Introduction
============

This section describes the data products for the SIM level-1 VIS, NISP-S and NISP-P. 

In the `SIM Splitted pipeline <https://gitlab.euclid-sgs.uk/PF-SIM/sim_ial_pipelines/-/tree/develop/SIM_IAL_Pipelines/auxdir/SIM_Pipelines/SIM_SplittedPipeline>`_, the focal plane simulation is split per detector. Every simulator :term:`Processing Function` implements 3 :term:`Processing Element` with suffixes 

* `Split` to split the catalogues, and produce detector specific internal configuration files
* `Detector` to simulate a detector image
* `Combine` to combine the detector images and metadata into a LE1 data product

In addition, there is a :term:`Processing Element` without a suffix, that simulates all the detectors at once.

Depending on the simulator, the input data products are

* :ref:`SIMVisInputConfiguration`
* :ref:`SIMNipInputConfiguration`
* :ref:`SIMNisInputConfiguration`
* :ref:`SIMExtInputConfiguration`

In addition, all simulators ingest the following data products

* :ref:`SIMTrueUniverseOutput` with the metadata and link to the galaxy, star and SSO catalogues
* :term:`Mission Data Base` with the telescope and instrument model, environment data

All simulators produce a focal plane image split per detector in a
multi-extension FITS file.  The output data products are 

* :ref:`LE1VisRawFrame` for VIS
* :ref:`LE1NispRawFrame` for NIS and NIP