Skip to main content Accessibility help
×
Home
Hostname: page-component-559fc8cf4f-z4vvc Total loading time: 0.354 Render date: 2021-03-06T18:49:54.072Z Has data issue: true Feature Flags: { "shouldUseShareProductTool": true, "shouldUseHypothesis": true, "isUnsiloEnabled": true, "metricsAbstractViews": false, "figures": false, "newCiteModal": false, "newCitedByModal": true }

The globular cluster NGC 6642: evidence for a depleted mass function

Published online by Cambridge University Press:  18 January 2010

Eduardo Balbinot
Affiliation:
Departamento de Astronomia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil email: balbinot@if.ufrgs.br
Basílio X. Santiago
Affiliation:
Departamento de Astronomia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil email: balbinot@if.ufrgs.br
Eduardo Bica
Affiliation:
Departamento de Astronomia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil email: balbinot@if.ufrgs.br
Charles Bonatto
Affiliation:
Departamento de Astronomia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil email: balbinot@if.ufrgs.br
Corresponding
E-mail address:
Rights & Permissions[Opens in a new window]

Abstract

We present photometry for the globular cluster NGC 6642 using the F606W and F814W filters with the ACS/WFC third-generation camera aboard the Hubble Space Telescope. The colour–magnitude diagram shows sources reaching ≈ 6 mag below the turnoff in mF606W. Theoretical isochrone fitting was performed and evolutionary parameters were obtained, including the metallicity [Fe/H] = −1.80 ± 0.2 dex and age, log(age/yr) = 10.14 ± 0.05. We confirm that NGC 6642 is located in the Galactic bulge, at a distance of d = 8.05±0.66 kpc and suffers from a reddening of E(BV) = 0.46 ± 0.02 mag. These values are in general agreement with those of previous authors. Completeness-corrected luminosity and mass functions were obtained for different annuli centred on NGC 6642. Their spatial variation indicates the existence of mass segregation and depletion of low-mass stars. Most striking is the inverted shape of the mass function itself, with an increase in stellar numbers as a function of increasing mass. This has been observed previously in other globular clusters and is also the result of N-body simulations of stellar systems which have reached ≃90% of their lifetime and are subjected to strong tidal effects. We thus conclude that NGC 6642 is a very old, highly evolved globular cluster. Its current location close to perigalacticon, at only 1.4 kpc from the Galactic Centre, may contribute to this high level of dynamical evolution and stellar depletion.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2010

References

Aguilar, L., Hut, P., & Ostriker, J. 1988, ApJ, 335, 720CrossRefGoogle Scholar
Balbinot, E., Santiago, B., Bica, E., & Bonatto, C. 2009, MNRAS, 396, 1596CrossRefGoogle Scholar
Baumgardt, H. & Makino, J. 2003, MNRAS, 340, 227CrossRefGoogle Scholar
De Marchi, G. & Pulone, L. 2007, A&A, 467, 107Google Scholar
Dolphin, A. E. 2000, PASP, 112, 1383CrossRefGoogle Scholar
Girardi, L., Bressan, A., Bertelli, G., & Chiosi, C. 2000, A&AS, 141, 371Google Scholar
Marks, M., Kroupa, P., & Baumgardt, H. 2008, MNRAS, 386, 2047CrossRefGoogle Scholar
Paust, N., et al. 2009, AJ, 137, 246.CrossRefGoogle Scholar
Origlia, L., Valenti, E., Rich, R., & Ferraro, F. 2005, MNRAS, 363, 897CrossRefGoogle Scholar
Richer, H., et al. 2008, AJ, 135, 2141CrossRefGoogle Scholar
Sarajedini, A., et al. 2007, AJ, 133, 1658CrossRefGoogle Scholar
Shin, J., Kim, S., & Takahashi, K. 2008, MNRAS (Letters), 386, L67CrossRefGoogle Scholar

Full text views

Full text views reflects PDF downloads, PDFs sent to Google Drive, Dropbox and Kindle and HTML full text views.

Total number of HTML views: 0
Total number of PDF views: 19 *
View data table for this chart

* Views captured on Cambridge Core between September 2016 - 6th March 2021. This data will be updated every 24 hours.

Access

Send article to Kindle

To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about sending to your Kindle.

Note you can select to send to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

The globular cluster NGC 6642: evidence for a depleted mass function
Available formats
×

Send article to Dropbox

To send this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Dropbox.

The globular cluster NGC 6642: evidence for a depleted mass function
Available formats
×

Send article to Google Drive

To send this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Google Drive.

The globular cluster NGC 6642: evidence for a depleted mass function
Available formats
×
×

Reply to: Submit a response


Your details


Conflicting interests

Do you have any conflicting interests? *