Minutes of nanoBPM meeting on 7 October, 2004

"alignment of the KEK system", H. Yamaoka

(transparencies, 1 page, pdf, 374KB )

Precise alignment has been done with the SMART laser tracker system by M. Takano. Instead of him, Yamaoka reported the final results. Origin of coordinate is a point of 630 (700) mm from the upstream (downstream) on the beam line. the longitudinal position of the whole system was shifted by 3mm to the upstream, i.e. &Delta z=-3mm everywhere in the system. The center of three sensor cavities were calculated to be aligned at (x,y)=(0.051,-0.18), (0.045,-0.07) and (0.04,0.05) along the beam direction (z). Therefore, these alignment errors can be tolerable.

The special metal studs will arrive on 8 October (tomorrow). So, they will be used for fixing the SUS plate on the granite table, where the reference postions will be monitored by the SMART.

"Status of KEK nano-BPM", Y. Inoue

The resonant frequencies of the reference cavities were adjusted by squeezing cavities. The results are listed in a following table, where unit is GHz;

nano-BPMsensor cavityref. cavity:before:after
no.16.55156.54056.5515
no.26.55046.53346.5504
no.36.55106.54056.5510
As clearly seen in the table, the frequencies were able to be adjusted within 100KHz. Since "after" measurements were done immediately after the adjustment, third measurement must be interested to see the stability.

"Status of the system", Y.Honda

As final components in the mover system, metal studs will arrive for fixing the cavities on the V-block in next week. Also the electronics for 2nd and 3rd cavities are waited for the arrival.

The cables and a rack have been installed. The electrical connections were checked including the power lines. LAN cables are also available. However,a hub-station is failed to operate properly now, which is repaired soon.

First in the beam test, data will be read-out independently of the ATF control system by using our PCs. So, the data shall be synchronized with the ATF pulse by a scalar in similar way as the SLAC/LLNL system.

The schedule was reminded as follows;

The next meeting will be held in 14 October, 2004, at 1:30pm-, 3-gokan 325.