J/A+A/581/A72 ubvy photometry of NGC2419 (Frank+, 2015)
Stroemgren uvby photometry of the peculiar globular cluster NGC2419.
Frank M.J., Koch A., Feltzing S., Kacharov N., Wilkinson M.I., Irwin M.
<Astron. Astrophys. 581, A72 (2015)>
=2015A&A...581A..72F 2015A&A...581A..72F (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, globular ; Photometry, uvby
Keywords: globular clusters: individual: NGC 2419 - stars: abundances -
techniques: photometric
Abstract:
NGC 2419 is a peculiar Galactic globular cluster offset from the
others in the size-luminosity diagram, and showing several chemical
abundance anomalies. Here, we present Stromgren uvby photometry of
the cluster. Using the gravity- and metallicity-sensitive c1 and m1
indices, we identify a sample of likely cluster members extending well
beyond the formal tidal radius. The estimated contamination by cluster
non-members is only one per cent, making our catalogue ideally suited
for spectroscopic follow-up. We derive photometric [Fe/H] of red
giants, and depending on which metallicity calibration from the
literature we use, we find reasonable to excellent agreement with
spectroscopic [Fe/H], both for the cluster mean metallicity and for
individual stars. We demonstrate explicitly that the photometric
uncertainties are not Gaussian and this must be accounted for in any
analysis of the metallicity distribution function.
Description:
Imaging of NGC 2419 in the intermediate-band Stromgren filters u, b, v
and y was obtained in February 2012 using the Wide Field Camera (WFC)
at the 2.5m Isaac Newton Telescope (INT) at the Roque de los Muchachos
Observatory, La Palma, Spain. The resulting photometric catalog
containing 1197 detections in the unvignetted field of the camera,
passing basic quality cuts (magnitude uncertainty, sharpness, χ)
in all four filters is made available here. It covers NGC 2419 out to
about 25 arcmin, several times beyond its tidal radius, but is
incomplete in the cluster centre due to crowding.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.dat 153 1197 Photometry and stellar classification
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See also:
J/PASP/117/37 : BVRI photometry in NGC 2419, Pal 4, and Pal 14 (Saha+, 2005)
J/AJ/136/2259 : HST photometry of stars in NGC 2419 (Sandquist+, 2008)
J/ApJ/681/311 : Blue stragglers in NGC 2419 (Dalessandro+, 2008)
J/AJ/141/81 : NGC 2419 variable star population (Di Criscienzo+, 2011)
J/ApJ/738/186 : HST and DEIMOS measurements of NGC 2419 stars (Ibata+, 2011)
J/ApJ/740/60 : NGC2419 & NGC7099 RGB stars equivalent widths (Cohen+, 2011)
J/ApJ/760/86 : Equivalent widths for 13 NGC 2419 RGB stars (Cohen+, 2012)
J/MNRAS/431/1995 : Deep uVI photometry of NGC 2419 (Beccari+, 2013)
Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
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2- 3 I2 h RAh Right Ascension (J2000)
5- 6 I2 min RAm Right Ascension (J2000)
8- 13 F6.3 s RAs Right Ascension (J2000)
15 A1 --- DE- Declination sign (J2000)
17- 18 I2 deg DEd Declination (J2000)
20- 21 I2 arcmin DEm Declination (J2000)
23- 27 F5.2 arcsec DEs Declination (J2000)
29 I1 --- Chip WFC chip of source detection
31- 36 F6.1 --- X Chip x coordinate of detection
38- 43 F6.1 --- Y Chip x coordinate of detection
45- 50 F6.3 mag bmag Apparent magnitude in Stroemgren b filter
52- 56 F5.3 mag e_bmag Stroemgren b magnitude daophot uncertainty
58- 62 F5.2 --- bchi Stroemgren b magnitude daophot chi
64- 68 F5.2 --- bsharp Stroemgren b magnitude daophot sharpness
70- 75 F6.3 mag umag Apparent magnitude in Stroemgren u filter
77- 81 F5.3 mag e_umag Stroemgren u magnitude daophot uncertainty
83- 87 F5.2 --- uchi Stroemgren u magnitude daophot chi
89- 93 F5.2 --- usharp Stroemgren u magnitude daophot sharpness
95-100 F6.3 mag vmag Apparent magnitude in Stroemgren v filter
102-106 F5.3 mag e_vmag Stroemgren v magnitude daophot uncertainty
108-112 F5.2 --- vchi Stroemgren v magnitude daophot chi
114-118 F5.2 --- vsharp Stroemgren v magnitude daophot sharpness
120-125 F6.3 mag ymag Apparent magnitude in Stroemgren y filter
127-131 F5.3 mag e_ymag Stroemgren y magnitude daophot uncertainty
133-137 F5.2 --- ychi Stroemgren y magnitude daophot chi
139-143 F5.2 --- ysharp Stroemgren y magnitude daophot sharpness
145 I1 --- HBFlag [0,1] 1 if candidate horizontal branch star (1)
147 I1 --- RGBFlag [0,1] 1 if candidate red giant branch star (1)
149 I1 --- VariFlag [0,1] 1 if candidate variable star (1)
151 I1 --- RGBFlag2 [0,1] 1 if RGBFlag and passing metallicity
selection (2)
153 I1 --- RGBFlag3 [0,1] 1 if RGBFlag2 and passing ridgeline
selection (3)
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Note (1): selection according to Fig. 2 in the paper.
Note (2): selection according to Fig. 3 in the paper.
Note (3): selection according to Fig. 4 in the paper.
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Acknowledgements:
Matthias J. Frank, astro(at)matthiasfrank.net
(End) Matthias Frank [LSW, Univ. Heidelberg], Patricia Vannier [CDS] 08-Jul-2015