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Title: NGC 6811: AN INTERMEDIATE-AGE CLUSTER IN THE KEPLER FIELD

Abstract

NGC 6811 is one of the four open clusters located in the Kepler spacecraft field of view. We obtained UBVRI photometry of the cluster on six nights (four of them photometric) with the 1.08 m Hall and 1.83 m Perkins telescopes at Lowell Observatory. The mean photometric precision ranges from better than 0.01 mag in the V, B - V, V - R, and V - I indices among stars brighter than magnitude 15 to about 0.05 mag for U - B at magnitude 18. We followed a Bayesian statistical approach using the Markov Chain Monte Carlo algorithm to determine the cluster reddening, distance, age, and iron content from a maximum-likelihood fit to stellar isochrones. Using the Yale-Yonsei isochrones, we derived E(B - V) 0.066 {+-} 0.025, (m - M){sub V} = 10.13 {+-} 0.19, age = 1.06 {+-} 0.19 Gyr, and Z = 0.012 {+-} 0.004 ([Fe/H] = -0.18); with the Padova isochrones, we found E(B - V) = 0.081 {+-} 0.015, (m - M){sub V} = 10.31 {+-} 0.11, age = 0.94 {+-} 0.08 Gyr, and Z = 0.012 {+-} 0.002 ([Fe/H] = -0.20). The uncertainties include possible errors in the photometric zero points of {+-}0.01 mag, butmore » do not include uncertainties in the models. Taking into account the differences between the two sets of models, we find the best estimate for the cluster parameters to be E(B - V) = 0.074 {+-} 0.024, (m - M){sub V} = 10.22 {+-} 0.18, age = 1.00 {+-} 0.17 Gyr, and Z = 0.012 {+-} 0.004 ([Fe/H] = -0.19).« less

Authors:
;  [1];  [2];  [3]
  1. Astronomy Department, Boston University, Boston, MA 02215 (United States)
  2. Space Science Institute, Boulder, CO 80301 (United States)
  3. Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States)
Publication Date:
OSTI Identifier:
22089737
Resource Type:
Journal Article
Journal Name:
Astronomical Journal (New York, N.Y. Online)
Additional Journal Information:
Journal Volume: 145; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1538-3881
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ALGORITHMS; ASTRONOMY; ASTROPHYSICS; COSMOLOGY; DATA ANALYSIS; DIAGRAMS; DISTANCE; HYDROGEN; IRON; MARKOV PROCESS; MAXIMUM-LIKELIHOOD FIT; MONTE CARLO METHOD; PHOTOMETRY; STAR CLUSTERS; STARS; TELESCOPES

Citation Formats

Janes, Kenneth, Hoq, Sadia, Barnes, Sydney A., and Meibom, Soren. NGC 6811: AN INTERMEDIATE-AGE CLUSTER IN THE KEPLER FIELD. United States: N. p., 2013. Web. doi:10.1088/0004-6256/145/1/7.
Janes, Kenneth, Hoq, Sadia, Barnes, Sydney A., & Meibom, Soren. NGC 6811: AN INTERMEDIATE-AGE CLUSTER IN THE KEPLER FIELD. United States. https://doi.org/10.1088/0004-6256/145/1/7
Janes, Kenneth, Hoq, Sadia, Barnes, Sydney A., and Meibom, Soren. 2013. "NGC 6811: AN INTERMEDIATE-AGE CLUSTER IN THE KEPLER FIELD". United States. https://doi.org/10.1088/0004-6256/145/1/7.
@article{osti_22089737,
title = {NGC 6811: AN INTERMEDIATE-AGE CLUSTER IN THE KEPLER FIELD},
author = {Janes, Kenneth and Hoq, Sadia and Barnes, Sydney A. and Meibom, Soren},
abstractNote = {NGC 6811 is one of the four open clusters located in the Kepler spacecraft field of view. We obtained UBVRI photometry of the cluster on six nights (four of them photometric) with the 1.08 m Hall and 1.83 m Perkins telescopes at Lowell Observatory. The mean photometric precision ranges from better than 0.01 mag in the V, B - V, V - R, and V - I indices among stars brighter than magnitude 15 to about 0.05 mag for U - B at magnitude 18. We followed a Bayesian statistical approach using the Markov Chain Monte Carlo algorithm to determine the cluster reddening, distance, age, and iron content from a maximum-likelihood fit to stellar isochrones. Using the Yale-Yonsei isochrones, we derived E(B - V) 0.066 {+-} 0.025, (m - M){sub V} = 10.13 {+-} 0.19, age = 1.06 {+-} 0.19 Gyr, and Z = 0.012 {+-} 0.004 ([Fe/H] = -0.18); with the Padova isochrones, we found E(B - V) = 0.081 {+-} 0.015, (m - M){sub V} = 10.31 {+-} 0.11, age = 0.94 {+-} 0.08 Gyr, and Z = 0.012 {+-} 0.002 ([Fe/H] = -0.20). The uncertainties include possible errors in the photometric zero points of {+-}0.01 mag, but do not include uncertainties in the models. Taking into account the differences between the two sets of models, we find the best estimate for the cluster parameters to be E(B - V) = 0.074 {+-} 0.024, (m - M){sub V} = 10.22 {+-} 0.18, age = 1.00 {+-} 0.17 Gyr, and Z = 0.012 {+-} 0.004 ([Fe/H] = -0.19).},
doi = {10.1088/0004-6256/145/1/7},
url = {https://www.osti.gov/biblio/22089737}, journal = {Astronomical Journal (New York, N.Y. Online)},
issn = {1538-3881},
number = 1,
volume = 145,
place = {United States},
year = {Tue Jan 01 00:00:00 EST 2013},
month = {Tue Jan 01 00:00:00 EST 2013}
}