We use different scan types (manual scan) or constant laser wavelengths to check the effects of laser cooling in the Schottky diagrams (fluorescence can not be seen in the detector), for different bunching amplitudes and frequencies:
- Scan from 1028.950 -> 1028.940, stepsize 0.001 every 10 sec
- Scan from 1028.950 -> 1028.930, stepsize 0.001 every 5 sec
- Scan from 1028.950 -> 1028.940 -> 1029.950, stepsize 0.001 every 5 sec
- Scan from 1028.950 -> 1028.940, stepsize 0.0005 "as fast as possible" 
- constant wavelengths around 1028.940
- Scan to wavelengths < 1028.940 (heating) -> Jump to 1028.945 and fast scan back to 1028.940 (-> cooling)

The cooling effects of the laser can be observed well in the Schottky spectra :)

M.Steck et al. discussed about the E-Cooler and found a possible issue. They asked for enterance to the ESR. Since nobody else was in the HKR and anyway nothing was running because of some other issues, I told, the experiment would not be disturbed and they could enter and do things. (Sth. like putting some repeller electrodes onto hand and other magical things).
It should take about 10 Minutes and might be already finished by now.

we had to open the ESR to reset a cooling device

we had to go into the ESR because the amplifiers hooked up. both amplifiers were resetted!

we also checked why we didnt see the laser at the exit window.
Laser Shutter @ the exit is closed......................... E02VVLF2t needs to be opened!

Last three pictures where taken after 
first laser ion beam overlap adjustments

It seems to be that the interactions are 
better. We also see the laser earlier and 
stronger in the schottky 

Tab "Kühler Elektronenstrahl"
An Gerät schicken

Settings für Ekühler an und aus in SC4 und 
5

~ 8 a.m.

fluorescence with detector in parking position
fixed laser wavelength
electron cooling ON, 
BUT we saw strange drifts in the Schottky spectra. It seems to be that these drifts come from the electron cooler! are the drift tubes grounded?

the drifts shift the ion beam over the transition which result in an increase of the XUV anode signal

Laser Position with scrapers verified. 
1HA: impossible to scratch laser beam, still there at -1.0 mm
2HA: +3mm --> half the laser power on detector; +4.5mm --> gone

2VO: interlock, impossible to move (beam diagnostics is informed and will check)
1VO: +0.2mm --> half laser power, +1.2: laser gone (-1.0mm: also gone)

Ion beam adapted to measured laser beam, Target bump position: -22mm (was -18mm before)
Ion beam position verified with scrapers:
1HA: -1.0mm --> still there
2HA: +4.0mm --> beam gone
Target bump angle: unchanged (+1.2 mrad)

The laser beam was adjusted in his position to overlap better with the ions.

Ion beam is destroyed at scraper position 1VO 6 mm and 2VO 4 mm; the laser beam looses half its power at 1VO 6mm and 2VO 4 mm.

EDIT: In the Schottky spectrum, we saw a stronger "cut" from the laser beam with slightly different settings in the TEM system. Later today, we could maybe finetune the ion-laser overlap while observing this "cut".

maximal transmission of PBSC (257/514 pbsc was used in combination with xlp12 detector and visual on a screen):

L/4 @ 276° & L/2 @ 348°                -->   p-polarized light


L/4 gleich auf 276° & L/2 auf ~19°     -->   s-polarized light
current position 22:15 p.m.

now we have some fun ! :D

laser reprate is seven times the revoolution frequency: 9.038283 MHz
pulse length: 735ps

H=2
H=7
H=10
H=20
H=30

We performed several scans:
Close to the bucket middle
Over the bucket
Over the bucket, jumped to the "red side" 
of the bucket and captured and cooled the 
beam again.

Laser settings:
7 times revolution frequency and 740ps 
pulses - - > 3.4 +/- 1.2 GHz

Still to do:
Switch to 240ps pulses - - > 5.8GHz 
+/-1.3 GHz

Maybe:
Switch to 117ps pulses - - > 11.0 +/- 0.8 GHz
BUT here we have less laser power (max. 50 mW right after BBO crystal, so maybe only 30 mW at the laser-ion overlap)
available. Maybe we are lucky and it is 
enough to cool also the ion beam. :) 

We saw some indications of laser cooling @ 166ps pulse length

we also see laser cooling with 285ps pulse length