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Gravitational Lensing Simulation

This script simulates a gravitational lensing effect using the Lenstronomy package. Gravitational lensing is a phenomenon predicted by Einstein's theory of General Relativity where light from a distant source is bent by the gravitational field of a massive object, such as a galaxy or a cluster of galaxies.

Dependencies

Make sure you have the following Python libraries installed:

• numpy
• lenstronomy
• matplotlib

You can install them using pip:

pip install numpy lenstronomy matplotlib

Overview

This script simulates the lensing effect caused by a point mass, using the Lenstronomy package. It creates a simulated lensed image of a point source (star or quasar) that is gravitationally lensed by a massive object acting as a gravitational lens.

Simulation Process

1. Lensing Parameters:

   • The script defines the mass of the lens and the distance to the source.
   • It converts the lens mass from kilograms to solar masses and the source distance from parsecs to arcseconds.

2. Lens Model:

   • The lens model is defined using a point mass.

3. Source Setup:

   • A lensed point source is set up at the position where lensing occurs.

4. PSF and Image Data Setup:

   • The script sets up a Gaussian PSF and creates a blank image with specified pixel and coordinate details.

5. Image Model:

   • Components (image data, PSF, lens model, and point source) are combined to form an image model.

6. Image Simulation:

   • A lensed image is simulated based on the lens model and point source parameters.

Parameters

• Lens Mass: Mass of the lensing object in kilograms, converted to solar masses.
• Source Distance: Distance to the source in parsecs, converted to angular distance in arcseconds.
• PSF FWHM: Full Width at Half Maximum (FWHM) of the Gaussian PSF in arcseconds.
• Image Size: Number of pixels in the simulated image.
• Pixel Coordinates: RA and DEC coordinates at the position of the pixel edge.
• Transform Matrix: Linear translation matrix for converting pixel shifts to angular shifts.

Running the Code

1. Clone the repository:

   git clone https://github.com/the-w00d/Specific-Test-VII.-Expanding-Strong-Gravitational-Lensing-Simulations.git
   cd Specific-Test-VII.-Expanding-Strong-Gravitational-Lensing-Simulations-main

2. Run the script:

   Strong Gravitational Lensing Simulations.ipynb

3. View Results:

   • The script will generate a simulated lensed image and display it using Matplotlib.

Example Output

The simulated lensed image will demonstrate the gravitational lensing effect on the point source due to the lensing object's mass.

References

• Lenstronomy documentation: Lenstronomy GitHub
• Gravitational lensing: Wikipedia - Gravitational lens

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Author

• Dawood Khan
• GitHub: @the-w00d
• linkden: @Dawoodkhan

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