Lyman alpha forest different for different objects?

In summary, the conversation discusses the distribution of Lyman alpha absorbers in a quasar spectrum and how it varies with red-shift and the age of the universe. It is mentioned that the frequency of absorbers follows a power law, but the constants involved and the distribution of absorption systems vary for different objects. The speaker is looking for a recent reference on this topic.
  • #1
Jonathan Scott
Gold Member
2,340
1,149
I was wondering how the distribution of Lyman alpha absorbers (as seen in the "forest" of absorption lines of a quasar spectrum) varies with red-shift (corresponding to evolution with the age of the universe). I've found various sources which mention in passing that the frequency of absorbers in a given spectrum vary with redshift according to a power law, which sounds interesting.

But it seems that the constants involved and hence the redshift distribution of absorption systems varies for different objects. Is that really right, and if so how can that be? I had expected that the average number of clouds between two given redshift values would be about the same in all directions, so all objects should show similar distributions.

Can anyone point me to a recent reference on this? Most of the papers I can find are around 1997-2001.
 
Astronomy news on Phys.org

1. What is the Lyman alpha forest?

The Lyman alpha forest is a phenomenon observed in the spectra of distant objects in space, such as galaxies and quasars. It appears as a series of absorption lines at specific wavelengths in the ultraviolet range.

2. Why does the Lyman alpha forest appear different for different objects?

The Lyman alpha forest is caused by the absorption of light from neutral hydrogen gas in the intergalactic medium. As light from distant objects travels through this gas, the gas absorbs specific wavelengths, creating the absorption lines. The appearance of the Lyman alpha forest varies because the amount and distribution of this gas is different for each object.

3. How can we use the Lyman alpha forest to study the intergalactic medium?

By analyzing the absorption lines in the Lyman alpha forest, we can learn about the properties of the gas, such as its density, temperature, and chemical composition. This provides valuable information about the intergalactic medium and its role in the formation and evolution of galaxies.

4. Are there any other factors that can affect the appearance of the Lyman alpha forest?

Yes, in addition to the intergalactic medium, the Lyman alpha forest can also be affected by other factors such as the distance of the object, the orientation of the gas, and the presence of other intervening objects that can cause additional absorption.

5. How has our understanding of the Lyman alpha forest evolved over time?

Our understanding of the Lyman alpha forest has evolved significantly with advancements in technology and observations. Early studies in the 1960s and 1970s first detected the absorption lines, but it wasn't until the 1990s that the full extent and complexity of the Lyman alpha forest was revealed through observations with the Hubble Space Telescope and other ground-based telescopes.

Similar threads

  • Astronomy and Astrophysics
Replies
11
Views
3K
  • Astronomy and Astrophysics
Replies
5
Views
3K
Replies
5
Views
2K
  • Cosmology
Replies
2
Views
2K
  • Astronomy and Astrophysics
Replies
3
Views
11K
Replies
1
Views
2K
Replies
17
Views
5K
Replies
3
Views
2K
  • Astronomy and Astrophysics
Replies
25
Views
5K
Replies
13
Views
2K
Back
Top