Timeline for How did UV from the earliest stars 'alter the state of the 21 cm line' such that it shows up in CMB today?
Current License: CC BY-SA 3.0
7 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Mar 27, 2019 at 8:58 | vote | accept | uhoh | ||
| Apr 4, 2018 at 9:06 | answer | added | pela | timeline score: 5 | |
| Apr 3, 2018 at 22:01 | answer | added | Giuseppe Rossi | timeline score: 7 | |
| Mar 14, 2018 at 1:50 | history | tweeted | twitter.com/StackAstronomy/status/973738140723744768 | ||
| Mar 1, 2018 at 15:36 | comment | added | uhoh | @CarlWitthoft I'm guessing it has something to do with the 21 cm line being associated with the electron in the n=1 level. If excited by UV, the hyperfine splitting is going to be very different and there won't be a transition at 21 cm anymore. But how that affects the blackbody spectrum is complicated. | |
| Mar 1, 2018 at 15:12 | comment | added | Carl Witthoft | Sounds like multi-photon absorption, where the second absorption can only take place when the electron is in a short-lived excited state. Is that what you're thinking of? | |
| Mar 1, 2018 at 12:41 | history | asked | uhoh | CC BY-SA 3.0 |