On the apparent narrowing of radio recombination lines at high principal quantum numbers
| aut.researcher | Gullaer, Sergei | |
| dc.contributor.author | Alexander, J | |
| dc.contributor.author | and Gulyaev, S | |
| dc.date.accessioned | 2011-12-16T03:14:26Z | |
| dc.date.available | 2011-12-16T03:14:26Z | |
| dc.date.copyright | 2011 | |
| dc.date.issued | 2011 | |
| dc.description.abstract | We critically analyze the Bell et al. findings on "anomalous" widths of high-order Hydrogen radio recombination lines in the Orion Nebula at 6 GHz. We review their method of modified frequency switching and show that the way this method is used for large \Delta n is not optimal and can lead to misinterpretation of measured spectral line parameters. Using a model of the Orion Nebula, conventional broadening theory and Monte Carlo simulation, we determine a transition-zone n = 224...241 (\Delta n = 11...14), where measurement errors grow quickly with n and become comparable with the measurement values themselves. When system noise and spectrum channelization are accounted for, our simulation predicts "processed" line narrowing in the transition-zone similar to that reported by Bell et al. We find good agreement between our simulation results and their findings, both in line temperatures and widths. We conclude, therefore, that Bell et al.'s findings do not indicate a need to revise Stark broadening theory. | |
| dc.identifier.citation | The Astrophysical Journal, 745:194 (6pp), 2012 February 1 | |
| dc.identifier.doi | 10.1088/0004-637X/743/1/1 | |
| dc.identifier.uri | https://hdl.handle.net/10292/3136 | |
| dc.publisher | IOPScience | |
| dc.relation.uri | http://dx.doi.org/10.1088/0004-637X/745/2/194 | |
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| dc.rights.accessrights | OpenAccess | |
| dc.subject | Astrometry | |
| dc.subject | Kuiper belt | |
| dc.subject | General | |
| dc.subject | Planets and satellites | |
| dc.subject | Dynamical evolution and stability | |
| dc.subject | Formation | |
| dc.title | On the apparent narrowing of radio recombination lines at high principal quantum numbers | |
| dc.type | Journal Article | |
| pubs.organisational-data | /AUT | |
| pubs.organisational-data | /AUT/Design & Creative Technologies | |
| pubs.organisational-data | /AUT/Design & Creative Technologies/School of Computing & Mathematical Science | |
| pubs.organisational-data | /AUT/PBRF Researchers | |
| pubs.organisational-data | /AUT/PBRF Researchers/Design & Creative Technologies PBRF Researchers | |
| pubs.organisational-data | /AUT/PBRF Researchers/Design & Creative Technologies PBRF Researchers/DCT C & M Mathematical Science |