The first outburst of the new magnetar candidate SGR 0501+4516 (2009)
Rea, Nanda, Israel, GianLuca, Turolla, Roberto, Esposito, Paolo, Mereghetti, Sandro, Gotz, Diego, ...
We report here on the outburst onset and evolution of the new Soft Gamma Repeater SGR 0501+4516. We monitored the new SGR with XMM-Newton starting on 2008 August 23, one day after the source became...
Resonant cyclotron scattering in magnetars' emission (2008)
Rea, Nanda, Zane, Silvia, Turolla, Roberto, Lyutikov, Maxim, Gotz, Diego
(Abridged) We present a systematic fit of a model of resonant cyclotron scattering (RCS) to the X-ray data of ten magnetars, including canonical and transient anomalous X-ray pulsars (AXPs), and soft...
Anatomy of a dark burst - the afterglow of GRB 060108 (2007)
Oates, Samantha R., Mundell, Carole G., Piranomonte, Silvia, Page, Kim L., De Pasquale, Massimiliano, Monfardini, Alessandro, ...
We report the first detection of an optical afterglow of a GRB (060108) that would have been classified as 'dark' in the absence of deep, rapid ground-based optical imaging with the 2-m robotic...
Silvia Zane, Roberto Turolla, Luciano Nobili, Myris Erna
INTRODUCTION Radiative transfer in high energy, fast moving plasmas in a strong gravitational field is today at the basis of a large number of currently interesting astrophysical applications:...
Spectral modelling of the high energy emission of the magnetar 4U 0142+614 (2007)
Rea, Nanda, Turolla, Roberto, Zane, Silvia, Tramacere, Andrea, Stella, Luigi, Israel, Gianluca, ...
We present an empirical spectral modelling of the high energy emission of the anomalous X-ray pulsar 4U 0142+614, based on simultaneous Swift and INTEGRAL observations from X to gamma-ray energies....
Probing the Pulsar Wind Nebula of PSR B0355+54 (2006)
McGowan, Katherine E., Vestrand, W. Tom, Kennea, Jamie A., Zane, Silvia, Cropper, Mark, Cordova, France A.
We present XMM-Newton and Chandra X-ray observations of the middle-aged radio pulsar PSR B0355+54. Our X-ray observations reveal emission not only from the pulsar itself, but also from a compact...
Zane, Silvia, Turolla, Roberto
Recent Chandra and XMM-Newton observations of a number of X-ray ``dim'' pulsating neutron stars revealed quite unexpected features in the emission from these sources. Their soft thermal spectrum,...
A Compton reflection dominated spectrum in a peculiar accreting neutron star (2005)
Rea, Nanda, Stella, Luigi, Israel, Gian Luca, Matt, Giorgio, Zane, Silvia, Segreto, Alberto, ...
We report on a puzzling event occurred during a long BeppoSAX observation of the slow-rotating binary pulsar GX 1+4. During this event, lasting about 1 day, the source X-ray flux was over a factor 10...
McGowan, Katherine E., Zane, Silvia, Cropper, Mark, Vestrand, W. Thomas, Ho, Cheng
We report on the first XMM-Newton observation of the Vela-like pulsar PSR B2334+61. Spectral analysis reveals soft X-ray emission, with the bulk of the photons emitted at energies below ~1.5 keV. We...
Schwartz, Steven J., Zane, Silvia, Wilson, Robert J., Pijpers, Frank P., Moore, Daniel R., Kataria, D. O., ...
We report here on serendipitous observations of the intense gamma-ray flare from SGR 1806-20 that occured on 27 December 2004. Unique data from the Cluster and Double Star-2 satellites, designed to...
Zane, Silvia, Turolla, Roberto
In the last few years considerable observational resources have been devoted to study the thermal emission from isolated neutron stars. Detailed XMM and Chandra observations revealed a number of...
A puzzling event during the X-ray emission of the binary system GX 1+4 (2004)
Rea, Nanda, Stella, Luigi, Israel, Gian Luca, Matt, Giorgio, Zane, Silvia, Segreto, Alberto, ...
We report on a long X-ray observation of the slow-rotating binary pulsar GX 1+4. BeppoSAX observed, in the 0.1-200 keV energy range, an event in which the source flux dropped for almost a day, and...
Timing Analysis of the Isolated Neutron Star RX J0720.4-3125 Revisited (2004)
Cropper, Mark, Haberl, Frank, Zane, Silvia, Zavlin, Vyacheslav
We present a reanalysis of the X-ray data for RX J0720.4-3125 presented in Zane et al. (2002), using more data recently available from XMM-Newton and Chandra. This analysis also corrects the Rosat...
XMM-Newton EPIC & OM observations of Her X-1 over the 35 day beat period (2004)
Zane, Silvia, Ramsay, Gavin, Jimenez-Garate, Mario A., Herder, Jan Willem Den, Hailey, Charles J.
We present the results of a series of XMM-Newton EPIC and OM observations of Her X-1, spread over a wide range of the 35 day precession period. We confirm that the spin modulation of the neutron star...
Timing analysis of the isolated neutron star RX J0720.4-3125 revisited (2004)
Cropper, Mark, Haberl, Frank, Zane, Silvia, Zavlin, Vyacheslav E.
XMM-Newton Observations of PSR B1706-44 (2003)
McGowan, Katherine E., Zane, Silvia, Cropper, Mark, Kennea, Jamie A., Cordova, France A., Ho, Cheng, ...
We report on the XMM-Newton observations of the young, 102 ms pulsar PSR B1706-44. We have found that both a blackbody plus power-law and a magnetized atmospheric model plus power-law provide an...
Bare Quark Stars or Naked Neutron Stars ? The Case of RX J1856.5-3754 (2003)
Turolla, Roberto, Zane, Silvia, Drake, Jeremy J.
In a cool neutron star (T < 1.e6 K) endowed with a rather high magnetic field (B > 1.e13 G), a phase transition may occur in the outermost layers. As a consequence the neutron star becomes `bare',...
XMM-Newton observations of the Vela pulsar (2003)
Mori, Kaya, Hailey, Charles J., Paerels, Frits, Zane, Silvia
We present spectral analysis from XMM-Newton observations of the Vela pulsar. We analyzed thermal emission from the pulsar dominating below ~ 1 keV since extracted spectra are heavily contaminated by...
Detection of Pulsed X-ray Emission from XMM-Newton Observations of PSR J0538+2817 (2003)
McGowan, Katherine E., Kennea, Jamie A., Zane, Silvia, Cordova, France A., Cropper, Mark, Ho, Cheng, ...
We report on the XMM-Newton observations of the 143 ms pulsar PSR J0538+2817. We present evidence for the first detections of pulsed X-rays from the source at a frequency which is consistent with the...
Discovery of Cyclotron Resonance Features in the Soft Gamma Repeater SGR 1806-20 (2002)
Ibrahim, Alaa I., Safi-Harb, Samar, Swank, Jean H., Parke, William, Zane, Silvia, Turolla, Roberto
We report evidence of cyclotron resonance features from the Soft Gamma Repeater SGR 1806-20 in outburst, detected with the Rossi X-ray Timing Explorer in the spectrum of a long, complex precursor...
XMM-Newton EPIC observations of Her X-1 (2002)
Ramsay, Gavin, Zane, Silvia, Jimenez-Garate, Mario, Herder, Jan-Willem Den, Hailey, C.
We present spin-resolved X-ray data of the neutron star binary Her X-1 taken using the EPIC detectors on XMM-Newton. The data were taken at three distinct epochs through the 35 day precession period....
Power-law Tails from Dynamical Comptonization in Converging Flows (2002)
Turolla, Roberto, Zane, Silvia, Titarchuk, Lev
The effects of bulk motion comptonization on the spectral formation in a converging flow onto a black hole are investigated. The problem is tackled by means of both a fully relativistic,...
Timing analysis of the isolated neutron star RX J0720.4-3125 (2002)
Zane, Silvia, Haberl, Frank, Cropper, Mark, Zavlin, Vyacheslav E., Lumb, David, Sembay, Steve, ...
We present a combined analysis of XMM-Newton, Chandra and Rosat observations of the isolated neutron star RXJ0720.4-3125, spanning a total period of \sim 7 years. We develop a maximum likelihood...
Timing study of the isolated neutron star RX J0720.4-3125 (2002)
Zane, Silvia, Haberl, Frank, Cropper, Mark, Zavlin, Vyacheslav E., Lumb, David, Sembay, Steve, ...
We present a combined analysis of XMM-Newton, Chandra and Rosat observations of the isolated neutron star RX J0720.4-3125, spanning a total period of \sim 7 years. We develop a maximum likelihood...
Timing analysis of the isolated neutron star RX J0720.4-3125 (2002)
Zane, Silvia, Haberl, Frank, Cropper, Mark, Zavlin, Vyacheslav E., Lumb, David, Sembay, Steve, ...
We present a combined analysis of XMM-Newton, Chandra and ROSAT observations of the isolated neutron star RX J0720.4-3125, spanning a total period of similar to7 yr. We develop a maximum likelihood...
First XMM-Newton observations of an isolated neutron star: RXJ0720.4-3125 (2000)
Paerels, Frits, Motch, Christian, Haberl, Frank, Zavlin, Vyacheslav E., Zane, Silvia, Ramsay, Gavin, ...
We present the high resolution spectrum of the isolated neutron star RXJ0720.4-3125, obtained with the Reflection Grating Spectrometer on XMM-Newton, complemented with the broad band spectrum...
Cropper, Mark, Zane, Silvia, Ramsay, Gavin, Haberl, Frank, Motch, Christian
We model the spin pulse intensity and hardness ratio profiles of the isolated neutron star RXJ0720.4--3125 using XMM-Newton data. The observed variation is approximately sinusoidal with a...
Isolated Neutron Stars: Accretors and Coolers (1999)
Treves, Aldo, Turolla, Roberto, Zane, Silvia, Colpi, Monica
As many as $10^9$ neutron stars populate the Galaxy, but only $\approx 10^3$ are directly observed as pulsars or as accreting sources in X-ray binaries. In principle also the accretion of the...
Old Isolated Accreting Neutron Stars: The Diffuse X--ray Emission From The Galactic Center (1996)
Zane, Silvia, Turolla, Roberto, Treves, Aldo
The contribution of weakly--magnetized ($B\sim 10^9$ G) neutron stars accreting the interstellar medium to the diffuse X--ray emission observed in the Galactic Center is investigated. It is shown...
Zane, Silvia, Turolla, Roberto, Nobili, Luciano, Erna, Myris
In this paper we present a characteristic method for solving the transfer equation in differentially moving media in a curved spacetime. The method is completely general, but its capabilities are...
Zane, Silvia, Zampieri, Luca, Turolla, Roberto, Treves, Aldo
Old isolated accreting neutron stars may show up among unidentified soft X--ray sources detected by the ROSAT All Sky Survey. We argue that the chances of identification are greater for ONSs located...
Zane, Silvia, Turolla, Roberto, Zampieri, Luca, Colpi, Monica, Treves, Aldo
The issue of the observability of Old Isolated Neutron Stars (ONSs) accreting from the interstellar gas, is reconsidered using the spectra presented in Zampieri {\it et al.\/} (1995). In particular,...
Zane, Silvia, Turolla, Roberto, Zampieri, Luca, Colpi, Monica, Treves, Aldo
The issue of the observability of Old Isolated Neutron Stars (ONSs) accreting from the interstellar gas, is reconsidered using the spectra presented in Zampieri {\it et al.\/} (1995). In particular,...
X--Ray Spectra from Neutron Stars Accreting at Low Rates (1994)
Zampieri, Luca, Turolla, Roberto, Zane, Silvia, Treves, Aldo
The spectral properties of X--ray radiation produced in a static atmosphere around a neutron star accreting at very low rates are investigated. Previous results by Alme \& Wilson (1973) are extended...