PDS_VERSION_ID = PDS3 RECORD_TYPE = FIXED_LENGTH RECORD_BYTES = 760 FILE_RECORDS = 1376 ^ARRAY = "MOD3FIT3.DAT" DATA_SET_ID = "VEGA1-C-PUMA-2-RDR-HALLEY-V1.0" TARGET_NAME = HALLEY START_TIME = "UNK" DESCRIPTION = "The data for this set were originally received as 4,027 separate FITS files, one for each spectrum. These files have been reformatted and combined into four tables, one for each of the PUMA instrument operating modes. Within each table, the spectra are in order of original FITS file number. This order is assumed to be chronological. This file contains spectra taken in mode 3, max/time mode. In this mode the amplitude and t**2 (time of flight) generator are sampled at each maximum in the spectrum. Samples are also taken every 8.6 microseconds if no other sampling occurred. Samples triggered by maxima are flagged." OBJECT = ARRAY NAME = RECORD_ARRAY AXES = 1 AXIS_ITEMS = 1376 INTERCHANGE_FORMAT = BINARY OBJECT = COLLECTION NAME = VEGA1_PUMA_RECORD_3 BYTES = 760 START_BYTE = 1 DESCRIPTION = "Each record in the dataset consists of 43 bytes of observational parameters followed by up to 239 samples. Each sample consists of three bytes: the time-of-flight value, the amplitude value, and a triggering flag." OBJECT = ELEMENT NAME = SEQUENCE DATA_TYPE = MSB_UNSIGNED_INTEGER BYTES = 4 START_BYTE = 1 DESCRIPTION= "Sequence number of the spectrum. This number is not necessarily unique, and cycles more than once through the range of unsigned two-byte integers." END_OBJECT OBJECT = ELEMENT NAME = EVENT DATA_TYPE = MSB_UNSIGNED_INTEGER BYTES = 4 START_BYTE = 5 DESCRIPTION= "Event number of the spectrum. This number is not necessarily unique, and cycles more than once through the range of unsigned, two-byte integers." END_OBJECT OBJECT = ELEMENT NAME = TIME DATA_TYPE = MSB_UNSIGNED_INTEGER BYTES = 4 START_BYTE = 9 DESCRIPTION= "Time of the spectrum on the BLISI clock, in seconds. Spectra in each mode table are arranged chronologically, which happens to coincide with the order of the original individual FITS file numbers." END_OBJECT OBJECT = ELEMENT NAME = DISTANCE DATA_TYPE = MSB_UNSIGNED_INTEGER BYTES = 4 START_BYTE = 13 DESCRIPTION= "Distance to the nucleus, in kilometers" END_OBJECT OBJECT = ELEMENT NAME = LENGTH DATA_TYPE = MSB_INTEGER BYTES = 2 START_BYTE = 17 DESCRIPTION= "Length, in bytes, of the SPECTRUM array. In mode 3 this is 3x the number of amplitude samples taken (i.e., sample = LENGTH / 3)." END_OBJECT OBJECT = ELEMENT NAME = VOLTAGE DATA_TYPE = MSB_INTEGER BYTES = 2 START_BYTE = 19 DESCRIPTION= "Multiplier voltage, which controls sensitivity and dynamic range of the mass spectrum." END_OBJECT OBJECT = ELEMENT NAME = IR DATA_TYPE = MSB_UNSIGNED_INTEGER BYTES = 1 START_BYTE = 21 DESCRIPTION= "Impact rate - the number of events occurring per second." END_OBJECT OBJECT = ELEMENT NAME = IRL DATA_TYPE = MSB_UNSIGNED_INTEGER BYTES = 1 START_BYTE = 22 DESCRIPTION= "Impact rate for events which exceed the x100 discriminator voltage (large events)." END_OBJECT OBJECT = ELEMENT NAME = IR4 DATA_TYPE = MSB_UNSIGNED_INTEGER BYTES = 1 START_BYTE = 23 DESCRIPTION= "Number of events per second which also show a spectrum corresponding to class 4-7 events." END_OBJECT OBJECT = ARRAY NAME = COUNTER_CLASS AXES = 1 AXIS_ITEMS = 5 START_BYTE = 24 DESCRIPTION= "This counter array holds running totals for events with coincidences and spectra. In order, these counters sum: 1 No coincident events 2 Dual-coincidence events 3 Triple-coincidence events 4 Events with a spectrum 5 Events with class >=5 " OBJECT = ELEMENT NAME = COUNTER_CLASS_ELEMENT DATA_TYPE = MSB_UNSIGNED_INTEGER BYTES = 1 END_OBJECT = ELEMENT END_OBJECT OBJECT = ARRAY NAME = SENSITIVITY AXES = 1 AXIS_ITEMS = 5 START_BYTE = 29 DESCRIPTION= "Sensitivity values for each part of the instrument: 1 Target 4 Catcher grid 2 Accelerator grid 5 Monitor 3 Photomultiplier A value of 1 indicates high sensitivity; 0 low sensitivity." OBJECT = ELEMENT NAME = SENSITIVITY_ELEMENT DATA_TYPE = MSB_UNSIGNED_INTEGER BYTES = 1 END_OBJECT = ELEMENT END_OBJECT OBJECT = ELEMENT NAME = MODE DATA_TYPE = MSB_INTEGER BYTES = 1 START_BYTE = 34 DESCRIPTION= "The spectrum mode. In this file MODE is always 3." END_OBJECT OBJECT = ELEMENT NAME = CLASS DATA_TYPE = MSB_INTEGER BYTES = 1 START_BYTE = 35 DESCRIPTION= "Class of this event. Following are the event classes: 0 Already transferred to telemetry 1 One front-end signal only 2 One coincidence between two front-end channels (target, accelerator grid and photomultiplier) but no spectrum 3 All front-end coincidences, but no spectrum 4 Minimum of 52/46/10 entries on the spectrum for modes 1/2/3, respectively 5 Between 54/48/12 and 228/148/140 entries in the spectrum, and 26/21/6 entries in the mass window (6-58u) 6 Class 5 events which also have a minimum of 2 entries of at least 1/5 full scale between mass 5 and 8 7 Class 5 events with a minimum of 34/27/12 entries in the mass window, but not more than 93/49/46 8 Statistical sample 9 Test pulses from the test-pulse sequence 10 Spectra of the multiplier stimulus, the emitter " END_OBJECT OBJECT = ARRAY NAME = AMPLITUDE AXES = 1 AXIS_ITEMS = 5 START_BYTE = 36 DESCRIPTION= "Amplitude on each detector: 1 Target 4 Catcher grid 2 Accelerator grid 5 Monitor 3 Photomultiplier " OBJECT = ELEMENT NAME = AMPLITUDE_ELEMENT DATA_TYPE = MSB_UNSIGNED_INTEGER BYTES = 1 END_OBJECT = ELEMENT END_OBJECT OBJECT = ARRAY NAME = NOISE AXES = 1 AXIS_ITEMS = 3 START_BYTE = 41 DESCRIPTION= "Noise on the front-end channels: 1 Target 2 Accelerator grid 3 Photomultiplier " OBJECT = ELEMENT NAME = NOISE_ELEMENT DATA_TYPE = MSB_UNSIGNED_INTEGER BYTES = 1 END_OBJECT = ELEMENT END_OBJECT /* The spectrum array */ OBJECT = ARRAY NAME = SPECTRUM AXES = 1 AXIS_ITEMS = 717 START_BYTE = 44 DESCRIPTION= "Each spectrum point consists of three bytes: a time, an amplitude and a triggering flag." OBJECT = COLLECTION NAME = SPECTRUM_POINT BYTES = 3 OBJECT = ELEMENT NAME = TIME_OF_FLIGHT DATA_TYPE = MSB_UNSIGNED_INTEGER BYTES = 1 START_BYTE = 1 DESCRIPTION= "The value of the t^2 generator. The TIME_OF_FLIGHT may have values from 0-255. Duplicate values of TIME_OF_FLIGHT may occur when a time-triggered sample is immediately followed by an amplitude-triggered sample. Also, the value 255 may repeat several times at the end of a spectrum." END_OBJECT OBJECT = ELEMENT NAME = AMPLITUDE DATA_TYPE = MSB_INTEGER BYTES = 1 START_BYTE = 2 DESCRIPTION= "The amplitude value. This is a positive integer in the range 0-127." END_OBJECT OBJECT = ELEMENT NAME = TRIGGER_FLAG DATA_TYPE = MSB_INTEGER BYTES = 1 START_BYTE = 3 DESCRIPTION= "This byte contains a value of 1 if the preceding AMPLITUDE sample was triggered by the amplitude. In mode 2 samples are also taken every 8.6 micro- seconds if no amplitude triggered a sample within that time. For these time-triggered samples the TRIGGER_FLAG contains 0." END_OBJECT END_OBJECT = COLLECTION /* SPECTRUM_POINT */ END_OBJECT = ARRAY /* SPECTRUM */ END_OBJECT = COLLECTION /* VEGA1_PUMA_RECORD_2 */ END_OBJECT = ARRAY /* RECORD_ARRAY */ END