NEW DENSITY PROFILE AND STRUCTURAL PARAMETERS OF THE COMPLEX STELLAR SYSTEM TERZAN 5

Journal Article · Sat Jul 10 00:00:00 EDT 2010 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/717/2/653· OSTI ID:21455230

Lanzoni, B; Ferraro, F R; Dalessandro, E; Mucciarelli, A; Miocchi, P ^[1]; Beccari, G ^[2]; Bellazzini, M; Origlia, L ^[3]; Rich, R M ^[4]; Valenti, E ^[5]; Rood, R T ^[6]; Ransom, S M ^[7]

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1. Dipartimento di Astronomia, Universita degli Studi di Bologna, via Ranzani 1, I-40127 Bologna (Italy)
2. ESA, Space Science Department, Keplerlaan 1, 2200 AG Noordwijk (Netherlands)
3. INAF-Osservatorio Astronomico di Bologna, Via Ranzani 1, 40127 Bologna (Italy)
4. Department of Physics and Astronomy, Math-Sciences 8979, UCLA, Los Angeles, CA 90095-1562 (United States)
5. P. Universidad Catolica de Chile, Departamento de Astronomia y Astrofisica, Casilla 306, Santiago 22 (Chile)
6. Astronomy Department, University of Virginia, P.O. Box 400325, Charlottesville, VA, 22904 (United States)
7. National Radio Astronomy Observatory, Charlottesville, VA 22903 (United States)

Terzan 5 is a globular cluster-like stellar system in the Galactic bulge which has been recently found to harbor two stellar populations with different iron content and probably different ages. This discovery suggests that Terzan 5 may be the relic of a primordial building block that contributed to the formation of the Galactic bulge. Here we present a re-determination of the structural parameters (center of gravity, density and surface brightness profiles, total luminosity, and mass) of Terzan 5, as obtained from the combination of high-resolution (ESO-MAD and Hubble Space Telescope ACS-WFC) and wide-field (ESO-WFI) observations. We find that Terzan 5 is significantly less concentrated and more massive than previously thought. Still it has the largest collision rate of any stellar aggregate in the Galaxy. We discuss the impact of these findings on the exceptional population of millisecond pulsars harbored in this stellar system.

• OSTI ID: 21455230
• Journal Information: Astrophysical Journal, Vol. 717, Issue 2; Other Information: DOI: 10.1088/0004-637X/717/2/653; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
GALAXIES
GRAVITATION
LUMINOSITY
PULSARS
STAR EVOLUTION
TELESCOPES
COSMIC RADIO SOURCES
EVOLUTION
OPTICAL PROPERTIES
PHYSICAL PROPERTIES