Monday 03 March 2025
A new approach has been developed to better understand the Lyman-alpha forest, a phenomenon that occurs when light passes through the intergalactic medium (IGM) and is absorbed by neutral hydrogen gas. This absorption creates a pattern of absorption lines in the spectrum of distant quasars, which can be used to study the properties of the IGM.
Traditionally, researchers have used hydrodynamic simulations to model the Lyman-alpha forest, but these simulations are computationally expensive and require significant amounts of data storage. A new method has been developed that uses a semi-analytical approach to model the Lyman-alpha forest, which is faster and more efficient than traditional methods.
The semi-analytical approach is based on the assumption that the baryonic density fields in the IGM follow a lognormal distribution. This distribution is then used to simulate the Lyman-alpha forest and predict the absorption lines that would be observed by telescopes. The simulations are compared with data from observations of quasars, which allows researchers to test the accuracy of the model.
The new approach has been tested using data from the Sherwood simulation suite, a set of high-resolution hydrodynamic simulations of the IGM. The results show that the semi-analytical approach is able to accurately reproduce the Lyman-alpha forest absorption lines, and can even be used to recover the thermal properties of the IGM.
The implications of this new approach are significant. It will allow researchers to study the Lyman-alpha forest in much greater detail than was previously possible, which could provide valuable insights into the formation and evolution of the universe. Additionally, the semi-analytical approach can be used to generate mock catalogues of quasars, which will be essential for future large-scale surveys such as the Dark Energy Spectroscopic Instrument (DESI).
The new method is also faster and more efficient than traditional hydrodynamic simulations, which means that it could be used to study the Lyman-alpha forest in much greater detail. This could include studying the properties of the IGM at high redshifts, where the universe was still in its early stages of formation.
Overall, this new approach has the potential to revolutionize our understanding of the Lyman-alpha forest and the intergalactic medium. It will allow researchers to study these phenomena in much greater detail than was previously possible, which could provide valuable insights into the formation and evolution of the universe.
Cite this article: “Unlocking the Secrets of the Lyman-Alpha Forest”, The Science Archive, 2025.
Lyman-Alpha Forest, Intergalactic Medium, Semi-Analytical Approach, Lognormal Distribution, Hydrodynamic Simulations, Quasars, Absorption Lines, Thermal Properties, Dark Energy Spectroscopic Instrument, Desi
