Thursday 16 July 2015, by Baptiste Cecconi
There are six categories of metadata included into RadioJOVE CDF files, as presented below.
The ISTP (International Solar Terrestrial Program) global attributes are required for CDF archiving either in the HPDE (Heliophysics Data Environment) or PDS4 (NASA Planetary Data System version 4) context. The list of ISTP global attributes is given on the following table.
| Attribute Name | Description | Example for RadioJOVE/Dual Channel Spectrograms |
|---|---|---|
| Project | This attribute identifies the name of the project and indicates ownership. (Required by ISTP) | RadioJOVE |
| Source_name | This attribute identifies the mission or investigation that contains the sensors. (Required by ISTP) | RadioJOVE |
| Discipline | This attribute describes both the science discipline and sub discipline. (Required by ISTP) | Planetary Physics>Magnetospheric Science |
| Data_type | This attribute identifies the data type of the CDF data set. Both a long name and a short name are given. (Required by ISTP) | EDR>Experiment Data Record |
| Descriptor | This attribute identifies the name of the instrument or sensor that collected the data. (Required by ISTP) | sp2_300>Dual Channel Spectrogram with 300 frequency steps |
| Data_version | This attribute identifies the version of a particular CDF data file. (Required by ISTP) | 07 |
| Logicle_file_id | This attribute stores the name of the CDF file using the ISTP naming convention (source_name / data_type / descriptor / date / data_version). (Required by ISTP) | radiojove_edr_sp2_300_201412020800_201412021059_v07 |
| PI_name | This attribute value should include first initial and last name. (Required by ISTP) | D. Typinski |
| PI_affiliation | This attribute value should include a recognizable abbreviation. (Required by ISTP) | RadioJOVE |
| TEXT | This attribute is an NSSDC standard global attribute which is a text description of the experiment whose data is included in the CDF. (Required by ISTP) | RadioJOVE Project data. |
| Instrument_type | This attribute is used to facilitate making choices of instrument type through CDAWeb. More than one entry is allowed. (Required by ISTP) | Spectrogram Receiver |
| Mission_group | This attribute has a single value and is used to facilitate making choices of source through CDAWeb. (Required by ISTP) | RadioJOVE |
| Logical_source | This attribute carries source_name, data_type, and descriptor information. (Required by ISTP) | radiojove_edr_sp2_300 |
| Logical_source_description | This attribute writes out the full words associated with the encrypted Logical_source above. (Required by ISTP) | RadioJOVE Dual Channel Spectrograph |
| File_naming_convention | If a global attributed named "File_naming_convention" exists, its value and pattern are used to construct the leading portion of the output file name. If not the "Logical_source" attribute is used. (Optional by ISTP) | source_descriptor_yyyyMMddHHmm_yyyyMMddHHmm_V05 |
| Software_version | This is a text attribute containing the processing software version number. (Optional by ISTP) | 0.5 |
| Skeleton_version | This is a text attribute containing the skeleton file version number. (Optional by ISTP) | 0.5 |
| Generated_by | This attribute allows for the generating data center/group to be identified. (Recommended by ISTP) | SkyPipe RadioJOVE VOPDC |
| Generation_date | Date stamps the creation of the file. (Recommended by ISTP) | Wed Jun 3 23:45:42 2015 |
| LINK_TEXT | This attribute stores text describing on-line data available at PI or CoI web sites. (Recommended by ISTP) | Radio-SkyPipe Software webpage RadioJOVE webpage VOParis Data Centre webpage |
| LINK_TITLE | This attribute stores the title of the web site holding on-line data available at PI or CoI web sites. (Recommended by ISTP) | Radio-SkyPipe Software RadioJOVE VOParis Data Centre |
| HTTP_LINK | This attribute stores the URL for the PI or CoI web site holding on-line data. (Recommended by ISTP) | http://www.radiosky.com/skypipeishere.html http://radiojove.gsfc.nasa.gov http://voparis-europlanet.obspm.fr |
Guidelines to build ISTP global attributes are provided here.
The PDS4 global attributes may vary depending on the dataset. The definitive list is defined by the PDS review panel, at the time of the review of the dataset archival process. The list of proposed PDS4 global attributes are described in the following table.
| Attribute Name | Description | Example for RadioJOVE/Dual Channel Spectrograms |
|---|---|---|
| PDS_Observation_start_time | ISO formatted observation start UTC time | 2014-12-02T08:00:00.108.924.508.096Z |
| PDS_Observation_stop_time | ISO formatted observation stop UTC time | 2014-12-02T10:59:59.927.070.736.883Z |
| PDS_Observation_target | This attribute contains the named observation target. | Jupiter |
| PDS_Observation_type | This attribute contains the type of observations. | Waves |
NB1: The PDS4 global attributes are composed with a "PDS_" prefix.
NB2: The lists of allowed values for "PDS_Observation_target" and "PDS_Observation_type" attributes are being defined by PDS.
The VESPA global attributes have been added to the dataset in order to facilitate its distribution using the VESPA VO interface. The List of VESPA global attributes are given in the following table.
| Attribute Name | Description | Example for RadioJOVE/Dual Channel Spectrograms |
|---|---|---|
| VESPA_dataproduct_type | This attribute provides the VESPA data product type, as defined by VESPA. | DS>Dynamic Spectra |
| VESPA_target_class | This attribute contains the class of the target, as defined by VESPA. | planet |
| VESPA_target_region | This attribute contains the observed target region. | Aurora |
| VESPA_target_element | This attribute contains the named observed target element. | Io-A DAM |
| VESPA_time_min | This attribute contains the observation start UTC time, expressed in Julian Day. | 2456993.833334594 |
| VESPA_time_max | This attribute contains the observation stop UTC time, expressed in Julian Day. | 2456993.9583324892 |
| VESPA_time_sampling_step_min | This attribute contains the minimum value of the temporal sampling step in seconds. | 0.15690923 |
| VESPA_time_sampling_step_max | This attribute contains the maximum value of the temporal sampling step in seconds. | 0.15694946 |
| VESPA_spectral_range_min | This attribute contains the lower bound of observed spectral range (in Hz) . | 1.6053333E7 |
| VESPA_spectral_range_max | This attribute contains the upper bound of observed spectral range (in Hz) . | 3.2E7 |
| VESPA_instrument_host_name | This attribute contains the name of the observatory or spacecraft hosting the instrument. | AJ4CO DPS |
| VESPA_instrument_name | This attribute contains the name the instrument. | RadioJOVE Dual Channel Spectrograph |
| VESPA_measurement_type | This attribute contains the type of physical parameter measured, using UCD, as defined by IVOA. | phys.flux;em.radio |
| VESPA_access_format | This attribute contains the data format. | cdf |
NB1: The VESPA global attributes are composed with a "VESPA_" prefix.
NB2: The lists of allowed values for "VESPA_dataproduct_type" and "VESPA_target_class" attributes are given in EPN-TAP documentation.
The RadioJOVE global attributes are describing RadioJOVE specific aspects. The List of RadioJOVE global attributes are given in the following table.
| Attribute Name | Description | Example for RadioJOVE/Dual Channel Spectrograms |
|---|---|---|
| RadioJOVE_observer_name | This attribute provides name of the observer. | Dave Typinski |
| RadioJOVE_observatory_location | This attribute provides name of location observatory. | High Springs, FL |
| RadioJOVE_observatory_latitude | This attribute provides latitude of the observatory, in degrees. | 29.836944580078125 |
| RadioJOVE_observatory_longitude | This attribute provides longitude of the observatory, in degrees. | 82.62139129638672 |
| RadioJOVE_dipole_orientation_angle | This attribute provides orientation of the RadioJOVE dipoles, in degrees. This is a vector, with as many values as there are channels connected to antennas. Zero value corresponds to a meridian orientation (North-South). | 0.0, 90.0 |
| RadioJOVE_original_filename | his attribute provides original file name (if applicable). | AJ4CO-141201080000.sps |
| RadioJOVE_n_channel | his attribute provides number of channels connected to antennas. | 2 |
The ISTP variable attributes are required for CDF archiving either in the HPDE or PDS4 context. The list of ISTP variable attributes is given on the following table.
| Attribute Name | Description | Example for RadioJOVE/Dual Channel Spectrograms |
|---|---|---|
| CATDESC | Plain text description of the variable. | Data stream on Channel 1 |
| DEPEND_0 | Variable name that shall be used to ordre data on Axis 0 | Epoch |
| DEPEND_1 | Variable name that shall be used to ordre data on Axis 1 (if present) | FREQUENCY |
| DISPLAY_TYPE | Tells automated software what type of plot to make and what associated variables in the CDF are required in order to do so | spectrogram |
| DICT_KEY | Data dictionary keyword list and describes the variable to which it is attached. The ISTP/IACG standard dictionary keyword list is described in ISTP/IACG Dictionary Keywords. | electric_field> |
| FIELDNAM | Short name (no space) used for cross-reference inside the file | DATA_1 |
| FILLVAL | Number inserted in the CDF in place of data values that are known to be bad or missing | -1.0E31 |
| FORMAT | Fortran-type code format for numerical data display | F8.3 |
| LABAXIS | Label to be displayed along the amplitude axis. | Power Spectral Density on Channel 1 |
| UNITS | Unit of the variable | W/m^2/Hz |
| MONOTON | indicates whether the variable is monotonically increasing or monotonically decreasing (optional). Recommended for axis variables, such as temporal or spectral axis. | (N/A) |
| SCALEMIN | Value which can be based on the actual values of data found in the CDF data set or on the probable uses of the data. Visualization software can use these attributes as defaults for plotting. The values must match the data type of the variable | 0 |
| SCALEMAX | Value which can be based on the actual values of data found in the CDF data set or on the probable uses of the data. Visualization software can use these attributes as defaults for plotting. The values must match the data type of the variable | 5000 |
| VALIDMIN | Minimum value for a particular variable that are expected over the lifetime of the mission. The value must match the data type of the variable. | 0 |
| VALIDMAX | Maximum value for a particular variable that are expected over the lifetime of the mission. The value must match the data type of the variable. | 5000 |
| VAR_TYPE | identifies a variable as either: data (integer or real numbers that are plottable); support_data (integer or real "attached" variables); metadata (labels or character variables); ignore_data (placeholders). |
data |
| SCALETYP | indicates if the variable should have a linear or a log scale as a default. | lin |
A complete list of ISTP variable attributes are provided here.
In order to share the data through VESPA, a few IVOA variable attributes must be present. The List of IVOA variable attributes are given in the following table.
| Attribute Name | Description | Example for RadioJOVE/Dual Channel Spectrograms |
|---|---|---|
| UCD | Unified Content Descriptor | phys.flux;em.radio |
The RadioJOVE team provides several data products. They can be grouped by data product type (dataproduct_type, as defined by VESPA, see above): time series and dynamic spectra.
There are 2 types of time series: raw waveforms and amplitude time series. The latter is derived from the former. The Radio SkyPipe software used by RadioJOVE observers can deal with up to 8 parallel channels. The following table gives the various time series data products and their associated CDF skeleton.
| Logical_source | Description | CDF Skeleton for RadioJOVE |
|---|---|---|
| radiojove_edr_ts1 | 1-channel time series of raw waveform | SKT |
| radiojove_edr_ts2 | 2-channel time series of raw waveform | SKT |
| radiojove_edr_ts3 | 3-channel time series of raw waveform | SKT |
| radiojove_edr_ts4 | 4-channel time series of raw waveform | SKT |
| radiojove_edr_ts5 | 5-channel time series of raw waveform | SKT |
| radiojove_edr_ts6 | 6-channel time series of raw waveform | SKT |
| radiojove_edr_ts7 | 7-channel time series of raw waveform | SKT |
| radiojove_edr_ts8 | 8-channel time series of raw waveform | SKT |
| radiojove_ddr_ts1 | 1-channel time series of derived amplitude | SKT |
| radiojove_ddr_ts2 | 2-channel time series of derived amplitude | SKT |
| radiojove_ddr_ts3 | 3-channel time series of derived amplitude | SKT |
| radiojove_ddr_ts4 | 4-channel time series of derived amplitude | SKT |
| radiojove_ddr_ts5 | 5-channel time series of derived amplitude | SKT |
| radiojove_ddr_ts6 | 6-channel time series of derived amplitude | SKT |
| radiojove_ddr_ts7 | 7-channel time series of derived amplitude | SKT |
| radiojove_ddr_ts8 | 8-channel time series of derived amplitude | SKT |
The Radio SkyPipe software used by RadioJOVE observers produces single or dual channel spectrograms with 200, 300 or 400 frequencies. The following table gives the various time series data products and their associated CDF skeleton.
| Logical_source | Description | CDF Skeleton for RadioJOVE |
|---|---|---|
| radiojove_edr_sp1_200 | Single antenna spectrogram with 200 frequencies | SKT |
| radiojove_edr_sp1_300 | Single antenna spectrogram with 300 frequencies | SKT |
| radiojove_edr_sp1_400 | Single antenna spectrogram with 400 frequencies | SKT |
| radiojove_edr_sp2_200 | Dual antenna spectrogram with 200 frequencies | SKT |
| radiojove_edr_sp2_300 | Dual antenna spectrogram with 300 frequencies | SKT |
| radiojove_edr_sp2_400 | Dual antenna spectrogram with 400 frequencies | SKT |