Neutral Particle Detector (NPD) Information

Last Updated: April 18, 2006 by Sandee Jeffers

NPD

Document References:

ASPERA-3 Proposal, Part I: Scientific and Technical Plan, ~865 kb, 50 pages
NPD IDFS Design Document, ~684 kb, 270 pages

General Information:

Number of Detectors: 2 - NPD1 and NPD2
Charged Particle Removal Grid Voltage: 0, 8 kV
Grid Removal Operational Modes: 3 (on, off, switched)
Number of Start MCPs: 2
Number of Stop MCPs: 3
Number of Directions: 3
Number of Mass Steps: 16
Number of Energy Steps: 16
Raw Bit Rate: 64 kbps

There are 10 Virtual Instruments for the Neutral Particle Detector:

10 Science Data - 5 each for NPD1 and NPD2
- NPD1:
  1. NPD1 Raw Science data mode of 4 sensors: 2 16-bit streams contain the TOF, Direction, Coincidence, and Stop PH values (NPD1RAW, for NPD1 RAW data mode)
  2. NPD1 TOF Science mode of 3 directions (sensors), 16 PHD bins and 16 TOF bins: 16 bits per sample; 32 samples per sec. (NPD1TOF, for NPD1 TOF mode)
  3. NPD1 Science Bin Matrix mode data of 3 directions in 1 x 16 matrix: 16 bits per sample; 32 samples per sec. (based on 31.25 msec instrument cycle time); 1 x 16 refers to mass (hydrogen/oxygen combined) x 16 TOF bins (NPD1BM1, for NPD1 Bin Matrix 1 x 16 matrix mode science data)
  4. NPD1 Science Bin Matrix mode data of 3 directions in 2 x 16 matrix: 16 bits per sample; 32 samples per sec. (based on 31.25 msec instrument cycle time); 2 x 16 refers to mass (hydrogen/oxygen separated) x 16 TOF bins (NPD1BM2, for NPD1 Bin Matrix 2 x 16 matrix mode science data)
  5. NPD1 Science Bin Matrix mode data of 3 directions in 16 x 16 matrix: 16 bits per sample; 32 samples per sec. (based on 31.25 msec instrument cycle time); 16 x 16 refers to 16 PHD bins x 16 TOF bins (NPD1BM16, for NPD1 Bin Matrix 16 x 16 matrix mode science data)
  NPD2:
  1. NPD2 Raw Science data mode of 4 sensors: 2 16-bit streams contain the TOF, Direction, Coincidence, and Stop PH values (NPD2RAW, for NPD2 RAW data mode)
  2. NPD2 TOF Science mode of 3 directions (sensors), 16 PHD bins and 16 TOF bins: 16 bits per sample; 32 samples per sec. (NPD2TOF, for NPD2 TOF mode)
  3. NPD2 Science Bin Matrix mode data of 3 directions in 1 x 16 matrix: 16 bits per sample; 32 samples per sec. (based on 31.25 msec instrument cycle time); 1 x 16 refers to mass (hydrogen/oxygen combined) x 16 TOF bins (NPD2BM1, for NPD2 Bin Matrix 1 x 16 matrix mode science data)
  4. NPD2 Science Bin Matrix mode data of 3 directions in 2 x 16 matrix: 16 bits per sample; 32 samples per sec. (based on 31.25 msec instrument cycle time); 2 x 16 refers to 2 masses (hydrogen/oxygen separated) x 16 TOF bins (NPD2BM2, for NPD2 Bin Matrix 2 x 16 matrix mode science data)
  5. NPD2 Science Bin Matrix mode data of 3 directions in 16 x 16 matrix: 16 bits per sample; 32 samples per sec. (based on 31.25 msec instrument cycle time); 16 x 16 refers to 16 PHD bins x 16 TOF bins (NPD2BM16, for NPD2 Bin Matrix 16 x 16 matrix mode science data)
3 Engineering Data (Health & Safety, Monitors, Voltages)
1. 18 8-bit Engineering Monitor and Reference values: 2 detectors with 9 monitor/reference values (bias, deflection, start bias, stop bias monitors and references, plus temperature monitor) each (2 x 9 = 18); 8 bits per sample (NPDENG8, for NPD ENGineering 8-bit data)
2. 13 NPD Status indicators: 11 1-bit values indicating on/off or disabled/enabled states, 2 4-bit values indicating the 2 detector modes (NPDENGS, for NPD ENGineering Status indicators)
3. 20 16-bit NPD data register values: 16 16-bit registers, 4 8-bit registers (NPDENG16, for NPD ENGineering 16-bit registers)