MIDAS experiment „alc“ USER MANUAL SR35, 05.07.2006 Data acquisition is running on psw407 (DELL Power Edge 2600). AFS users can logon to pc5145, the local user account is l_musr_alc. Data files are stored locally on psw407 in /home/l_musr_alc/exp/alc and automatically copied to /afs/psi.
start web browser: http://psw407:8080 (PSI only!): Status page (the following screenshots are taken from pc4244…) DO NOT USE ‘Konqueror’ !!!! (only IE, Mozilla, or Firefox)
Start a run for autorun sequence: set autorun_active = 1 (if 0: only single run) there are no ‘scans’ anymore!
Stop a run Do not interfere the stopping procedure – wait until the pages refreshes and shows status ‘stopped’.
Set Magnet change Demand value read Hall probe read NMR probe - field >= 0.0 * - probe is locked * - readout unit is Tesla * - sum of returned errors (returned value < 0.0) * status unit * -1.0 BUS DRIVER I/O TIMEOUT I * -2.0 BUS DRIVER ERROR B * -4.0 not in state LOCKED !L * -8.0 state NOT LOCKED N * -16.0 state WRONG W * -32.0 state NMR signal S * -64.0 unit not Tesla !T * -128.
Set Temperature LTC21: Input: read values Output: set value LTC21_Analog_Set_Point (K)
Set Flow Demand = 3000 for T = 0 – 100 °C, set Demand = 10000 for cooling down, base temp.
History
ODB: DO NOT TOUCH! – discuss with Instrument Scientist first Start frontends from terminal by running the command alc_start_midas Shutdown all frontends: alc_mcleanup [l_musr_alc@pc4244 alc]$ alc_mcleanup Midas cleanup procedure for experiment ALC... Stopping MIDAS clients...
mozilla-bin: no process killed killing opera... opera: no process killed Cleaning up shared memory segments for user l_musr_alc ... Cleaning up semaphores for user l_musr_alc ...
Separator: vncviewer sepii:0, pw: exhalle - if only black screen appears use rdesktop sepii, user: halle, pw: exhalle under winXP: Remote Desktop Connection (All Programs – Accessories – Communications) for HV = 150 kV: SEP = 746 The beamline setting is named ALC2005_1st_period.set.
ASCII file: alc_05_NNNN.dat Data written as (run number NNNN) format: 19 header lines followed by data, lines containing 48 coloumns each !File: /home/l_musr_alc/exp/alc/alc_05_0270.dat !Run : 270 !Start/Stop time: 01:25:32 (30-04-2005) / 06:55:08 (30-04-2005) !Comment: cell 107, 15% DHTAC / 50 mole% ortho-chlorobenzoate, 35C !Field [T]: prescan = 1.5000; from = 1.5500; to = 2.3000; step = 0.0005 !Temperature (cold finger) : T1 = 346.503 K; dT1 = 0.029 K !Temperature (sample plate): T2 = 350.
Appendix: Some ODB entries Ip_min is the minimum required beam currenton Target E in mA. Measurement is paused when the current is lower. rate_min is the minimum required positron rate in the sum of the backward counters (this makes sure that the run is automatically paused when the beamblocker is closed). TestRun = ‘n’ writes datafile ‘alc_05_NNNN.dat’ TestRun= ‘y’ writes ‘test_alc_05_NNNN.
Ip_channel is the channel number (starting at 0, in the above example this is the third channel) of the proton beam current signal, 100 kHz correspond to 1 mA. preset channels is the bitmask for the scaler channels used for the preset counting register in hex form. In the above example this is the proton current (equivalent to counting for a certain number of incoming muons). 3rd channel has bitmask 0100, represented by 0x4 in hex code.
