IMPROVED EMITTANCE AND BRIGHTNESS FOR THE MAX IV 3 GeV STORAGE RING

At MAX IV Laboratory, the Swedish Synchrotron Radia-
tion (SR) facility, the largest of two rings operates at 3 GeV
with a bare lattice emittance of 330 pmrad . Upgrade plans
are under consideration aiming at a gradual reduction of the
emittance, in three stages: a short-term with an emittance
reduction of 20% to 40%, a mid-term with an emittance
reduction of more than 50% and a long-term with an emit-
tance in the range of the diffraction limit for hard X-rays
( 10 keV). In this paper we focus on the short-term case, re-
suming previous work on a proposed lattice that can reach
270 pmrad emittance, with only minor modifications to the
gradients of the magnets of the present ring, i.e. without any
hardware changes and all within the present power supply
limits. Linear lattice characterisation and calculations of key
performance parameters, such as dynamic aperture and mo-
mentum aperture with errors, are described and compared to
the present operating lattice. Experimental tests of injection
into this lattice are also shown.