J/A+A/548/A129 HST photometry in NGC 6822 (Fusco+, 2012)
Distance and reddening of the Local Group dwarf irregular galaxy NGC 6822.
Fusco F., Buonanno R., Bono G., Cassisi S., Monelli M., Pietrinferni A.
<Astron. Astrophys. 548, A129 (2012)>
=2012A&A...548A.129F 2012A&A...548A.129F
ADC_Keywords: Galaxies, photometry; Photometry, HST; Stars, distances
Keywords: galaxies: dwarf - Local Group - galaxies: individual: NGC 6822
Abstract:
On the basis of a new photometric analysis of the Local Group dwarf
irregular galaxy NCG 6822 based on observations obtained with the
Advanced Camera for Surveys onboard the Hubble Space Telescope, we
have obtained a new estimate of the extinction of two fields located
in the southeast region of the galaxy. Because of significant
differences in the distance estimates to NGC 6822 available in
literature, we decided to provide an independent determination of the
distance to this galaxy based on an updated and self-consistent
theoretical calibration of the tip of the red giant branch brightness.
As a result we newly determined the distance to NGC 6822 to be equal
to (m-M)0=23.54±0.05, and compared our measurement with the most
recent determinations of this distance.
Description:
We performed HST photometry on three fields in the south-east region
of NGC 6822 galaxy. The resulting catalogues contain ∼140,000,
∼42,000, ∼12,000 stars, from the innermost to the outermost field.
Data were calibrated using the VEGAMAG system. Data are stored in
three files, one for each field:
central field: n6822_0.dat
middle field: n6822_a.dat
outer field: n6822_b.dat
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
n6822_0.dat 123 139089 Photometric catalogue in F475W and F814W HST
bands for the innermost field
n6822_a.dat 123 42279 Photometric catalogue in F475W and F814W HST
bands for the middle field
n6822_b.dat 123 11683 Photometric catalogue in F475W and F814W HST
bands for the outermost field
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See also:
J/AJ/109/173 : BVR photometry of NGC 6822 (Marconi+ 1995)
J/AJ/110/2715 : UBV photometry in NGC 6822, M31 and M33 (Massey+ 1995)
J/AJ/121/2020 : CTIO and WFPC2 photometry in NGC 6822 (Bianchi+, 2001)
J/AJ/123/832 : C star population in NGC 6822 (Letarte+, 2002)
J/A+A/429/837 : IJKs photometry of late-type stars in NGC 6822 (Cioni+, 2005)
J/A+A/431/1189 : BV photometry of NGC 6822 variables (Baldacci+, 2005)
J/A+A/454/717 : NGC 6822 near-IR photometry of C and AGB stars (Kang+, 2006)
J/A+A/456/905 : JKs, i'g'r' photometry of C stars in NGC 6822 (Demers+, 2006)
J/AJ/128/2815 : ARAUCARIA: NGC 6822 Cepheid variables (Pietrzynski+, 2004)
J/AJ/132/378 : HST and UV photometry of NGC 6822 (Bianchi+, 2006)
J/AJ/132/1372 : Chandra observation of NGC 6822 (Tennant+, 2006)
J/ApJ/647/1056 : ARAUCARIA: NGC 6822 Cepheid variables (Gieren+, 2006)
J/A+A/450/873 : NGC 6822 bright variables VI phot. (Mennickent+, 2008)
J/A+A/495/447 : PN and HII regions in NGC6822 (Hernandez-Martinez+, 2009)
J/A+A/537/A108 : NGC 6822 AGB spectroscopic catalogue (Kacharov+, 2012)
J/A+A/540/A135 : AGB population of NGC 6822 (Sibbons+, 2012)
Byte-by-byte Description of file: n6822_0.dat n6822_a.dat n6822_b.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- ID Star identification number
8- 15 F8.3 pix Xpos X coordinate in pixels
17- 24 F8.3 pix Ypos Y coordinate in pixels
28- 33 F6.3 mag F475W Magnitude in HST/ACS F475W band
37- 42 F6.4 mag e_F475W Error associated to F475W magnitude
46- 51 F6.3 mag F814W Magnitude in HST/ACS F814W band
55- 60 F6.4 mag e_F814W Error associated to F814W magnitude
63- 69 F7.4 --- Chi Mean value of the χ image-quality index
72- 78 F7.4 --- Sharp Mean value of the sharp image-quality index
(<0 for cosmic rays, >0 for resolved sources)
82- 83 I2 h RAh Right ascension (J2000)
87- 88 I2 min RAm Right ascension (J2000)
91- 97 F7.4 sec RAs Right ascension (J2000)
101 A1 --- DE- Declination sign (J2000)
102-103 I2 deg DEd Declination (J2000)
108-109 I2 arcmin DEm Declination (J2000)
113-118 F6.3 arcsec DEs Declination (J2000)
123 I1 --- Chip [1/2] Chip of the camera (1=WFC1, 2=WFC2)
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Acknowledgements:
Federica Fusco, federica.fusco(at)roma2.infn.it
(End) Federica Fusco [Rome Tor Vergata Univ.] Patricia Vannier [CDS] 14-Nov-2012