ISSN:0031-9228    

DOI:10.1063/1.3022869

出版商:AIP    

年代:1971

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.3022835

出版商:AIP    

年代:1971

数据来源: AIP

摘要:

The mysterious long‐lived K meson has produced another surprise. An experiment to look forKL0→&mgr;+&mgr;−has failed to find any such decays and has established an upper limit to the branching ratio (for two‐muon decay compared to all decays) of1.82×10−9,with a 90&percent; confidence level. Straightforward theoretical estimates had predicted a branching ratio of about10−8,but in any case a fairly plausible lower bound of6×10−9,more than three times larger than the experimental upper limit. The experiment was done at the Berkeley Bevatron by Alan Clark, Tom Elioff, Clive Field, Henry Frisch, Rolland Johnson, Leroy Kerth and William Wenzel, all of Lawrence Radiation Laboratory, Berkeley (Phys. Rev. Lett., 28 June).

ISSN:0031-9228    

DOI:10.1063/1.3022837

出版商:AIP    

年代:1971

数据来源: AIP

摘要:

If you bombardFe56withO16ions, you can observeC12ions being emitted, which means that an alpha particle (really two protons and two neutrons whose relative motions are probably correlated as they are in an alpha particle) has been incorporated in the residual nucleus—in this caseNi60.The spectrum shows certain selected states and not others. That is, at certain specific energies the alpha particles find an easy way to get in—the system appears to resonate. Such experiments with alpha‐particle transfer reactions are exciting great interest among nuclear physicists.

ISSN:0031-9228    

DOI:10.1063/1.3022838

出版商:AIP    

年代:1971

数据来源: AIP

摘要:

Interest ran high at the special session on theA2meson, held at the Washington APS meeting. Many of those who crowded into the room hoped that a new experiment designed to duplicate the original CERN experiment would at last settle the question of whether or not theA2is split, that is, does it exist as two identical particles differing only in mass by 3&percent;?

ISSN:0031-9228    

DOI:10.1063/1.3022839

出版商:AIP    

年代:1971

数据来源: AIP

摘要:

By “ultrafast” we mean those light pulses that last from about10−13seconds to a few tens of picoseconds. The anticipation of using them to study ultrafast processes in physics and chemistry has stimulated efforts to produce these pulses, and the results have been good; in 1962 the shortest pulse available was10−8sec, but by 1968,10−13‐sec pulses had been produced at powers up to10−12watts. Progress has been due largely to the perfection of “mode‐locking” methods, through which we arrange the phase relations between the axial modes of the laser. Here we shall discuss the ways ultrafast pulses are produced and measured. Then we can consider their usefulness in, for example, studying stimulated scattering, measuring excited‐state lifetimes and creating high‐temperature plasmas.

ISSN:0031-9228    

DOI:10.1063/1.3022840

出版商:AIP    

年代:1971

数据来源: AIP

摘要:

Nearly all scholarly journals use referees to screen submitted manuscripts. Physical scientists recognize the significance of the referee system: Some defend the system, and others attack it. But refereeing itself has not been systematically assessed. By studying the archives ofThe Physical Reviewfor the years 1948 to 1956 (before the separate publication ofPhysical Review Letters) we have been able to come to a few conclusions about the workings of the referee system. Although some of the results were expected, others are surprising. Younger physicists, for example, are more likely to have their papers accepted than are older physicists, and the physics “establishment” does not appear to have any bias toward publishing the papers of its own members. The referee system here apparently does what it is supposed to do: Sift out the good papers from the bad.

ISSN:0031-9228    

DOI:10.1063/1.4725749

出版商:AIP    

年代:1971

数据来源: AIP

摘要:

One of the great puzzles of elementary‐particle physics is how to understand the relationships between the muon and the electron. The set of properties that the muon and electron possess in common are collectively described by the phrase “muon–electron universality.” This set is large and comprises most of the properties of the muon and electron; see Table 1, page 44.

ISSN:0031-9228    

DOI:10.1063/1.3022841

出版商:AIP    

年代:1971

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.3022842

出版商:AIP    

年代:1971

数据来源: AIP

ISSN:0031-9228    

DOI:10.1063/1.3022843

出版商:AIP    

年代:1971

数据来源: AIP