We shielded the PMTs, i.e., the N2 tube, which improved the Cu PMT background rate.

Without beam and ESR lights off:

PMT Mitte: 4 Hz
PMT Nord: 1 Hz
PMT Cu: 240 Hz

And now also in English :) 

The ion beam is back in the ESR! 
Apparently, there was a slit moved in. (Maybe even 2)

This could have been GEEXDR11S and/or the GEEXDR1AS 

We now have the following parameters: 

SIS injection energy = 537.5 MeV/u  (we did not change this) 
Chopper window 70 us (we did not change this) 

We now have about 1.2e9 ions per injection in the ESR

The additional signals from PMTs and XUV detector needed for spectroscopic analysis in the second DAQ are patched to AP Messhütte (MH) via the red patch panel at the inside of the target region. The patch channels F1 to F8 (also labeled A to H in red on white) are used and extended by a cable bundle to reach below the mirror chamber. Inside the MH the signals arrive at the red patch panel and are forwarded to the blue patch panel close to the laser DAQ using channels 1 to 8 (also labeled A to H).
 
The entire connection for these 8 channels from the mirror chamber to the blue panel has been tested with a pulser signal of ~115mV amplitude. After transfer the amplitude has decreased to ~40mV, see also attached fotos.

The signal transport time from the mirror chamber to the blue panel is ~407 ns. This was measured by patching a logic puls from ESR to MH and back to ESR, as show in the delay_ESR... foto attached.  

we had no injections in the ESR again 

it turned out that the injection kicker of the ESR has a problem 

since the WM readout still does not work reliably, I started a python script at atppc023 that saves timestamp and wavemeter frequency. in folder wavemeter at the desktop. 

it is about 1 MB / h

Rename the old file and restart when you change the wavelength range.

Some further information regarding the 
xuv-detector and its components.

The Xuv-detector cabel channels seem to be 
wrongly labeled in the Messhütte (see 
picture) and are propably also wrongly 
connected. Need to be relabeled and reconnected either in the 
messhütte or in the laserlab. I will look for the best 
solution tomorrow morning. 

I co controlled all detector signals and 
adjusted the threshold to be just above 
the noise. I will double check this when 
the detector can be moved in and we have a 
beam. 

Count rates were measured for the XUV-
detector for a full circle:
Cathode: -5V, shields: 0V, main coil 8A, 
sec coil 2A, 
No beam - pos 0mm: ~10 Hz
Hot beam - pos 0mm: ~5 kHZ
Cool beam - pos 147mm: ~200Hz

When the XUV-detector has to shut down unexpectedly, it can happen that the Mesytek power supply crashes and can't be 
communicated with. If this happens the Mesytec PS needs to be restarted from hand inside of the ESR. This can be done by 
restarting the crate located at the bottom of the XUV-detector. 

This crash happened during the night shift today and the Mesytec should be restarted today as soon as possible. For 
example when the laser stabilization gets fixed.

In normal operation this should never happen if no mistakes are made. 

Check regularly if the connection to the XUV and Cu detectors are still active and the detectors move in (after injection) and out (after killing the ion beam). 

Therefore, 2 programs should run on the computer where you can also see the running Schottky.

One of the programs is for the XUV and one is for the Cu mirror.
There the Automisation button should be activated!!!

ID 30 contains the manual how to run / start and operate both detectors.

Problem solved. Ignore this entry








If the wavemeter reading is not shown correctly in Go4 - Step2 - Labview:

Close Labview, close WM software (all windows)

Start WM software, start Labview, restart MBS

We changed the fiber to the wavemeter. The third fiber worked best and we could operate the WM at low exposure times, i.e., below the laser repetition rate. We used the neutral density filter to adapt the laser power that only one laser pulse is measured by the WM each time (Exposure time =34ms)

This way, there are no frequency jumps. The jitter is slighly different at each wavelength which was ~5GHz peak to peak.


We optimized the fiber coupler and slightly optimized the jitter to <4GHz.