1. Technical news:

· The engineers investigated the reasons for unexpected shut down of ISOLDE targets, which happened several times in the last weeks. In some cases this is related to false alarms triggering the safety interlocks, which are designed to cut the power to the targets if there is an indication of a problem. The water flow to one of the targets was found to be close to the lower limit for safe operation, therefore the flow was increased. On some occasions sparking of the high voltage causes a false reading of a particular vacuum gauge. A second gauge in the same section was introduced as a backup and now the interlock is linked to the “and” of the two readouts, rather than looking at just one. Hopefully, the above changes will already improve the reliability of ISOLDE operations.

· The RF amplifier of ISCOOL had to be replaced last week. The designer and producer of this device is one of the ISOLDE engineers. He will be back on Monday to look into the problem. In the mean time the possibility for replacing the prototypes with a commercial device is being investigated.

· Many of us remember the random communication problems occurring with the ISOLDE controls. In such cases reboot of the dedicated server was the only solution. However, it was discovered this week that a spare PLC used for REX had an electronic address assigned identical to another existing device. The communication problems should disappear after the fix.

· The calibration of GPS does not work properly. The beam position changes when changing from one mass region to another. The problem is related to the controller box which uses as a reference the readout from the Hall probe. The specialists are looking for a solution.

· There is a new utility introduced in the ISOLDE controls (trial mode). It is a program that reads the proton cycle and records the sequence in the electronic logbook. This is useful for some experiments, in particular in cases where the lifetime is comparable with the period of the proton pulses.

· It is strongly recommended that outside working hours there is always an experienced user on shift who is familiar with the basic ISOLDE controls relevant to his experiment. Several hours of beam time have recently been lost due to lack of basic knowledge by shift members. Beginner users should take the separator course!

· Answering a question to the coordinator concerning the maximum beam energy available at ISOLDE: The last indications are that 50keV are currently possible at both separators. However, the conditions change from one target to another.

(comment from the author of these minutes: less than 10 years ago 60keV was the beam energy available nearly all the time. Now this energy seems to be a rare privilege.)

2. News from experiments:

· The CRIS experiment established a reasonable transmission to the last section of this newly installed apparatus.

· The beams of ^201,203,205Au were successfully produced at ISOLDE and studied by the IS447 experiment. It was discovered that gold is not released when running the target conservatively. The target was kept for this run at about 2100 °C.

(comment from the author of these minutes: such temperatures, which correspond to about 800A target current, were not unusual in the past).

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