Quick Links to Observing Tools

ASPRO | BSMEM | CHARA | Keck | VLTI AMBER | VLTI MIDI (MPIA) | VLTI MIDI (ESO)

The editor updated this page on 12 September 2008. As of that date, all the links were active. It might yet be useful to include a standardized description of resources, as can be found for example in the Free Software Directory.

Observation Planning and Calibrator Selection

Keck Interferometer

getCal is an interferometric observation planning software suite: it and its constituent tools can be used to resolve common star names into standard catalog designations and astrometry; extract visibility calibrators from the Hipparcos catalog according to a variety of geometric, brightness, and astrophysical criteria; compute target zenith and delay accessibility; interface with the Simbad astronomical database, the PTI and KI sequencer GUIs, visibility calibration codes, and sky visualization software. getCal also has other uses, is extremely portable, can be autonomously driven over a list of sources, and can be accessed either from either the Unix command line or a (Perl/Tk) GUI.
Web Interface
http://mscweb.ipac.caltech.edu/gcWeb/gcWeb.jsp
Documentation
http://NExSci.caltech.edu/software/getCal/index.html
Support
http://NExSci.caltech.edu/software/
The Visibility Modeling Tool performs visibility predictions for arbitrary brightness maps, uploaded by the user as FITS images. It can perform a detailed calculation of the KI Nuller response. It also allows users to overplot real or simulated interferometer data, uploaded by the user in the OI-FITS format (IAU standard). The VMT 2.0 can be downloaded as a Java executable, or run via a web applet.
Web Interface and Download
http://nexsciweb.ipac.caltech.edu/vmt/vmtWeb/

Very Large Telescope Interferometer

VisCalc, the ESO visibility vs. (u,v)-plane coverage calculator.
CalVin, the ESO online catalog of interferometric calibrator-stars.
SearchCal
SearchCal is the JMMC tool to select the calibrator stars based on the position and properties of the observed target. It allows to define many parameters to get the most efficient calibrator.
Web Interface
http://jmmc.fr/~sclws/SearchCal/SearchCal.jnlp
Documentation
http://www.jmmc.fr/searchcal_page.htm
Support
http://www.jmmc.fr/support.htm
ASPRO-VLTI provides tools to determine the optimal VLTI configuration and interferometric calibrators to achieve the user's astrophysical goals. The optimization is performed through estimating synthetic interferometric observables (visibilities) as well as through fitting theoretical models on these quantities. The fitting process takes into account the measurement errors of the interferometric signal.
Web Interface
http://www.jmmc.fr/aspro_page.htm
Documentation
http://www.jmmc.fr/doc/list.php
Support
http://www.jmmc.fr/support.htm

CHARA Array

A graphical user interface software tool written in the Interactive Data Language (IDL) to help plan interferometric observations with the CHARA Array. The GUI allows the user to select (1) the waveband for the observation, (2) the target HD number from Hipparcos catalog, (3) and angular diameter, (4) a CHARA baseline, (5) the Pipes of Pan "POP" configuration, and (6) date. Numerous ploting options are available. The software calculates for which hour angles the Optical Path Length Compensator delay compensation is possible and also calculates the time of astronomical twilight.
Source Code
http://webfac.db.erau.edu/~aufded93/chara_plan/index.html
Documentation
http://webfac.db.erau.edu/~aufded93/chara_plan/chara_plan_report.pdf
Support
http://webfac.db.erau.edu/~aufded93/

Data Reduction

OYSTER

The name OYSTER was derived from OISDR (Optical Interferometer Script Data Reduction). OYSTER is a 40,000+ lines of code project to provide a comprehensive system for displaying, editing, averaging, calibrating, and modeling interferometry data. It has been developed over several years at the US Naval Observatory. PV-WAVE (a trademark of VNI) CL and IDL (a trademark of RSI) were chosen as the programming environment because they provide interactive data manipulation and extensive plotting and visualization tools. Coding and debugging are very fast in this environment. OYSTER is an endeavor to integrate all tasks related to planning and analysing interferometric observations in one package. It also tries to maximize ease of use by providing both command line procedures and widget routines. A 100-page manual is provided. Users can also find instructions on how to build their own library of procedures which take the place of and modify the implemented procedures by compilation at runtime.
Webpage
http://www.eso.org/~chummel/oyster/oyster.html
Source Code
http://www.eso.org/~chummel/oyster/download.html
Documentation
http://www.eso.org/~chummel/oyster/manual/oyster.html
Support
http://www.eso.org/~chummel/

AMBER

The Astronomical Multi-BEam combineR (AMBER) is one of the instruments which is installed at the focus of the Very Large Telescope Interferometer (VLTI). Details about the AMBER instrument can be found on its home page at LAOG or at ESO. The linked page below provides details and gives access to the download pages of AMBER data processing software.
Webpage
http://www.jmmc.fr/data_processing_amber.htm
Source Code
http://www.jmmc.fr/data_processing_amber.htm
Documentation
http://www.jmmc.fr/data_processing_amber.htm
Support
http://www.jmmc.fr/support.htm

MIDI

MIDI is the mid-infrared interferometric instrument of the VLTI. It is currently offered to the european astronomical community by the European Southern Observatory on a regular basis. Two calls for proposals are issued yearly: one on March 1st and one on September 1st, with submission deadlines one month later. The MIDI Data Reduction Software was developed by the Paris Observatory / LESIA based group of the JMMC.
Webpage
http://www.jmmc.fr/data_processing_midi.htm
Source Code
http://www.jmmc.fr/data_processing_midi.htm
Documentation
http://www.jmmc.fr/data_processing_midi.htm
Support
http://www.jmmc.fr/support.htm

MIDI Interactive Analysis

Software developed at the MPIA to reduce data obtained with MIDI. MIA uses a Fast Fourier Transformation to calculate the Fourier amplitudes of the fringe packets. These amplitudes help to decide, whether a fringe packet can be used to calculate the visibility or not. Please see below what modes can be handled by MIA.
Webpage
http://www.mpia-hd.mpg.de/MIDISOFT/
Source Code
http://www.mpia-hd.mpg.de/MIDISOFT/mia.html
Tutorial
http://www.mpia-hd.mpg.de/MIDISOFT/miatut0.html
Support
http://www.mpia-hd.mpg.de/MIDISOFT/disc.html

VINCI

The detailed description of the implemented algorithms can be found in Kervella et al. (2004, A&A, 425, 1161). This user-friendly software allows to process automatically the raw data from the ESO Archive up to the the squared coherence factor level.
Webpage
http://jmmc.fr/data_processing_vinci.htm
Source Code
http://www.eso.org/%7Epkervell/VINCI_DRS.tar.gz

Model Fitting

LITpro

This software has been developed for the model fitting of data obtained from various stellar optical interferometers and written in the OI Exchange Format. It provides a set of elementary geometrical and center-to-limb darkening functions, all combinable together, which allow to fit Visibilities, Square Visibilities or Triple Products, or any combination of previous observables. It allows to visualize by various plots the data as well as the models and the results of the fits. Tools also have been developed to help users to find the global minimums.
Webpage
http://www.jmmc.fr/litpro
Discussion Forum
http://listes.ujf-grenoble.fr/wws/info/jmmc-litpro-users

Imaging Data Analysis

BSMEM

The Cambridge software package for image reconstruction from optical interferometry data has been dubbed BSMEM, to stand for BiSpectrum Maximum Entropy Method. BSMEM applies a fully Bayesian approach to the inverse problem of finding the most probable image given the evidence. BSMEM makes use of the MemSys library created by Maximum Entropy Data Consultants Ltd. to implement a gradient descent algorithm for maximising the inference (posterior probability) of an image, using the entropy of the reconstructed image as the prior probability. From 2002 to 2006, while the core of the program has remained more or less unchanged, multiple improvements have been implemented by Hrobjartur Thorsteinsson and Fabien Baron. BSMEM has partly been ported to C, it has gained compatibility with the OIFITS format, and the reconstruction options and the user interface have been improved and expanded. BSMEM contains proprietary software, but is available for academic use subject to a no-fee licence agreement. To obtain BSMEM, go to the BSMEM website, download the licence agreement, print it out, sign it, and mail the signed copy as per the instructions, to Maximum Entropy Data Consultants Ltd. You can then contact John Young to obtain the software.
Webpage
http://www.mrao.cam.ac.uk/research/OAS/bsmem.html
Support
http://www.mrao.cam.ac.uk/~jsy1001/

MiRA

MiRA is an algorithm for image reconstruction from data provided by optical interferometers. MiRA proceeds by direct minimization of a penalized likelihood. This penalty is the sum of two terms: a likelihood term which enforces agreement of the model with the data, plus a regularization term to account for priors. The priors are required to lever the many degeneracies due to the sparseness of the spatial frequency sampling. MiRA implements many different regularizations (quadratic or edge-preserving smoothness, total variation, maximum entropy, etc.) and let the user defines his own priors. The likelihood penalty is modular and designed to account for available data of any kind (complex visibilities, powerspectra and/or closure phase). One of the strength of MiRA is that it is purely based on an inverse problem approach and can therefore cope with incomplete data set; for instance, MiRA can build an image without any Fourier phase information.
Webpage
http://www-obs.univ-lyon1.fr/labo/perso/eric.thiebaut/mira.html
Support
http://www-obs.univ-lyon1.fr/labo/perso/eric.thiebaut/index.html

MACIM

The MArkov Chain Imager (MACIM) is a publically-available Monte Carlo imaging algorithm. Currently, only the C code is publically released, and should run under any Unix system (including Mac OS X). The README file in this distribution contains a little information on how to run the code, but you'll have to see the SPIE paper for details. In order to display the fits images and chi-squared while running MACIM, use the IDL procedure display_macim. This uses a library function (modified from the standard IDL distribution) image_cont.
Webpage
http://www.physics.usyd.edu.au/~mireland/publications.html
Support
http://www.physics.usyd.edu.au/~mireland/

WISARD

Webpage
http://www.onera.fr/dota-en/wisard/index.php
Source
http://eii-jra4.ujf-grenoble.fr/wizard.html
Support
http://www.jmmc.fr/support.htm
YouTube
Reconstruction d'image astronomiques, Serge Meimon

OIFITS Format

OIFITS Format Specification

The OI Exchange Format is a standard for exchanging calibrated data from optical (visible/infrared) stellar interferometers. The standard is based on the Flexible Image Transport System (FITS), and supports storage of the optical interferometric observables including squared visibility and closure phase -- data products not included in radio interferometry standards such as UV-FITS.
A data exchange standard for optical (visible/IR) interferometry

T.A. Pauls, J.S. Young, W.D. Cotton, and J.D. Monnier

Pub. Astron. Soc. Pac.117, 1255-1262 (2005).
Webpage
http://www.mrao.cam.ac.uk/~jsy1001/exchange/
Support
http://www.mrao.cam.ac.uk/~jsy1001/

IDL Utilities

An IDL library designed to read and write optical interferometry data conforming to the OI-DATA standard. All features of the OI-DATA format are supported, including the ability to read and write multiple OI-ARRAY, OI-WAVELENGTH, OI-VIS, OI-VIS2, and OI-T3 binary tables. This makes merging data from different epochs and arrays straightforward. Using read_oidata.pro and write_oidata.pro, one should be able to easily use OI-DATA in the IDL data analysis environment.
Webpage
http://www.astro.lsa.umich.edu/~monnier/oi_data/index.html
Support
http://www.astro.lsa.umich.edu/~monnier/

Examples in C

The software is intended as a demonstration of how to write code to read and write files in the exchange format. You may nevertheless find it useful to use the routines provided without modification. The software is written in ANSI C, and uses the cfitsio library.
Source Code
ftp://ftp.mrao.cam.ac.uk/pub/jsy1001/exchange/
Documentation
ftp://ftp.mrao.cam.ac.uk/pub/jsy1001/exchange/html/index.html
Support
http://www.mrao.cam.ac.uk/~jsy1001/

1. Observation Planning

Scheduling, UV tracks, binary orbits, visibility prediction, calibrator selection. Data simulators should probably go in this category as well.

2. Data Reduction

Software involved in converting raw fringe data to possibly averaged but UNCALIBRATED or partially-calibrated data products (squared visibilities, bispectra etc.) Software in this category need only be listed if the interferometer/instrument is or will be available to the community (or a subset)

3. Calibration

Calibration of the output from (2), to give the final calibrated data products.

4. Imaging Data Analysis

Imaging and model-fitting using calibrated, averaged data products

5. Astrometric Data Analysis

Astrometric analysis of the output of any of (2), (3), or (4).

6. Utilities

Software applications that perform small, well-defined OI-specific tasks, but do not fit into any one of the above categories.

7. Software Libraries

OI-specific subroutine libraries applicable to more than one of the previous categories.

Caltech VLBI Analysis Programs

The Caltech VLBI Analysis Programs, CITVLB, were written for radio very long baseline interferometry. The package contains a large number of separate Fortran programs that are used sequentially for data display, calibration and editing, model-fitting, and imaging. Self-calibration is possible using either CLEAN or MEM for the deconvolution. Data is read into the programs in MERGE format, and the suite of software includes programs to translate data into MERGE format from other formats, notably UVFITS - the standard data format for radio interferometry. CITVLB was supported by Tim Pearson at Caltech, until the software was superseded by DIFMAP around 1995. The programs assumed that a small number of telescopes were used in the array, and the data was limited to single-frequency and single-polarization data. These limitations, which ultimately halted the development of CITVLB, made the programs particularly well suited to optical interferometry, where small single-frequency data sets are typical. It broke the data processing into simple steps, allowing easy inspection of the data at each step, and providing greater quality control. CITVLB was used by the group at the Cavendish Laboratory in aperture masking experiments, and in long-baseline measurements with the COAST interferometer. Haniff 1992 used this (MEM and CLEAN) for observations of Mira. It is worth noting that CITVLB contains a program called VLBMEM, which was written by S.F. Gull in 1989. This VLBMEM is a stand-alone program that performs only the MEM deconvolution, and requires other CITVLB programs to complete a self-calibration loop.
The UVFITS format is described in Going AIPS A Programmer's Guide to the NRAO Astronomical Image Processing System, Chapter 14 "FITS TAPES", pages 14.7 to 14.10 (1990).
MERGE format is described in Introduction to the Caltech VLBI Programs, Chapter 11 "Format of MERGE Files", pages 11.1 to 11.4 (1991).

Summary of Resources

The following summaries are not current, even though the previous section are up to date. I will update this summary as time permits. - PRL 2008/09/12.

Group
Wavelengths
Calibrator Catalog
Software Tools
Documentation
CHARA
H,K
None
NA
NA
COAST
V,H
None
mfit
Exchange format
FLUOR
K
URL, ASCII, Excel, readme
NA
Software and Manual
ISI
N
None
NA
NA
Keck
K
NA
getCal
KI Support
MIDI
L
Calvin
MIDISOFT
NA
MIRA
V
NA
NA
NA
NPOI
V
ASCII
STARWHEEL (Oyster)
Oyster
PTI
K
van Belle et al. 2008
getCal
KI Support
SUSI
V
None
NA
NA
VLTI
K,N
Calibrators/CALVIN
VisCalc (Previews)
SimVLTI
FRINGE
-
NA
MC3D
Download site
JMMC
-
NA
ASPRO

JMMC
-
NA
VINCI

MSC
-
NA
MSC Software
Download site
J. Monnier
-
NA
IDL Routines
Data Exchange Format

Group
Wavelengths
Calibrator Catalog
Software Tools
Documentation
FLUOR
K



GI2T
V



IONIC
H



IOTA
H, K



MIDI
L
Calvin / SearchCal
MIDISOFT
ASPRO (preparation)
?????
VLTI
K,N
Calibrators/CALVIN
VisCalc (Previews)
ASPRO
SimVLTI
Here( Aspro )
FRINGE
-
NA
??
??
AMBER
(J) H K
Calibrators:
SearchCal
Data reduction:
amdlib(data reduction)
Here
JMMC
K
NA
Data reduction:
VINCI
Here
JMMC
-
SearchCal
Observation Preparation:
ASPRO
Here
Updated 12 September 2008