NICERMASTR - NICER Master Catalog
NICER's X-ray Timing Instrument (XTI) consists of an aligned collection of 56 X-ray "concentrator" optics (XRC) and silicon drift detector (SDD) pairs working in the energy range of 0.2-12 keV. Each XRC collects X-rays over a large geometric area from a roughly 30 arcmin2 region of the sky and focuses them onto a small SDD. The SDD detects individual photons, recording both energies (with a 3% energy resolution at 6 keV) and high precision times (with 100 nanoseconds RMS relative to Universal Time).
During one day of operation, NICER monitors several sources. For each observed source the data are divided into intervals of one day and labeled with a sequence number. This database table contains one record for each sequence number and includes parameters related to the observation.
The Neutron star Interior Composition ExploreR (NICER): Design and Development: Gendreau, K.C., Arzoumanian, Z. et al. 2016, Proc. SPIE 9905, Space Telescopes and Instrumentation 2016: Ultraviolet to Gamma Ray, 99051H (22 July 2016)
This is the designation of the pointed target.
Right Ascension of the pointing position. Note that the pointing position can be different from the target position.
Declination of the pointing position. Note that the pointing position can be different from the target position.
Galactic Longitude of the pointing position. Note that the pointing position can be different from the target position. This parameter has been added by the HEASARC and is calculated from the J2000 pointing position.
Galactic Latitude of the pointing position. Note that the pointing position can be different from the target position. This parameter has been added by the HEASARC and is calculated from the J2000 pointing position.
The start time of the observation.
The time corresponding to the end of the observation.
The unique number to identify an observation/sequence. This is a 10-digit number.
The original target identifier is a number assigned by the NICER planning system to each target. It is not unique. Different observations of the same target may have associated different target identifier numbers.
The unique target identifier is a number assigned after the NICER data processing. This number is unique and all observations of a specific target always have associated the same target identifier number. If the unique value has not yet been assigned, the value is set to -1.
Right Ascension of the target position. This is the position of the target used by the NICER planning system.
Declination of the target position. This is the position of the target used by the NICER planning system.
The effective total observation exposure, in seconds, after data cleaning.
The time awarded for this target, in seconds. The value of zero is assigned to all observations that are not part of the Guest Observer program.
The unfiltered exposure (in seconds) for the MPU0 (Measurement Power Unit).
The unfiltered exposure (in seconds) for the MPU1 (Measurement Power Unit).
The unfiltered exposure (in seconds) for the MPU2 (Measurement Power Unit).
The unfiltered exposure (in seconds) for the MPU3 (Measurement Power Unit).
The unfiltered exposure (in seconds) for the MPU4 (Measurement Power Unit).
The unfiltered exposure (in seconds) for the MPU5 (Measurement Power Unit).
The unfiltered exposure (in seconds) for the MPU6 (Measurement Power Unit).
The number of Focal Plain Modules (FPM) after the data screening.
This records the status of the processing of the data from the observation. The strings are VALIDATED, PROCESSED, or NOTPROCESSED. If the string is VALIDATED implies that the data are located in the archive. If the string is PROCESSED implies that the data have been processed but not validated yet. If the string is NOTPROCESSED implies that the data have not been processed.
This parameter records the date when the data were last processed.
This is the date when the data became public.
This records the version of the processing script used in the pipeline to generate the data products for the observation.
This records the number of times a data set has been processed.
This records the version of the NICER CALDB version. This is encoded as genYYYYMMDD_xtiYYYYMMDD, such that YYYYMMDD represents the date of the index file.
This records the version of the HEAsoft and NICER software used in the processing pipeline to generate the data products of the observation.
This number uniquely identifies the proposal that originated the observation.
This parameter contains a short description of the aim of the observation.
The subject category is a string that identifies the type of object observed by NICER and associated to this sequence number. These strings have the following meanings:
BURST : Observations of X-ray burst sources CAL : Calibration observations DIR : Director's discretionary time ENG : Engineering data (generally non-science) LCM : Observations of pulsar lightcurves (useful for modeling) MAGNETAR : Observations of magnetars OSWG : Observatory Science Working Group observations SEARCH : X-ray pulse search targets TIMING : Pulsar observations having to do with calibration of absolute timing
Each subject category is assigned a numerical code, and this field contains that numerical value for the specified subject category.
The last name of the proposal's Principal Investigator.
The first name of the proposal's Principal Investigator.
The cycle number of the proposal. The value of 0 is used for the check-out phase, corresponding to the first observing month.
The type of observation. Possible values and their respective meanings: NOR for a normal observation, CAL for a calibration observation with the detector in nominal configuration, CALOFFNOM for a calibration observation with the detector not in the nominal configuration, and DDT for discretionary director time. The CALOFFNOM observations have the first four digits of the obsid set to A014 where A is the cycle number (e.g. 1, 2, 3..). These observations can not be analyzed with the standard methods. The values NOR-TOO, CAL-TOO, and DDT-TOO are assigned if the observation is also a target of opportunity.
The title of the proposal that originated the observation.
This flag parameter is a numeric value that indicates whether or not the observation has been coordinated with other observatories.
If the observation was coordinated, this parameter contains the name of the observatory that performed this observation in coordination with NICER.
Galactic HI neutral density in units of cm-2. This value is estimated using the HI 4-pi survey (HP4PI).
The parameter identifies the type of source observed.
Additional remarks concerning the observation.