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A J Castro-Tirado,
A de Ugarte Postigo,
J Gorosabel,
M Jelínek,
T A Fatkhullin,
V V Sokolov,
P Ferrero,
D A Kann,
S Klose,
D Sluse, [......],
T Shahbaz,
S Guziy,
S B Pandey,
L Pavlenko,
E Sonbas,
S A Trushkin,
N N Bursov,
N A Nizhelskij, C Sánchez-Fernández,
L Sabau-Graziati
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ABSTRACT: Magnetars are young neutron stars with very strong magnetic fields of the order of 10(14)-10(15) G. They are detected in our Galaxy either as soft gamma-ray repeaters or anomalous X-ray pulsars. Soft gamma-ray repeaters are a rare type of gamma-ray transient sources that are occasionally detected as bursters in the high-energy sky. No optical counterpart to the gamma-ray flares or the quiescent source has yet been identified. Here we report multi-wavelength observations of a puzzling source, SWIFT J195509+261406. We detected more than 40 flaring episodes in the optical band over a time span of three days, and a faint infrared flare 11 days later, after which the source returned to quiescence. Our radio observations confirm a Galactic nature and establish a lower distance limit of approximately 3.7 kpc. We suggest that SWIFT J195509+261406 could be an isolated magnetar whose bursting activity has been detected at optical wavelengths, and for which the long-term X-ray emission is short-lived. In this case, a new manifestation of magnetar activity has been recorded and we can consider SWIFT J195509+261406 to be a link between the 'persistent' soft gamma-ray repeaters/anomalous X-ray pulsars and dim isolated neutron stars.
Nature 10/2008; 455(7212):506-9. · 36.28 Impact Factor
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A. de Ugarte Postigo,
A. J. Castro‐Tirado,
M. Jelínek,
P. Kubánek,
R. Cunnife,
J. Gorosabel,
S. Vitek,
S. Castillo‐Carrión,
S. Guziy,
S. B. Pandey, [......],
V. de Caprio,
P. Amado,
A. Claret,
C. Cardenas,
S. Martín,
J. M. Trigo‐Rodriguez, C. Sánchez‐Fernández,
M. D. Sabau‐Graziati,
J. Díaz‐Verdejo,
F. Vitali
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ABSTRACT: BOOTES‐IR is the natural evolution of BOOTES (Burst Observer and Optical Transient Exploring System) towards the near‐infrared (NIR). Using the experience gathered during the last 7 years, we are developing a powerful tool for the detection and study of Gamma‐Ray Burst (GRB) afterglows. The system includes a custom developed robotic observatory software (RTS2) that manages all the instruments and devices of the observatory to make them work together in an optimal way. Additionally we have created a package of real time reduction and analysis tools (JIBARO) that allow us to automatically identify GRB afterglow candidates. The telescope, a 0.6m Ritchey‐Chrètien, now in commissioning phase, is capable of pointing with a typical delay of 5 seconds between arrival of the alert and start of the first exposure. The NIR camera, with 1024 × 1024 pixels and a field of view of 12′ × 12′ will see first light in Spring 2006 and is expected to be in normal operation during the Summer. An optical camera working in parallel will complement observations. © 2006 American Institute of Physics
AIP Conference Proceedings. 05/2006; 836(1):668-671.
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ABSTRACT: In all the hospital library standards, as well as in the existing Accreditation Norms for hospitals, a section is included which cites the distinct professionals who work at the institution which the library services must attend to provide for their scientific information needs. Among the sanitary collectives, nursing professionals are explicitly listed. Nonetheless, since the creation of hospital library services in Spain, many librarians have noticed that the nursing professionals, which compose the most numerous group in a hospital, have a very low library visitation rate in relationship to other collectives such as doctors in particular. Desiring to have objective data regarding library use, and not merely perceptions, the authors planned out a study in a large, 1.200 bed, hospital where more than 1.000 professionals comprise the nursing staff. The authors wanted to verify the nursing staff's needs for scientific information, their habits regarding their scientific information needs, and the possible difficulties which they encounter trying to acquire this type of information; furthermore, the authors wanted to know the nursing professionals' attitude towards this issue.
Revista de enfermeria (Barcelona, Spain) 04/2006; 29(3):19-22.
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C. Zurita, C. Sánchez-Fernández,
J. Casares,
P. A. Charles,
T. M. Abbott,
P. Hakala,
P. Rodríguez-Gil,
S. Bernabei,
A. Piccioni,
A. Guarnieri,
C. Bartolini,
N. Masetti,
T. Shahbaz,
A. Castro-Tirado,
A. Henden
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ABSTRACT: We present optical photometry and spectroscopy of the X-ray transient XTE J1859+226, obtained during outburst and its subsequent decay to quiescence. Both the X-ray and optical properties are very similar to those of well-studied black hole soft X-ray transients. We have detected three mini-outbursts, when XTE J1859+226 was approaching quiescence, as has been previously detected in the soft X-ray transients GRO J0422+32 and GRS 1009–45. By 2000 August 24 the system had reached quiescence with R= 22.48 ± 0.07. The estimated distance to the source is ∼11 kpc. Photometry taken during quiescence shows a sinusoidal modulation with a peak to peak amplitude of about 0.4 mag. A period analysis suggests that periods from 0.28 to 0.47 d are equally possible at the 68 per cent confidence level. The amplitude of the quiescent light curve and the relatively low ratio of X-ray to optical flux indicate that the binary inclination should be high. The measured colours during the outburst allow us to obtain the basic properties of the disc, which agrees well with irradiated disc model predictions.
Monthly Notices of the Royal Astronomical Society 07/2002; 334(4):999 - 1008. · 4.90 Impact Factor
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ABSTRACT: Photometry of the X-ray transient XTE J1859+226, obtained during outburst,showed at least 3 minioutbursts. During the second one, the source exhibiteda 0.3 mag modulation with QPO flaring activity during the minimum.
Astrophysics and Space Science 12/2000; 276:55-56. · 1.69 Impact Factor
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Alberto J. Castro-Tirado,
A. de Ugarte Postigo,
J. Gorosabel,
M. Jelínek,
T. A. Fatkhullin,
V. B. Sokolov,
P. Ferrero,
D. A. Kann,
S. Klose,
D. Sluse, [......],
T. Shahbaz,
S. Guziy,
S. B. Pandey,
L. Pavlenko,
E. Sonbas,
S. A. Trushkin,
N. N. Bursov,
N. A. Nizhelskij, C. Sánchez-Fernández,
L. Sabau-Graziati
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ABSTRACT: This work is based on observations carried out with the 0.3-m robotic telescope at the Spanish BOOTES-2 astronomical station of the Estación Experimental de La Mayora (CSIC), the 0.4-m WATCHER telescope operated by UCD at Boyden Observatory (South Africa), the 0.8-m IAC telescope at the Spanish Observatorio de Izaña of the Instituto de Astrofísica de Canarias (IAC), the 1.2-m Mercator telescope operated by the Flemish Community at the Spanish Observatorio del Roque de los Muchachos of the IAC, the 1.34-m telescope at the Tautenburg Observatory (Germany), the 1.5-m OSN telescope at the Spanish Observatorio de Sierra Nevada of the Instituto de Astrofísica de Andalucía (CSIC), the 6.0-m BTA telescope at the Special Astrophysical Observatory of the Russian Academy of Sciences, the 8.2-m VLT telescope of the European Southern Observatory at Paranal (Chile), the IRAM 30-m and Plateau de Bure Telescopes and the 100-m telescope of the Max-Planck-Institut für Radioastronomie at Effelsberg (Germany). IRAM is supported by INSU/CNRS (France), MPG (Germany) and IGN (Spain). 4 pages, 4 figures.-- ArXiv pre-print version available at: http://arxiv.org/abs/0809.4231. Magnetars are young neutron stars with very strong magnetic fields of the order of 1014-1015G. They are detected in our Galaxy either as soft γ-ray repeaters or anomalous X-ray pulsars. Soft γ-ray repeaters are a rare type of γ-ray transient sources that are occasionally detected as bursters in the high-energy sky. No optical counterpart to the γ-ray flares or the quiescent source has yet been identified. Here we report multi-wavelength observations of a puzzling source, SWIFT J195509+261406. We detected more than 40 flaring episodes in the optical band over a time span of three days, and a faint infrared flare 11days later, after which the source returned to quiescence. Our radio observations confirm a Galactic nature and establish a lower distance limit of ~3.7kpc. We suggest that SWIFT J195509+261406 could be an isolated magnetar whose bursting activity has been detected at optical wavelengths, and for which the long-term X-ray emission is short-lived. In this case, a new manifestation of magnetar activity has been recorded and we can consider SWIFT J195509+261406 to be a link between the `persistent' soft γ-ray repeaters/anomalous X-ray pulsars and dim isolated neutron stars. D.A.K. and S.K. acknowledge financial support by DFG and D.P.R. from Junta de Andalucía. L.H. acknowledges support from IRCSET and SFI. R.H. acknowledges support from PECs and GACR. This work was partially supported by the Spanish Ministry of Science and Innovation. Peer reviewed
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A. J. Castro-Tirado,
J. M. Castro Cerón,
J. Gorosabel,
P. Páta,
J. Soldán,
R. Hudec,
M. Jelinek,
M. Topinka,
M. Bernas,
T. J. Mateo Sanguino, [......],
B. Canzian,
H. Harris,
X. Delfosse,
B. de Pontieu,
J. Polcar, C. Sánchez-Fernández,
B. A. de la Morena,
J. M. Más Hesse,
J. Torres Riera,
S. Barthelmy
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ABSTRACT: We imaged the error box of a gamma-ray burst of the short (0.5 s), hard type (GRB 000313), with the BOOTES-1 experiment in southern Spain, starting 4 min after the $\gamma$–ray event, in the $I$-band. A bright optical transient (OT 000313) with $I = 9.4 \pm 0.1$ was found in the BOOTES-1 image, close to the error box (3$\sigma$) provided by BATSE. Late time $VRIK^\prime$-band deep observations failed to reveal an underlying host galaxy. If the OT 000313 is related to the short, hard GRB 000313, this would be the first optical counterpart ever found for this kind of events (all counterparts to date have been found for bursts of the long, soft type). The fact that only prompt optical emission has been detected (but no afterglow emission at all, as supported by theoretical models) might explain why no optical counterparts have ever been found for short, hard GRBs. This fact suggests that most short bursts might occur in a low-density medium and favours the models that relate them to binary mergers in very low-density environments.
http://dx.doi.org/10.1051/0004-6361:20021172.
