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Published on: February 12, 2013
A Spectroscopic Redshift for the Cl 0024+16 Multiple Arc System: Implications for the Central Mass Distribution
The Astrophysical Journal
|May 2, 2000
Summary
We determined a spectroscopic redshift of z=1.675 for arcs in the Cl 0024+16 galaxy cluster. The mass distribution traces bright galaxies, indicating stable cluster potentials and shallow mass profiles consistent with simulations.
Area of Science:
- Cosmology
- Astrophysics
- Galaxy Clusters
Background:
- Galaxy clusters are crucial for understanding large-scale structure formation.
- Gravitational lensing by galaxy clusters provides a unique tool to probe mass distribution.
- Previous studies on Cl 0024+16 have yielded varying interpretations of its mass structure.
Purpose of the Study:
- To determine the spectroscopic redshift of the multiply lensed arcs in the Cl 0024+16 cluster.
- To analyze the projected mass distribution and its relation to the luminous galaxies within the cluster.
- To calculate the cluster's mass and mass-to-light ratio.
Main Methods:
- Spectroscopic observation to obtain redshift.
- Gravitational lensing analysis using a projected mass distribution model.
- Comparison of mass profile with numerical simulations.
- Spectral analysis of arc light.
Main Results:
- A spectroscopic redshift of z=1.675 was found for the lensed arcs.
- The projected mass distribution aligns with the brightest cluster elliptical galaxies.
- The averaged mass profile is shallow and consistent with numerical simulations.
- An enclosed cluster mass of 1.11±0.03x10^14 h^-1 M☉ and a mass-to-light ratio of 320±30 h M☉/L_B were calculated.
- A new pair of multiple images of a galaxy at z=1.3 was identified.
Conclusions:
- The gravitational potential minima in Cl 0024+16 are not dynamically erased.
- The cluster's mass profile supports predictions from recent numerical simulations.
- The lensed arc spectrum resembles that of a local Wolf-Rayet galaxy, suggesting similar properties.
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