Data acquisition, distillation,
and storage
FASR will produce ~10 Tbyte/day at
maturity
•
• “Raw” data products include visibility data,
M&C data, calibration data, data quality
flags
Data path from instrument to users/archive
depends …
End-to-end Data Flow (?)
ALMA Software
ALMA Specifications
Antennas
64 x 12 m
Collecting area
>7000 m2
Resolution
0”.02 λmm*
FOV
20”λmm
Receivers
10 bands: 0.3 – 7 mm
(36 - 850 GHz)
Correlator
2016 baselines
Bandwidth
16 GHz/baseline
Spectral
channels
*configuration dep.
4096 per IF (8 x 2 GHz)
ALMA Software Effort
‹
‹
‹
Approximately 50 people
NRAO
ESO, MPIfR
IRAM, LERMA, CSIC
UKATC, UMIST
HIA
JCMT
5 Year Project – mid-2002 to mid-2007,
construction phase only
230 FTE Years
ALMA Software Components
‹
‹
Operating Systems
Linux RedHat
VxWorks
RTAI
Windows supported for
Java applications
Packages
ACS
AIPS++
Various astronomy libraries,
TPoint, SLALIB, etc.
‹
Languages
Java
C++/C
Python
ALMA Software Infrastructure
‹
ACS provides:
• CORBA-based distributed intra-computer, multilingual interface
• Remote function invocation
• Event channels
• Monitor data encapsulation (“properties”)
• Error tracing and logging
• Time
• Encapsulation of third-party libraries, e.g., FITS,
astronomy libraries.
Software Subsystems
Proposal Preparation
Proposal Preparation (Phase I)
Program Preparation (Phase II)
Scheduling Block Output
Scheduler
Determines ‘best time’ to execute
a program based on weather,
array configuration, etc.
Doles out SB’s to Control
Control
Configures array for scans
Monitors antennas & all
electronics except correlator.
Correlator
Control & monitor correlator
hardware
Process raw correlator output
delivering to Archive, Tel
Cal., QL pipeline
Telescope Calibration
Performs focus, pointing, phase,
amplitude, & WVR
calibrations
Pipelines
Quick Look
Off-line
AIPS++
Data Reduction User Interface
Software Subsystems (2)
Executive
High-level monitoring
Observatory Administration
Archive
Holds all intermediate & final
data products
Internal format VOTable
Output formats: VOTable, FITS
Quality Control
Short term ‘correctness’ of
observation
Monitor long term changes of
observatory
Science Software Requirements
Map ALMA science goals to
software requirements
High Level Analysis
Develop high-level design and
framework for all
subsystems
Integration & Test
Monthly integration builds
Semi-annual releases x.0 & x.1
Develop and execute system
tests
Software Engineering
Sets development tool
standards
Defines and monitors
development processes
NVO/
EGSO
NVO/
EGSO
o The instrument “product” is the archive
o The archive contains all instrument data
(visibility, calibration, M&C, data quality)
o The archive may be permanent or interim
– if the latter, data selection, distillation,
and reduction result in a final suite of data
and data products that are permanently
archived.
o User interaction with the instrument is
through the archive
o “GI observing” may simply take the form
of funded data analysis – user defines data
selection criteria and data products
o Define software requirements!
o Science simulations!
o Assess manpower requirements
- scientists
- pros
- management?
o Language(s)
o Community input!
What
Next?