J/A+A/712/A174 Euclid. Convective-transition gap of 47 Tuc (Libralato+, 2026)
Euclid: The convective-transition gap of 47 Tuc.
Libralato M., Griggio M., Gerasimov R., Bedin L.R., McDonald I., Altieri B.,
Anderson J., Annibali F., Balbinot E., Battaglia G., Bellini A.,
Casenove P., Cuillandre J.-C., Dalessandro E., Ferguson A.M.N.,
Jones H.R.A., Kuijken K., Majidi F.Z., Massari D., Mohandasan A.,
Niederhofer F., Polenta G., Sakowska J.D., Soldano F., Zerbinati C.,
Andreon S., Auricchio N., Aussel H., Baccigalupi C., Baldi M., Balestra A.,
Battaglia P., Biviano A., Branchini E., Brescia M., Camera S.,
Capobianco V., Carbone C., Carretero J., Castellano M., Castignani G.,
Cavuoti S., Chambers K.C., Cimatti A., Colodro-Conde C., Congedo G.,
Conselice C.J., Conversi L., Copin Y., Courbin F., Courtois H.M.,
Cropper M., Degaudenzi H., De Lucia G., Dole H., Dubath F., Dupac X.,
Farina M., Farinelli R., Faustini F., Ferriol S., Frailis M., Franceschi E.,
Galeotta S., George K., Gillis B., Giocoli C., Gracia-Carpio J., Grazian A.,
Grupp F., Haugan S.V.H., Hoekstra H., Holmes W., Hook I.M., Hormuth F.,
Hornstrup A., Jahnke K., Jhabvala M., Kermiche S., Kiessling A., Kubik B.,
Kummel M., Kunz M., Kurki-Suonio H., Le Brun A.M.C., Ligori S., Lilje P.B.,
Lindholm V., Lloro I., Mansutti O., Marggraf O., Martinelli M., Martinet N.,
Marulli F., Massey R.J., Medinaceli E., Mei S., Meneghetti M., Merlin E.,
Meylan G., Mora A., Moscardini L., Nakajima R., Nichol R.C., Niemi S.-M.,
Padilla C., Paltani S., Pasian F., Percival W.J., Pettorino V., Poncet M.,
Popa L.A., Raison F., Renzi A., Rhodes J., Riccio G., Rizzo F., Romelli E.,
Roncarelli M., Saglia R., Sakr Z., Sapone D., Schirmer M., Schneider P.,
Schrabback T., Secroun A., Sihvola E., Simon P., Sirignano C., Sirri G.,
Stanco L., Tallada-Cresp'i P., Taylor A.N., Tereno I., Toft S.,
Toledo-Moreo R., Torradeflot F., Tutusaus I., Valiviita J., Vassallo T.,
Wang Y., Weller J., Scott D.
<Astron. Astrophys. 712, A174 (2026)>
=2026A&A...712A.174L 2026A&A...712A.174L (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, globular ; Photometry, infrared ; Optical ;
Morphology
Keywords: techniques: photometric - stars: low-mass -
stars: luminosity function, mass function -
globular clusters: individual: NGC 104
Abstract:
We report the first detection of the `convective-transition gap' (also
known as the `M-dwarf gap') in the globular cluster 47 Tuc (NGC 104).
This feature, linked to a change in the physical properties of
late-type dwarfs, has remained elusive, with only two detections so
far. Leveraging the large number of stars, high resolution, and
photometric precision enabled by Euclid, we detected a statistically
significant, sharp discontinuity in the main-sequence luminosity
function of 47 Tuc at IE∼22.9, which we identify as the
convective-transition gap. A comparison of the observed properties of
the gap in 47 Tuc with theoretical models shows how the gap can be a
powerful diagnostic for probing the internal chemical structure of
globular clusters and their multiple stellar populations. Following
its initial discovery in the metal-poor cluster NGC 6397, the
identification of a convective gap in the metal-rich 47 Tuc suggests
that this feature is more general than previously thought. These
results demonstrate that Euclid can be transformative well beyond
cosmology, with impacts across multiple areas of astrophysics,
including resolved stellar populations.
Description:
Official Euclid Level 2 individual frames and stacked catalogs.
See official documentation of Sextractor for a complete description of
the Sextractor-related columns.
See official documentation of the Euclid products for a complete
description of all columns.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
nir-h1.dat 724 162234 Euclid H catalog, 2025-12-16T15:12:57.874665
nir-j1.dat 724 177870 Euclid J catalog, 2025-12-16T15:14:06.945811
nir-y1.dat 724 198959 Euclid Y catalog, 2025-12-16T15:18:13.783896
nir-h2.dat 724 170683 Euclid H catalog, 2025-12-16T15:08:33.359407
nir-j2.dat 724 160821 Euclid J catalog, 2025-12-16T15:09:27.803120
nir-y2.dat 724 137595 Euclid Y catalog, 2025-12-16T15:05:46.768079
nir-h3.dat 724 184552 Euclid H catalog, 2025-12-16T15:08:13.685295
nir-j3.dat 724 189959 Euclid J catalog, 2025-12-16T15:01:49.894994
nir-y3.dat 724 181202 Euclid Y catalog, 2025-12-16T14:58:52.077081
nir-h4.dat 724 174157 Euclid H catalog, 2025-12-16T15:08:31.347452
nir-j4.dat 724 155853 Euclid J catalog, 2025-12-16T15:10:42.080801
nir-y4.dat 724 176568 Euclid Y catalog, 2025-12-16T15:09:12.834135
vis1.dat 3047 858547 Euclid VIS catalog, 2025-12-17T08:44:14.590165
vis2.dat 3047 1560371 Euclid VIS catalog, 2025-12-17T14:37:17.046226
vis3.dat 3047 1405931 Euclid VIS catalog, 2025-12-17T11:01:12.319507
vis4.dat 3047 857030 Euclid VIS catalog, 2025-12-17T07:19:16.558249
list.dat 124 68 List of fits images
images/* . 68 Individual fits images
catalogs/* . 16 Individual fits catalogs
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See also:
J/A+A/692/A96 : NGC 6397 Euclid/Gaia internal kinematics (Libralato+, 2024)
Byte-by-byte Description of file: nir*.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 I6 --- ObjectID Unique source identifier (MER tool)
8- 27 F20.15 pix XwinImg Windowed position estimate along x axis
(XWIN_IMAGE)
29- 49 F21.15 pix YwinImg Windowed position estimate along y axis
(YWIN_IMAGE)
51- 68 F18.16 deg XwinW Windowed position along world x axis
(XWIN_WORLD)
70- 87 F18.14 deg YwinW Windowed position along world y axis
(YWIN_WORLD)
89-106 F18.16 deg RAdeg Right ascension of barycenter (J2000),
Sextractor (ALPHA_J2000)
108-125 F18.14 deg DEdeg Declination of barycenter (J2000),
Sextractor (DELTA_J2000)
127-133 F7.4 mag mag1 Fixed aperture 1 magnitude vector,
Sextractor (MAG_APER1)
135-141 F7.4 mag mag2 Fixed aperture 2 magnitude vector,
Sextractor (MAG_APER2)
143-149 F7.4 mag mag3 Fixed aperture 3 magnitude vector,
Sextractor (MAG_APER3)
151-157 F7.4 mag mag4 Fixed aperture 4 magnitude vector,
Sextractor (MAG_APER4)
159-165 F7.4 mag mag5 Fixed aperture 5 magnitude vector,
Sextractor (MAG_APER5)
167-178 E12.6 mag e_mag1 rms error vector for fixed aperture 1
magnitude, Sextractor (MAGERR_APER1)
180-191 E12.6 mag e_mag2 rms error vector for fixed aperture 2
magnitude, Sextractor (MAGERR_APER2)
193-204 E12.6 mag e_mag3 rms error vector for fixed aperture 3
magnitude, Sextractor (MAGERR_APER3)
206-217 E12.6 mag e_mag4 rms error vector for fixed aperture 4
magnitude, Sextractor (MAGERR_APER4)
219-230 E12.6 mag e_mag5 rms error vector for fixed aperture 5
magnitude, Sextractor (MAGERR_APER5)
232-243 E12.6 ct Flux1 Flux vector within fixed circular
aperture 1, Sextractor (FLUX_APER1)
245-256 E12.6 ct Flux2 Flux vector within fixed circular
aperture 2, Sextractor (FLUX_APER2)
258-269 E12.6 ct Flux3 Flux vector within fixed circular
aperture 3, Sextractor (FLUX_APER3)
271-282 E12.6 ct Flux4 Flux vector within fixed circular
aperture 4, Sextractor (FLUX_APER4)
284-295 E12.6 ct Flux5 Flux vector within fixed circular
aperture 5, Sextractor (FLUX_APER5)
297-304 F8.6 ct e_Flux1 rms error vector for aperture 1 flux,
Sextractor (FLUXERR_APER1)
306-313 F8.6 ct e_Flux2 rms error vector for aperture 2 flux,
Sextractor (FLUXERR_APER2)
315-322 F8.6 ct e_Flux3 rms error vector for aperture 3 flux,
Sextractor (FLUXERR_APER3)
324-331 F8.6 ct e_Flux4 rms error vector for aperture 4 flux,
Sextractor (FLUXERR_APER4)
333-340 F8.6 ct e_Flux5 rms error vector for aperture 5 flux,
Sextractor (FLUXERR_APER5)
342-348 F7.4 mag magAuto Kron-like elliptical aperture magnitude,
Sextractor (MAG_AUTO)
350-357 F8.6 mag e_magAuto rms error for AUTO magnitude,
Sextractor (MAGERR_AUTO)
359-370 E12.6 ct FluxAuto Flux within a Kron-like elliptical aperture,
Sextractor (FLUX_AUTO)
372-379 F8.6 ct e_FluxAuto rms error for AUTO flux,
Sextractor (FLUXERR_AUTO)
381-392 E12.6 deg awinW Windowed profile rms along major axis,
Sextractor (AWIN_WORLD)
394-405 E12.6 deg bwinW ?=- Windowed profile rms along minor axis,
Sextractor (BWIN_WORLD)
407-416 F10.6 deg thetawinW Windowed position angle (CCW/world-x),
Sextractor (THETAWIN_WORLD)
418-429 E12.6 deg e_awinW World rms windowed pos error along major
axis, Sextractor (ERRAWIN_WORLD)
431-442 E12.6 deg e_bwinW World rms windowed pos error along minor
axis, Sextractor (ERRBWIN_WORLD)
444-453 F10.6 deg e_thetawinW [] Windowed error ellipse pos. angle
(CCW/world-x), Sextractor
(ERRTHETAWIN_WORLD)
455-461 F7.5 --- KronRad Kron apertures in units of A or B,
Sextractor (KRON_RADIUS)
463-470 F8.6 --- Ell Source ELLIPTICITY shape parameter,
1-bIMAGE/aIMAGE, Sextractor (ELLIPTICITY)
472-479 F8.6 --- ClassStar Source star class shape parameter. S/G
classifier output, Sextractor (CLASS_STAR)
481-489 F9.6 pix FWHMImg FWHM assuming a gaussian core,
Sextractor (FWHM_IMAGE)
491-499 F9.6 pix FluxRad Fraction-of-light radii,
Sextractor (FLUX_RADIUS)
501-510 F10.6 ct Bkg Background at centroid position,
Sextractor (BACKGROUND)
512-519 F8.6 ct Threshold Detection threshold about background,
Sextractor (THRESHOLD)
521-540 F20.15 pix XPSFImg X coordinate from PSF-fitting (XPSF_IMAGE)
542-562 F21.15 pix YPSFImg Y coordinate from PSF-fitting (YPSF_IMAGE)
564-581 F18.16 deg XPSFW PSF position along world x axis (XPSF_WORLD)
583-600 F18.14 deg YPSFW PSF position along world y axis (YPSF_WORLD)
602-619 F18.16 deg RAPdeg Right ascension of the fitted PSF (J2000),
Sextractor (ALPHAPSF_J2000)
621-638 F18.14 deg DEPdeg Declination of the fitted PSF (J2000),
Sextractor (ALPHAPSF_J2000)
640-646 F7.4 mag magPSF Magnitude from PSF-fitting,
Sextractor (MAG_PSF)
648-656 F9.6 mag e_magPSF rms magnitude error from PSF-fitting,
Sextractor (MAGERR_PSF)
658-669 E12.6 ct FluxPSF Flux from PSF-fitting, Sextractor (FLUX_PSF)
671-679 F9.6 ct e_FluxPSF rms flux error for PSF-fitting,
Sextractor (FLUXERR_PSF)
681-689 F9.6 pix e_aPSFImg PSF rms position error along major axis,
Sextractor (ERRAPSF_IMAGE)
691-698 F8.6 pix e_bPSFImg PSF rms position error along minor axis,
Sextractor (ERRBPSF_IMAGE)
700-709 F10.6 deg e_thetaPSFImg [] PSF error ellipse position angle (CCW/x),
Sextractor (ERRTHETAPSF_IMAGE)
711-722 E12.6 --- Chi2PSF ?=- Reduced chi2 from PSF-fitting,
Sextractor (CHI2_PSF)
724 I1 --- Flags SExtractor Extraction flags,
Sextractor (FLAGS)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: vis1.dat vis2.dat vis3.dat vis4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 I10 --- Number Running object number (NUMBER)
12- 24 F13.7 pix XImg Object position along x (X_IMAGE)
26- 38 F13.7 pix YImg Object position along y (Y_IMAGE)
40- 60 F21.15 pix XPSFImg X coordinate from PSF-fitting
(XPSF_IMAGE)
62- 83 F22.16 pix YPSFImg Y coordinate from PSF-fitting
(YPSF_IMAGE)
85- 102 F18.16 deg XW Barycenter position along world x
axis (X_WORLD)
104- 121 F18.14 deg YW Barycenter position along world y
axis (Y_WORLD)
123- 134 E12.6 deg e_aW Major axis of the isophotal image
centroid error ellipse (ERRA_WORLD)
136- 147 E12.6 deg e_bW ?=- Minor axis of the isophotal
image centroid error ellipse
(ERRB_WORLD)
149- 158 F10.6 deg e_thetaW [] Position angle of the isophotal
image centroid ellipse
(ERRTHETA_WORLD)
160- 177 F18.16 deg XPSFW PSF position along world x axis
(XPSF_WORLD)
179- 196 F18.14 deg YPSFW PSF position along world y axis
(YPSF_WORLD)
198- 209 E12.6 pix e_aPSFW Major axis of the PSF
(ERRAPSF_WORLD)
211- 222 E12.6 pix e_bPSFW Minor axis of the PSF
(ERRBPSF_WORLD)
224- 233 F10.6 deg e_thetaPSFW [] Position angle of the PSF
(ERRTHETAPSF_WORLD)
235- 246 E12.6 deg aW Profile rms along major axis
(world units) (A_WORLD)
248- 259 E12.6 deg bW ?=- Profile rms along minor axis
(world units) (B_WORLD)
261- 270 F10.6 deg thetaW Position angle (CCW/world-x)
(THETA_WORLD)
272- 293 E22.17 deg2 e_X2W Estimated variance of isophotal
image centroid x coordinate
(ERRX2_WORLD)
295- 316 E22.17 deg2 e_Y2W Estimated variance of isophotal
image centroid y coordinate
(ERRY2_WORLD)
318- 335 F18.16 deg RAdeg Right ascension (J2000) of the
isophotal image centroid
(ALPHA_J2000)
337- 354 F18.14 deg DEdeg Declination (J2000) of the
isophotal image centroid
(DELTA_J2000)
356- 365 F10.6 deg e_theta [] Position angle (J2000) of the
isophotal image centroid ellipse
(ERRTHETA_J2000)
367- 376 F10.6 deg theta Isophotal image position angle
(THETA_J2000)
378- 395 F18.16 deg XwinW x coordinate of windowed image
centroid (XWIN_WORLD)
397- 414 F18.14 deg YwinW y coordinate of windowed image
centroid (YWIN_WORLD)
416- 433 F18.16 deg RAPdeg Right ascension of the fitted PSF
(J2000) (ALPHAPSF_J2000)
435- 452 F18.14 deg DEPdeg Declination of the fitted PSF
(J2000) (DELTAPSF_J2000)
454- 463 F10.6 deg e_thetaP [] Position angle of the fitted PSF
(J2000) (ERRTHETAPSF_J2000)
465- 482 F18.16 deg RAWdeg Right ascension of the windowed
image (ALPHAWIN_J2000)
484- 501 F18.14 deg DEWdeg Declination of of the windowed
image (DELTAWIN_J2000)
503- 514 E12.6 deg e_awinW Major axis of the windowed image
centroid error ellipse
(ERRAWIN_WORLD)
516- 527 E12.6 deg e_bwinW ?=- Minor axis of the windowed
image centroid error ellipse
(ERRBWIN_WORLD)
529- 538 F10.6 deg e_thetawinW [] Position angle of the windowed
image centroid ellipse
(ERRTHETAWIN_WORLD)
540- 551 E12.6 deg awinW Windowed image major axis
(AWIN_WORLD)
553- 564 E12.6 deg bwinW ?=- Windowed image minor axis
(BWIN_WORLD)
566- 575 F10.6 deg thetawinW Windowed image position angle
(THETAWIN_WORLD)
577- 586 F10.6 deg2 e_X2winW Estimated variance of windowed image
centroid x coordinate
(ERRX2WIN_WORLD)
588- 597 F10.6 deg2 e_Y2winW Estimated variance of windowed image
centroid y coordinate
(ERRY2WIN_WORLD)
599- 606 F8.4 mag/arcsec2 muThreshold The surface brightness corresponding
to the threshold (MU_THRESHOLD)
608- 615 F8.4 mag/arcsec2 mumax The surface brightness of the
brightest pixel (MU_MAX)
617- 624 F8.4 mag/arcsec2 mumaxMod Peak model surface brightness above
the background (MUMAXMODEL)
626- 633 F8.4 mag/arcsec2 mueffMod Effective model surface brightness
above the background (MUEFFMODEL)
635- 642 F8.4 mag/arcsec2 mumeanMod Mean effective model surface
brightness above the background
(MUMEANMODEL)
644- 651 F8.4 mag/arcsec2 mumaxSphe Peak model surface brightness above
the background using Sersic
spheroid model (MUMAXSPHEROID)
653- 660 F8.4 mag/arcsec2 mueffSphe Effective model surface brightness
above the background using Sersic
spheroid model (MUEFFSPHEROID)
662- 669 F8.4 mag/arcsec2 mumeanSphe Mean effective model surface
brightness above the background
using Sersic spheroid model
(MUMEANSPHEROID)
671- 678 F8.4 mag/arcsec2 mumaxDisk Peak model surface brightness above
the background using exponential
disk model (MUMAXDISK)
680- 689 F10.6 mag/arcsec2 mueffDisk Effective model surface brightness
above the background using
exponential disk model
(MUEFFDISK)
691- 700 F10.6 mag/arcsec2 mumeanDisk Mean effective model surface
brightness above the background
using exponential disk model
(MUMEANDISK)
702- 709 F8.3 --- Ell 1-bIMAGE/aIMAGE (ELLIPTICITY)
711- 728 F18.10 ct FluxAuto Flux within a Kron-like elliptical
aperture (This flux is not
calibrated) (FLUX_AUTO)
730- 743 F14.10 ct e_FluxAuto Flux in an aperture (This flux is
not calibrated) (FLUXERR_AUTO)
745- 754 F10.7 mag magAuto Kron-like elliptical aperture
magnitude (This magnitude is
calibrated) (MAG_AUTO)
756- 769 F14.11 mag e_magAuto rms .error for AUTO magnitude
(MAGERR_AUTO)
771- 780 F10.7 ct Bkg Background at centroid position
(BACKGROUND)
782- 791 E10.7 mag mag1 Magnitude calibrated in a defined
aperture 1 (MAG_APER1)
793- 802 E10.7 mag mag2 Magnitude calibrated in a defined
aperture 2 (MAG_APER2)
804- 813 E10.7 mag mag3 Magnitude calibrated in a defined
aperture 3 (MAG_APER3)
815- 824 E10.7 mag mag4 Magnitude calibrated in a defined
aperture 4 (MAG_APER4)
826- 837 E12.6 mag e_mag1 Error of the calibrated magnitude
in aperture 1 (MAGERR_APER1)
839- 850 E12.6 mag e_mag2 Error of the calibrated magnitude
in aperture 2 (MAGERR_APER2)
852- 863 E12.6 mag e_mag3 Error of the calibrated magnitude
in aperture 3 (MAGERR_APER3)
865- 876 E12.6 mag e_mag4 Error of the calibrated magnitude
in aperture 4 (MAGERR_APER4)
878- 889 E12.6 ct Flux1 Flux in an aperture 1 (This flux is
not calibrated (FLUX_APER1)
891- 902 E12.6 ct Flux2 Flux in an aperture 2 (This flux is
not calibrated (FLUX_APER2)
904- 915 E12.6 ct Flux3 Flux in an aperture 3 (This flux is
not calibrated (FLUX_APER3)
917- 928 E12.6 ct Flux4 Flux in an aperture 4 (This flux is
not calibrated (FLUX_APER4)
930- 941 E12.6 ct e_Flux1 rms error of flux aperture 1
(FLUXERR_APER1)
943- 954 E12.6 ct e_Flux2 rms error of flux aperture 2
(FLUXERR_APER2 )
956- 967 E12.6 ct e_Flux3 rms error of flux aperture 3
(FLUXERR_APER3)
969- 980 E12.6 ct e_Flux4 rms error of flux aperture 4
(FLUXERR_APER4)
982- 991 F10.6 mag magPSF Magnitude from PSF-fitting (MAG_PSF)
993-1004 E12.6 mag e_magPSF rms magnitude error from PSF-fitting
(MAGERR_PSF)
1006-1019 F14.8 pix FluxRad Fraction-of-light radii (pixels)
(FLUX_RADIUS)
1021-1031 F11.7 --- Elong A IMAGE/B IMAGE (ELONGATION)
1033-1049 F17.11 pix FWHMImg FWHM assuming a Gaussian core
(FWHM_IMAGE)
1051-1062 E12.6 --- SNRwin Signal to noise ratio of the
windowed image (SNR_WIN)
1064-1075 E12.6 --- SpreadMod Spread parameter from model-fitting,
stars are object with:
abs(SPREAD_MODEL)<0.003
(SPREAD_MODEL)
1077-1079 I3 --- Flags SExtractor extraction flags, basic
warnings about the source
extraction process, in order of
increasing concern (FLAGS)
1081-1082 I2 --- Flagswin SExtractor flag for various issues
which may happen with windowed
measurements (FLAGS_WIN)
1084-1085 I2 --- FlagsMod SExtractor flag for various issues
which may happen during the fitting
process (FLAGS_MODEL)
1087-1100 F14.11 pix e_awinImg Major axis of the windowed image
centroid error ellipse
(ERRAWIN_IMAGE)
1102-1114 F13.11 pix e_bwinImg Minor axis of the windowed image
centroid error ellipse
(ERRBWIN_IMAGE)
1116-1127 E12.6 deg e_thetawinImg [] Position angle of the windowed
image centroid ellipse
(ERRTHETAWIN_IMAGE)
1128-1257 10E13.6 --- VectorMod Multi-column model-fitting
coefficients (VECTOR_MODEL)
1258-1387 10E13.6 --- e_VectorMod Multi-column model-fitting
coefficient uncertainties
(VECTOR_MODELERR)
1388-2687 100E13.6 --- MatrixModErr Multi-column model-fitting
covariance matrix (MATRIX_MODELERR)
2689-2701 F13.9 --- Chi2Mod Reduced Chi2 of the fit (CHI2_MODEL)
2703-2705 I3 --- NiterMod Number of iterations for
model-fitting (NITER_MODEL)
2707-2718 E12.6 ct FluxMod Flux from model-fitting (FLUX_MODEL)
2720-2731 E12.6 ct e_FluxMod rms .error on model-fitting flux
(FLUXERR_MODEL)
2733-2742 F10.7 mag magMod Magnitude from model-fitting
(MAG_MODEL)
2744-2755 E12.6 mag e_magMod rms.error on model-fitting magnitude
(MAGERR_MODEL)
2757-2777 F21.15 pix XModImg X coordinate from model-fitting
(XMODEL_IMAGE)
2779-2801 F23.16 pix YModImg Y coordinate from model-fitting
(YMODEL_IMAGE)
2803-2820 F18.16 deg XModW Fitted position along world x axis
(XMODEL_WORLD)
2822-2839 F18.14 deg YModW Fitted position along world y axis
(YMODEL_WORLD)
2841-2852 E12.6 --- Ell1ModImg Ellipticity component from
model-fitting (ELLIP1MODEL_IMAGE)
2854-2865 E12.6 --- Ell2ModImg Ellipticity component from
model-fitting (ELLIP2MODEL_IMAGE)
2867-2878 E12.6 --- e_Ell1ModImg Ellipticity component std.error from
model-fitting
(ELLIP1ERRMODEL_IMAGE)
2880-2891 E12.6 --- e_Ell2ModImg Ellipticity component std.error from
model-fitting
(ELLIP2ERRMODEL_IMAGE)
2893-2904 E12.6 --- EllModImgCor Correction coefficient between
ellip.components from model-fitting
(ELLIPCORRMODEL_IMAGE)
2906-2917 E12.6 --- Ell1MolW Ellipticity component from
model-fitting (ELLIP1MODEL_WORLD)
2919-2930 E12.6 --- Ell2MolW Ellipticity component from
model-fitting (ELLIP2MODEL_WORLD)
2932-2943 E12.6 --- e_Ell1ModW Ellipticity component std.error from
model-fitting
(ELLIP1ERRMODEL_WORLD)
2945-2956 E12.6 --- e_Ell2ModlW Ellipticity component std.error from
model-fitting
(ELLIP2ERRMODEL_WORLD)
2958-2969 E12.6 --- e_EllModWCor [] Correction coefficient between
ellip.components from model-fitting
(ELLIPCORRMODEL_WORLD)
2971-2991 F21.15 pix XwinImg x coordinate of windowed image
centroid (XWIN_IMAGE)
2993-3014 F22.16 pix YWinImg y coordinate of windowed image
centroid (YWIN_IMAGE)
3016-3034 I19 --- GaiaDR3 ?=- Gaia ID (GAIA_ID)
3036-3047 E12.6 --- SNR ?=- Signal to noise ratio define as
FLUXAPER/FLUXERRAPER in the
50 pixel aperture (SNR)
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 F9.5 deg RAdeg Right Ascension of center (J2000)
10- 18 F9.5 deg DEdeg Declination of center (J2000)
20- 24 F5.3 arcsec/pix scale Scale of the image
26- 29 I4 --- Nx Number of pixels along X-axis
31- 34 I4 --- Ny Number of pixels along Y-axis
36- 61 A26 "datime" Obs.date Observation date
63- 66 I4 Mbyte size Size of FITS file
68-124 A57 --- FileName Name of FITS file, in subdirectory images
--------------------------------------------------------------------------------
Acknowledgements:
Mattia Libralato, mattia.libralato(at)inaf.it
License: CC-BY-4.0
(End) Patricia Vannier [CDS] 2-Jul-2026