IMP-8 Pc_Pha File Format



IMP-8 Pc_Pha file begin with an ASCII header that describes each of the
data fields (columns) in the file. The actual data follows the header
and is in binary format as specified on the first line of the header.
The columns are grouped into records called verses in order to group
data of a similar kind i.e. data from a given particle telescope.
The group of verses that make up an event or time period is called a
chapter.

More detail information , see document Low-Energy Cosmic-Ray Group
PC Data Base  written by Don V. Reames.



The following indicated the format descriptor for the data field. Descriptor Description ---------- ----------- T2 Begin and end time L Long integer (32 bits) R2 Ratio of float count and live time (2*32 bits) I Single integer (16 bits) B bit field (16 bit) - used for tag bits
Header record's format Names Format Description ------ ------- ------------- qline1 A80 data type and creation Date qline2 A80 satellite name and file title qsemi A4 semicolumn qline4 A80 starting time of first chapter in file qline5 A80 stopping time of last chapter in file qline6 A45 average interval qsemi A4 semicolumn qline8 A8 qline9 A28 qsemi A4 semicolumn qpha1 A20 verse type (I8VLETSUM1) q1l A40 byte count qrate1 A45 DI.Dii.S1D.-F q1di A40 DI channel q1dii A40 DII channel q1e A40 E channel q1t A40 tags qpha2 A20 verse type (I8VLETSUM2) q1l A40 byte count qrate1 A45 DI.Dii.S1D.-F q1di A40 DI channel q1dii A40 DII channel q1e A40 E channel q1t A40 tags Data record's format Names Format Description ------ ------- ------------- HVR0 I2 time verse type number=0 IBEG I4 chapter starting time IEND I4 chapter stopping time HVR1 I2 event verse type number=1 NCTP1 I4 number bytes in rest of verse IRTCT1 I4 rate count IRTLT1 I4 rate live time HPHA1 I2 PHA 1 HPHA2 I2 PHA 2 HPHA3 I2 PHA 3 HTAG I2 tag bit field repeat from HPHA1 to HTAG through NCTP1 HVR2 I2 event verse type number=2 NCTP0 I4 number bytes in rest of verse IRTCT0 I4 rate count IRTLT0 I4 rate live time HPHA1 I2 PHA 1 HPHA2 I2 PHA 2 HPHA3 I2 PHA 3 HTAG I2 tag bit field repeat from HPHA1 to HTAG through NCTP0

Sample header records

BINARY CREATED 2001 11 20 13:33:44 ; DATA TYPE & CREATION DATE IMP-8 DATA FILE ; SAT. NAME(S) & FILE TITLE ; 2001/07/24 00:00:00 ; STARTING TIME OF FIRST CHAPTER IN FILE 2001/10/26 00:00:00 ; STOPPING TIME OF LAST CHAPTER IN FILE 30 MIN ; AVERAGE INTERVAL ; #0 RATE T2 TIME ; #1 PHA I8VLETSUM1 L 0 200000 BYTE COUNT R2 1 1.0E5 DI.DII.S1D.-F I 0 4096 188. DI I 0 4096 188. DII I 0 4096 188. E B 0 FFFF TAGS #2 PHA I8VLETSUM2 L 0 200000 BYTE COUNT R2 1 1.0E5 DI.DII.S2D.-F I 0 4096 188. DI I 0 4096 188. DII I 0 4096 188. E B 0 FFFF TAGS ; END