4. New Measurements of the Cosmological Distance Ladder
- Title: The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: baryon acoustic oscillations in the Data Release 9 spectroscopic galaxy sample
- Authors: L. Anderson, E. Aubourg, S. Bailey, et al.
- First Author’s Institution: Department of Astronomy, University of Washington
Why it is important: If you want to know what is making our universe accelerate, you need excellent measurements of how it is accelerating. Specifically, you want to know the total amount the universe has expanded during the time photons traveled from distant sources (redshift) as a function of the current distances to these sources, and this requires either a standard candle or a standard ruler.
Next: (#3) We are Small, but We are Many! Kepler Measures an Increasing Frequency of Small Planets
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Hi Betsy:
Just a note– it looks like the arXiv link that you have on the first page of this article does not link to the title you provide.
The link looks like it goes here:
http://arxiv.org/abs/1106.0499
“How supernova feedback turns dark matter cusps into cores”
instead of here:
http://arxiv.org/abs/1107.1261
“Keck Spectroscopy of Faint 3<z<8 Lyman Break Galaxies:- Evidence for a Declining Fraction of Emission Line Sources In the Redshift Range 6<z<8"
Thanks,
Dave
Ah, actually the links are just switched–
Thanks,
Dave
Thanks Dave! The links are now fixed.
Fascinating articles! But counting citations seriously distorts what astronomy is about. Because most young astronomers today work in observational cosmology, 10/12 papers are on that topic, the most glamorous frontier. But 10/12 of the most significant new papers of 2012 (selected some other way) paint a certainly much broader canvas, and reflect the amazing scope of astronomical research!
Only the search for new planets (another glamour topic) and new calculations of the evolution of rotating stars in the HR diagram (a classic issue in stellar astronomy) penetrated the top twelve. So much more was missing!
Nonetheless, an interesting citation poll.
Hi, I think the mass-to-light ratio of a low-mass star is higher than that of a high-mass star. In addition, the Salpeter IMF has more low-mass stars than the Kroupa and Chabrier IMFs.
I think that the article in astrobites has more detail introduction:
http://astrobites.com/2012/02/16/the-imf-is-not-universal/
Yes, I had the mass-to-light ratio section entirely backward; this is now corrected (and consistent with the linked astrobite). Thank you!!