VLT and ACS observations of RDCS J1252.9-2927: dynamical structure and galaxy populations in a massive cluster at z=1.237
| العنوان: | VLT and ACS observations of RDCS J1252.9-2927: dynamical structure and galaxy populations in a massive cluster at z=1.237 |
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| المؤلفون: | Paolo Tozzi, Nicole Homeier, G. Hartig, Garth D. Illingworth, Brad Holden, Leopoldo Infante, R. Gobat, Ricardo Demarco, Marc Postman, V. Mainieri, Roderik Overzier, Veronica Motta, Alessandro Rettura, Mario Nonino, Narciso Benítez, V. Strazzullo, Piero Rosati, A. van der Wel, Myungkook J. Jee, W. Zheng, Christopher Lidman, Andrew Zirm, Holland C. Ford, John P. Blakeslee, Marisa Girardi, Simona Mei, Mark Clampin, Felipe Menanteau, Spencer A. Stanford |
| المساهمون: | Demarco, R., Rosati, P., Lidman, C., Girardi, Marisa, Nonino, M., Rettura, A., Strazzullo, Veronica, van der Wel, A., Ford, H. C., Mainieri, V., Holden, B. P., Stanford, S. A., Blakeslee, J. P., Gobat, R., Postman, M., Tozzi, P., Overzier, R. A., Zirm, A. W., Benítez, N., Homeier, N. L., Illingworth, G. D., Infante, L., Jee, M. J., Mei, S., Menanteau, F., Motta, V., Zheng, W., Clampin, M., Hartig, G. |
| المصدر: | ASTROPHYSICAL JOURNAL |
| سنة النشر: | 2007 |
| مصطلحات موضوعية: | J1252.9-2927), Structure formation, clusters : general [galaxies], H-ALPHA, Dark matter, FOS: Physical sciences, DEEP-FIELD-NORTH, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Advanced Camera for Surveys, 0103 physical sciences, Cluster (physics), COLOR-MAGNITUDE RELATION, STAR-FORMING GALAXIES, TO-LIGHT RATIOS, galaxy clusters, Astrophysics::Solar and Stellar Astrophysics, 010306 general physics, 010303 astronomy & astrophysics, Galaxy cluster, Astrophysics::Galaxy Astrophysics, Physics, clusters : individual (ClG [galaxies], SCALE-INDEPENDENT METHOD, Astrophysics (astro-ph), Astronomy and Astrophysics, HUBBLE-SPACE-TELESCOPE, HIGH-REDSHIFT CLUSTERS, Redshift, Galaxy, Stars, COMPACT BLUE GALAXIES, Physics and Astronomy, Space and Planetary Science, MORPHOLOGY-DENSITY RELATION |
| الوصف: | We present results from an extensive spectroscopic survey, carried out with VLT FORS, and from an extensive multiwavelength imaging data set from the HST Advanced Camera for Surveys and ground based facilities, of the cluster of galaxies RDCS J1252.9-2927. We have spectroscopically confirmed 38 cluster members in the redshift range 1.22 < z < 1.25. A cluster median redshift of z=1.237 and a rest-frame velocity dispersion of 747^{+74}_{-84} km/s are obtained. Using the 38 confirmed redshifts, we were able to resolve, for the first time at z > 1, kinematic structure. The velocity distribution, which is not Gaussian at the 95% confidence level, is consistent with two groups that are also responsible for the projected east-west elongation of the cluster. The groups are composed of 26 and 12 galaxies with velocity dispersions of 486^{+47}_{-85} km/s and 426^{+57}_{-105} km/s, respectively. The elongation is also seen in the intracluster gas and the dark matter distribution. This leads us to conclude that RDCS J1252.9-2927 has not yet reached a final virial state. We extend the analysis of the color-magnitude diagram of spectroscopic members to more than 1 Mpc from the cluster center. The scatter and slope of non-[OII]-emitting cluster members in the near-IR red sequence is similar to that seen in clusters at lower redshift. Furthermore, most of the galaxies with luminosities greater than ~ K_s*+1.5 do not show any [OII], indicating that these more luminous, redder galaxies have stopped forming stars earlier than the fainter, bluer galaxies. Our observations provide detailed dynamical and spectrophotometric information on galaxies in this exceptional high-redshift cluster, delivering an in-depth view of structure formation at this epoch only 5 Gyr after the Big Bang. 29 pages. 16 figures. ApJ accepted. Tables 2,3 and 5, figure 1 and the full figure 5 will be available in the paper and electronic editions from ApJ. v2: minor corrections to the abstract and text to match the Journal's version |
| وصف الملف: | STAMPA; application/pdf |
| اللغة: | English |
| تدمد: | 0004-637X 1538-4357 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::14355410a64d0f3a17b8fdf6be88c990 http://arxiv.org/abs/astro-ph/0703153 |
| حقوق: | OPEN |
| رقم الأكسشن: | edsair.doi.dedup.....14355410a64d0f3a17b8fdf6be88c990 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 0004637X 15384357 |
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