Relative RF phase measurement for HOM resonace study, 15-Apr-2001 ----------------------------------------------------------------- On 16 Apr 2001 a multibunch HOM heating test of the Belle IR was performed. Bunch patterns 10100 and 10000 (simple 5 bucket spacing), known to cause much larger IR heating than normal were checked out. 10:20-12:01 LER only, 10100 pattern, 1843 bunches filled * current gradually raised, temp. vs. current dependence measured 12:11-12:45 LER only, 10000 pattern * current gradually raised, temp. vs. current dependence measured 12:58-13:43 HER only, 10000 pattern * same behaviour as LER only 14:05-14:26 HER and LER, 10000 pattern, both beams 100mA * test to see if relative RF phase between LER and HER beams affect temperature increase - confirmed that it does 15:09-17:30 HER and LER, 10000 pattern, both beams 200mA * measurement of the temperature dependence on the relative RF phase of the 2 beams Temperature and RF phase data was logged (see 2 mails below for details) and temp. and RF data were merged into one file. For each set value of RF phase the temperature in last 2 minutes of operation at that phase was averaged for each sensor. In this way temperatures stabilized sufficiently. Relevant data is summarized in table below: time tmp(49) tmp(50) tmp(51) tmp(52) RF phase sqrt(noent) ----------------------------------------------------------------------------- 15.0000 14.2295 13.9972 12.9209 10.6244 -43.0000 7.74597 15.2506 13.9698 13.7347 12.6534 10.3627 -40.0000 7.74597 15.3339 13.7872 13.4846 12.4013 10.1652 -37.0000 7.74597 15.4172 13.6299 13.3770 12.2783 10.0141 -34.0000 7.74597 15.5006 13.5953 13.3210 12.2004 9.9512 -31.0000 7.74597 15.5839 13.6157 13.3611 12.2261 9.9756 -28.0000 7.74597 15.7172 13.7391 13.4656 12.3635 10.1386 -25.0000 7.74597 15.7839 13.9457 13.7369 12.6070 10.3191 -22.0000 7.74597 15.8672 14.2437 14.0133 12.9224 10.6505 -19.0000 7.74597 15.9339 14.5226 14.2999 13.2456 10.9277 -16.0000 7.74597 16.0172 14.5550 14.2962 13.2347 10.9630 -13.0000 7.74597 16.1006 14.2983 14.0724 12.9842 10.6817 -10.00000 7.74597 16.2006 13.9995 13.7455 12.6519 10.3991 -7.00000 7.74597 16.2839 13.7720 13.5276 12.4148 10.1485 -4.00000 7.74597 16.3839 13.6172 13.3588 12.2872 10.0129 -1.00000 7.74597 16.4506 13.6348 13.3251 12.2317 9.9743 2.00000 7.74597 16.5172 13.6887 13.4082 12.2993 10.0586 5.00000 7.74597 16.6006 13.8224 13.5916 12.4597 10.2172 8.00000 7.74597 16.8506 14.0416 13.7965 12.6800 10.4349 11.0000 7.74597 16.9839 14.3981 14.1875 13.1000 10.7971 14.0000 7.74597 17.0506 14.5876 14.3517 13.3025 11.0278 17.0000 7.74597 17.1172 14.3571 14.1032 13.0482 10.7682 20.0000 7.74597 17.2172 14.0246 13.7922 12.6891 10.3925 23.0000 7.74597 17.3672 13.6733 13.4333 12.3450 10.0500 26.0000 7.74597 Temperature vs. RF phase dependence was plotted (see eps plots) and different fits were performed: 1: T(RF) = p1 + p2 cos(2 pi/p3 (RF-p4) ) 2: T(RF) = p1 + p2(cos(2 pi/p3 (RF-p4) ) + p5)**2 data function period (deg) All data 2 31.85 (see eps plot) Last 2 min 2 31.75 Last 2 min 1 31.62 The fit is better with function 2, but not supported by simple physics where the resonator is periodically excited to a damped oscillation. * Beam current correction not done (needs well-motivated function) * Thermal expansion is not taken care of (10% effect). Including it in the fit gives unreasonably large thermal expansion. *************************************************** From toru.tsuboyama@kek.jp Tue Apr 17 08:49:04 2001 *************************************************** Database file which was recorded every two seconds is bwgx:/bdaqsvd/d0/usr/svddaq/svd05/report/april15.hbook The above data is averaged over every 20 sample (for about 30 seconds) and saved to the following ntuple file. bwgx:/bdaqsvd/d0/usr/svddaq/svd05/report/april15s.hbook According to http://belle.kek.jp/~svd/monitor/hbook_def_14.html, the data is aligned as follows. beam(1) LER current beam(2) HER current temp(25) IP chamber center 1 temp(26) IP chamber center 2 temp(49) BP-F-0 temp(50) BP-F-90 temp(51) BP-F-180 temp(52) BP-F-270 temp(53) BP-B-0 temp(54) BP-B-90 temp(55) BP-B-180 temp(56) BP-B-270 *********************************************** From junji.haba@kek.jp Tue Apr 17 08:49:29 2001 *********************************************** The ntuple file corresponding to the beam study conducted on 15 Apr. (IP chamber HOM study) is placed in /g1data/haba/monitor/hbk/daily/apr01/apr15.hbk New variables "rfphase7" and "rfphase8" are added to see the relative RF phase of LER. (both should be same in a nomal operation.)