J/ApJ/861/99 HSTPROMO cat. VI. Improved analysis of NGC362 (Libralato+, 2018)
Hubble Space Telescope Proper Motion (HSTPROMO) catalogs of Galactic globular
cluster.
VI. Improved data reduction and internal-kinematic analysis of NGC 362.
Libralato M., Bellini A., van der Marel R.P., Anderson J., Watkins L.L.,
Piotto G., Ferraro F.R., Nardiello D., Vesperini E.
<Astrophys. J., 861, 99 (2018)>
=2018ApJ...861...99L 2018ApJ...861...99L
ADC_Keywords: Clusters, globular ; Proper motions; Photometry, HST;
Photometry, VRI
Keywords: globular clusters: individual (NGC 362) ; proper motions ;
stars: kinematics and dynamics ; stars: Population II ;
techniques: photometric
Abstract:
We present an improved data-reduction technique to obtain
high-precision proper motions (PMs) of globular clusters (GCs) using
Hubble Space Telescope data. The new reduction is superior to the one
presented in the first paper of this series for the faintest sources
in very crowded fields. We choose the GC NGC 362 as a benchmark to
test our new procedures. We measure PMs of 117450 sources in the
field, showing that we are able to obtain a PM precision better than
10µas/yr for bright stars. We make use of this new PM catalog of
NGC 362 to study the cluster's internal kinematics. We investigate the
velocity dispersion profiles of the multiple stellar populations
hosted by NGC 362 and find new pieces of information on the kinematics
of first- and second- generation stars. We analyze the level of energy
equipartition of the cluster and find direct evidence for its
post-core-collapsed state from kinematic arguments alone. We refine
the dynamical mass of the blue stragglers (BSs) and study possible
kinematic differences between BSs formed by collisions and mass
transfer. We also measure no significant cluster rotation in the plane
of the sky. Finally, we measure the absolute PM of NGC 362 and of the
background stars belonging to the Small Magellanic Cloud, finding a
good agreement with previous estimates in the literature. We make the
PM catalog publicly available.
Description:
We made use of all suitable HST images covering the central field of
the cluster between 2003 and 2012 September with the Advanced Camera
for Survey (ACS) and the Wide Field Camera 3 (WFC3); i.e. GO 10005,
10401, 10615, 10775, 12516 and 12605.
Objects:
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RA (ICRS) DE Designation(s)
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01 03 14.26 -70 50 55.6 NGC 362 = Cl Melotte 4
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 151 117450 The astrometric catalog of NGC 362
table3.dat 51 117450 The photometric catalog of NGC 362 for filter F606W
table4.dat 50 117450 The photometric catalog of NGC 362 for filter F814W
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See also:
B/hst : HST Archived Exposures Catalog (STScI, 2007)
I/337 : Gaia DR1 (Gaia Collaboration, 2016)
VII/195 : Globular Clusters in the Milky Way (Harris, 1996)
J/A+AS/93/293 : Astrometry of globular clusters (47 Tuc) (Tucholke 1992)
J/AJ/106/1508 : Dynamics of globular cluster NGC 362 (Fischer+ 1993)
J/AJ/109/218 : Catalogue of globular cluster profiles (Trager+ 1995)
J/A+A/360/472 : Proper motions in omega Centauri (van Leeuwen+, 2000)
J/AJ/122/2569 : VI photometry of NGC 288, 362 and 1851 (Bellazzini+, 2001)
J/AJ/134/1298 : CaII EWs in 29 Galactic clusters (Carrera+, 2007)
J/A+A/463/589 : Variables stars in NGC 362 (Szekely+, 2007)
J/A+A/557/A138 : Detailed abundances in the GlC NGC 362 (Carretta+ 2013)
J/ApJ/797/115 : HSTPROMO I. Observations and NGC7078 results (Bellini+, 2014)
J/MNRAS/442/1663 : Velocities of red giants in the SMC (Dobbie+, 2014)
J/MNRAS/449/4038 : Li abundance of giants in 3 GCs (D'Orazi+, 2015)
J/ApJ/803/29 : HSTPROMO catalogs. II. Kinematic profiles (Watkins+, 2015)
J/ApJ/812/149 : HSTPROMO. III. Dynamical distances (Watkins+, 2015)
J/ApJ/827/12 : HSTPROMO cat. of GCs IV. Blue straggler stars (Baldwin+, 2016)
J/ApJ/832/99 : HK', CN & CH indexes in NGC 362 & NGC 6723 (Lim+, 2016)
J/AcA/66/307 : NGC 362 variable V light curves (Rozyczka+, 2016)
J/ApJ/842/6 : Astro-photom. catalog of the core of NGC 5139 (Bellini+, 2017)
J/ApJ/844/164 : HST astro-photom. analysis of NGC5139. III. (Bellini+, 2017)
J/ApJ/853/86 : HST large prog. on ω Centauri. II. (Bellini+, 2018)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 11 F11.8 deg RAdeg [15.69/15.9] Right Ascension (J2000)
13- 24 F12.8 deg DEdeg [-70.9/-70.8] Declination (J2000)
26- 34 F9.4 pix Xpix X coordinate in WFC3/UVIS pixel (0.04"/pixel)
36- 44 F9.4 pix Ypix Y coordinate in WFC3/UVIS pixel (0.04"/pixel)
46- 53 F8.4 mas/yr pmRA [-58/58.1] Raw proper motion along RA cos(DE)
55- 61 F7.4 mas/yr e_pmRA [0.004/20] Uncertainty in pmRA
63- 70 F8.4 mas/yr pmDE [-68.6/61] Raw proper motion along DE
72- 78 F7.4 mas/yr e_pmDE [0.005/19] Uncertainty in pmDE
80- 86 F7.4 --- chi2X [0.01/59.2] Reduced χ2 of X pixel fit
88- 94 F7.4 --- chi2Y [0.01/87.8] Reduced χ2 of Y pixel fit
96- 98 I3 --- NExp [5/106] Number of exposures star was found in
100-102 I3 --- NUse [4/106] Number of measurements used to fit
proper motion
104-110 F7.5 yr Base [1/9] Temporal baseline used
for proper motions
112-119 F8.4 mas/yr cpmRA [-58/58] Corrected proper motion
along RA cos(DE)
121-127 F7.4 mas/yr e_cpmRA [0.007/20] Uncertainty in cpmRA
129-136 F8.4 mas/yr cpmDE [-69/61] Corrected proper motion along DE
138-144 F7.4 mas/yr e_cpmDE [0.008/18.5] Uncertainty in cpmDE
146-151 I6 --- ID [54/149817] Star identifier
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 7 F7.4 mag F606Wmag [14.8/31.5] HST/ACS F606W band VEGA magnitude
9- 14 F6.4 mag e_F606Wmag [0.0001/10] RMS magnitude of F606Wmag
16- 20 F5.3 --- QFIT [0/1] The QFIT value; F606W band (G1)
22- 31 F10.5 --- o [0/1545] The o value; F606W band (G2)
33- 39 F7.4 --- RADXS [-9.9999/9.9999] The RADXS value;
F606W band (G3)
41 I1 --- Nf [1/4] Number of F606W-filter exposures
the star was found in
43 I1 --- Nu [1/4] Number of measurements used to compute
the photometric quantities in F606W filter
45- 51 F7.2 ct Sky [0/9999.9] Sky RMS in counts; F606W band
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 7 F7.4 mag F814Wmag [14.1/28.9] HST F814W band VEGA magnitude
9- 14 F6.4 mag e_F814Wmag [0.0001/10] RMS magnitude in F814Wmag
16- 20 F5.3 --- QFIT2 [0/1] The QFIT value; F814W band (G1)
22- 30 F9.5 --- o2 [0/276] The o value; F814W band (G2)
32- 38 F7.4 --- RADXS2 [-9.9999/9.9999] The RADXS value;
F814W band (G3)
40 I1 --- Nf2 [0/4] Number of F814W-filter exposures the
star was found in
42 I1 --- Nu2 [0/4] Number of measurements used to compute
the photometric quantities in F814W filter
44- 50 F7.2 ct Sky2 [0/9999.9] Sky RMS in counts; F814W band
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Global notes:
Note (G1): The QFIT represents the linear-correlation coefficient (similar to
the Pearson coefficient) between the values of the real pixels and
those of the PSF models. The closer to unity the QFIT is, the better
the PSF fit.
Note (G2): Ratio between the flux within the fitting radius due to
nearby neighbors and the stellar flux.
Note (G3): The RADXS value is the excess/deficiency of flux outside of
the fitting radius with respect to that predicted by the PSF. It is
particularly effective in separating faint stars from artifacts and
background galaxies.
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History:
From electronic version of the journal
References:
Bellini et al. Paper I. 2014ApJ...797..115B 2014ApJ...797..115B Cat. J/ApJ/797/115
Watkins et al. Paper II. 2015ApJ...803...29W 2015ApJ...803...29W Cat. J/ApJ/803/29
Watkins et al. Paper III. 2015ApJ...812..149W 2015ApJ...812..149W Cat. J/ApJ/812/149
Baldwin et al. Paper IV. 2016ApJ...827...12B 2016ApJ...827...12B Cat. J/ApJ/827/12
Bellini et al. Paper V. 2017ApJ...844..167B 2017ApJ...844..167B
Libralato et al. Paper VI. 2018ApJ...861...99L 2018ApJ...861...99L This catalog
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 15-Jul-2019