1 / 21

Constraining reionization using 21-cm observations in combination with CMB and Lyα forest data

Constraining reionization using 21-cm observations in combination with CMB and Lyα forest data. Jonathan R. Pritchard Abraham Loeb J. Stuart B. Wyithe. CMB optical path. Correction due to the presence of helium. Constraints from Ly α forest data. wavelength of Ly α = 121.567 nm.

yanka
Download Presentation

Constraining reionization using 21-cm observations in combination with CMB and Lyα forest data

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Constraining reionization using 21-cm observations in combinationwith CMB and Lyα forest data Jonathan R. Pritchard Abraham Loeb J. Stuart B. Wyithe

  2. CMB optical path Correction due to the presence of helium

  3. Constraints from Lyα forest data wavelength of Lyα=121.567 nm Wikipedia: In astronomical spectroscopy, the Lyman-alpha forest is the sum of absorption lines arising from the Lyman-alpha transition of the neutral hydrogen in the spectra of distant galaxies and quasars picture from http://nedwww.ipac.caltech.edu/level5/Sept01/Rauch/Rauch1.html Lyα forest

  4. Constraints from Lyα forest data average over the spectra of many quasars optical depth

  5. Observational constraints

  6. Result

  7. Constraints

  8. parameterization 1. 2. polynomial, more flexible

  9. a bimodal distribution arises because of the exclusion of models that do not ionize the Universe early enough.

  10. With increased flexibility, we still see that the IGM is largely ionized by z=8

  11. Reionization history in both parameterizations, reionization is preferred to be mostly complete by z=8 (next page)

  12. Reionization history

  13. Predicted 21cm brightness

  14. End

  15. Backup

  16. Optical depth to ionization rate Recombination coefficient average over the spectra of many quasars

  17. Ionization rate to ionizing photon production rate

  18. Evolution of the neutral fraction (volume)

  19. Analysis Bayes’theorem

More Related