1. Introduction

Suzaku, formerly Astro-E2, is the fifth Japanese X-ray astronomy satellite built by the Institute of Space and Astronautical Sciences of Japan Aerospace Exploration Agency (ISAS/JAXA). It was launched from the Uchinoura Space Center (USC) on 2005 July 10. Suzaku is the second ISAS X-ray astronomy satellite built in close collaboration with National Aeronautics and Space Administration's Goddard Space Flight Center (NASA/GSFC).

1.1 Scope of this Document

This document covers the following:

• An brief overview of the mission, the instruments on-board, and the Suzaku Guest Observer Facility (GOF).
• An overview of the end-to-end flow of data, from the satellite to the user and the archive, and the division of labor between ISAS/JAXA and NASA/GSFC, as well as that among groups within NASA/GSFC.
• The Suzaku data and data products.
• The support given to guest observers (GOs)

This document is not the original source for:

• High level agreements between ISAS/JAXA and NASA/GSFC, such as the allocation of observing time.
• Detailed technical information about the instruments, including design and calibration.
• Technical information about the telemetry.

In chapter 2, Suzaku operation and types of observations are briefly explained. Suzaku software design principles and agreements are presented in chapter 3. Further details of software are described in chapters 4, 5, and 6. Important issues regarding the calibration are given in chapter 7. Tasks regarding the Guest Observer support are shown in chapter 8, and Suzaku archives are explained in chapter 9.

In appendix A, acronyms used in this document are defined. Guidelines for FTOOLS developers are described in appendix B. A flow chart of the pipe-line processing is displayed in appendix C. Coordinate system of each detector is listed in appendix D.

1.2 Mission Overview

Suzaku was launched with three types of instruments on-board, covering a wide range of energies. The X-Ray Spectrometer (XRS) is the first micro-calorimeter based X-ray instrument to be launched into orbit. Although it prematurely lost all its cryogen shortly after launch and therefore stopped operation before it could obtain astronomically useful data, the XRS had an excellent energy resolution ($\Delta E \sim$ 6-7 eV) over its 0.3-12 keV bandpass.

The 4 units of X-ray Imaging Spectrometers (XISs) are CCD cameras, providing moderate spectral resolution over 0.2-12 keV ( $\Delta E \sim 130$ eV at 6 keV). There are five X-Ray Telescopes (XRTs) on-board Suzaku, one in front of the XRS and the other four in front of the XISs, providing high throughput and modest spatial resolution. The field of view (FOV) of XRT + XIS is 19$' \times$19$'$ with a spatial resolution of about 2$'$ half-power diameter (HPD).

The Hard X-ray Detector (HXD) is a non-imaging, collimated instrument that covers the energy band $\sim$10-700 keV using two types of detectors, PIN (10-60 keV) and GSO (50-700 keV). The full width at half maximum (FWHM) spectral resolution is 3 keV for the PIN detector and $\sim$ 10 % at 600 keV for the GSO detector. The innovative design of the HXD results in low background and, hence, high sensitivity.

All instruments operate simultaneously and are co-aligned, so that a given target can be observed over 0.2-700 keV at high sensitivity and with good spectral resolution. This makes Suzaku a powerful observatory for a wide range of astronomical objects. In addition, the background detectors of the HXD can be used to monitor a wide area of the sky.

1.3 The Suzaku Guest Observer Facility

The Suzaku Guest Observer Facility (GOF) is located at NASA's GSFC within the Office of General Investigator Programs (OGIP). Besides the Suzaku GOF, OGIP contains the High Energy Astrophysical Science Archive Research Center (HEASARC) and GOFs for other major high energy missions. The HEASARC is a data center responsible for archiving data from past high energy astrophysical missions and constructing a user-friendly data analysis environment. Suzaku GOF carries out its tasks in collaboration with HEASARC.

The GOF is responsible for the US Guest Observer support, including:

• Support of prospective GOs' proposal preparation

• Support of US peer-reviews of GO proposals.

• Receiving, validating, processing, archiving and distributing the data, in collaboration with the HEASARC.

• Providing documentations and on-online materials

• Providing expert help to GOs

Suzaku GOF WWW home page is located at

http://heasarc.gsfc.nasa.gov/docs/suzaku/.

1.4 Related Documents

Other important issues which cannot be covered in this document described elsewhere, including:

• The Suzaku Technical Description -- Design of the entire satellite, instruments, and their specification. This is available at
  http://heasarc.gsfc.nasa.gov/docs/suzaku/docs/suzaku/prop_tools/suzaku_td/

• Suzaku FITS File Formats -- FITS formats of the Suzaku HK and event files, calibration files and other important files (e.g., attitude files and orbit files)

• Suzaku Interface Control Document (ICD) -- it defines the interface between Suzaku processing processing systems and the HEASARC, and contains the directory structure and file name convention for files that are delivered.

• Suzaku Calibration -- How Suzaku instruments and data are calibrated is explained. See 7.1 for details.

• Suzaku data analysis guide (also known as the ABC Guide) -- Provides an overview of Suzaku data analysis. This document will be available at
  http://heasarc.gsfc.nasa.gov/docs/suzaku/docs/suzaku/analysis/suzaku_abc/