The 2D "QxQy ASCII" output files of SANS data are of the format below. Based on the instrument settings, each pixel of the 2D detector data is converted into Qx and Qy. The 2D detector is a normal XY coordinate system when viewed from the neutron source. Qx and Qy both positive is a point in the upper right quadrant and both negative is a point in the lower left quadrant. What corrections have been applied to the data depend on what (if any) reduction steps were applied before exporting the file.

In each file there is a header of information describing the sample information (gleaned from the raw data file) and information about the processing steps that were taken to generate the reduced data file. The data is in a 3-column format where the 3 columns are:

1- Qx (1/Angstrom)
2- Qy (1/Angstrom)
3- I(Qx,Qy) (1/cm)

No errors are currently carried with the data.

(only a snippet of the file is shown here)

FILE: SILIC009.SA3_SRK_S109   CREATED: 22-JAN-2008 02:39:11
LABEL: Silica 2 pct in D2O Scatt 1.3M                              
MON CNT   LAMBDA (A)  DET_OFF(cm)   DET_DIST(m)   TRANS   THICK(cm)
7.6329e+06  6       20     1.33     0.72501     0.2
BCENT(X,Y)   A1(mm)   A2(mm)   A1A2DIST(m)   DL/L   BSTOP(mm)   DET_TYP  
106.8  64.59  50    3    5.4675    0.142    50.8    ORNL  
SAM: RAW Data File: SILIC009.SA3_SRK_S109
BGD: none
EMP: none
DIV: none
MASK: none
ABS Parameters (3-6): none
Average Choices: none

*** Data written from RAW folder and may not be a fully corrected data file ***
Data columns are Qx - Qy - I(Qx,Qy)

ASCII data created Wed, May 14, 2008 1:35:44 PM

-0.3940681	-0.2451703	121
-0.3907249	-0.2451703	62
-0.387372	-0.2451703	120
-0.3840096	-0.2451703	70
-0.3806376	-0.2451703	67
-0.3772562	-0.2451703	91
-0.3738652	-0.2451703	77
-0.3704649	-0.2451703	86
-0.3670552	-0.2451703	78
-0.3636362	-0.2451703	66
-0.3602079	-0.2451703	84
-0.3567703	-0.2451703	61
-0.3533236	-0.2451703	67

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