DOI QR코드

DOI QR Code

THE STAR CLUSTER SYSTEM OF THE MERGING GALAXY NGC 1487

  • Published : 2005.09.01

Abstract

We present a photometric study of the star cluster system in the merging galaxy NGC 1487, based on the BI photometry obtained from the F450W and F814W images in the HST /WFPC2 archive data. We have found about 560 star cluster candidates in NGC 1487, using the morphological parameters of the objects. We have investigated several photometric characteristics of the clusters: color-magnitude diagrams (CMDs), color distribution, spatial distribution, age, size and luminosity function. The CMD of the bright clusters with 18.5 < B < 24 mag in NGC 1487 shows three major populations of clusters: a blue cluster population with $(B-I){\le}0.45$, an intermediate-color cluster population with $0.45<(B-I){\le}1.55$, and a red cluster population with (B - I) > 1.55. The intermediate-color population is the most dominant among the three populations. The brightest clusters in the blue and intermediate- color populations are as bright as $B{\approx}18mag$ ($M_B{\approx}-12mag$), which are three magnitudes brighter than those in the red population. The blue and intermediate-color clusters are strongly concentrated on the bright condensations, while the red clusters are relatively more scattered over the galaxy. The CMD of these clusters is found to be remarkably similar to that of the clusters in the famous interacting system M51. From this we suggest that the intermediate-color clusters were, probably, formed during the merging process which occurred about 500 Myrs ago.

Keywords

References

  1. AJ v.114 The Peculiar Galaxy NGC 1487 Aguero, E.L.;Paolantonio, S. https://doi.org/10.1086/118456
  2. A&AS v.117 SExtractor: Software for source extraction Bertin, E.;Arnouts, S. https://doi.org/10.1051/aas:1996164
  3. MNRAS v.334 Stellar population synthesis at the resolution of 2003 Bruzual, G.;Charlot, S.
  4. Third Reference Catalogue of bright galaxies, RC3 de Vaucouleurs, G.;de Vaucouleurs, A.;Corwin, J.R.;Buta, R.J.;Paturel, G.;Fouque, P.
  5. PASP v.112 WFPC2 Stellar Photometry with HSTPHOT Dolphin, A.E. https://doi.org/10.1086/316630
  6. PASP v.112 The Charge-Transfer Effciency and Calibration of WFPC2 Dolphin, A.E.
  7. AJ v.123 HUBBLE SPACE TELESCOPE Survey of Clusters in Nearby Galaxies. I. Detection and Photometry Dolphin, A.E.;Kennicutt, R.C. https://doi.org/10.1086/338097
  8. AJ v.124 HUBBLE SPACE TELESCOPE Survey of Clusters in Nearby Galaxies. II. Statistical Analysis of Cluster Populations Dolphin, A.E.;Kennicutt, R.C. https://doi.org/10.1086/340807
  9. HSTphot User's Guide Dolphin, A.E.
  10. AJ v.112 A Catalog of Parameters for Globular Clusters in the Milky Way Harris, W.E. https://doi.org/10.1086/118116
  11. PASP v.107 The Photometric Performance and Calibration of WFPC2 Holtzman, J.A.;Burrows, C.J.;Casertano, S.;Hester, J.J.;Trauger, J.T.;Watson, A.M.;Worthey, G. https://doi.org/10.1086/133664
  12. AJ v.127 Hubble Space Telescope Observations of cD Galaxies and Their Globular Cluster Systems Jordan, A.;Cote, P.;West, M.J.;Marzke, R.O.;Minniti, D. https://doi.org/10.1086/379965
  13. AJ v.126 Massive Star Clusters in Ongoing Galaxy Interactions: Clues to Cluster Formation Keel, W.C.;Borne, K.D. https://doi.org/10.1086/377482
  14. AJ Properties of Resolved Star Clusters in M51 Lee, M.G.;Chandar, R.;Whitmore, B.
  15. AJ v.115 Magellanic Cloud Cepheids-Abundances Luck, R.E.;Moffet, T.J.;Barnes, T.G.;Gieren, W.P. https://doi.org/10.1086/300227
  16. MNRAS v.338 Surface brightness profiles and structural parameters for 53 rich stellar clusters in the Large Magellanic Cloud Mackey, A.D.;Gilmore, G.F. https://doi.org/10.1046/j.1365-8711.2003.06021.x
  17. AJ v.114 The Star Cluster System of the Merger Remnant NGC 7252 Miller, B.W.;Whitmore, B.C.;Schweizer, F.;Fall, S.M. https://doi.org/10.1086/118655
  18. A Revised Shapley-Ames Catalogue Sandage, A.R.;Tammann, G.A.
  19. ApJ v.500 Maps of Dust Infrared Emission for Use in Estimation of Reddening and Cosmic Microwave Background Radiation Foregrounds Schlegel, D.J.;Finkeiner, D.P.;Davis, M. https://doi.org/10.1086/305772
  20. AJ v.112 Hubble Space Telescope Observations of Candidate Young Globular Clusters and Stellar Associations in the Recent Merger Remnant NGC 3921 Schweizer, F.;Miller, B.W. https://doi.org/10.1086/118146
  21. AJ v.127 Star Clusters in Virgo and Fornax Dwarf Irregular Galaxies Seth, A.;Olsen, K.;Miller, B.;Lotz, J.;Telford, R. https://doi.org/10.1086/380946
  22. A Decade of Hubble Space Telescope Proceeding of the Space Telescope Science Institute Symposium v.14 no.153 Whitmore, B.C.;Livio, M.(ed.);Noll, K.(ed.);Stiavelli, M.(ed.)
  23. AJ v.118 The Formation and Evolution of Candidate Young Globular Clusters in NGC 3256 Zepf, S.E.;Ashman, K.M.;English, J.;Freeman, K.C.;Sharples, R.M. https://doi.org/10.1086/300961

Cited by

  1. AGES OF M33 STAR CLUSTERS BASED ON THEHUBBLE SPACE TELESCOPE/WFPC2 PHOTOMETRY vol.700, pp.1, 2009, https://doi.org/10.1088/0004-637X/700/1/103
  2. UNDER PRESSURE: STAR CLUSTERS AND THE NEUTRAL HYDROGEN MEDIUM OF TIDAL TAILS vol.768, pp.2, 2013, https://doi.org/10.1088/0004-637X/768/2/194
  3. STAR CLUSTERS IN THE TIDAL TAILS OF INTERACTING GALAXIES: CLUSTER POPULATIONS ACROSS A VARIETY OF TAIL ENVIRONMENTS vol.731, pp.2, 2011, https://doi.org/10.1088/0004-637X/731/2/93