All Figures

$\begin{figure} \par\includegraphics[height=7.6cm,width=3.6cm,angle=270,clip]{839... ...ludegraphics[height=7.6cm,width=3.6cm,angle=270,clip]{8399fig1d.eps}\end{figure}$ Figure 1: A selection of GRB lightcurves detected by the Anti-Coincidence Shield at photon energies >80 keV.
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In the text

$\begin{figure} \par\includegraphics[height=7.6cm,width=4cm,angle=270,clip]{8399f... ...includegraphics[height=7.6cm,width=4cm,angle=270,clip]{8399fig2c.ps}\end{figure}$ Figure 2: a) Raw and b) denoised lightcurves of GRB 070615 in the 25-50 keV (dark line) and 50-300 keV (light line) energy bands. c) Cross correlation functions and polynomial fits giving a lag of 0.40^+0.15_-0.25 and 0.40^+0.15_-0.20 for the raw and denoised lightcurve data, respectively. The dashed line represents a lag of 0 s.
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In the text

$\begin{figure} \par\includegraphics[height=4.6cm,width=7.4cm,clip]{8399fig3a.eps... ...{2mm} \includegraphics[height=4.6cm,width=7.4cm,clip]{8399fig3b.eps}\end{figure}$ Figure 3: a) INTEGRAL exposure map in galactic coordinates from October 2002 up to July 2007 (contours in units of kiloseconds), showing the concentration of exposure in the direction of the galactic plane (Erik Kuulkers, private communication). b) Spatial distribution of 47 INTEGRAL GRBs detected between October 2002 and July 2007 in galactic coordinates.
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In the text

$\begin{figure} \par\includegraphics[angle=270,width=8cm,clip]{8399fig4.eps}\end{figure}$ Figure 4: The off-axis angle distribution of the GRBs in the IBIS FoV as a function of peak flux (20-200 keV). The FCFoV is $9^{\circ }$ $\times$ $9^{\circ }$ and the boundary of the PCFoV is between $4.5^{\circ }$ and $6.2^{\circ }$ , depending on the azimuthal angle of the GRB position. The long-lag GRBs are marked with filled diamonds. There are 11 GRBs within the FCFoV and 4 have long lags. IBIS is less sensitive to $\gamma$ -ray sources outside the FCFoV as reflected by the decrease in the number of faint GRBs.
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In the text

$\begin{figure} \par\includegraphics[angle=270,width=7.3cm,clip]{8399fig5.eps}\end{figure}$ Figure 5: The cumulative log N-log P distribution of the 47 GRBs detected by IBIS, with peak flux P measured between 20-200 keV. The distribution is biased by the lower sensitivity of IBIS at large off-axis angles (Fig. 4). The small subset of 11 long-lag GRBs is shown separately.
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In the text

$\begin{figure} \par\includegraphics[height=5.3cm,width=7.2cm,clip]{8399fig6.ps}\end{figure}$ Figure 6: T₉₀ distribution of INTEGRAL GRBs (solid line) in comparison to that of BATSE (dashed line). The BATSE distribution is normalised to the peak of the INTEGRAL distribution for clarity. The BATSE data for 2041 GRBs is taken from the Current Catalog at http://www.batse.msfc.nasa.gov/batse/grb/catalog/current.
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In the text

$\begin{figure} \par\includegraphics[height=8cm,width=4.15cm,angle=270,clip]{8399... ...cludegraphics[height=8cm,width=4.15cm,angle=270,clip]{8399fig7c.eps}\end{figure}$ Figure 7: a) IBIS ${\nu }$ $F_{\nu }$ power-law spectrum of GRB 060114 in the 20-800 keV energy range. b) IBIS ${\nu }$ $F_{\nu }$ spectrum of GRB 061025, fit by the quasithermal (blackbody + power-law) model in the 20-800 keV energy range. c) SPI ${\nu }$ $F_{\nu }$ spectrum of GRB 050525a, from 20 keV-8 MeV, fit with the Band model.
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In the text

$\begin{figure} \par\includegraphics[width=7.2cm,clip]{8399fig8.ps}\end{figure}$ Figure 8: Power-law photon index distribution for INTEGRAL GRBs detected between October 2002 and July 2007 (solid line) and Swift GRBs detected between November 2004 and July 2007 (dashed line), in the 20-200 keV and 15-150 keV energy bands, respectively. The Swift data for 238 GRBs is taken from http://swift.gsfc.nasa.gov/docs/swift/archive/grb_table.html.
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In the text

$\begin{figure} \par\includegraphics[width=7.2cm,clip]{8399fig9.ps}\end{figure}$ Figure 9: Peak flux distribution for GRBs detected by INTEGRAL (20-200 keV, solid line) and Swift (15-150 keV, dashed line). The Swift data for 237 GRBs is taken from http://swift.gsfc.nasa.gov/docs/swift/archive/grb_table.html.
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In the text

$\begin{figure} \par\includegraphics[width=7.2cm,clip]{8399fig10.ps}\end{figure}$ Figure 10: Spectral lag distribution for the 28 INTEGRAL GRBs for which a lag could be measured between 25-50 keV and 50-300 keV ( $\tau _{2+3,1}$ ). The distribution is separated by the dashed line into short-lag and long-lag GRBs at $\tau_{2+3,1}=0.75~{\rm s}$ .
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In the text

$\begin{figure} \par\includegraphics[angle=270,width=7.9cm,clip]{8399fig11.ps}\end{figure}$ Figure 11: Spectral lag distribution of INTEGRAL GRBs as a function of peak flux (20-200 keV). The SN bursts GRB 980425 and GRB 031203 are identified and represented by open circles, as is GRB 060505 which does not have an associated SN. XRF 060218 has a peak flux of $0.6~{\rm ph}~{\rm cm}^{-2}~{\rm s}^{-1}$ and is not included in the figure because of its very long lag of 61 $\pm$ 26 s. GRBs with the longest lags tend to have low peak fluxes, whereas GRBs with short lags have both low and high peak fluxes. The dashed line indicates the separation between long and short-lag GRBs at $\tau _{2+3,1}=0.75$ s.
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In the text

$\begin{figure} \par\includegraphics[angle=270,width=8.1cm,clip]{8399fig12.eps}\end{figure}$ Figure 12: Isotropic peak luminosity ( $\times$ $10^{51}~{\rm erg}~{\rm s}^{-1}$ , 50-300 keV) as a function of spectral lag measured between 25-50 keV and 100-300 keV. The two exceptions are GRB 060505 and GRB 060614 for which the lag was measured between 25-50 keV and 50-100 keV and 15-25 keV and 50-100 keV, respectively. The dashed line is the anti-correlation obtained for 6 bursts (diamonds) at known redshift (Norris et al. 2000). The 3 INTEGRAL GRBs with a redshift and measured lag are represented by open circles, including the SN burst GRB 031203. The other low-luminosity SN bursts GRB 980425 and XRF 060218 are identified and represented by squares and the two GRBs without SNe by filled circles. The long-lag GRBs lie within the dashed box if they are at the adopted distance of 250 Mpc, with peak luminosities ranging from 6 $\times$ 10⁴⁶ to 1.4 $\times$ $10^{48}~{\rm erg}~{\rm s}^{-1}$ and total luminosities from 10⁴⁸ to $10^{50}~{\rm erg}$ . The solid line is the proposed lag-luminosity relationship for the low-luminosity GRBs and extrapolates to short GRBs at low values of the lag, e.g. GRB 060614, which lies in the region of the plot occupied by short GRBs. No k-correction was applied to the data.
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In the text

$\begin{figure} \par\includegraphics[height=4.6cm,width=7.4cm,clip]{8399fig13a.eps}\par\includegraphics[height=4.6cm,width=7.4cm,clip]{8399fig13b.eps}\end{figure}$ Figure 13: a) INTEGRAL exposure map in supergalactic co-ordinates up to July 2007 (contours in units of kiloseconds). b) The distribution of INTEGRAL GRBs in supergalactic co-ordinates; the open circles represent short-lag GRBs ( $\tau _{2+3,1}<0.75$ s) and filled-in circles those GRBs with long lags ( $\tau _{2+3,1}>0.75$ s). The 16 GRBs for which a lag could not be determined are denoted by an ``x'', as are the XRFs which do not have a measured lag between 25-50 keV and 50-300 keV, and the short burst GRB 070707. Ten out of the 11 long-lag GRBs are within $\pm$ $30^\circ$ of the supergalactic plane.
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In the text

$\begin{figure} \par\mbox{ \subfigure{\includegraphics[height=0.35\textheight,wid... ...t=0.35\textheight,width=0.18\textwidth,angle=270]{8399ap12.eps} } } \end{figure}$ Figure A.1: Lightcurves of GRBS observed with INTEGRAL.
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In the text

$\begin{figure} \par\mbox{ \subfigure{\includegraphics[height=0.35\textheight, w... ...t=0.35\textheight,width=0.18\textwidth,angle=270]{8399ap24.eps} } } \end{figure}$ Figure A.1: continued.
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In the text

$\begin{figure} \par\mbox{ \subfigure{\includegraphics[height=0.35\textheight, wi... ...t=0.35\textheight,width=0.18\textwidth,angle=270]{8399ap36.eps} } } \end{figure}$ Figure A.1: continued.
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In the text

$\begin{figure} \par\mbox{ \subfigure{\includegraphics[height=0.35\textheight, wi... ...ght=0.35\textheight,width=0.18\textwidth,angle=270]{8399ap43.eps} } \end{figure}$ Figure A.1: continued.
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In the text

$\begin{figure} \par\includegraphics[height=7.6cm,width=3.6cm,angle=270,clip]{839... ...ludegraphics[height=7.6cm,width=3.6cm,angle=270,clip]{8399fig1d.eps}\end{figure}$	Figure 1: A selection of GRB lightcurves detected by the Anti-Coincidence Shield at photon energies >80 keV.
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$\begin{figure} \par\includegraphics[height=7.6cm,width=4cm,angle=270,clip]{8399f... ...includegraphics[height=7.6cm,width=4cm,angle=270,clip]{8399fig2c.ps}\end{figure}$	Figure 2: a) Raw and b) denoised lightcurves of GRB 070615 in the 25-50 keV (dark line) and 50-300 keV (light line) energy bands. c) Cross correlation functions and polynomial fits giving a lag of 0.40^+0.15_-0.25 and 0.40^+0.15_-0.20 for the raw and denoised lightcurve data, respectively. The dashed line represents a lag of 0 s.
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$\begin{figure} \par\includegraphics[height=4.6cm,width=7.4cm,clip]{8399fig3a.eps... ...{2mm} \includegraphics[height=4.6cm,width=7.4cm,clip]{8399fig3b.eps}\end{figure}$	Figure 3: a) INTEGRAL exposure map in galactic coordinates from October 2002 up to July 2007 (contours in units of kiloseconds), showing the concentration of exposure in the direction of the galactic plane (Erik Kuulkers, private communication). b) Spatial distribution of 47 INTEGRAL GRBs detected between October 2002 and July 2007 in galactic coordinates.
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$\begin{figure} \par\includegraphics[angle=270,width=7.3cm,clip]{8399fig5.eps}\end{figure}$	Figure 5: The cumulative log N-log P distribution of the 47 GRBs detected by IBIS, with peak flux P measured between 20-200 keV. The distribution is biased by the lower sensitivity of IBIS at large off-axis angles (Fig. 4). The small subset of 11 long-lag GRBs is shown separately.
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$\begin{figure} \par\includegraphics[height=5.3cm,width=7.2cm,clip]{8399fig6.ps}\end{figure}$	Figure 6: T₉₀ distribution of INTEGRAL GRBs (solid line) in comparison to that of BATSE (dashed line). The BATSE distribution is normalised to the peak of the INTEGRAL distribution for clarity. The BATSE data for 2041 GRBs is taken from the Current Catalog at http://www.batse.msfc.nasa.gov/batse/grb/catalog/current.
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$\begin{figure} \par\includegraphics[height=8cm,width=4.15cm,angle=270,clip]{8399... ...cludegraphics[height=8cm,width=4.15cm,angle=270,clip]{8399fig7c.eps}\end{figure}$	Figure 7: a) IBIS ${\nu }$ $F_{\nu }$ power-law spectrum of GRB 060114 in the 20-800 keV energy range. b) IBIS ${\nu }$ $F_{\nu }$ spectrum of GRB 061025, fit by the quasithermal (blackbody + power-law) model in the 20-800 keV energy range. c) SPI ${\nu }$ $F_{\nu }$ spectrum of GRB 050525a, from 20 keV-8 MeV, fit with the Band model.
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$\begin{figure} \par\includegraphics[width=7.2cm,clip]{8399fig8.ps}\end{figure}$	Figure 8: Power-law photon index distribution for INTEGRAL GRBs detected between October 2002 and July 2007 (solid line) and Swift GRBs detected between November 2004 and July 2007 (dashed line), in the 20-200 keV and 15-150 keV energy bands, respectively. The Swift data for 238 GRBs is taken from http://swift.gsfc.nasa.gov/docs/swift/archive/grb_table.html.
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$\begin{figure} \par\includegraphics[width=7.2cm,clip]{8399fig9.ps}\end{figure}$	Figure 9: Peak flux distribution for GRBs detected by INTEGRAL (20-200 keV, solid line) and Swift (15-150 keV, dashed line). The Swift data for 237 GRBs is taken from http://swift.gsfc.nasa.gov/docs/swift/archive/grb_table.html.
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$\begin{figure} \par\includegraphics[width=7.2cm,clip]{8399fig10.ps}\end{figure}$	Figure 10: Spectral lag distribution for the 28 INTEGRAL GRBs for which a lag could be measured between 25-50 keV and 50-300 keV ( $\tau _{2+3,1}$ ). The distribution is separated by the dashed line into short-lag and long-lag GRBs at $\tau_{2+3,1}=0.75~{\rm s}$ .
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$\begin{figure} \par\mbox{ \subfigure{\includegraphics[height=0.35\textheight,wid... ...t=0.35\textheight,width=0.18\textwidth,angle=270]{8399ap12.eps} } } \end{figure}$	Figure A.1: Lightcurves of GRBS observed with INTEGRAL.
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$\begin{figure} \par\mbox{ \subfigure{\includegraphics[height=0.35\textheight, w... ...t=0.35\textheight,width=0.18\textwidth,angle=270]{8399ap24.eps} } } \end{figure}$	Figure A.1: continued.
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