PS 4-turn Continuous Transfer Extraction Test

The PS produces the CNGS beam and extracts it at 14 GeV/c over 5-turns. Two PS batches extracted with an interval of 1.2 seconds will fill 10/11th of the SPS circumference. This beam is then accelerated up to 400 GeV/c and fast extracted from the SPS in two batches separated by 50 ms. The falling edge of the SPS extraction kicker is longer than the gap between the two batches. This causes transverse oscillations in a part of the second batch. A test to extract the PS beam over 4 turns instead of 5 turns was made successfully towards the end of the 2004 run. This mode of extraction would leave a longer gap (~3 μs instead of ~1 μs) between the two batches in the SPS and therefore the falling edge of the extraction kicker will not perturb the 2nd batch.