IGOR Pro Developers Working Group

From canSAS
Revision as of 20:51, 23 December 2007 by Ilavsky (talk | contribs) (→‎News/Status)

Mailing List Archive

Members

  • Jan Ilavsky (APS)
  • Andrew Jackson (NIST)
  • Steve Kline (NIST)
  • Ken Littrell (ORNL)
  • Andy Nelson (ANSTO) (chair)

News/Status

USAXS (= "Indra2") data naming structure APS USAXS instrument can operate with either slit smeared and 2-D collimated geometry. Practically for all samples with meaningful thickness the intensity data are absolutely calibrated ([1/cm]). Errors for intensity are always estimated. Q units are 1/A. The Q resolution (width of bin in Q) is same for all points - 1e^-4 [1/a] and therefore is not reported. Q-bin smearing is practically not necessary. Significant fraction of samples exhibit multiple scattering effects for which we attempt to make correction for absolute intensity calibration. Most of data processing parameters are stored in keyword list in the wave note.

List of wave names and description: SMR_Int, SMR_Error, SMR_Qvec slit smeared Intensity, Error, and Q. Slit length is in the wave note M_SMR_Int, M_SMR_Error, M_SMR_Qvec slit smeared data, absolute intensity corrected for multiple scattering effects DSM_Int, DSM_Error, DSM_Qvec de-smeared (using Lake method) or 2-D collimated data M_DSM_Int, M_DSM_Error, M_DSM_Qvec de-smeared or 2-D collimated data, absolute intensity corrected for multiple scattering effects

Nika data naming structure Nika is universal package for reduction of 2D data into 1D "lineouts" for Igor Pro. It is used mostly for X-ray SAXS and WAXS instruments (synchrotron & desktop). It can output data either as function of Q, angle, or d-spacing. It can generate either maximum number of Q points (one Q per pixel on detector) or re bin the points to smaller number, or re bin the points to semi-logarithmic distribution in Q. It provides width of bin in Q as additional wave with each data for tools which enable accounting for Q-bin smearing. To identify the sector parameters (or circular average), "_ending" is attached to the end of output wave names: "_C" circular average "_Angle_HalfWidth" sector average around direction of Angle with sector +/- HalfWidth example: "_10_5" average around 10 degrees direction with sector 10 degrees (+/- 5 degrees) wide. Or to use another description - sector between lines in 5 degrees and 15 degrees azimuth on the detector.

List of data types "QRS" namings structure: q_sampleName_ending Q with units in [1/A] r_sampleName_ending Intensity with units 1/cm (if data are calibrated) s_sampleName_ending Error for intensity (statistical error from averaged pixels) w_sampleName_ending Q bin width optionally instead of Q one can use: t_sampleName_ending Two theta value in degrees d_samplename_ending d-spacing value in A