Self-consistent analysis of OH-Zeeman observations: Too much noise about noise

Telemachos Ch Mouschovias, Konstantinos Tassis


We have recently re-analysed in a self-consistent way OH-Zeeman observations in four molecular-cloud envelopes and we have shown that, contrary to claims by Crutcher et al., there is no evidence that the mass-to-flux ratio decreases from the envelopes to the cores of these clouds. The key difference between our data analysis and the earlier one by Crutcher et al. is the relaxation of the overly restrictive assumption made by Crutcher et al, that the magnetic field strength is independent of position in each of the four envelopes. In a more recent paper, Crutcher et al. (1) claim that our analysis is not self-consistent, in that it misses a cosine factor, and (2) present new arguments to support their contention that the magnetic field strength is indeed independent of position in each of the four envelopes. We show that the claim of the missing cosine factor is false; that the new arguments contain even more serious problems than the Crutcher et al. original data analysis; and we present new observational evidence, independent of the OH-Zeeman data, that suggests significant variations in the magnetic field strength in the four cloud envelopes.

Original languageEnglish (US)
Pages (from-to)801-807
Number of pages7
JournalMonthly Notices of the Royal Astronomical Society
Issue number2
StatePublished - Dec 1 2010



  • Diffusion
  • ISM: clouds
  • ISM: magnetic fields
  • MHD
  • Stars: formation
  • Turbulence

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

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