Data Set Overview  :   This data set contains Calibrated data taken by New Horizons  Solar Wind Around Pluto  instrument during the PLUTO mission phase.   SWAP comprises electro-optics and detectors to obtain count rate  measurements of the solar wind; measuring the solar wind before,  during and after the Pluto encounter will allow characterization  of the atmospheric escape rate of Pluto. The SWAP electro-optic  elements select the angles and energies of the solar wind and  pickup ions to be measured; ions thus selected are registered with  a coincidence detector system. SWAP measures the energy spectrum  of ions in its environment by varying (also called scanning or  sweeping) voltages of the electro-optics over many steps during a  short time period. SWAP can also immediately follow a sweep of  coarse voltage steps with a sweep of finer steps, centered on the  peak measurement of the coarse sweep, to obtain a higher  resolution of that portion of the energy spectrum.   There are three types of SWAP science data: real-time; summary;  histogram. Real-time data, at rates up to 1Hz, provide the most  detailed science measurements since they contain the full count  rate distribution as a function of energy (speed). For science  summary and science histogram modes, the full distribution is not  recorded. Instead, parameters are derived from the count rate  distribution stored by SWAP. These derived parameters require less  memory than storing the whole distribution. The science summary  and science histogram modes are primarily used during the cruise  phase of the mission. For science data, the common data product is  usually a binary table; for calibrated real-time data,  spectrograms as images are also provided. Typically the tables  have instrument parameters and measurements in the columns and  measurement times in the rows, but the actual format depends on  the type of data and the processing level (raw vs. calibrated).  Other tables containing housekeeping and other parameters are also  provided. This data set includes documentation for all data types  and formats.   During the Pluto Charon Encounter mission phase starting in January,  2015, there were several sub-phases: three Approach sub-phases, (AP1,  AP2 and AP3); a CORE sequence for the Pluto flyby on 14.July, 2015 (Day  Of Year 195), sometimes also referred to as NEP (Near-Encounter Phase);  three Departure sub-phases (DP1, DP2, DP3); a Transition sub-phase  closing out the mission phase in October, 2016. For this final SWAP  delivery for the Pluto mission phase, this data set includes all data  for the Pluto Encounter mission phase, downlinked through late  October, 2016.   SWAP was turned on for nominal operations throughout approach, other  than powering off and on around trajectory correction maneuvers. It was  operating as a ridealong during the PEPSSI plasmarolls, on DOY 107,  115, 121, 128, 148, 156, and 176. There were two other dedicated SWAP  and PEPSSI rolls on DOY 163 and 171. SWAP gain functional testing  occurred on DOY 016 and 137.   Note: Sub-phases AP1, AP2 and AP3 started on 2015-01-15, 2015-04-05  and 2015-06-23, respectively. Sub-phases DP1, DP2 and DP3  started on 2015-07-16, 2015-08-04 and 2015-10-22, respectively.   Every observation provided in this data set was taken as a part of a  particular sequence. A list of these sequences has been provided in  file DOCUMENT/SEQ_SWAP_PLUTO.TAB.  N.B. Some sequences provided may have no corresponding observations.   For a list of observations, refer to the data set index table. This  is typically INDEX.TAB initially in the INDEX/ area of the data set.  There is also a file SLIMINDX.TAB in INDEX/ that summarizes key  information relevant to each observation, including which sequence  was in effect and what target was likely intended for the  observation.    Version  :   This is VERSION 3.0 of this data set.   General statement about data set versions after V1.0  ----------------------------------------------------  The pipeline (see Processing below) was re-run on these data for each  version since the first (V1.0). That will typically change only the  FITS headers but not the FITS data of raw data sets. In some cases  this may change the calibration because the calculated geometry of an  observation has changed. See data set version-specific sections below  for significant exceptions to this general statement, i.e. changes to  pipeline processing, calibration processing, and data delivered.   An all-instrument Calibration Campaign occurred in July 2016. For all  instruments, calibrations were updated as of April 2017 which changed  the data in the calibrated data sets. Calibration changes are described  in the data set version-specific sections.   Note that even if this is not a calibrated data set, calibration  changes are listed as the data will have been re-run and there will be  updates to the calibration files, to the documentation (Science  Operations Center - Instrument Interface Control Document:  SOC_INST_ICD) and to the steps required to calibrate the data.     SWAP updates for Pluto Encounter  Data Sets V3.0  :   This P3 Pluto Encounter dataset release includes all data from the  previous two Pluto deliveries and adds data that was downlinked from  1/31/2016 through 10/31/2016. This dataset completes delivery of all  data covering the Pluto Encounter and subsequent Calibration Campaign.  For SWAP, most of the Pluto Encounter data was downlinked in the 15229  load in August 2015. Since then, SWAP has stayed on and taken data  continuously, other than a few power cycles around spacecraft events  such as 3-Axis operations and trajectory correction maneuvers.   Downlink data several days beyond the end of the nominal end of  mission phase were included in this data set in an attempt to fill out  the products at the nominal end of mission phase; refer to the  CONFIDENCE_LEVEL_NOTE in this data set catalog for more details.   There have been several changes to the PDS data labels, mostly  involving improved values for the NAME, AXIS_NAME, and DESCRIPTION  keywords in ARRAY OBJECTs in SWAP Histogram products. As part of  that work, the count rate HISTOGRAM has been converted to an ARRAY  object to take advantage of the improvements.     SWAP updates for Pluto Encounter  Data Sets V2.0  :   This P2 Pluto Encounter dataset release provides updates to the  Pluto dataset between P1 (data on the ground by 7/31/2015) and P2  (data on the ground by 1/31/2016). All liens from the initial  Pluto delivery have also now been resolved. For SWAP, most of the  Pluto Encounter data was downlinked in the 15229 load in August  2015. Since then, SWAP has stayed on and taken data continuously,  other than a few power cycles around spacecraft events such as  3-Axis operations and trajectory correction maneuvers.    Processing  :   The data in this data set were created by a software data  processing pipeline on the Science Operations Center (SOC) at  the Southwest Research Institute (SwRI), Department of Space Operations. This SOC pipeline assembled data as FITS files from raw telemetry  packets sent down by the spacecraft and populated the data labels  with housekeeping and engineering values, and computed geometry  parameters using SPICE kernels. The pipeline did not resample  the data.    Data  :   The observations in this data set are stored in data files using  standard Flexible Image Transport System (FITS) format. Each FITS  file has a corresponding detached PDS label file, named according  to a common convention. The FITS files may have image and/or table  extensions. See the PDS label plus the DOCUMENT files for a  description of these extensions and their contents.   This Data section comprises the following sub-topics:   - Filename/Product IDs  - Instrument description  - Other sources of information useful in interpreting these Data  - Visit Description, Visit Number, and Target in the Data Labels    Filename/Product IDs  --------------------   The filenames and product IDs of observations adhere to a  common convention e.g.   SWA_0123456789_0X584_ENG.FIT  ^^^ ^^^^^^^^^^ ^^^^^ ^^^\__/  | | | | ^^  | | | | |  | | | | +--File type (includes dot)  | | | | - .FIT for FITS file  | | | | - .LBL for PDS label  | | | | - not part of product ID  | | | |  | | | +--ENG for CODMAC Level 2 data  | | | SCI for CODMAC Level 3 data  | | |  | | +--Application ID (ApID) of the telemetry data  | | packet from which the data come  | | N.B. ApIDs are case-insensitive  | |  | +--MET (Mission Event Time) i.e. Spacecraft Clock  |  +--Instrument designator    Note that, depending on the observation, the MET in the data filename  and in the Product ID may be similar to the Mission Event Time (MET)  of the actual observation acquisition, but should not be used as an  analog for the acquisition time. The MET is the time that the data are  transferred from the instrument to spacecraft memory and is therefore  not a reliable indicator of the actual observation time. The PDS label  and the index tables are better sources to use for the actual timing of  any observation. The specific keywords and index table column names for which to look are   * START_TIME  * STOP_TIME  * SPACECRAFT_CLOCK_START_COUNT  * SPACECRAFT_CLOCK_STOP_COUNT    Instrument Instrument designators ApIDs **  : : :  SWAP SWA 0X584 - 0X587 *   * Not all values in this range are in this data set  ** ApIDs are case insensitive   There are other ApIDs that contain housekeeping values and  other values. See SOC Instrument ICD (/DOCUMENT/SOC_INST_ICD.*)  for more details.    Here is a summary of the types of files generated by each ApID  (N.B. ApIDs are case-insensitive) along with the instrument  designator that go with each ApID:    ApIDs Data product description/Prefix(es)  : :  0x584 - SWAP Science Real-Time/SWA  0x585 - SWAP Science Summary/SWA *  0x586 - SWAP Science Histogram Header/SWA  0x587 - SWAP Science Histogram Data/SWA   * Level 3 NH SWAP data sets produced after April, 2016 do not have  0x585 (Science Summary data); in-flight and in practice, 0x585  data are used only for health and safety and not for science.    Instrument description  ----------------------   Refer to the following files for a description of this instrument.   CATALOG   SWAP.CAT   DOCUMENTS   SWAP_SSR.*  SOC_INST_ICD.*  NH_SWAP_V###_TI.TXT (### is a version number)    Other sources of information useful in interpreting these Data  --------------------------------------------------------------   Refer to the following files for more information about these data   NH Trajectory tables:   /DOCUMENT/NH_MISSION_TRAJECTORY.* - Heliocentric   SWAP Field Of View definitions:   /DOCUMENT/NH_FOV.*  /DOCUMENT/NH_SWAP_V###_TI.TXT   SWAP Data summary plots:   /DOCUMENT/DATA_SUMMARY_PLOTS/SWAP_###DAY_YYYYMMDDHH_#.*     Visit Description, Visit Number, and Target in the Data Labels  ---------------------------------------------------------------   The observation sequences were defined in Science Activity Planning  (SAP) documents, and grouped by Visit Description and Visit Number.  The SAPs are spreadsheets with one Visit Description & Number per row.  A nominal target is also included on each row and included in the data  labels, but does not always match with the TARGET_NAME field's value in  the data labels. In some cases, the target was designated as RA,DEC  pointing values in the form ``RADEC:123.45,-12.34'' indicating Right  Ascension and Declination, in degrees, of the target from the  spacecraft in the Earth Equatorial J2000 inertial reference frame.  This indicates either that the target was either a star, or that the  target's ephemeris was not loaded into the spacecraft's attitude and  control system which in turn meant the spacecraft could not be pointed  at the target by a body identifier and an inertial pointing value had  to be specified as Right Ascension and Declination values. PDS-SBN  practices do not allow putting a value like RADEC:... in the PDS  TARGET_NAME keyword's value. In those cases the PDS TARGET_NAME value  is set to CALIBRATION. TARGET_NAME may be N/A (Not Available or Not  Applicable) for a few observations in this data set; typically that  means the observation is a functional test so N/A is an appropriate  entry for those targets, but the PDS user should also check the  NEWHORIZONS:OBSERVATION_DESC and NEWHORIZONS:SEQUENCE_ID keywords in  the PDS label, plus the provided sequence list (see Ancillary Data  below) to assess the possibility that there was an intended target.  These two keywords are especially useful for STAR targets as often  stars are used as part of instrument calibrations, and are  included as part of the sequencing description which is captured  in these keywords.     Ancillary Data  :   The geometry items included in the data labels were computed  using the SPICE kernels archived in the New Horizons SPICE  data set, NH-X-SPICE-6-PLUTO-V1.0.   Every observation provided in this data set was taken as a part of a  particular sequence. A list of these sequences has been provided in  file DOCUMENT/SEQ_SWAP_PLUTO.TAB. In addition, the  sequence identifier (ID) and description are included in the PDS label  for every observation. N.B. While every observation has an associated  sequence, every sequence may not have associated observations. Some  sequences may have failed to execute due to spacecraft events (e.g.  safing). No attempt has been made during the preparation of this data  set to identify such empty sequences, so it is up to the user to  compare the times of the sequences to the times of the available  observations from INDEX/INDEX.TAB to identify such sequences.    Time  :   There are several time systems, or units, in use in this dataset:  New Horizons spacecraft MET (Mission Event Time or Mission Elapsed  Time), UTC (Coordinated Universal Time), and TDB Barycentric  Dynamical Time.   This section will give a summary description of the relationship  between these time systems. For a complete explanation of these  time systems the reader is referred to the documentation  distributed with the Navigation and Ancillary Information  Facility (NAIF) SPICE toolkit from the PDS NAIF node, (see  http://naif.jpl.nasa.gov/).   The most common time unit associated with the data is the spacecraft  MET. MET is a 32-bit counter on the New Horizons spacecraft that  runs at a rate of about one increment per second starting from a  value of zero at   19.January, 2006 18:08:02 UTC   or   JD2453755.256337 TDB.   The leapsecond adjustment (DELTA_ET : ET - UTC) was 65.184s at  NH launch, and the first three additional leapseconds occurred  in at the ends of December, 2009, June, 2012 and June, 2015.  Refer to the NH SPICE data set, NH-J/P/SS-SPICE-6-V1.0, and the  SPICE toolkit documentation, for more details about leapseconds.   The data labels for any given product in this dataset usually  contain at least one pair of common UTC and MET representations  of the time at the middle of the observation. Other portions  of the products, for example tables of data taken over periods  of up to a day or more, will only have the MET time associated  with a given row of the table.   For the data user's use in interpreting these times, a reasonable  approximation (+/- 1s) of the conversion between Julian Day (TDB)  and MET is as follows:   JD TDB : 2453755.256337 + ( MET / 86399.9998693 )   For more accurate calculations the reader is referred to the  NAIF/SPICE documentation as mentioned above.    Reference Frame  :    Geometric Parameter Reference Frame  -----------------------------------   Earth Mean Equator and Vernal Equinox of J2000 (EMEJ2000) is the  inertial reference frame used to specify observational geometry items  provided in the data labels. Geometric parameters are based on best  available SPICE data at time of data creation.    Epoch of Geometric Parameters  -----------------------------   All geometric parameters provided in the data labels were computed at  the epoch midway between the START_TIME and STOP_TIME label fields.     Software  :   The observations in this data set are in standard FITS format  with PDS labels, and can be viewed by a number of PDS-provided  and commercial programs. For this reason no special software is  provided with this data set.    Contact Information  :   For any questions regarding the data format of the archive,  contact   New Horizons SWAP Principal Investigator:   David McComas, Princeton University   David McComas   Princeton University  Princeton Plasma Physics Laboratory  Peyton Hall  Princeton, NJ 08544  USA

Confidence Level Overview  :  During the processing of the data in preparation for  delivery with this volume, the packet data associated with each  observation were used only if they passed a rigorous verification  process including standard checksums.   In addition, raw (Level 2) observation data for which adequate  contemporary housekeeping and other ancillary data are not available  may not be reduced to calibrated (Level 3) data. This issue is raised  here to explain why some data products in the raw data set,   NH-P-SWAP-2-PLUTO-V3.0,   may not have corresponding data products in the calibrated data set,   NH-P-SWAP-3-PLUTO-V3.0.    Data coverage and quality  :  Every observation provided in this data set was taken as a part of a  particular sequence. A list of these sequences has been provided in  file DOCUMENT/SEQ_SWAP_PLUTO.TAB. N.B. Some sequences  provided may have zero corresponding observations.   Refer to the Confidence Level Overview section above for a summary  of steps taken to assure data quality.   SWAP data product completeness at the end of a mission phase  ------------------------------------------------------------   Downlink data several days beyond the end of the nominal end of  mission phase* were included in this data set in an attempt to fill  the products at the nominal end of mission phase*. This was done in  an attempt to ensure complete coverage of data up through the nominal  end of the mission phase*. This also means that for the SWAP  last-in-time products in this data set, which include observations  beyond the nominal end of the mission phase*, may be incomplete.  The following paragraphs provide details about this issue.   SWAP data product completeness - details  ----------------------------------------   SWAP data are taken more or less continuously, but telemetry downlinks  are done in batches, so the SWAP data are stored on-board the  spacecraft at least until they are downlinked, sometimes hours or days  after they are taken. Furthermore, SWAP PDS data are grouped into  products, each covering approximately one day's worth of data,  starting and ending at a time of day near 18:08 UTC.   This data set comprises data downlinked through a fixed cutoff date*.  The interaction between the downlink cutoff, the batch nature of  downlink, and the grouping of SWAP data will result in the last day's,  or few days', data products in this data set containing less than  a full day's worth of data. This applies to SWAP science and  engineering data as well as housekeeping and thruster data stored in  the data products. This has been most noticeable during the Pluto  PDS data set deliveries, e.g. the last product in the V2.0 delivery  with ApID 0x585 had very little science data and neither housekeeping  nor thruster data, whereas the same product in the V3.0 delivery had  the full expected day's worth of data; also, the V3.0 delivery has a  product with ApID 0x584 that was not present in the V2.0 delivery.   The NH project is considering delivering SWAP data sets as a single  incrementing data set. Beyond that and other than adding a few days  of telemetry beyond the nominal mission phase end*, the NH project has  no further plans to mitigate this minor issue.   In summary, the choice to deliver New Horizon data sets by mission  phase affects SWAP data set product completeness near those mission  phase boundaries.   * Refer to the DATA_SET_DESC or ABSTRACT_DESC of this data set catalog  for the actual final downlink date, and to the mission catalog for  the nominal mission phase boundaries.    Observation descriptions in this data set catalog  :   Some users will expect to find descriptions of the observations  in this data set here, in this Confidence Level Note. This data  set follows the more common convention of placing those  descriptions under the Data Set Description (above, if the user is  reading this in the DATASET.CAT file) of this data set catalog.    Caveat about TARGET_NAME in PDS labels and observational intent  :   The downlink team on New Horizons has  created an automated system to take various uplink products, decode  things like Chebyshev polynomials in command sequences representing  celestial body ephemerides for use on the spacecraft to control  pointing, and infer from those data what the most likely intended  target was at any time during the mission. This works well during  flyby encounters and less so during cruise phases and hibernation.   The user of these PDS data needs to  be cautious when using the TARGET_NAME and other target-related  parameters stored in this data set. This is less an issue for the  plasma and particle instruments, more so for pointing instruments.  To this end, the heliocentric ephemeris of the spacecraft, the  spacecraft-relative ephemeris of the inferred target, and the  inertial attitude of the instrument reference frame are provided  with all data, in the J2000 inertial reference frame, so the user  can check where that target is in the Field Of View (FOV) of the  instrument.   Finally, note that, within the FITS headers of the data products,  the sequence tables, and other NH Project-internal documents used  in this data set and/or inserted into the data set catalog,  informal names are often used for targets instead of the canonical  names required for the TARGET_NAME keyword. For example, during  the Pluto mission phase, instead of the TARGET_NAME '15810 ARAWN  (1994 JR1)' there might be found any of the following: 1994JR1;  1994 JR1; JR1. For all values where the PDS keyword TARGET_NAME  is used (e.g. in PDS labels and in index tables), the canonical,  PDS-approved names are used (if not, please bring this to the  attention of PDS so it can be rectified). However, within the  context of this data set, these project abbreviations are not  ambiguous (e.g. there is only one NH target with 'JR1' in its  name), so there has been, and will be, no attempt to expand such  abbreviations where they occur outside formal PDS keyword values.    Review  :  This dataset was peer reviewed and certified for scientific use on  June 19, 2017.