Overview and analysis of the 2016 Gold Run in the Booster and AGS

Simulation of 6 to 3 to 1 merge and squeeze of Au77+ bunches in AGS

“…In order to increase the intensity per Au77+ bunch at AGS extraction, a 6 to 3 to 1 merge scheme was developed and implemented by K. Zeno during the 2016 RHIC run [1]. For this scheme, 12 Booster loads, each consisting of a single bunch, are delivered to AGS per AGS magnetic cycle.…”

Comparing the effect on the AGS longitudinal emittance of gold ions from the BtA stripping foil with and without a Booster Bunch Merge

“…38 Measurements with the 12:6:2 EBIS setup indicate a factor of 1.44 in growth (initial ε = 0.51 eV-s/n) and measurements with the 8:4:2 EBIS setup indicate a factor of 1.45 in growth (initial ε=0.415 eV-s/n). 39 The ε growth in all these cases is similar even though the initial emittance varies by a factor of 7 or so. Since this growth seems largely independent of the ε at the beginning of the ramp (initial ε), the absolute amount of growth from injection energy to flattop just depends on the initial ε.…”

Beam energy scan with asymmetric collision at RHIC

“…The operation of the Booster and AGS in 2016 was reviewed in Ref. [4,5]. The beam parameters for deuteron and gold beams in Booster, AGS and RHIC were summarized in Ref.…”

“…The merging scheme for gold beam in AGS was upgraded from 8-4-2 to 12-6-2 for more intensity per bunch [4,5]. The new scheme was briefly tested in 2015.…”

“…It was found this was due to the short bunch length of the deuteron beam. The deuteron beam went through a 4-2 merge in AGS [5], therefore the longitudinal emittance is smaller than that of gold beam and the bunch is shorter. To better match the 3D sizes of the two beams in RHIC and for more deuteron intensity, the deuteron bunch was lengthened to match the gold beam.…”