Executive Summary for Proposal Preparation

1. The first step is to understand whether the scientific objectives are matched to the scientific capabilities of the mission (SOH sect.2 and Addendum).

2. For time constrained observation a first evaluation on the visibility of a source taking into account solar panel constraints can be found in in SOH sect. 3.

   An on-line tool useful to estimate the visibility of a source is available at the following URLs:

   • /bepposax/viewing/

   • http://heasarc.gsfc.nasa.gov/Tools/Viewing.html

   Note however that the visibility window may be substantially restricted depending on the availability of guide stars for the gyroless mode. While a final assessment must await for on-board implementation, we warn that observation of a target at a specified time, even within the constraints allowed by the solar panels, may not be feasible.

3. The next step is the evaluation of the feasibility of the proposed program with the BeppoSAX instruments. This is discussed in SOH sect. 4 (BeppoSAX Instruments) and Addendum.

   Using the expected target properties (X-ray flux, spectral shape, variability, etc.), the observer must estimate whether the scientific objectives of his/her proposal (e.g. determination of spectral shape, variability, measurement of spectral features) can be achieved and should estimate the exposure time necessary to fulfill that purpose.

   Such an assessment can be done using the tools available from the BeppoSAX SDC Web pages.

   The SSDC Web Event Simulator and On-line Analysis Service

   • /simulator/

   This tool allows proposers to simulate observations with the imaging instruments of BeppoSAX (and several other satellites). The simulated field can include both pointlike and extended sources with source positions, spectra etc. input by the user or automatically retrieved from a catalog of ROSAT sources. The output is a FITS/OGIP event file that can be analysed using standard X-ray analysis software or directly over the web using the SSDC interactive archive system.

   A WWW tool for count-rate estimation (based on the HEASARC PIMMS) is available at the following URLs:

   • /bepposax/pimms/

     http://heasarc.gsfc.nasa.gov/Tools/w3pimms.html

   Detailed spectral simulations can be performed using XSPEC, as illustrated at the following URL:

   • /bepposax/sdc_simulations.html
   In the same URL XSPEC macros are available to ease the (sometime complex) simulation procedure.

   A new Web interface to XSPEC developed by HEASARC is available at

   • http://heasarc.gsfc.nasa.gov/webspec

4. Next step is the selection of acquisition modes for each instrument. For sources fainter than about 0.3 Crab (or $\approx 10^{-8}$ erg cm$^{-2}$ s$^{-1}$, 2-10 keV), the telemetry is sufficient to support full direct modes (i.e each event is transmitted with full information) for all instruments. For such sources the proponents are encouraged to adopt the default (direct) modes. For sources brighter than 0.3 Crab the observer should find a trade-off solution, choosing the information more relevant to the scientific goal (e.g temporal vs. imaging vs. energy information), by selecting different modes or allocating the telemetry to a subset of instruments. Note that in AO5 the use of High Bit rate speed will be limited in order to reduce the stress on the Tape Recorder Unit

5. The proponents can then fill out the proposal form (see Sect. 6) retrievable via network as explained in sect. 3.2.2) following the instructions given in Sect. 3.2 and submit it according to the rules given in Sect. 4.