J/A+A/697/A8 NGC 6254 (M10) and NGC 6397 Euclid photometry (Massari+, 2025)
Euclid: Early Release Observations - Unveiling the morphology of two Milky Way
globular clusters out to their periphery.
Massari D., Dalessandro E., Erkal D., Balbinot E., Bovy J., McDonald I.,
Ferguson A.M.N., Larsen S., Lancon A., Annibali F., Goldman B., Kuzma P.B.,
Voggel K., Saifollahi T., Cuillandre J.-C., Schirmer M., Kluge M.,
Altieri B., Amara A., Andreon S., Auricchio N., Baldi M., Balestra A.,
Bardelli S., Basset A., Bender R., Bonino D., Branchini E., Brescia M.,
Brinchmann J., Camera S., Candini G.P., Capobianco V., Carbone C.,
Carretero J., Casas S., Castellano M., Cavuoti S., Cimatti A., Congedo G.,
Conselice C.J., Conversi L., Copin Y., Corcione L., Courbin F.,
Courtois H.M., Degaudenzi H., Dinis J., Dubath F., Dupac X., Dusini S.,
Fabricius M., Farina M., Farrens S., Ferriol S., Frailis M., Franceschi E.,
Garilli B., Gillis B., Giocoli C., Grazian A., Guzzo L., Hoar J.,
Hoekstra H., Holliman M.S., Holmes W., Hook I., Hormuth F., Hornstrup A.,
Hudelot P., Jahnke K., Keihanen E., Kermiche S., Kiessling A., Kitching T.,
Kohley R., Kubik B., Kummel M., Kunz M., Kurki-Suonio H., Ligori S.,
Lilje P.B., Lindholm V., Lloro I., Maino D., Maiorano E., Mansutti O.,
Marggraf O., Markovic K., Martinet N., Marulli F., Massey R.,
Maurogordato S., Medinaceli E., Mei S., Mellier Y., Meneghetti M.,
Meylan G., Moresco M., Moscardini L., Munari E., Nakajima R., Nichol R.C.,
Niemi S.-M., Padilla C., Paltani S., Pasian F., Pedersen K., Percival W.J.,
Pettorino V., Pires S., Polenta G., Poncet M., Popa L.A., Pozzetti L.,
Racca G.D., Raison F., Rebolo R., Renzi A., Rhodes J., Riccio G.,
Rix H.-W. , Romelli E., Roncarelli M., Rossetti E., Saglia R.,
Sapone D., Sartoris B., Schneider P., Schrabback T., Secroun A., Seidel G.,
Seiffert M., Serrano S., Sirignano C., Sirri G., Skottfelt J., Stanco L.,
Teplitz H.I., Tereno I., Toledo-Moreo R., Torradeflot F., Tutusaus I.,
Valenziano L., Vassallo T., Veropalumbo A., Wang Y., Weller J., Zacchei A.,
Zamorani G., Zoubian J., Zucca E., Bolzonella M., Burigana C., Morris P.W.,
Scottez V.
<Astron. Astrophys. 697, A8 (2025)>
=2025A&A...697A...8M 2025A&A...697A...8M (SIMBAD/NED BibCode)
ADC_Keywords: Milky Way ; Clusters, globular ; Photometry, infrared ; Optical
Keywords: stars: imaging - Galaxy: evolution - globular clusters: general -
Galaxy: structure - globular clusters: individual: NGC 6254 -
globular clusters: individual: NGC 6397
Abstract:
As part of the Euclid Early Release Observations (ERO) programme, we
analysed deep, wide-field imaging from the VIS and NISP instruments of
two Milky Way globular clusters (GCs), namely NGC 6254 (M10) and
NGC 6397, to look for observational evidence of their dynamical
interaction with the Milky Way. We searched for such an interaction in
the form of structural and morphological features in the clusters'
outermost regions, which would be suggestive of the development of
tidal tails on scales larger than those sampled by the ERO data. From
our multi-band photometric analysis, we obtained deep and well-behaved
colour--magnitude diagrams that, in turn, enabled an accurate
membership selection. The surface brightness profiles built from these
samples of member stars are the deepest ever obtained for these two
Milky Way GCs, reaching down to 30.0mag/arcsec2, which is
∼1.5mag/arcsec2 lower than before. The investigation of the
two-dimensional density map of NGC 6254 reveals an elongated
morphology of the cluster peripheries in the direction and with the
amplitude predicted by N-body simulations of the cluster's dynamical
evolution, at high statistical significance. We interpret this as
strong evidence for the first detection of tidally induced
morphological distortion around this cluster. The density map of NGC
6397 reveals a slightly elliptical morphology, in agreement with
previous studies, which requires further investigation on larger
scales to be properly interpreted. This ERO project thus demonstrates
the power of Euclid in studying the outer regions of GCs at an
unprecedented level of detail, thanks to the combination of the large
field of view, high spatial resolution, and depth enabled by the
telescope. Our results highlight the future Euclid survey as the ideal
dataset for investigating GC tidal tails and stellar streams.
Description:
m10.dat: Astrometry and differential reddening corrected photometry of
sources around M10. The sources have been selected in order to exclude
likely artifacts and extended ones, see the description in the paper
ngc6397.dat: Astrometry and differential reddening corrected
photometry of sources around NGC6397. The sources have been selected
in order to exclude likely artifacts and extended ones, see the
description in the paper
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
m10.dat 37 85675 Astro-photometry for stars around M10 (NGC6254)
ngc6397.dat 37 220928 Astro-photometry for stars around NGC6397
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Byte-by-byte Description of file: m10.dat ngc6397.dat
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Bytes Format Units Label Explanations
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1- 11 F11.7 deg RAdeg Right Ascension (J2000)
13- 23 F11.7 deg DEdeg Declination (J2000)
25- 30 F6.3 mag IEmag Photometry in the Euclid IE (550-900nm) band
32- 37 F6.3 mag HEmag Photometry in the Euclid HE (17825.15Å) band
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Acknowledgements:
Davide Massari, davide.massari(at)inaf.it
(End) Patricia Vannier [CDS] 08-Aug-2024