• Before your beam time

    How do I submit a proposal?

    Where can I stay?

    A few options are available off-site and on-site. Check the neutron.ornl.gov users page for more information.


    How to request access to the analysis computers

    Request access by going to https://xcams.ornl.gov/

  • During your beam time

    I forgot my XCAMS password

    Simply go to How to reset password web page.


    How can I browse my data?

    Use ONCat (tutorial here).

    • view your data
    • view the metadata and get infos about such or such data set
    • find an experiment using keyword
    • More features coming soon


    How can I get help analyzing my data?

    Contact Jean Bilheux to discuss your needs.

    By going over your experiment together, Jean will show you how to run the current tools and will develop customed python notebooks if needed.


    What are those “Jupyter notebooks”?

    The Jupyter notebooks developed by Jupyter are an easy way to run python code using only a browser. By accessing our analysis computer, you won’t have anything to install. Refer to our How To page to learn how to do that.


    Where are my data and how can I access them?

    The following tutorial will show you where are your data and how you can access them. Just go to How To > Access your data.


    I get a firefox error message when trying to start the Jupyter notebooks on the analysis machine.

    After double clicking the [start jupyter] icon, I get a Firefox error message telling me that I have another Firefox window opened.

    To fix this issue, just open a terminal and type >rm -rf ~/.mozilla

    This should fix your issue and you should be able to start the Jupyter notebooks now.


    Where do I find ImageJ (FiJi) on the analysis computer?

    Just follow the following path to find and start ImageJ.

    If you need to learn how to use ImageJ, check there tutorial web site.


    What are the “metadata” and what do they mean?

    You can retrieve the metadata of your TIFF images using:

    Tag Name Description
    ImageWidth The number of columns in the image
    ImageHeight The number of rows in the image
    BitsPerSample The number of bits per component (ie. 16-bits or 32-bits for each greyscale pixel in our case)
    SampleFormat Specifies how to interpret each data sample in a pixel (1 = unsigned integer)
    SamplesPerPixel The number of components per pixel (1 in our case, which is grey scale)
    Compression 1 = None
    PhotometricInterpretation 1 = Min is black
    MakeStr The detector manufacture (eg. ‘Andor’ or ‘SBIG’)
    ModelStr The detector model number
    SoftwareStr EPICS areaDetector


    Tags 65000 to 650009 have no name and are used for timestamps and a unique ID

    Tag Name Description
    65000 EPICS timestamp. The timestamp is made when the image is read out from the camera. Format is seconds.nanoseconds since Jan 1st 00:00 1990.
    65001 Unique ID for the image. Always 1 for single image acquisition, and incrementing up for camera and CT scans. Should always match the ImageCounter value.
    65002 EPICS timestamp (seconds part only)
    65003 EPICS timestamp (nanoseconds part only)


    Scan Information

    Tag Name Description
    FileNameStr The original file name part of the constructed file name (see below)
    InstrumentStr ‘CG1D’ or ‘VENUS’
    IPTS IPTS Number
    ITEMS ITEMS Number
    SampleDescStr Sample description (user entered)
    NotesStr User notes
    DataSetStr ‘2D’ or ‘3D’
    DataAcqModeStr ‘White Beam’, ‘TOF-cold/thermal’, ‘Epithermal’ or ‘Monochromatic’
    DataTypeStr ‘OB’, ‘Raw’ or ‘DF’

    Camera/Image Information

    Tag Name Description
    ExposureTime Exposure time for the image (in seconds)
    ExposurePeriod Exposure period for the image (Exposure Time + Readout Time in seconds). Not relevant for single image exposures.
    NumImages 1= single image exposure (our normal mode of operation)
    ImageCounter Always 1 for single image acquisition, and incrementing up for camera and CT scans.
    MinX Min X pixel (0 for full frame images)
    MinY Min Y pixel (0 for full frame images)
    SizeX Size of image in X dimension (should be equal to the ImageWidth value)
    SizeY Size of image in Y dimension (should be equal to the ImageLength value)
    Temperature The setpoint temperature (in C)
    TemperatureActual The actual temperature read from the detector (in C)

    Motor Position & Scan Device

    Tag Name Description
    MotScanDeviceStr ‘Small Rot’ or ‘Large Rot’ used for this CT scan (if we are doing a camera scan or single image acquisition, this is not relevant)
    RotationActual Actual position of the rotation stage used in the CT scan (or the previous scan if we are doing a camera scan or single image acquisition)
    MotRotTable.RBV Large rotation table actual position
    MotRotTable Large rotation table setpoint
    MotSmallRotTable.RBV Small rotation table actual position
    MotSmallRotTable Small rotation table setpoint
    MotLiftTable.RBV Lift Table actual position
    MotLiftTable Lift table setpoint
    MotShortAxis.RBV Short axis actual position


    TIFF file header example

    TIFF Directory at offset 0x800008 (8388616)
      Image Width: 2048 Image Length: 2048
      Bits/Sample: 16
      Sample Format: unsigned integer
      Compression Scheme: None
      Photometric Interpretation: min-is-black
      Samples/Pixel: 1
      Rows/Strip: 2048
      Planar Configuration: single image plane
      Make: Unknown
      Model: Unknown
      Software: EPICS areaDetector
      Tag 65000: 837380408.136687
      Tag 65001: 1
      Tag 65002: 837380408
      Tag 65003: 148080423
      Tag 65010: FileNameStr:TiffHeaderTests
      Tag 65011: InstrumentStr:CG1D
      Tag 65012: IPTS:17255
      Tag 65013: ITEMS:-1
      Tag 65014: SampleDescStr:polarization test
      Tag 65015: NotesStr:polarization test
      Tag 65016: DataSetStr:2D
      Tag 65017: DataAcqModeStr:White Beam
      Tag 65018: DataTypeStr:Raw
      Tag 65019: ModelStr:DW936_BV
      Tag 65020: ManufacturerStr:Andor
      Tag 65021: ExposureTime:1.000000
      Tag 65022: ExposurePeriod:5.451660
      Tag 65023: NumExposures:1
      Tag 65024: NumImages:1
      Tag 65025: ImageCounter:1
      Tag 65026: MinX:0
      Tag 65027: MinY:0
      Tag 65028: SizeX:2048
      Tag 65029: SizeY:2048
      Tag 65030: Temperature:-60.000000
      Tag 65031: TemperatureActual:-57.830002
      Tag 65032: MotScanDeviceStr:Small Rot
      Tag 65033: RotationActual:183.000132
      Tag 65034: MotLiftTable.RBV:247.500452
      Tag 65035: MotLiftTable:247.500452
      Tag 65036: MotShortAxis.RBV:76.000000
      Tag 65037: MotShortAxis:76.000000
      Tag 65038: MotLongAxis.RBV:193.016000
      Tag 65039: MotLongAxis:193.016000
      Tag 65040: MotRotTable.RBV:182.996500
      Tag 65041: MotRotTable:183.000000
      Tag 65042: MotSmallRotTable.RBV:183.000132
      Tag 65043: MotSmallRotTable:183.000000
      Tag 65044: MotDetTable.RBV:200.000000
      Tag 65045: MotDetTable:200.000000
      Tag 65046: MotCameraVert.RBV:-51.699796
      Tag 65047: MotCameraVert:-51.699796
      Tag 65048: MotHoriTrans.RBV:28.000000
      Tag 65049: MotHoriTrans:28.000000
      Tag 65050: MotVertTrans.RBV:60.000000
      Tag 65051: MotVertTrans:60.000000
      Tag 65052: MotDiffuser.RBV:86.300000
      Tag 65053: MotDiffuser:86.300000
      Tag 65054: MotAperture.RBV:138.700000
      Tag 65055: MotAperture:138.700000
      Tag 65056: MotSlitVB.RBV:39.969938
      Tag 65057: MotSlitVB:39.969938
      Tag 65058: MotSlitVT.RBV:39.860484
      Tag 65059: MotSlitVT:39.860484
      Tag 65060: MotSlitHR.RBV:40.000000
      Tag 65061: MotSlitHR:40.000000
      Tag 65062: MotSlitHL.RBV:39.977781
      Tag 65063: MotSlitHL:39.977781
      Tag 65064: AndorCCDCooler:1
      Tag 65065: AndorCCDTempStatusStr:Not stabilized at set point
      Tag 65066: AndorCCDPreAmpGain:0
      Tag 65067: AndorCCDADCSpeed:2

  • After your beam time


Laboratories utilities

Analysis/Visualization tools