1 / 15

Does the fine structure constant vary?: A detailed investigation into systematic errors

This detailed study explores systematic errors affecting the fine structure constant using multiple methods and expert analyses. Led by Chris Churchill and featuring contributions from renowned physicists, the investigation covers atmospheric dispersion effects, isotopic ratio evolution, and various calibration errors. Key methodologies include line removal techniques and thorough consistency checks. The findings indicate that known systematic errors cannot solely account for observed results, prompting future measurements and checks with advanced instruments. This research is crucial for understanding fundamental physical constants.

amethyst-randall
Télécharger la présentation

Does the fine structure constant vary?: A detailed investigation into systematic errors

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. Does the fine structure constant vary?:A detailed investigation into systematic errors With: Chris Churchill (PSU) Victor Flambaum (UNSW) Jason Prochaska (UCSC) Wallace Sargent (Caltech) Rob Simcoe (Caltech) John Webb (UNSW) Arthur Wolfe (UCSD)

  2. Outline:Systematic errors for the MM method • Detailed analyses: • Atmospheric dispersion effects • Isotopic ratio evolution • Consistency checks • Line removal • Other tests for simple, unknown systematics

  3. Candidate systematic errors: • Wavelength calibration errors – JOHN’S TALK • Instrumental profile variations • Laboratory wavelength errors (wz=w0+qx) • Line blending • Temperature changes during observations • Heliocentric velocity variation • Atmospheric dispersion effects • Isotopic ratio evolution • Differential isotopic saturation • Hyperfine structure effects See Murphy et al., 2001, MNRAS, 327, 1223 for details •  •  •  •  •  •  • ? • ? •  • 

  4. Atmospheric dispersion effects:

  5. Atmospheric dispersion results: Pre-rotator Post-rotator Rotator

  6. Isotopic ratio evolution:

  7. Isotopic ratio evolution:

  8. Isotopic ratio evolution results: Isotope

  9. Line removal checks:

  10. Removing MgII2796: Post-removal Pre-removal Line Removal

  11. Removing MgII2796: Post-removal Pre-removal Line Removal

  12. Number of systems where transition(s) can be removed Pre-removal Post-removal Transition(s) removed

  13. Other line-removal tests: Low-z (0.5 – 1.8) High-z (1.8 – 3.5) ZnII FeII SiIV FeII Positive MgI, MgII Mediocre Anchor Mediocre Negative CrII

  14. Correcting for both systematics: Rotator + Isotope

  15. Conclusions: • Main systematics: • Atmospheric dispersion • Isotopic ratio evolution • Known systematic errors cannot explain results • Nor can simple, unknown systematics Future: • Iodine cell measurements planned for Keck • Independent optical check required: VLT & Subaru • Sleep loss?

More Related