Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Letter
  • Published:

Transition Effect in Lead of Star-Producing Radiation


IN a previous communication1, we reported our measurements on the absorption at 3,500 m. above sea-level of star-producing radiation in lead and in other materials. The data from the absorption in lead, which were the most abundant of all, pointed to the existence of a transition effect with a maximum at about 20 gm./cm.2. As this result, of particular interest in discussing the origin of the stars, was not in agreement with the results of other workers2, we carried out some new observations so as to obtain better statistical data. Though our data are not yet completely collected, we can now affirm that the transition effect in lead really exists ; and we wish to point out its particular property, namely, that it is produced almost entirely by the three-prong stars. This result is in agreement with some orientation measurements made by Amaldi and co-workers3 with fast ionization chambers.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Similar content being viewed by others


  1. Bernardini, G., Cortini, G., and Manfredini, A., Nuovo Cimento, 5, 511 (1948); Phys. Rev., 74, 845 (1948).

    Article  Google Scholar 

  2. George, E. P., and Jason, A. C., private communication.

  3. private communication.

Download references

Author information

Authors and Affiliations


Rights and permissions

Reprints and permissions

About this article

Cite this article

CORTINI, G., MANFREDINI, A. Transition Effect in Lead of Star-Producing Radiation. Nature 163, 991–992 (1949).

Download citation

  • Issue Date:

  • DOI:

This article is cited by


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing