Transient Waveform Recorder System  Data Acquisition System Documentation Summer Season (Dec 2001 ~ Feb 2002) Pole Team Wolfgang Wagner  Thomas Feser  Yuan Yan  Steve Barwick

The Transient Waveform Recorder System is designed to extend the integrated dynamic range by approximately a factor of 100, relative to the standard AMANDA DAQ. The added capability should improve the energy resolution and background rejection for high energy phenomena, including the search for EHE nu's in the downgoing direction, the search for high energy cascades, and GRBs. The goal is to assess the performance and reliability. If the results are encouraging, the plan is to extend the system to all channels. (Since the new capabilities are so advanced, maybe the new configuration with all channels connected to TWR should be changed to  "AMANDA-XE" (for eXtreme Energy), the successor of AMANDA-II ;-)

The following links show figures of  the electrical and computer connections for the Transient Waveform Recorder DAQ at the end of the Feb 2002 summer campaign. The prototype system was installed in Jan. 2002. The electrical waveforms were taken from the spare fast output of the ORM/ORB. All TWR channels are connected to fiber optic channels. The Laser Diode dAOMs are connected to an ORM with only one fast out. Therefore, to keep these channels in the muon DAQ, we inserted a linear fan out (linear to -3V, Vout/Vin ~ 0.85, AC coupled with 6us decay time).

The following documentation is available on this page:

1. TWR daq manual in postscript format and in pdf format (by Wolfgang Wagner)
2. TWR data flow at south pole (by Thomas Feser)
3. TWR - system layout as a block diagram (by Wolfgang Wagner)
4. TWR / muon - DAQ trigger connection (by Wolfgang Wagner)
5. wavemerger documentation (by Thomas Feser)
6. TWR module documentation (by Struck company)
7. GPS latch documentation (by Holger Leich)
8. MBS system introduction (by GSI)
9. our current (!) list of selected optical modules connected to TWR system an our cable map
10. A first TWR Analysis and a Method for TWR Time Calibration Talk given at Zeuthen October 2002 (by Andrea Silvestri)

1. wavemerger gzipped tar archive version 1.0
2. waveviewer gzipped tar archive in an early development state (but working)
3. wavehisto gzipped tar arvive in an even earlier development state (use with care!!!)

The VME Crate

Some general info (Jan 2002)

• Trigger Rate = 2.2 Hz at Majority Logic = 80  (we may raise this to M=100 to reduce the trigger rates)
• W. Wagner has implemented waveform suppression with individually tuned thresholds, typically between 10-15mV.
• With waveform suppression and bzipping of merged data files, we generate 800MB/day. (Gzipping would produce 1 GB/day). We therefore achieved our goal of producing less than 20% additional data. (The muon DAQ produces about 5 GB/day.)
• Wolfgang Wagner will begin to investigate "feature extraction" to further reduce file size when he returns to Wuppertal.
• Deadtimeless operation (well... really ~250us deadtime has been measured) by TWR system. However, merged files contain the same 20% deadtime that is seen in muon DAQ.
• Stability of DC offset in TWR is measured to be less than 1 channel per  2 days.
• Measured an average of 10 waveforms out of 48 TWR channels per  M=80 trigger.  (Of the 10 waveforms, about 1 is random noise) [R = (48 ch)x(10^-5s/waveform)(2x10^3Hz) ~1]

• Charge histograms for all 48 channels (gif and Root files)
• Composite Waveforms and Integrated Dynamic Range (IDR)  from N2 laser studies

• Implemented automated file merging program (wavemerger) (by T. Feser, Jan. 2002)
• Detailed charge histograms of all channels now available  using online monitor of TWR DAQ (W. Wagner, Jan 2002)
• Implemented GPS glitch suppression (W. Wagner, Jan 2002)
• Polechomper is now fetching TWR data, distributing to the wavemerger software. Merged output files are stored to tape and sent via satellite. (K. Rawlins, Jan. 2002)
• Data piped to MBS is now ~3 MB per read. This is small enough so backup RIO2 cpu should work off the shelf. (W. Wagner, Jan 2002)
• Display software, "waveviewer" superimposes TWR waveforms and LE, TE and pADC values from muon DAQ (T. Feser, Jan 2002) Explanation of graphical display: Sample waveforms.
• Automatic steering scripts for both TWR DAQ and wavemerger package are ready and implemented. (Feb 2002)
• Dynamic range calibration using in situ N2 laser on string 5 (filters nd0.0, nd0.5, nd1.0, nd2.0, nd3.0) (S. Barwick, T. Feser, 2002)
• Analysis tool for waveform adding, averaging, and charge histograms, wavehisto (Feser, Feb 2002)
•  Wavehisto includes FFT filtering to remove 5us overshoot and ringing, but inappropriate tool for pulses > 400ns FWHM(Feser, Feb2002).
•  Backup disk prepared , also notified WOs of spare GSI board (TRIVA3), spare TWR board (SIS3300), spare RIO2 cpu (in VME crate in CARA side of  MAPO), and spare system disk in MBS servercomputer
• Up to date documentation added to web site (TWR/MBS control:  W. Wagner, Feb 2002)
• WO trained to use TWR DAQ system, monitor