AliXCatDB Tutorial

AliXCatDB is a tool developed by the Survey Science Center (SSC) of the XMM-Newton satellite at the University of Strasbourg. It serves as an interface for exploring and analyzing data from the XMM-Newton X-ray observatory, particularly focusing on the 4XMM catalog of X-ray sources. This tool allows users to visualize X-ray sources, access detailed information about individual detections, and perform various analyses.

This tutorial provides step-by-step instructions to help users effectively utilize AliXCatDB. It covers functionalities such as opening the tool at a specific position, editing regions, changing surveys, and displaying catalogs.

Opening the tool at a specific position: Users can launch AliXCatDB at a predefined sky position to quickly access relevant data.

Editing regions: The tutorial explains how to modify selected regions within the tool to refine searches and analyses.

Changing surveys: Users can switch between different astronomical surveys to compare data from various observations.

Displaying catalogs: The guide details how to load and visualize different catalogs to explore available sources and metadata.

🛰 Opening a Given Position with AliXCatDB

AliXCatDB allows you to access a specific position using various methods, including Object Name, srcid, iauname, obsid, or position coordinates. Below, we will show examples of how to use different methods.

🎯 By Target Name
- Click on the target icon and enter the source name in the window.
- Example: GX 339-4
- The application will automatically locate the source and display a popup with its parameters.
- A message at the top will confirm the selection:
- You can cross-check the source coordinates in the top-left window.
🔭 By XMM Observation ID
- Enter an Observation ID in the search window to open a specific observation.
- Example: 0800731401
🔎 By XMM Detection ID
- Enter a Detection ID in the search window to open a specific detection.
- Example: 208007307010047
🔎 By iauname
- Enter a iauname in the search window to open a specific detection.
- Example: 4XMM J004044.4+422435
🔎 By Position Coordinates
- Enter position coordinates (RA DEC separated by space) in the search window to open a specific detection.
- Example: 10.111733 42.257366

🌐 Alternative Access via URL

For quick access, you can also directly modify the URL for the same examples provided above:

🔹 By Target Name: https://xcatdb.unistra.fr/alixcatdb/?target=GX339-4
🔹 By XMM Observation ID: https://xcatdb.unistra.fr/alixcatdb/?target=0800731401
🔹 By XMM Detection ID: https://xcatdb.unistra.fr/alixcatdb/?target=208007314010023
🔹 By IAU Name: https://xcatdb.unistra.fr/alixcatdb/?target=4XMM J004044.4+422435
🔹 By Position Coordinates: https://xcatdb.unistra.fr/alixcatdb/?target=10.111733 42.257366

🌌Display XMM Source Catalogue for a Given Region

This tutorial explains how to visualize and analyze XMM sources in a specific region using various tools and filtering options.

🔎 Preview XMM Sources

Hover over the XMM 👁️ (Preview icon) button and it will display a message:

➡️ "Show XMM source in a 1 arcmin cone centered on the view."

(Example shown below)
Once you click on the Preview icon, it will turn red. This will display all the sources observed with XMM in the selected region.

🌠 Viewing Source Details

Clicking on any source region will open a window with detailed source parameters, including:
- iauname – Source name
- srcid – Source ID
- Ra, Dec – Right Ascension and Declination
- var_flag – Variability flag
- confused – Confusion flag
- Sum flag – Summary flag
- first obs, last obs – First and last observation date
- nb_detec – Number of detections
- extent, extent_ml – Extent and extent ML
- ep_1_flux - ep_8_flux – Flux in different energy bands:
- HR1 - HR4 – Hardness ratios

For more details, see the XMM User Guide.

🎯 Filtering Sources

You can filter sources using parameters such as:
- Source Name: Example - 4XMM J174805.1-244646
- Variable: True or False
- Confused: True or False
- Summary Flag: Range 0-4
- srcid: Specific Source ID
- mjd_first, mjd_last: Observation date range
- Number of Detections: 0-100
- Extent: 0-100
- ep_1_flux - ep_8_flux: Flux in different bands
- HR1 - HR4: Hardness ratios (-1 to 1)

Example: Filtering for 4XMM J174805.1-244646 shows only this source after applying the filter.

📊 Source Information Window

Clicking on the source displays a window with its parameter details.

🚀 How to Change Surveys

In this section, we will explore how to change the displayed survey by selecting different options from the Survey Panel.

Open the Survey Panel: This will display a list of available surveys that you can choose from.

Survey List Appears: A window will appear with all the matching HiPS surveys.

View Survey Details: Click on the survey title to see a description of the selected survey.

Selecting a Survey: For example, selecting X-ray images on band 2-4.5KeV | xcatdb/P/XMM/PN/eb4 will display its details.

Example of the displayed output:

Zooming out for a wider view:

Other available surveys include:
- Rp flux map for table I/355/gaiadr3 (Gaia DR3)
- Gaia DR3 radial velocity map

Search for an Interesting Survey: Browse and explore different surveys to find the most relevant data.

✏️ How to Use the Region Tool

This section explains how to define and analyze specific regions using the Region Tool in AliXCatDB.

Open the Region Panel

Click on the "Analyse" button to access the region selection tool.

Edit the Region

Click "Edit" to modify or create a new selection.

Choose a Region Type

You can select from the following options:
- Polygon
- Circle – Use the switch button to select this option.

Confirm Your Selection

Once a polygon is closed or a circle is drawn, click "Accept."

Process the Region

The selected region appears in Aladin. Click the "Process" button to analyze the region using the Amora Service.

Select the Camera

In the Amora Service, hover over the "Observation Selector" to choose between the available cameras:
- EMOS-1
- EMOS-2
- EPN

Choose the Process Control Option

Available options include:
- Preview image
- Generate multiple previews
- Generate polygons for observations
- Generate spectra
- Generate time series
- Generate light curves
- Try new parameters

Example: Generating Spectra

Select the "Generate Spectra" option to analyze spectral data.

Start the Processing

Choose the observations and initiate the process. The terminal will show the status of the running task.

Previews

The preview dropdown menu allows users to preview spectra and light curves.

Data

The data dropdown menu allows users to download data.

📊 How to Use XCatDB for Analysis

🔍 Select the target of your choice using Object Name, srcid, iauname, obsid, or position name.
📜 A window will appear containing the parameter information.
🖥️ At the bottom of the window, five clickable icons will appear:
1) ESA 2) IRAP 3) CDS 4) ACDS 5) XCatDB
➡️ Click on the XCatDB icon to open a new window with all data related to the selected source with detections.
🛠️ The page provides five buttons: 1) ADCS Sources 2) SED(s) 3) Details 4) Gallery 5) Graphs
📈 Viewing the SED(s) (if available):
ℹ️ Checking the Details of the source:
🖼️ Clicking on the Gallery button displays all light curves and spectra.

If you click on the right arrow below the spectra (M1, M2 and PN), a pop-up window will appear with five options:
- 1. Link EObsSpecToSpecPlot (Preview)
- 2. Link zipball (Data)
- 3. Link phabsPow (Preview)
- 4. Link zphabsPow (Preview)
- 5. Link phaMekal (Preview)
Selecting EObsSpecToSpecPlot (Preview) shows the background-subtracted spectra:
📂 You can download ZIP files by clicking on Link zipball (Data). This ZIP folder contains raw spectrum with all the ancillary files required to fit it in the xspec.
📊 Next, we fit the spectra using the phabsPow (Preview) option.
Settings: Bin value = 10, nH Galactic = 0.2 × 10²² cm^-2, Alpha = 2.6.
Submit the query.

The output will be:

You can use other models in a similar way to fit the spectra interactively. The interface also allows users to download the product files.
📉 The Graph button shows the hardness ratio plots for all instruments (MOS1, MOS2, EPIC, and PN) in all detections, including a merged point.