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08/06/11: Bad fill again! The 1 st with 144 b injections (1/5). 08/06/11: Bad fill again! The 1 st with 144 b injections (2/5). 08/06/11: Bad fill again! The 1 st with 144 b injections (3/5). 18:06:44. 18:08:00. 08/06/11: Bad fill again! The 1 st with 144 b injections (4/5).
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08/06/11: Bad fill again! The 1st with 144 b injections (1/5)
08/06/11: Bad fill again! The 1st with 144 b injections (2/5)
08/06/11: Bad fill again! The 1st with 144 b injections (3/5) 18:06:44 18:08:00
08/06/11: Bad fill again! The 1st with 144 b injections (4/5) Laslett tune shift -Qs appearing! Low-intensity tune Blue= 18:07:05 Green = 18:06:53
08/06/11: Bad fill again! The 1st with 144 b injections (5/5) • => Seems really to come from mode m = - 1 => Use octupoles the next time (~ - 10 A)!
09/06/11: 1st fill with octupoles at injection and it was a good one! (1/5) Ioct finally put at 6.5 A at injection after some tests with a single bunch!
09/06/11: 1st fill with octupoles at injection and it was a good one! (2/5) 1st fill (# 1865) with Ioct = 6.5 A at injection
09/06/11: 1st fill with octupoles at injection and it was a good one! (3/5)
09/06/11: 1st fill with octupoles at injection and it was a good one! (4/5)
09/06/11: 1st fill with octupoles at injection and it was a good one! (5/5)
10/06/11: Q” meas. without and with octupoles (see LHC 08:30 meeting on 11/06/11)
24/06/11: 1236b for the 1st time in LHC and seems that transverse emittance BU was observed!!! (1/?) • Since 09/06/11, octupoles are used at injection (-6.5 A) and transverse emittance blow-up was not observed anymore • Is the BU confirmed? => Doubt in the ELogBook that the measured is good… • Did we have the Ioct at -6.5 A? => Seems yes
24/06/11: 1236b for the 1st time in LHC and seems that transverse emittance BU was observed!!! (2/?)
24/06/11: 1236b for the 1st time in LHC and seems that transverse emittance BU was observed!!! (3/?)
24/06/11: 1236b for the 1st time in LHC and seems that transverse emittance BU was observed!!! (4/?)
24/06/11: 1236b for the 1st time in LHC and seems that transverse emittance BU was observed!!! (5/?)
24/06/11: 1236b for the 1st time in LHC and seems that transverse emittance BU was observed!!! (6/?)
24/06/11: 1236b for the 1st time in LHC and seems that transverse emittance BU was observed!!! (7/?)
24/06/11: 1236b for the 1st time in LHC and seems that transverse emittance BU was observed!!! (8/?)
24/06/11: 1236b for the 1st time in LHC and seems that transverse emittance BU was observed!!! (9/?)
24/06/11: 1236b for the 1st time in LHC and seems that transverse emittance BU was observed!!! (10/?) • => According to BBQ, we don’t see huge coherent motion which was usually associated to erratic transverse emittance BU. In other words, looking only at this signal, I would not have said that strong emittance BU was observed… To be followed up.
1-batch BU seen on 06/08/11 (4/7) Why? The octupoles were ON… The intensity per bunch was just increased to ~ 1.25E11 p/b. There was some vacuum activity also… The transverse emittance BU on the 3rd batch seems to be correlated to some coherent motion in V
1-batch BU seen on 06/08/11 (6/7) The perturbed emittances are ~ constant over many hours => Can we explain this emittance BU by a factor ~2-3 in V? => Action discussed at the last Ecloud meeting