability (0.002–128 Hz) is 48.2 ± 0.1 per cent, and it is not energy dependent. The continuum of the power density spectrum can be fitted by using four broad-band Lorentzians. A high-frequency (?21 Hz) component and two weak quasi-periodic oscillation-like features are also present. Time lags between soft and hard X-rays roughly follow the relation ?t???0.7, with delays dropping from ?0.5 (0.003 Hz) to ?0.0015 (?10 Hz) s. Our results are consistent with XTE J1752–223 being a black hole candidate, with all timing and spectral components very similar to those of Cyg X-1 during its canonical hard state
INTEGRAL detection of renewed activity from BHC IGR J17091-3624: Developing towards a state transition?
No full textAuthors: Rodriguez (CEA, F), C. Ferrigno (ISDC, CH), T. Bouchet (CEA/AIM, F), F. Cangemi (APC, F), V. Grinberg (ESA, NL), P. Laurent (CEA/AIM, F), K. Pottschmidt (CRESST/NASA/UMBC, USA), P. Thalhammer (Remeis Observatory, D), J. Wilms (Remeis Observatory, D)https://www.astronomerstelegram.org/?read=1703
IGR J18175-1530: a new hard X-ray transient detected by INTEGRAL
No full textAuthors: - A. Paizis, V. Beckmann, D. Gotz, L. Sidoli, A. Bazzano, G. Belanger, M. Cadolle-Bel, J. Chenevez, A. De Rosa, E. Kuulkers, M. Falanga, M. Fiocchi, L. Kuiper, J. C. Leyder, S. Mereghetti, S. Piraino, K. Pottschmidt, S. Shaw, J. Tomsick, K. Watanabe, R. Walter, G. Weidenspointnerhttps://www.astronomerstelegram.org/?read=124
INTEGRAL observation of a bright X-ray outburst of XTE J1739-302 / IGR J17391-3021
No full textAuthors: - Turler, M.; Balman, S.; Bazzano, A.; Beckmann, V.; Belloni, T.; Boggs, S.; Capitanio, F.; Chenevez, J.; Del Santo, M.; Diehl, R.; Donnarumma, I.; Eckert, D.; Goldoni, P.; Gotz, D.; Leyder, J. -C.; Mereghetti, S.; Paizis, A.; Pottschmidt, K.; Sidoli, L.; Tarana, A.; Tueller, J.; Walter, R.; Watanabe, K.; Weidenspointner, G.https://www.astronomerstelegram.org/?read=101
SAX J1810.8-2609 displays increasing hard X-ray activity
No full textAuthors: - R. Galis, V. Beckmann, J. Chenevez, S. Brandt, G. Belanger, E. Kuulkers, M. Cadolle Bel, C. Sanchez-Fernandez, A. Bazzano, I. Donnarumma, M. Fiocchi, L. Natalucci, D. Götz, W. Hermsen, J.-C. Leyder, S. Piraino, K. Pottschmidt, N. Shaposhnikov, A. Paizis, L. Sidoli, J. Tomsick, R. Walter, K. Watanabehttps://www.astronomerstelegram.org/?read=122
IGR J17497-2821: a new hard X-ray transient detected by INTEGRAL
No full textAuthors: - Soldi, S.; Walter, R.; Eckert, D.; Balman, S.; Bazzano, A.; Beckmann, V.; Belloni, T.; Boggs, S.; Capitanio, F.; Chenevez, J.; Del Santo, M.; Diehl, R.; Donnarumma, I.; Goldoni, P.; Gotz, D.; Leyder, J. -C.; Mereghetti, S.; Paizis, A.; Pottschmidt, K.; Sidoli, L.; Tarana, A.; Tueller, J.; Watanabe, K.; Weidenspointner, G.https://www.astronomerstelegram.org/?read=88
INTEGRAL detection of high energy emission from XMMSL1 J171900.4-353217
No full textAuthors: - W. Ishibashi, E. Bozzo, R. Terrier, S. Mereghetti, A. Paizis, L. Ducci, D. Gotz, A. Bazzano, M. Fiocchi, A. De Rosa, A. Tarana, M. Del Santo, L. Natalucci, F. Panessa, F. Capitanio, V. Sguera, V. Bianchin, K. Watanabe, L. Kuiper, L. Barragan, J. Chenevez, I. Caballero, C. Shrader, A. Bird, G. Puehlhofer, C. Sanchez-Fernandez, G. Skinner, P. R. den Hartog, K. Pottschmidt, I. Negueruela, L. Prathttps://www.astronomerstelegram.org/?read=280
XTE J1810-189 measurements by INTEGRAL and Swift
No full textAuthors: A. Neronov, V. Beckmann, H. Krimm, C. B. Markwardt, J. Tueller, L. Kuiper, A. Bazzano, I. Donnarumma, A. De Rosa, M. Fiocchi, L. Natalucci, M. Cadolle-Bel, M. Falanga, A. Goldwurm, J.-C. Leyder, S. Mereghetti, S. Piraino, Katja Pottschmidt, J. Tomsick, R. Walter, and K. Watanabehttps://astronomerstelegram.org/?read=143
XRISM/Xtend Transient Search (XTS) detected an X-ray flare from XRISM J1733-2440
No full textAuthors: Y. Ishihara (Chuo U.), K. Fukushima, K. Hayashi, Y. Kanemaru, S. Ogawa, T. Yoshida (JAXA), M. Audard (U. de Geneve), E. Behar (Technion), S. Inoue (Kyoto U.), T. Kohmura (TUS), Y. Maeda (JAXA), M. Mizumoto (UTEF), N. Nagashima (Chuo U.), M. Nobukawa (NUE), K. Pottschmidt (UMBC, NASA GSFC, CRESST), M. Shidatsu (Ehime U.), H. Sugai (Chuo U.), Y. Terada (Saitama U.), Y. Terashima (Ehime U.), Y. Tsuboi (Chuo U.), H. Uchida (Kyoto U.), T. Yanagi (Chuo U.), T. Yoneyama (Chuo U.), M. Yoshimoto (Osaka U.).XRISM/Xtend Transient Search (XTS) detected an X-ray flare from an X-ray source XRISM J1733-2440 on 2025-03-25 TT. The source position is determined to be (R.A., Dec.) = (263.262, -24.588), with a systematic error of ∼ 40 arcsec. A plausible counterpart is X-ray sources 1WGA J1733.0-2435, 4XMMs J173302.1-243510, or 2RXP J173302.0-243510. They are located within 15 arcsec from the position of XRISM J1733-2440.
The flare reached its peak on 2025-03-25 at ∼ 15:19. The flare exponentially decayed in 8 × 10³ sec. The flux at the flare peak is estimated as 6 × 10⁻¹³ erg s⁻¹ cm⁻² (0.4 – 10.0 keV). A systematic error of roughly 20% should be added to the statistical error. We estimated the systematic error for the source position from the separations between the detected sources with the corresponding counterparts in the same field of view.https://www.astronomerstelegram.org/?read=1711
Detection of GRS 1915+105 and SS 433 at 7.2 GHz and 21.4 GHz with the Sardinia Radio Telescope
No full textAuthors: E. Egron, A. Pellizzoni, M. Bachetti, A. Navarrini, A. Trois, M. Pilia, M. N. Iacolina, A. Melis, R. Concu, S. Loru, R. Ballhausen, S. Corbel, W. Eikmann, F. Fuerst, V. Grinberg, I. Kreykenbohm, M. Marongiu, M. Nowak, A. Possenti, K. Pottschmidt, J. Rodriguez, J. Wilmshttps://astronomerstelegram.org/?read=892
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