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II/345         JMDC : JMMC Measured Stellar Diameters Catalogue   (Duvert, 2016)

Compendium of Direct Measurement of Apparent Stellar Diameters. (Introduced as part of Chelli et al., 2016A&A...589A.112C). Duvert G. <JMMC center (2016)> =2016yCat.2345....0D
ADC_Keywords: Stars, diameters Keywords: stars: fundamental parameters - techniques: data analysis - techniques: interferometric - astronomical database: miscellaneous - catalogs Abstract: This catalog lists all measurements of stellar apparent diameters made with "direct" techniques: optical interferometry, intensity interferometry and lunar occultations that have been published since the first experiments by Michelson. Description: Several star diameter compilations exist that contain a fair amount of stellar angular diameter measurements. The CADARS (2011, Cat. II/224) has entries for 6888 stars and claims completeness up to 1997. CHARM2 (2005, Cat. J/A+A/431/773) lists 8231 measurements of 3243 stars, up to 2005. However all these catalogs mix results from very direct methods, such as intensity interferometry, with indirect methods, or spectrophotometric estimates of various kind (always including some model of the star), or linear diameters from eclipsing binaries (1600 entries in CADARS), which need some modelling of the two stars, as well as a good estimate of the distance to be converted into an angular diameter. In contrary, the present catalogue, called JMDC (for JMMC Measured stellar Diameters Catalog) is focussed on direct methods only, and selects only one value of the uniform-disk diameter (UDD) and limb-darkened diameter (LDD) for each historical measurement. It should be regularly updated via a specialized submission tool that will be made available on the JMMC website ( The current version gathers 1478 measurements that have been published since the first experiments by Michelson. Prior to 1997, our bibliography relies only on the reference list of CADARS, carefully reviewed. After this date we used NASA's ADS hosted at CDS. We retained only the measurements obtained from visible/IR interferometry, intensity interferometry and lunar occultation in the database. We always retrieved the values in the original text and used SIMBAD to properly and uniquely identify the stars. The three techniques retained share the same method of converting the measurements (squared visibilities for optical interferometry, correlation of photon-counts for intensity interferometry, fast photometry for lunar occultations) into an angular diameter: fitting a geometrical function into the values, in many cases a uniform disk, which provides a uniform disk diameter (UDD) value. This UDD is wavelength-dependent owing to the limb-darkening effect of the upper layers of a star's photosphere, and JMDC retains the wavelength or photometric band at which the observation was made. To measure a star's apparent diameter consistently, i.e., with the same meaning as our Sun's well-resolved apparent diameter, it was necessary for the authors of these measurements to take into account the star's limb-darkening, for which only theoretical estimates exist as yet. They chose one of the various limb-darkening parameters available in the literature, either by multiplying the UDD by a coefficient function of the wavelength and the star's adopted effective temperature, or directly fitting a limb-darkened disk model in the data. Of course this adds some amount of theoretical bias in the published measurements, which however diminishes as the wavelength increases. An additional difficulty for the lunar occultations is that the result depends on the exact geometry of the occulting portion of the lunar limb, which can, more or less, be correctly estimated. To deal with the limb-darkening problem as efficiently as possible, in the publications where reported diameters are measured in several optical/IR bands, we retain the measurement with the best accuracy and favor the measurement at the longest wavelength to minimize the effect of limb-darkening correction. When the publication include both LDD and UDD values, we report both, and, if available, the conversion coefficient used. We provide in the Notes additional information, such as the eventual binarity of the star, possible erroneous measurements, origin the of limb-darkening factor used, duplication with other publications etc... as weel as more "in-house" comments related to the proper use of this database in the companion publication 2016A&A...589A.112C. In the paper 2016A&A...589A.112C, we further use the published UDD measurement, or retrieve the original, unpublished UDD measurement from the LDD value and the limb-darkening coefficient used by the authors. We then convert these UDD values into limb-darkened angular diameters using mainly the coefficients from J/A+A/556/A86/table16 and J/A+A/554/A98/table16 when possible (compatible spectral types) and following the prescriptions of the JMMC report JMMC-MEM-2610-001 ( in all other cases. As the limb-darkening coefficients depend on the effective temperature and surface gravity as well as some model of the stellar photosphere, these "revised" LDDs are not part of the present catalog. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file jmdc.dat 422 1478 JMMC Measured stellar Diameters Catalog (as part of Chelli et al., 2016A&A...589A.112C) jmdc.fits 2880 200 FITS version of the catalog
See also: II/224 : Catalog of Stellar Diameters (CADARS) (Pasinetti-Fracassini+ 2001) J/A+A/431/773 : CHARM2, an updated of CHARM catalog (Richichi+, 2005) J/A+A/556/A86 : FGK dwarf stars limb darkening coefficients (Neilson+, 2013) Byte-by-byte Description of file: jmdc.dat
Bytes Format Units Label Explanations
1- 23 A23 --- ID1 Normalised star name (preferably HD) (ID1) 25- 44 A20 --- ID2 Name used in the original publication (ID2) 47- 59 E13.6 mas UDdiam ?=-1 Uniform Disk Diameter (UD_MEAS) 61- 73 E13.6 mas LDdiam ?=-1 Limb-Darkened Disk diameter (LD_MEAS) 75- 87 E13.6 mas e_LDdiam ?=-1 Error on UDdiam and LDdiam (ELDMEAS) (1) 88- 97 A10 --- Band Text describing the wavelength or band of the measurement (BAND) (2) 99-111 E13.6 --- mu-lambda ?=- When possible, value of the conversion UDD-to-LDD user by the author (ORIGMULAMBDA) 113 I1 --- Method Integer code of the method used (METHOD) (3) 115-117 I3 --- BandCode ?=- Integer code of the band used (BANDCODE) (4) 119-342 A224 --- Notes Note about the star and/or measurement (NOTES) 344-362 A19 --- BibCode BibCode 364-422 A59 --- Com Author's name and comments (REFERENCE)
Note (1): In general, quotes the published error on LDD or UDD, which are essentially equivalent. The blanking value of -1 can be due to an absence of published error, or has been fixed thus when the measurement is (retrospectively) in doubt, in which case an explanation lies in the Notes. Note (2): A loosely defined string representing the band (UBVRIJHKLMNQ) or the central wavelength, in microns if not otherwise precised, of the observation. A stands for Angstroem, nm for nanometer. Note (3): Code for the observational method used as follows: 1 = optical interferometry 2 = Lunar occultation 3 = intensity interferometry Note (4): Index from 1 (band U) and up through bands B,V,R,I,J,H,K,L,M,N,Q.
History: * 28-Nov-2016: First version with 1239 measurements * 29-Mar-2018: New version with 1478 measurements Acknowledgements: Gilles Duvert, gilles.duvert(at)
(End) Gilles Duvert [IPAG, OSUG, France], Patricia Vannier [CDS] 17-Nov-2016
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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