Where can I find some easy Astro/Cosmo papers?

[dreamLord]

I'm currently a 2nd year undergrad, looking to decide which physics field to make a career out of. I'm interested in Astrophysics & Cosmology - but I don't know much about what is currently going on in these areas of science.

I thought that the best way to get some idea would be to read some papers, but the ones I've come across always make me feel extremely dumb (which I am in comparison to the authors, but still). So my questions are ; how can I attempt to read these papers? Is there any place where summaries/reviews of these papers is posted? Where can I find them?

Thanks!

 

[Stengah]

Well you need to have some background to read papers. What astrophysics classes have you taken?

If you want to start right away, I'd say start with papers in Nature. Here is a good one that was published earlier this year: http://arxiv.org/abs/1303.2723.

You might have to start by looking up some terms. For that paper, you'll need to know a bit about starburst galaxies, gravitational lensing, and redshift. That's doable for an undergrad.

I'd also recommend the textbook called Observational Cosmology by Stephen Sergeant. There is active research going on in many of the topics covered in the book, so that could be a good place to start as well before you read papers.

But probably the best way to learn about a field is to do research in it. Do you have any professors that do astrophysics or cosmology? If so, you should ask them if they have any opportunities for you.

 

[Stengah]

I should also say that at this stage, you don't need to worry about understanding every single thing in these papers. Just see if you can reconstruct the overall point, i.e. why are these results significant. Hope this helps.

 

[jtbell]

To get some idea of what's going on in those fields, you might start by following the news sections of Science and Nature regularly. Physics Today has articles which are technical but don't assume as much background in the field as regular journal articles do, so you have more of a chance of getting something out of them.

 

[Jufro]

astrobites.com

This may be in line with what you are looking for. Graduate students take publications in the general field of astronomy (everything from Kepler data to cosmology) and they try and break it down into a more understandable terms.

The actually article is also linked on occasion so that you can read the actual paper.

Hope this helps.

 

[phyzguy]

Read "The Physical Universe: An Introduction to Astronomy" by Frank Shu. After you've read and understood this book, you will be able to comprehend simple astrophysics papers, or at least get the "gist" of them.

 

[dreamLord]

Yeah, I'm trying to look for a copy of the book by Frank Shu.

Everyone else, thanks for the suggestions. The astrobites.com link seems interesting - will go through it.

Also, Stengah, even though I read up on the topics you told me to, I was unable to understand the paper. What am I doing wrong? I read the wiki pages - should I read some more?

 

[phyzguy]

Yeah, I'm trying to look for a copy of the book by Frank Shu.

Everyone else, thanks for the suggestions. The astrobites.com link seems interesting - will go through it.

Also, Stengah, even though I read up on the topics you told me to, I was unable to understand the paper. What am I doing wrong? I read the wiki pages - should I read some more?

Do you have specific questions on the paper, or are you just completely lost? If you have specific questions, go ahead and post them here and we'll try to help. If you are completely lost, you probably need to focus on learning the basics - things will make more sense as time goes on.

 

[dreamLord]

I would say I'm almost completely lost. For example, in the first paragraph of the paper itself :

A remarkable aspect of selecting sources based on their flux at millimetre wavelengths is the so-called “negative k -correction” 5 , whereby cosmological dimming is compensated by the steeply rising dust spectrum as the source redshift increases. As a result, a millimetre-selected sample should draw from the redshift distribution of dusty starburst galaxies with little bias over the entire redshift range in which they are expected to exist.

What is cosmological dimming? What is a dust spectrum? What does '..source redshift increases' mean? What does the last sentence state?

So yeah...I need to focus on learning the basics. I guess I'll start with the texts first, and move on to papers later on.

 

[Jufro]

In your OP you said that you are looking to decide what you want to do. If you want to know more about what is going on try talking to an astronomy professor.

They can condense some of the ongoing research projects. For them and in the other fields as well.

But if you have no introduction to the subject matter, then some papers will prove hard to read. This might be true for most papers you come across in any field.

Just to answer your questions (I am not 100% sure on it all so someone here may correct me):

In EM and optics we see that intensity decreases according to the inverse square law I~ 1/r². Well, for galaxies that are very far away (at high red-shift), their intensity decreases with proportion to 1/(1+z)⁴. Here, z is the red-shift of the source galaxy. This is what they call cosmological dimming. At high red-shift the effect of dimming is much quicker.

Space, as empty as it is, has a bunch of dust scattered throughout certain regions. Some places are much more dusty than others. These large dust clouds can end up with there own emission/absorption spectrum just like an atom. Not for the same reasons as an atom, but they can have their own spectrum like an atom. This is the dust spectrum. And it often makes your data harder to read sometimes.

**Here is where I would really appreciate someone jumping in and correcting me**
**Looking at a textbook I am more convinced that they are talking about looking at different galaxies (with respect to higher red-shifting) than I am in my answer below. I went back to the basic definition for red-shift in flat space time and my answer doesn't make sense.**

So, I mentioned source already, it is the object we are looking at. The object emitting the light we want to see. And we spoke about red-shift. But red-shift does not mean distance per se. Red-shifting is what happens when a wave source moves away from you (Doppler effect). It just happens to be that higher red-shifted galaxies are further away from us. So, when it says that red-shift increases it means that the source is moving away from us, I believe it means it is accelerating away because if it was moving with constant velocity the red-shift would remain constant.

The last statement, I am not too sure can you post the article you are reading, but it seems like for one reason or another, when choosing wavelengths to observe in you want to choose from the wavelengths that would be observed by the dusty galaxies. Somehow, the dust counteracts the effects of dimming. **Again, can anyone please correct me. Thanks in advance :)**