New galactic population class | Nature

ABSTRACT GALACTIC γ rays have been shown to come from regions where H2 is dense, and where also ‘population I’ objects are predominantly found. The existence of such regions can be

interpreted using the density-wave model of spiral galaxies, and leads us to propose here a change in the Baade classification scheme: ‘population I’ now to include all the objects

associated with the H2 clouds, and a new class, ‘population 0’, to refer to the regions, relatively richer in atomic hydrogen, which lie further from the galactic centre. Access through your

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(1974). Article  ADS  CAS  Google Scholar  Download references AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Theoretical Studies Group, NASA Goddard Space Flight Center, Greenbelt,

Maryland, 20771 F. W. STECKER Authors * F. W. STECKER View author publications You can also search for this author inPubMed Google Scholar RIGHTS AND PERMISSIONS Reprints and permissions

ABOUT THIS ARTICLE CITE THIS ARTICLE STECKER, F. New galactic population class. _Nature_ 260, 412–414 (1976). https://doi.org/10.1038/260412a0 Download citation * Received: 17 November 1975

* Accepted: 11 February 1976 * Issue Date: 01 April 1976 * DOI: https://doi.org/10.1038/260412a0 SHARE THIS ARTICLE Anyone you share the following link with will be able to read this

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