List of Figures

• 2.1. The 96 minute Suzaku orbit.
• 2.2. [Left] Schematic picture of the bottom of the Suzaku satellite. [Right] A side view of the instrument and telescopes on Suzaku.
• 2.3. XIS Effective area of one XRT + XIS system, for both the FI and BI chips. (No contamination included)
• 2.4. The Encircled Energy Function (EEF) showing the fractional energy within a given radius for one quadrant of the XRT-I telescopes on Suzaku at 4.5 and 8.0 keV.
• 2.5. Total effective area of the HXD detectors, PIN and GSO, as a function of energy.
• 4.1. First simulation with cornorm of the two background files put to 0.
• 4.2. Simulation with the highest possible background for both PIN and GSO.
• 4.3. Simulation with the lowest possible background for both PIN and GSO.
• 5.1. Layout of the XRTs on the Suzaku spacecraft.
• 5.2. A Suzaku X-Ray Telescope
• 5.3. A thermal shield.
• 5.4. Focal positions at the XISs when the satellite points MCG$-$6$-$30-15 at the XIS aimpoint.
• 5.5. Locations of the optical axis of each XRT-I module in the focal plane determined from the observations of the Crab nebula in 2005 August-September. This figure implies that the image on each XIS detector becomes brightest when a target star is placed at the position of the corresponding cross. The dotted circles are drawn every $30''$ in radius from the XIS-default position (see text).
• 5.6. The source- and background-integration regions overlaid on the Crab images taken with XIS1 at the XIS-default position (left) and the HXD-default position (right) on 2005 September 15-16. The images are elongated in the frame-transfer direction due to the out-of-time events (see text). In order to cancel these events, the background regions with a size of 126 by 1024 pixels each are taken at the left and right ends of the chip for the XIS-default position, and a single region with a size of 252 by 1024 pixels is taken at the side far from the Crab image for the HXD-default position. The remaining source-integration region has a size of 768 by 1024 pixels, or $13'.3\times 17'.8$. The background subtraction is carried out after after area-size correction.
• 5.7. Power-law fit to the Crab spectra of all the four XIS modules taken at the XIS-default position. All the parameters are set free to vary independently for each XIS module. The fit is carried out in the 1.0-10.0keV band but excluding the interval 1.5-2.0 keV where a large systematic error associated with the Si K-edge remains, and the other channels are retrieved after the fit.
• 5.8. Vignetting of the four XRT-I modules using the data of the Crab nebula taken during 2005 August 22-27 in the two energy bands 3-6 keV and 8-10 keV. The model curves are calculated with the ray-tracing simulator with the spectral parameters of $N_{\rm H} = 0.33\times 10^{22}$ cm$^{-2}$, photon index = 2.09, and the normalization = 9.845 photons cm$^{-2}$ s$^{-1}$ keV$^{-1}$ at 1 keV. Note that the abrupt drop of the model curves at $\sim$8$'$ is due to the source approaching the detector edge. See the text for more detail. The excess of the data points of XIS1 is probably due to insufficient calibration of the backside-illuminated CCD.
• 5.9. Image, Point-Spread Function (PSF), and EEF of the four XRT-I modules in the focal plane. All the images are binned with 2$\times$2 pixels followed by being smoothed with a Gaussian with a sigma of 3 pixels, where the pixel size is 24 $\mu$m. The EEF is normalized to unity at the edge of the CCD chip (a square of $17'.8$ on a side). With this normalization, the HPD of the XRT-I0 through I3 is $1'.8$, $2'.3$, $2'.0$, and $2'.0$, respectively.
• 5.10. Focal plane images formed by stray lights. The left and middle panels show simulated images of a monochromatic point-like source of 4.51 keV locating at $(-20', 0')$ in (DETX, DETY) in the cases of without and with the pre-collimator, respectively. The radial dark lanes are the shades of the alignment bars. The right panel is the in-flight stray image of the Crab nebula in the 2.5-5.5 keV band located at the same off-axis angle. The unit of the color scale of this panel is counts per 16 pixels over the entire exposure time of 8428.8 s. The counting rate from the whole image is 0.78$\pm$0.01 c s$^{-1}$ including background. Note that the intensity of the Crab nebula measured with XIS3 at the XIS-default position is 458$\pm$3 c s$^{-1}$ in the same 2.5-5.5 keV band. All the images are binned with 2$\times$2 pixels followed by being smoothed with a Gaussian with a sigma of 2 pixels, where the pixel size is 24 $\mu$m.
• 5.11. Angular responses of the XRT-I at 1.5 (left) and 4.5 keV (right) up to 2 degrees. The effective area is normalized at on-axis. The integration area is corresponding to the detector size of XIS ( $17'.8\times 17'.8$). The three solid lines in the plots correspond to different parameters of ray-tracing program while the crosses are the normalized effective area using the Crab pointings.
• 6.1. The four XIS detectors before installation onto Suzaku.
• 6.2. One XIS instrument. Each XIS consists of a single CCD chip with $1024 \times 1024$ X-ray sensitive cells, each 24 $\mu$m square. Suzaku contains four CCD sensors (XIS0 to 3), two AE/TCUs (AE/TCE01 and AE/TCE23), two PPUs (PPU01 and PPU23), and one MPU. AE/TCU01 and PPU01 service XIS0 and XIS1, while AE/TCE23 and PPU23 service XIS2 and XIS3. Three of the XIS CCDs are front-illuminated (FI) and one (XIS1) is back-illuminated (BI).
• 6.3. Time sequence of the exposure, frame-store transfer, CCD readout, and data transfer to the pixel RAM in PPU is shown (1) in normal mode without options, (2) in normal mode with Burst option, and (3) in normal mode with Window option. In this example, the 1/4 Window option is assumed.
• 6.4. Information sent to the telemetry is shown for $5 \times 5$, $3 \times 3$, and $2 \times 2$ modes. 1-bit information means whether or not the PH of the pixel exceeds the outer split threshold. In $2 \times 2$ mode, the central 4 pixels are selected to include the second and the third (or fourth) highest pixels among the 5 pixels in a cross centered at the event center.
• 6.5. Definition of the grades in the P-Sum/timing mode. Total pulse height and the grade of the event are output to the telemetry. Note that the grades are defined referring to the direction of the serial transfer, so the central pixel of a grade 1 event has the larger RAWX value, while the opposite is true for a grade 2 event.
• 6.6. The frame mode data of XIS2 taken with spaced-row CI. The bright lines at every 54 row correspond to the charge injected lines. The lines are disconnected because the overclocked regions are also displayed at the segment boundaries.
• 6.7. An empirical model for the on-axis contamination evolution, assuming DEHP (C24H38O4, or C/O = 6 by number) as contaminant. Crosses and open circles indicate the C column density of the contaminant derived from the E0102$-$72 and RXJ 1856 observations, respectively. Dotted lines indicate the best fit empirical model to the time evolution of the contamination for each sensor.
• 6.8. Time evolution of the radial profile of the contamination thickness derived from N and O fluorescent lines from the day earth (i.e. Sun lit Earth)) atmosphere. Each color indicates the profile at three epochs from just after ``XIS door-open'' to the recent AO1 observation. Open circles and filled triangles represent the data points determined by the N and O fluorescence lines, respectively. The best fit model is also shown in the figure. Note that, for the on-axis column densities, the results in Figure 6.7 are used.
• . The XIS background rate for each of the four XIS detectors, with prominent fluorescent lines marked. These spectra are based on $\sim\! 800$ks of observations towards the dark Earth.
• 6.10. The XIS background rate for each of the four XIS detectors, showing only energies between 0.1-2.0 keV. Below 0.3 keV the background rate for the FI chips cannot be determined due to their low effective area.
• 6.11. ACTY dependence of the NXB for XIS1 and XIS2. The NXB flux tends to be higher at larger ACTY, because some fraction of NXB is produced in the frame-store region.
• 6.12. Cut-off rigidity dependence of the NXB (average intensity in 5-10 keV) for each sensor. The NXB flux varies by a factor of $\sim$2 depending on the cut-off rigidity.)
• 6.13. The time history of the center energy of Mn K$\alpha$ from the $^{55}$Fe calibration sources for XIS0 (FI) and XIS1 (BI).
• 6.14. The time history of the energy resolution for Mn K$\alpha$ from the $^{55}$Fe calibration sources for XIS0 (FI) and XIS1 (BI).
• 6.15. The time history of the ``extra'' line width at O-K band against the pre-flight energy resolution of $60$eV in FWHM.
• 7.1. The Hard X-ray Detector before installation.
• 7.2. Schematic picture of the HXD instrument, which consists of two types of detectors: the PIN diodes located in the front of the GSO scintillator, and the scintillator itself.
• 7.3. An angular response of single fine-collimator along the satellite X-axis, obtained from offset observations on the Crab nebula.
• 7.4. [Left] A comparison of average non X-ray background spectra of PIN, measured during the first six months of the mission. The Crab spectrum scaled down with two orders of magnitude are shown together. [Right] The evolution of averaged GSO-NXB spectra during the first half year after the launch.
• 7.5. A comparison of the in-orbit detector background of PIN/GSO, averaged over 2005 August to 2006 March and normalized by individual effective areas, with those of RXTE-PCA, RXTE-HEXTE, and BeppoSAX-PDS. Dotted lines indicate 1 Crab, 100 mCrab, and 10 mCrab intensities.
• 7.6. [Left] A light curve of the non X-ray background of PIN, folded with the elapsed time after the SAA passage (top), and a plot of averaged cut-off rigidity at the corresponding position (bottom). [Right] The same folded light curves of the GSO background, in 40-90, 260-440, and 440-70 keV energy band.
• 7.7. Example of comparisons between the real data and the background model prediction of the PIN-NXB for various time bins of 1, 4, 8, 17, 32 ks, and 1 day, for one SWG observation. Earth occultation data of ten long (a few days) observations are used in the plot. The first 6 panels show the case in the energy range of 15-40 keV, while the last 6 panels do the case in the 40-70 keV. The upper figures show the comparisons of the light curves and residuals. Here the residuals represent the ratio against the total background count rate. The lower figures show the distributions of the residual (red) and the statistical error (black).
• 7.8. The same plots as the residual distributions of the PIN-NXB modeling shown in figure 7.7, but extracted from ten long observations.
• 7.9. Similar plots as figure 7.7, but for the GSO-NXB.
• 7.10. Similar to figure 7.8, but for the GSO-NXB.
• 7.11. Example of detection limit of the HXD, for continuum (left) and for line (right) detection. Solid lines stand for statistical limit, while dashed lines for an example of systematic errors, the value of which should be evaluated by the authors themselves. In the right plot, no systematic error is presented since it is very difficult to evaluate. See also figure 7.5. See text for detail on both plots.