I started the upstream XGMs in XTD2, XTD1, and XTD10.

Status of machine SASE tuning (just before switching off for monday maintenance):

Gun Modulator Problems

Gun Trip at 11:23 and since then the Modulator trips after each restart.
Accelerator Shift Crews and On Call personnel working on fixing the issue.

Update for elog 99:

Now Gotthard timing is changed to new setting for 0.5 MHz.

attached screenshot with gothard timing setting

Machine changed from 0.5 MHz to 1.1MHz new screenshot attached2

After SASE1 HIREX GOTTHARD reconfiguration, we now get a single pulse per frame. This was verified by comparing data from HIREX recorded with 564 kHz and 1.13 MHz X-ray repetition rates. Both intensity and number of peaks is comparable for the two repetition rates.

Reply to elog103:

Spoke with Machine RC Thomas Wamsat and SQS.

Machine RC has some ideas to try. SQS have agreed that they can give 30 min for the machine to optimize the intensity.

SA1 has no impact while the machine trying to improve the power for SA3.

Update at 21.17hr

Machine RC has optimized for higher pulse intensity for SQS from 900uJ to 1600uJ. But still, the problem reported in elog103 exists, However, SQS can work now and overnight.

Thanks to Thomas Wamsat for his effort to support.

Machine RC Raimond informed PRC that there is an issue with the A4 module that needs to fix to have a continuous operation. To fix this they need 20 min.

Agreed with all instruments (SPB, SQS, and HED) that at 13:30hr machine will take over the beam for 20 min.

Update: 13:55hr

Machine finished fixing the issue for the A4 module and beam handover to all beamlines.

The machine tuning over the night had not yet accomplished fully satisfactory beam conditions mainly at the high photon energies for SA1 and SA2,
therefore tuning continued during WED morning.
Beam was handed over to SCS (SASE3) at 9h with about 2.4mJ at 2.5 keV.
Beam was handed over to FXE (SASE1) at 13h with about 530uJ at 19.5 keV.
Tuning for MID (SASE2) at 23 keV is agreed to continue until 14h, currently at a level of 120 uJ. 

- SA2 photon beamline

Today morning found the CRL1: 5 and 6 arm and Pop-in 45-I are still IN. I have retracted them.

SA2 photon beamline

- SRA position were 7 mm x 7 mm, MID reported they see the hallow of beam shadow at MID Popin

- I have closed the SRA to 3.5 mm x 3.5 mm

The Cryo team solved the problems, beam is back.
Downtime from 17h59 until 21h03.

Beam is back at around 11:30 pm

We lost 1 hr 30 min of beam time.(it was promised to get back at around 10:00 am)

If we want to change the pulse number then we need to call BKR.

Photon Activities by XPD colleagues in SA3 are concluded on Sunday 23.07 at 17:00. The photon commissioning activities are concluded for this week.

The PRC agrees with RCs to handle beam back to BKR for further tuning activities while touching common nobs.

After the 12 hour cryo failure last night, it was decided to exchange a faulty window with some reduced transmission at the injector laser today (see email by Andreas to xo-info yesterday). 

This was sucessful and the injector tunnel was closed today 16:40 and restart of the gun is ongoing. Tomorrow ramp up and SASE tuning.

The hope is that the large jitter and the poor SASE performance of last week can be now improved.  Beam delivery to instrument is expected on Thursday. 

As discussed, there will be a beam interuption form 14:45 until probably 15:45 related to jitter studies at A1 that the BKR would like to try out. 

Harald

Good news: The 'jitter'-tests was sucessful and BKR could identify the jitter source related to a wrong software setting around the AH1 module of injector.

This was now fixed and the jitter has disappeared  . It is likely that the tuning was compromised by this setting from the beginning of this run (July11).

On Monday morning, a fresh tuning round will be started with hopefully improved SASE performance. Until then photon delivery with what we have.  

Photon beam delivery status:

- Machine informed that beam will be handover to instruments SA1 (SPB/SFX) and SA3 (SXP) at 18.30hr

- Machine needs more time for SA2 and the next update will be at 20hr.

This message has been communicated to instruments.

- Machine updates;

Saturday 1:30 hr Cold compressor failed. The initial estimation of downtime was 20 hr, later in today morning crew gave a new estimation of time of 30 hr. So the machine will be switched on and beam delivery to instruments will be tomorrow morning. Today at 3 pm, I will get more information and a clear picture of the best estimation time for beam delivery.

Naresh

Dear All,

Two important machine updates.

1) Still, the forecasted time for the start-up of the machine will be tomorrow morning.

2) After discussion with machine RC, it is confirmed that beam delivery is extended by 24 hr, so the beam is available till 7 am Tuesday morning for instruments.

Just want to point out, that this is a very exceptional case that it is extended by 24 hours as there will be a blue week(in wk 35).

The below programs have been canceled keeping in view of the user program and beam delivery is important for instruments. Sorry for this.

153339 - Euler MDL calibration for SASE2 mirrors M1, M2, M3: Antje 

158376 - Beamtime for Safety tests (HED Preabsorber): Eric

156699 - SASE3_XTD10 Virtual Spectrometer: Joakim

157789 - Chirp-dispersion short pulses study (further decoupling from SASE1): Svitozar

Stay tuned to the public display tomorrow morning for the machine's status.

thanks

Naresh

PRC wk 34

Info from MRC (Lars)

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The cryo crew reports that the cold compressor that failed is, alas!,
the new one with the magnetic bearing. They have to wait for a colleague
who is not on call to help them with the problem. We expect an update on
their further plans around noon and our status panels have been updated
to reflect that.

Cheers,
Lars

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