Theoretical twin meteor showers

Attention is drawn to, and theoretical radiants calculated for, 27 hypothetical twin showers to Cook's (1973, in Evolutionary and Physical Properties of Meteoroids, NASA SP-319, U.S. Govt. Printing Office, Washington, D.C.) working list of meteor streams. Of these twin showers, 7 are previously known, 1 is a night-time twin to the ? Geminids, 9 are found to be contained among Sekanina's (1976, Icarus27, 265–321) radar streams, and the remaining 10 are undetected daytime showers. Minimum radii are computed for all of Cook's streams and are used to assess the possibility of detecting the twin showers.