INVITE - INTEGRAL visualisation tool and explorer

The underlying libraries have been tested on the following platforms:

• Windows 2000/XP
• Solaris
• Linux
• Mac OS X

The INtegral VIsualisation Tool and Explorer (INVITE) provides an easy and convenient method of manipulating light-curves from INTEGRAL and many other instruments. It is intended as a quick look facility. The results obtained will not be optimum and are not a substitute for a full analysis using OSA.

INVITE allows the combination of light-curve data from adjacent energy bands from a given instrument.

To combine the light-curves:

1. Select the corresponding checkboxes in the combine-column of the information table and push the combine button on the toolbar. Only adjacent energy ranges can be combined.
2. The unbinned count rates from the selected energy bands are added up. The error is calculated as the square root of the quadratic sum of the individual unbinned errors.
3. The combined light-curve data is added in the information table and the corresponding light-curve is displayed. The data is binned in time with the bin time specified on the toolbar.

A ratio of light-curves in different bands for a given instrument can be generated in the following way:

1. Push the Hardness-Ratio button on the toolbar to make a pop-up window appear where you can specify the hardness-ratio definition and the energy bands for generating this ratio.
2. After pushing the OK button, the unbinned count rates of the ratio are divided and a propagated error on this ratio is calculated. The corresponding hardness-ratio is displayed and binned with the time specified on the toolbar.

Displaying the parent light-curves of a hardness-ratio.

To display the parent light-curves, simply press the display button on the toolbar of the hardness-ratio chart.

To bin the light-curve and/or hardness-ratio data in time:

1. Specify the number of seconds in the field on the toolbar and push the bin button.
2. For all light-curve and hardness-ratio data, a weighted mean is calculated if the time between two succesive data points is less then the specified bin time.

If a number of light-curves covering adjacent bands are available, these can be used to generate a broad-band spectrum for a period of interest.

To generate the spectrum:

1. Select a period of interest from either the light-curve or the hardness-ratio plot using the cursor and push the spectrum button on the toolbar.
2. For the time period currently visible in the window, a spectrum is generated using a weighted mean of the adjacent energy bands.

Launching Xspec

Once a spectrum is generated, it can be passed to Xspec¹ to perform a more detailed spectral analysis. This can be done by simply pushing the Xspec button on the toolbar of the spectrum plot. In order to run from INVITE, Xspec needs to be installed on the local class path.

An image meta data query can be executed using the Virtual Observatory (VO). This is done by making a connection with the INTEGRAL Science Data Archive (ISDA) using the Archive Inter Operability system (AIO).

To obtain the image meta data:

1. Select a period of interest from either the light-curve or the hardness-ratio plot using the cursor and push the image button on the toolbar.
2. For the time period currently visible in the window, all available image meta data is displayed in the image dialog. This meta data consists of:
   1. an Observation Data Set IDentifier (ODS ID)
   2. the start and end time of this ODS

Launching DS9

Once the image meta data is available, images can be displayed and manipulated with DS9¹. This can be done by checking the corresponding checkboxes in the image dialog and pushing the run button on the toolbar of the image dialog. In order to run from INVITE, DS9 needs to be installed on the local class path.

Pieter-Jan Baeck