J/A+A/692/A96 NGC 6397 Euclid/Gaia internal kinematics (Libralato+, 2024)
Euclid: High-precision imaging astrometry and photometry from Early Release
Observations.
I. Internal kinematics of NGC 6397 by combining Euclid and Gaia data.
Libralato M., Bedin L.R., Griggio M., Massari D., Anderson J.,
Cuillandre J.-C., Ferguson A.M.N., Lancon A., Larsen S.S., Schirmer M.,
Annibali F., Balbinot E., Dalessandro E., Erkal D., Kuzma P.B.,
Saifollahi T., Verdoes Kleijn G., Kuemmel M., Nakajima R., Correnti M.,
Battaglia G., Altieri B., Amara A., Andreon S., Baccigalupi C., Baldi M.,
Balestra A., Bardelli S., Basset A., Battaglia P., Bonino D., Branchini E.,
Brescia M., Brinchmann J., Caillat A., Camera S., Capobianco V., Carbone C.,
Carretero J., Casas S., Castellano M., Castignani G., Cavuoti S.,
Cimatti A., Colodro-Conde C., Congedo G., Conselice C.J., Conversi L.,
Copin Y., Courbin F., Courtois H.M., Cropper M., Da Silva A., Degaudenzi H.,
De Lucia G., Dinis J., Dubath F., Dupac X., Dusini S., Fabricius M.,
Farina M., Farrens S., Faustini F., Ferriol S., Fosalba P., Frailis M.,
Franceschi E., Fumana M., Galeotta S., Garilli B., George K., Gillard W.,
Gillis B., Giocoli C., Gomez-Alvarez P., Grazian A., Grupp F., Guzzo L.,
Haugan S.V.H., Hoar J., Hoekstra H., Holmes W., Hormuth F., Construes A.,
Hudelot P., Jahnke K., Jhabvala M., Keihaenen E., Kermiche S., Kiessling A.,
Kilbinger M., Kubik B., Kunz M., Kurki-Suonio H., Laureijs R.,
Le Mignant D., Ligori S., Lilje P.B., Lindholm V., Lloro I., Maiorano E.,
Mansutti O., Marggraf O., Markovic K., Martinelli M., Martinet N.,
Marulli F., Massey R., Medinaceli E., Mei S., Melchior M., Mellier Y.,
Meneghetti M., Merlin E., Meylan G., Moresco M., Moscardini L., Neissner C.,
Nichol R.C., Niemi S.-M., Nightingale J.W., Padilla C., Paltani S.,
Pasian F., Pedersen K., Percival W.J., Pettorino V., Pires S., Polenta G.,
Poncet M., Popa L.A., Pozzetti L., Raison F., Rebolo R., Refregier A.,
Renzi A., Rhodes J., Riccio G., Romelli E., Roncarelli M., Rossetti E.,
Saglia R., Sakr Z., Sanchez A.G., Sapone D., Sartoris B., Sauvage M.,
Schneider P., Schrabback T., Secroun A., Sefusatti E., Seidel G.,
Seiffert M., Serrano S., Sirignano C., Sirri G., Skottfelt J., Stanco L.,
Steinwagner J., Tallada-Crespi P., Taylor A.N., Teplitz H.I., Tereno I.,
Toledo-Moreo R., Torradeflot F., Tsyganov A., Tutusaus I., Valenziano L.,
Vassallo T., Veropalumbo A., Wang Y., Weller J., Zamorani G., Zucca E.,
Burigana C., Scottez V., Scott D., Smart R.L.,
<Astron. Astrophys. 692, A96 (2024)>
=2024A&A...692A..96L 2024A&A...692A..96L (SIMBAD/NED BibCode)
ADC_Keywords: Surveys ; Clusters, globular ; Photometry, infrared ; Optical ;
Proper motions
Keywords: techniques: photometric - astrometry - proper motions -
globular clusters: individual: NGC 6397
Abstract:
The instruments at the focus of the Euclid space observatory offer
superb, diffraction-limited imaging over an unprecedented (from space)
wide field of view of 0.57 sq. deg. This exquisite image quality has
the potential to produce high-precision astrometry for point sources
once the undersampling of Euclid's cameras is taken into account by
means of accurate, effective point spread function (ePSF) modelling.
We present a complex, detailed workflow to simultaneously solve for
the geometric distortion (GD) and model the undersampled ePSFs of the
Euclid detectors. Our procedure was successfully developed and tested
with data from the Early Release Observations (ERO) programme focused
on the nearby globular cluster NGC 6397. Our final one-dimensional
astrometric precision for a well-measured star just below saturation
is 0.7mas (0.007pixel) for the Visible Instrument (VIS) and 3mas
(0.01pixel) for the Near-Infrared Spectrometer and Photometer (NISP).
Finally, we present a specific scientific application of this
high-precision astrometry: the combination of Euclid and Gaia data to
compute proper motions and study the internal kinematics of NGC 6397.
Future work, when more data become available, will allow for a better
characterisation of the ePSFs and GD corrections that are derived
here, along with assessment of their temporal stability, and their
dependencies on the spectral energy distribution of the sources as
seen through the wide-band filters of Euclid.
Description:
Astro-photometric catalogs and stacked images of NGC 6397. The
astrometrized stacked images do not currently take into account for
tangent-plane-projection effects. Also, fluxes are not properly
resampled. Thus, these images are meant for visual reference only and
not for scientific investigations.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
ngc6397.dat 358 474706 NGC 6397 astro-photometric catalog
list.dat 109 4 List of fits images
fits/* . 4 Individual fits images
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See also:
J/A+A/490/777 : Abundances of Population II stars in NGC6397 (Lind+, 2008)
J/A+A/503/545 : Equivalent widths of Li, Na, Fe, Ca in NGC6397 (Lind+, 2009)
J/A+A/505/L13 : Lithium in globular NGC 6397 (Gonzalez Hernandez+, 2009)
J/ApJ/709/241 : X-rays sources in NGC 6397 (Bogdanov+, 2010)
J/A+A/527/A148 : NGC6397 red giants chemical composition (Lind+, 2011)
J/ApJ/754/91 : Abundances and velocities of NGC 6397 stars (Lovisi+, 2012)
J/A+A/588/A148 : NGC 6397 stars MUSE spectra (Husser+, 2016)
J/MNRAS/468/2816 : NGC6397 low-mass variable stars (Martinazzi+, 2017)
J/MNRAS/475/257 : AGB subpopulations in NGC 6397 (MacLean+, 2018)
J/A+A/635/A161 : NGC6397 stars measured atmospheric parameters (Jain+, 2020)
J/A+A/690/A371 : NGC 6121 and NGC 6397 JWST/NIRISS data (Libralato+, 2024)
Byte-by-byte Description of file: ngc6397.dat
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Bytes Format Units Label Explanations
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1- 14 F14.10 deg RAdeg Right Ascension (ICRS) at Ep=2023 (RAdeg)
16- 29 F14.10 deg DEdeg Declination (ICRS) at Ep=2023 (DEdeg)
31- 36 I6 --- IDvis ID number of the source (IDvis)
38- 47 F10.4 100mas/pix XIE VIS X master-frame position (Xvis)
49- 58 F10.4 100mas/pix YIE VIS Y master-frame position (Yvis)
60- 66 F7.4 mag IEmag Calibrated VIS IE (550-900nm) magnitude
(mvis) (1)
68- 73 F6.4 100mas/pix e_XIE VIS X position rms (sxvis) (5)
75- 80 F6.4 100mas/pix e_YIE VIS Y position rms (syvis) (5)
82- 87 F6.4 mag e_IEmag VIS IE magnitude rms (smvis) (5)
89- 94 F6.4 --- q_IEmag VIS IE quality-of-PSF-fit parameter
(qvis) (5)
96 I1 --- nfIE Number of individual VIS IE exposures
in which an object was found (nfvis) (5)
98 I1 --- nuIE Number of individual VIS IE exposures
used to measure an object (nuvis) (5)
100-109 F10.4 300mas/pix XYE NISP YE X master-frame position
(xnispy) (6)
111-120 F10.4 300mas/pix YYE NISP YE Y master-frame position
(ynispy) (6)
122-128 F7.4 mag YEmag ?=0 Calibrated NISP YE (10866.24Å)
magnitude (mnispy) (6) (2)
130-135 F6.4 300mas/pix e_XYE ?=0 NISP YE X position rms
(sxnispy) (6) (5)
137-142 F6.4 300mas/pix e_YYE ?=0 NISP YE Y position rms
(synispy) (6) (5)
144-149 F6.4 mag e_YEmag ?=0 NISP YE magnitude rms
(smnispy) (6) (5)
151-156 F6.4 --- q_YEmag ?=0 NISP YE quality-of-PSF-fit
parameter (qnispy) (6) (5)
158 I1 --- nfYE Number of individual NISP YE exposures
in which an object was found
(nfnispy) (6) (5)
160 I1 --- nuYE Number of individual NISP YE exposures
used to measure an object
(nunispy) (6) (5)
162-171 F10.4 300mas/pix XJE NISP JE X master-frame position
(xnispj) (6)
173-182 F10.4 300mas/pix YJE NISP JE X master-frame position
(ynispj) (6)
184-190 F7.4 mag JEmag ?=0 Calibrated NISP JE (13766.64Å)
magnitude (mnispj) (6) (3)
192-197 F6.4 300mas/pix e_XJE ?=0 NISP JE X position rms
(sxnispj) (6) (5)
199-204 F6.4 300mas/pix e_YJE ?=0 NISP JE Y position rms
(synispj) (6) (5)
206-211 F6.4 mag e_JEmag ?=0 NISP JE magnitude rms
(smnispj) (6) (5)
213-218 F6.4 --- q_JEmag ?=0 NISP JE quality-of-PSF-fit
parameter (qnispj) (6) (5)
220 I1 --- nfJE Number of individual NISP JE exposures
in which an object was found
(nfnispj) (6)(5)
222 I1 --- nuJE Number of individual NISP JE exposures
used to measure an object
(nunispj) (6)(5)
224-233 F10.4 300mas/pix XHE NISP HE X master-frame position
(xnisph) (6)
235-244 F10.4 300mas/pix YHE NISP HE X master-frame position
(ynisph) (6)
246-252 F7.4 mag HEmag ?=0 Calibrated NISP HE (17825.15Å)
magnitude (mnisph) (6) (4)
254-259 F6.4 300mas/pix e_XHE ?=0 NISP HE X position rms
(sxnisph) (6) (5)
261-266 F6.4 300mas/pix e_YHE ?=0 NISP HE Y position rms
(synisph) (6) (5)
268-273 F6.4 mag e_HEmag ?=0 NISP HE magnitude rms
(smnisph) (6) (5)
275-280 F6.4 --- q_HEmag ?=0 NISP HE quality-of-PSF-fit
parameter (qnisph) (6) (5)
282 I1 --- nfHE Number of individual NISP HE exposures
in which an object was found
(nfnisph) (6)(5)
284 I1 --- nuHE Number of individual NISP HE exposures
used to measure an object
(nunisph) (6)(5)
286-294 F9.5 mas/yr pmRA ?=0 Proper motion along RA*cos(DE)
(pmRA) (7)
296-304 F9.5 mas/yr pmDE ?=0 Proper motion along Decliantion
(pmDE) (7)
306-313 F8.5 mas/yr e_pmRA ?=0 Error on the proper motion along
RA*cos(DE) (pmRA) (7)
315-321 F7.5 mas/yr e_pmDE ?=0 Error on the proper motion along
Declination (pmDE) (7)
323-331 F9.5 mas/yr pmRAc ?=0 Proper motion along RA*cos(DE)
corrected for the color-dependent
systematic (pmRAc) (7)
333-341 F9.5 mas/yr pmDEc ?=0 Proper motion along Declination
corrected for the color-dependent
systematic (pmDEc) (7)
343-350 F8.5 mas/yr e_pmRAc ?=0 Error on the proper motion along
RA*cos(DE) corrected for the
color-dependent systematic (pmRAc) (7)
352-358 F7.5 mas/yr e_pmDEc ?=0 Error on the proper motion along
Declination corrected for the
color-dependent systematic (pmDEc) (7)
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Note (1): Stars saturated in the VIS IE catalog have a magnitude ≤ ∼18.8.
Note (2): Stars saturated in the NISP YE catalog have a magnitude ≤ ∼16.2.
Note (3): Stars saturated in the NISP JE catalog have a magnitude ≤ ∼16.5.
Note (4): Stars saturated in the NISP HE catalog have a magnitude ≤ ∼16.5.
Note (5): Saturated stars have positional rms, magnitude rms,
quality-of-PSF-fit and/or proper motions that can be set to a value greater or
equal to 0. We advise extreme caution when dealing with saturated stars.
Note (6): Stars not measured in a NISP filter have all the corresponding
parameters set to 0.
Note (7): Stars without a proper-motion measurement have proper motions and
corresponding errors set to 0.
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 9 F9.5 deg RAdeg Right Ascension of center (J2000)
10- 18 F9.5 deg DEdeg Declination of center (J2000)
20- 22 F3.1 arcsec/pix scale Scale of the image
24- 28 I5 --- Nx Number of pixels along X-axis
30- 34 I5 --- Ny Number of pixels along Y-axis
36- 42 I7 Kibyte size Size of FITS file
44- 73 A30 --- FileName Name of FITS file, in subdirectory fits
75-109 A35 --- Title Title of the FITS file
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Acknowledgements:
Mattia Libralato, mattia.libralato(at)inaf.it
(End) Patricia Vannier [CDS] 04-Nov-2024