PLANCK LFI Generate Ancillary Data Sets

Generation of the ancillary data sets needed for the PLANCK LFI science is a major task requiring extensive effort by scientists:

Generation of Ancillary Data Sets

Calibration history and parameters files - absolute and relative
Delays, time constants, frequency response of detectors

intrinsic to front end
due to DC amplifiers
due to integration
due to telemetry sampling and compression scheme

Beam parameters - G(\theta), W(\theta)

central beam properties
far side lobes
beam shape
beam filter function W(\theta) or W(\theta, \phi)
verification and validation of results

Pointing offsets

find the centroid and orientation of each beam and polarization

Noise properties of data - e.g. power spectrum, correlation function, apodization, phase
Systematic effects
Special Signals from planets and other celestial sources

data base of interesting signals and test cases

For PLANCK LFI obtaining and developing these ancillary data sets is critical to the scientific output of the mission but is not in the standard mode in which the bulk of the data will be processed. This effort will require substantial preparation and and effort by knowledgeable. Work will need to be done prior to launch to develop the algorithms, accuracy and precision levels, software and procedures, and then more will be necessary after launch to refine and further develop these data sets.

Development of Ancillary Data Sets

Definition of ancillary data sets

Specify and define needed ancillary data sets
Define required accuracy and precision
Define techniques, algorithms, and procedures
Develop and define ancillary data gathering
Outline ancillary data needs and processes and connect to mission operations
Defined and develop special hardware, links or, software interfaces for ancillary data sets
Are there special diagnostic modes of operation or data?

Specify software development for ancillary data sets

Software and data base definition
Data formats for input and output
Define software, processing procedure and results reporting and exchange
Is special on-board software needed?
How is software verified, validated and delivered?

Produce Ancillary Data Sets or In-Depth Analysis of Ancillary Data Sets

Expert personnel & scientists produce ancillary data set
Investigation of data taken during special operations or sky targets for ancillary data sets
Investigation of data taken for calibration, beam mapping, sources, etc. as a test and check of instrument performance
Follow up of anomalous signals and effects
Development and testing of new software for ancillary data sets
In depth report of ancillary data set results, products, etc.

It is very likely that the data processing center will neither have the manpower or the expertise to provide the ancillary data sets without very significant outside assistance. This is one of the areas in which the US and NASA supported staff can be very valuable to the Planck mission.

Tasks and Roles for Instrument Experts

Definition and Development of Ancillary Data Set requirements
Definition and Development of plans, data taking, algorithms, etc. for Ancillary Data Sets
Software specification and development for Ancillary Data Sets
Provide Expertise and Support for Ancillary Data Set production

Direct production or assistance of ancillary data sets
Interpretation and Review of results of processing for Ancillary data sets
Verification and Validation of Ancillary Data Sets and results
Suggest and Develop ancillary data sets and results based on in-flight results

In-Depth Analysis of Ancillary Data Sets and Products During Operations