NEID Data Bitfields¶
Overview¶
Beginning in v1.2.0, the NEID DRP uses bitfields contained in header keywords DQLEVEL0, DQLEVEL1, DQLEVEL2 to compactly provide information about the data that may be useful to end users. This data is packaged as a series of nested bit-fields, as defined below, and stored in the header as an int. Each field contains up to 64 bits, although many will be unpopulated (i.e., 0).
Each byte is dedicated to a specific DRP subsystem, and the 2 least-significant-bits of each byte contain rollup assessments of the data in the following 6 bits.
The least-significant-byte contains rollup information from the other bytes. Bits 0-1 contain an overall data quality assessment, as follows: * 0: Pass * 1: Warn * 2: Fail
Bits not listed in the below tables are reserved for future use.
DQLEVEL0¶
Not currently used
DOLEVEL1¶
Byte |
Bit |
Description |
0 |
0-1 |
Overall Level 1 Assessment 0: Pass 1: Warning 2: Reject |
1 |
Manual Assessment Bits |
|
1 |
8-9 |
Summary Assessment 0: No known faults 1: Data warning 2: Data rejected |
1 |
10-15 |
Assessment Flag 0: No flags specified 1-15: Header fault description 1: Major header telemetry fault 16-32: Image fault description 32-47: Instrument/Port fault description 48-63: Other fault description 48: Telescope Summer Shutdown 49: Telescope Engineering 50: Shared Risk - General 51: Shared Risk - Commissioning 52: Shared Risk - Contreras Fire Restart 60: Wrong Star Observed |
3 |
Run Information/Manifest |
|
3 |
24-25 |
Summary Assessment 0: Sci, Cal, Eng 1: Tst |
3 |
26-27 |
Observation type (Keyword=OBSTYPE) 0: Sci 1: Cal 2: Eng 3: Tst |
5 |
Extraction |
|
5 |
40-41 |
Summary Assessment |
5 |
42 |
SNR threshold >= 80% of requested 0: Pass 1: Fail |
6 |
Wavecal |
|
6 |
48-49 |
Summary Assessment 0: wavecal == LFCpluThAr AND driftfun == dailymodel0 1: otherwise |
6 |
50 |
Wavelength calibration mode (Keyword=WAVECAL) 0: LFConly 1: LFCplusThAr |
6 |
51 |
Session Drift Correction Model (Keyword=DRIFTFUN) 0: Master 1: Constant 2: Linear 3: Simultaneous 4: DailyModel |
DQLEVEL2¶
Byte |
Bit |
Description |
2 |
Telluric model |
|
2 |
16-17 |
Summary Assessment |
2 |
18 |
|
Last Updated, 2023-08-29, DMK
