Low-energy positrons of high intensity at the new positron beam facility NEPOMUC

In summer 2004 the NEutron-induced POsitron source MUniCh—NEPOMUC—of the new Munich research reactor FRM-II was set into operation at the nominal reactor power of 20 MW. With this novel facility one of the worlds most intense low-energy positron beam is now available. Intensity and positron beam profile measurements were performed at 1 and 30 eV, respectively. Within the first reactor cycle a yield of up to 10 8 moderated positrons per second was achieved. In the present arrangement of NEPOMUCʹs instrumentation the monoenergetic positron beam is magnetically guided to a coincident Doppler broadening (CDB) facility and to a positron-induced Auger electron spectroscopy (PAES) analysis chamber.