2024/06/03 Status of MEA L1 data CDF files
MEA L1 datasets
We are now using the required file naming pattern :
mmo_mppe-mea[1/2]_<dataset>_<yyyymmdd>_v<version>.cdfList of mppe-mea1 datasets:
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3D data in [high/med/low] resolution:
mmo_mppe-mea1_l1_3d-low_yyyymmdd_v00.cdf mmo_mppe-mea1_l1_3d-med_yyyymmdd_v00.cdf mmo_mppe-mea1_l1_3d-high_yyyymmdd_v00.cdf -
Omni-directional data [16/32/64] energies:
mmo_mppe-mea1_l1_omni-16e_yyyymmdd_v00.cdf mmo_mppe-mea1_l1_omni-32e_yyyymmdd_v00.cdf mmo_mppe-mea1_l1_omni-64e_yyyymmdd_v00.cdf -
Pitch-angle products:
mmo_mppe-mea1_l1_pap-2s_yyyymmdd_v00.cdf mmo_mppe-mea1_l1_pap-4s_yyyymmdd_v00.cdf mmo_mppe-mea1_l1_pap-16s_yyyymmdd_v00.cdf -
Onboard velocity moments [low/med] resolution:
mmo_mppe-mea1_l1_vm-low_yyyymmdd_v00.cdf mmo_mppe-mea1_l1_vm-med_yyyymmdd_v00.cdf -
Houskeeping [MEA/system]:
mmo_mppe-mea1_l1_hsk_yyyymmdd_v00.cdf mmo_mppe-mea1_l1_sys-hsk_yyyymmdd_v00.cdf
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Same datasets are available for mmo_mppe-mea2. |
Metadata description for MEA1 2023-06-19 CDF files can be found at /documents/SKELETONS/TXT
Common metadata
All our datasets have a common set of CDF varibles :
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epoch (CDF_TT200)
Center or acquisition interval
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delta_epoch (CDF_REAL4)
Half-interval length (seconds)
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mdp_ti (CDF_UINT4)
Number of ticks since last reboot (1/512 s)
Notes
We are using the Jaxa libsctimcal to compute epoch CDF_TT2000 values from mdp_ti clock values :
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by direct calls from C language to libsctimcal.so
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with a binding to libsctimecal.so for python language
We are not using delta_epoch1, delta_epoch2 as they are by definition the same:
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epoch.DELTA_PLUS_VAR = delta_epoch
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epoch.DELTA_MINUS_VAR = delta_epoch
Currently, we are using a constant spin duration = 4s.
Out datasets are centered on the epoch value, with a delta_epoch = 2s
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Where to find the real spin duration after MMO/MPO separation? Are there some auxilliary files that will give the information |
Discrepancies
We are not yet able to handle CDF L1 version with major, minor (v<major>.<minor>)
We are thinking to register the <major> version in our master CDF skeletons files, and increase it when modifying the structure of each datasets.
We will have then to create some datasets catalog to take in account the various deliverires of our CDF files.
Currently, all of our CDF have a v00 version number.
CDF standards compliance
All of our CDF datasets represent an unique time-serie, with a single time-varible (epoch + delta_epoch)
All other measurements are record-varying CDF zVariables, with a DEPEND_0 = epoch attribute
We have started to feed in as many as possible attributes to provide ISTP compliance, and are open to any mandatory metadata updates to ensure compatibility with other needed standards, or to facilitate further automated PDS4 label generation.
All comments are welcome and we can easily update and reprocess MEA L1 CDF files for the whole mission.
MEA L2 CDF data
We have currently provided MEA L1 CDF files, but are planning to deliver soon the first MEA L2 CDF files.
MEA L2 dataset are not yet finalized, but we are planning to provide MEA L2 datasets computed from corresponding L1 datasets, with the same data structure but in physical units.
Main MEA L2 datasets, that will be provided as soon as possible:
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3D data in [high/med/low] resolution:
mmo_mppe-mea1_l2_3d-low_yyyymmdd_v00.cdf mmo_mppe-mea1_l2_3d-med_yyyymmdd_v00.cdf mmo_mppe-mea1_l2_3d-high_yyyymmdd_v00.cdf -
Omni-directional data [16/32/64] energies:
mmo_mppe-mea1_l2_omni-16e_yyyymmdd_v00.cdf mmo_mppe-mea1_l2_omni-32e_yyyymmdd_v00.cdf mmo_mppe-mea1_l2_omni-64e_yyyymmdd_v00.cdf
We can also provide MEA1 ground-computed velocity moments, from both 3D on omni-directional L1 data:
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mmo_mppe-mea1_l2_moments-3D_yyyymmdd_v00.cdf
mmo_mppe-mea1_l2_moments-omni_yyyymmdd_v00.cdfThese data are computed by Mathias Rojo from IRAP, but have to be splitted in daily CDF files.
In a second step, we should also provide the folowwing datasets:
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Pitch-angle products
mmo_mppe-mea1_l2_pap-2s_yyyymmdd_v00.cdf mmo_mppe-mea1_l2_pap-4s_yyyymmdd_v00.cdf mmo_mppe-mea1_l2_pap-16s_yyyymmdd_v00.cdf -
Onboard velocity moments
mmo_mppe-mea1_l2_vm-low_yyyymmdd_v00.cdf mmo_mppe-mea1_l2_vm-med_yyyymmdd_v00.cdf
Data processing pipeline
We would like to provide directly MEA L2 data to Mio Science Center, adding all needed metadata attributes, without producing intermediate l1p CDF files.
We just need to get the list of attributes the MIO science center is planning to add to convert from L1P to L2.
We are also OK to add in our L1/L2 CDFs any attribute that can bee needed to allow automated feed in of further PDS4 labels.
To be discussed
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How to deliver MEA data to MIO science center?
Currently, we can only deliver files to the reformater computer at ISAS
Is there a dedicated procedure to deliver data.
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Do we have to deliver MEA L1 data to MIO center?
