LST1 simulations

This service provides simulaiton of observations with Large Sizes Telescopes (LST) of the Cherenkov Telescope Array Observatory (CTAO). The spectrum simulations are created by Abelardo Moralejo, the event simulator is by Ievgen Vovk, Marcel Strzys and Elise Lagarde.

The data analysis can be launched either using the MMODA fronend interface or through a Python API from e.g. a Jupyter notebook on a user laptop. Note that the main parameter panel generic for all analysis services (specifying source name and coordinates, time interval for data selection) is currently not used in the LST1 simulation. Only the instrument-specific panel is used by the service. This panel allows to select one of the two available simulations: either a generator of Data Level 3 (DL3) events based on the pre-defined sky model, or a simulation of the expected spectrum of an astronomical source. This can be done by checking the appropriate radio button in the parameters panel:

The sky model for the event generator can be defined either specifying telescope configuration and parameters of the astronomical source in the parameter panel

or by uploading a YAML file (see example) with the definition of the sky model and telescope setup:

In the case of direct source parameter entry, the source spectrum should be defined as a function dN/dE(E), using a viable formula in python format that can contain numpy functions, such as 2.0e-10*pow(E/1000., -1.99)*exp(-E/10000), with energy in GeV. If the specified source extension is larger than zero, the source will be modelled as a Gaussian of the width given by the source extension parameter.

The "Plotting" block of parameter panel

allows to adjust parameters of visualisation of the result of simulation, which is a count map of events in a given energy range and sky pixelisation.

The spectral simulation parameter panel includes an additional "pulsar analysis" block

that allows to specify the length of the "on" and "off" pulse intervals.

Pushing the "Submit" button launches the simulation. Upon completion of the simulaiton. The progress of simulations is shown with the progress bar

that also allows to inspect the outputs of the notebook describing the simulation workflow (by clicking on the Jupyter sign to the right of the progress bar).

Upon completion of simulations, the product display panel appears. It shows a list of the data products available for inspection and download:

For the spectral simulation, five data products are generated: the counts spectrum astropy visualisation in the form of the png image, the reconstructed vs. true energy plot (also a png image), the Spectral Energy Distribution (SED) as well the astropy tables with the count spectrum and SED.

For the event generator, the data products include event files for each simulating pointing as well as visualisation of the simulated sky countmap:

In each case, the "Query parameters" button provides the metadata with the analysis parameters. The "API code" button displays the Python API code that can be copy-pasted into a python code (e.g. on the user laptop) to request the data product. Finally, the Jupyter icon provides visualisation of the Python notebook used in the analysis.