Scanning probe detector channel descriptions

Back to Scanning Probe Diffraction Quick Reference

Some common definitions of 26ID scan detector channels

Detector Channel number	EPICS Process variable	Description
D01	26idsclr1:scaler1.S1	I0 - Integrated Ion chamber current after NES slits (change current amplification via yellow SR570 tab on main beamline screen)
D02	26idcXMAP:mca5.R1	Bi - Fluorescence channel from outboard detector, summed ROI#1 - find and modify with MCA software from User Tools tab on main beamline screen
D03	26idcXMAP:mca5.R2	Ti - Fluorescence channel from outboard detector, summed ROI#2 - find and modify with MCA software from User Tools tab on main beamline screen
D04	26idcXMAP:mca5.R5	Fe - Fluorescence channel from outboard detector, summed ROI#5 - find and modify with MCA software from User Tools tab on main beamline screen
D05	26id:ccd.R01.Average	Integrated Intensity/Num Pixels for CCD ROI#1 - ROI#1 defines the total active chip area to be saved, so this is the total CCD intensity per pixel
D06	26id:ccd.R02.Average	Integrated Intensity/Num Pixels for CCD ROI#2 - usually tightly defined around the outgoing beam - Contrast here is related to diffracting volume
D07	26id:ccd.R02.XCentroid	X center of mass of intensity in CCD ROI#2 - This is related to lattice strain and rotation in the diffraction plane, scales away from center of ROI2 with signal/dark current
D08	26id:ccd.R02.YCentroid	Y center of mass of intensity in CCD ROI#2 - This is related to lattice rotation out of the diffraction plane, scales away from center of ROI2 with signal/dark current
D09	26idcDET:userCalc3.VAL	R02.Average - R03.Average, Background subtracted average intensity - ROI#3 typically set around an unused area, this is useful for viewing scans in progress with low contrast
D10	26idcDET:userCalc6.VAL	CCD Image number - If you are using the CCD DO NOT MODIFY THIS CHANNEL - Necessary for Matlab analysis routines
D11	26idctsrc:DMM1:Ch1_raw.VAL	Channel 1 - C Hutch digital multimeter - FOMX temperature
D12	26idctsrc:DMM1:Ch2_raw.VAL	Channel 2 - C Hutch digital multimeter - FOMY temperature
D13	26idctsrc:DMM1:Ch3_raw.VAL	Channel 3 - C Hutch digital multimeter - FOMZ temperature
D14	26idctsrc:DMM1:Ch4_raw.VAL	Channel 4 - C Hutch digital multimeter - SAMX temperature
D15	26idctsrc:DMM1:Ch5_raw.VAL	Channel 5 - C Hutch digital multimeter - SAMY temperature
D16	26idctsrc:DMM1:Ch6_raw.VAL	Channel 6 - C Hutch digital multimeter - SAMZ temperature
D17	26idctsrc:DMM1:Ch7_raw.VAL	Channel 7 - C Hutch digital multimeter - SAM Theta temperature
D18	26idpvc:userStringCalc3.VAL	Time of day - Units are fractional hours (ie 22.5 = 10:30pm) - use min and max of a linear scan to accurately estimate 2D scanning times, discontinuity in this channel indicates a hung scan
D19	-	-
D20	-	-
D21	B26ID-CG-DCM-01:PFEED	Feed pressure of LN2 cryocooler internal circuit - spikes at refill, adjust fill cycle levels and remove ice from vent line to minimize this
D22	B26ID-CG-DCM-01:MNLEV	Cryocooler main vessel LN2 level - level of external unpressurized LN2 bath, this activates the fill cycle, dewar currently is kept between 80-60% full
D23	26id:BLEPS:MIRROR TEMP 01:RBV	First mirror temperature - RTD readout - useful to monitor equilibration after a beam dump
D24	26id:BLEPS:MIRROR TEMP 02:RBV	Second mirror temperature
D25	26id:BLEPS:XTAL_TEMP_01:RBV	DCM first crystal temperature - typically -234 deg F
D26	26id:BLEPS:XTAL_TEMP_02:RBV	DCM second crystal temperature - typically -171 deg F
D27	26idctsrc:bpmds:current:total	Alternate I0 - integrated intensity on all four quadrant diodes at the front of C Hutch - mono beam intensity measurement that does not depend on NES slit settings or exposure times
D28	26idctsrc:bpmds:pos:x	Approximate X (horizontal) position of mono beam in microns at the front of C hutch - related to mirror piezo and DCM chi2 stability
D29	26idctsrc:bpmds:pos:y	Approximate Y (vertical) position of mono beam in microns measured at the front of C hutch - primarily related to DCM theta2 stability
D30	S:SRcurrentAI	Alternate I0 - APS storage ring current value, useful for normalizing long scan data when the ring is not in top-up mode - unexpected changes of this value indicate orbit/steering loss or beam dump
D31	B26ID-CG-DCM-01:PFEED	Feed pressure of LN2 cryocooler internal circuit - spikes at refill, adjust fill cycle levels and remove ice from vent line to minimize this
D32	B26ID-CG-DCM-01:MNLEV	Cryocooler main vessel LN2 level - level of external unpressurized LN2 bath, this activates the fill cycle, dewar currently is kept between 80-60% full
D33	26id:BLEPS:MIRROR TEMP 01:RBV	First mirror temperature - RTD readout - useful to monitor equilibration after a beam dump
D34	26id:BLEPS:MIRROR TEMP 02:RBV	Second mirror temperature
D35	26id:BLEPS:XTAL_TEMP_01:RBV	DCM first crystal temperature - typically -234 deg F
D36	26id:BLEPS:XTAL_TEMP_02:RBV	DCM second crystal temperature - typically -171 deg F
D37	26idctsrc:bpmds:current:total	Alternate I0 - integrated intensity on all four quadrant diodes at the front of C Hutch - mono beam intensity measurement does not depend on NES slit settings or exposure times
D38	26idctsrc:bpmds:pos:x	Approximate X (horizontal) position of mono beam in microns at the front of C hutch - related to mirror piezo and DCM chi2 stability
D39	26idctsrc:bpmds:pos:y	Approximate Y (vertical) position of mono beam in microns measured at the front of C hutch - primarily related to DCM theta2 stability
D40	S:SRcurrentAI	Alternate I0 - APS storage ring current value, useful for normalizing long scan data when the ring is not in top-up mode - unexpected changes of this value indicate orbit/steering loss or beam dump