* Astronomy

Members Login
Username 
 
Password 
    Remember Me  
Post Info TOPIC: VVV CL001


L

Posts: 131433
Date:
VVV CL001
Permalink  
 


VISTA Finds New Globular Star Clusters

eso1141a.jpg

Two newly discovered globular clusters have been added to the total of just 158 known globular clusters in our Milky Way. They were found in new images from ESOs VISTA survey telescope as part of the Via Lactea (VVV) survey. This survey has also turned up the first star cluster that is far beyond the centre of the Milky Way and whose light has had to travel right through the dust and gas in the heart of our galaxy to get to us.
The dazzling globular cluster called UKS 1 dominates the right-hand side of the first of the new infrared images from ESO's VISTA survey telescope at the Paranal Observatory in Chile. But if you can drag your gaze away, there is a surprise lurking in this very rich star field - a fainter globular cluster that was discovered in the data from one of VISTA's surveys. You will have to look closely to see the other star cluster, which is called VVV CL001: it is a small collection of stars in the left half of the image.

Read more 



__________________


L

Posts: 131433
Date:
Permalink  
 

Title: Discovery of VVV CL001. A Low-Mass Globular Cluster Next to UKS~1 in the Direction of the Galactic Bulge
Authors: D. Minniti, M. Hempel, I. Toledo, V.D. Ivanov, J. Alonso-García, R. Saito, M. Catelan, D. Geisler, A. Jordán, J. Borissova, M. Zoccali, R. Kurtev, G. Carraro, B. Barbuy, J. Clariá, M. Rejkuba, J. Emerson, C. Moni Bidin

Context: It is not known how many globular clusters may have been left undetected towards the Galactic bulge.
Aims: One of the aims of the VISTA Variables in the Via Lactea (VVV) Survey is to accurately measure the physical parameters of the known globular clusters in the inner regions of the Milky Way and to search for new ones, hidden in regions of large extinction.
Methods: Deep near infrared images give deep JHKs-band photometry of a region surrounding the known globular cluster UKS 1 and reveal a new low-mass globular cluster candidate that we name VVV CL001.
Results: We use the horizontal branch red clump in order to measure E(B-V)~2.2 mag, (m-M)_0=16.01 mag, and D=15.9 kpc for the globular cluster UKS 1. Based on the near-infrared colour magnitude diagrams, we also measure that VVV CL001 has E(B-V)~2.0, and that it is at least as metal-poor as UKS 1, however, its distance remains uncertain. Conclusions: Our finding confirms the previous projection that the central region of the Milky Way harbours more globular clusters. VVV CL001 and UKS 1 are good candidates for a physical cluster binary, but follow-up observations are needed to decide if they are located at the same distance and have similar radial velocities.

Read more (1166kb, PDF)

__________________
Page 1 of 1  sorted by
Quick Reply

Please log in to post quick replies.



Create your own FREE Forum
Report Abuse
Powered by ActiveBoard