NOAO > Observing Info > Approved Programs > 2011B-0353
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NOAO > Observing Info > Approved Programs > 2011B-0353 |
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PI: Rodrigo Carrasco, Gemini Observatory - South, rcarrasco@gemini.edu
Address: Gemini Observatory, Colina El Pino s/n, La Serena, Chile
CoI: Brenda Frye, University of San Francisco
CoI: Dan Coe, Space Telescope Science Institute
CoI: Renato Dupke, Observatorio Nacional (ON/MCT)
CoI: Julian Merten, University of Heidelberg
CoI: Laerte Sodre, Universidade de Sao Paulo
CoI: Richard Massey, University of Edinburgh
CoI: Filberto Braglia, University of British Columbia
CoI: Eduardo Cypriano, Universidade de Sao Paulo
CoI: Adi Zitrin, Tel Aviv University, Israel
CoI: Jessica Krick, Spitzer Science Center, USA
CoI: Narciso Benitez, Instituto de Astrofisica de Andalucia (CSIC), Spain
Title: Constraining the Mass of the Spectacular Pandora's Cluster, Abell 2744
Abstract:
Violent cluster mergers provide a unique opportunity to study the interplay
between dark matter (DM) and ICM and to set constraints on the nature of DM.
In particular, cluster mergers near first core passage allow us to ``see'' DM
by comparing the spatial distribution of the intra-cluster gas (baryonic) to
that of DM. We have recently finished a lensing analysis of the particularly
interesting merging system, A2744, the Pandora cluster. We found that it is
the result of a spectacular merging event, significantly more complex than
the "Bullet Cluster", that produced a wide variety of new phenomenologies,
among them, a Bullet, a Dark sub-cluster (no gas), a Ghost sub-cluster (no
DM), which can provide fundamental insights to the physics of the ICM, and
begs further observations. Our analyses revealed 34 arcs produced by strong
gravitational lensing, none of which had been published to date.
Spectroscopic redshifts of these arcs are essential to determine precise
masses of the main merging system providing crucial information for further
numerical simulations and to set stronger constraints on the DM
self-interaction cross-section. Therefore we are requesting 17.2 hours on
Gemini+GMOS-S, primarily to obtain spectroscopic redshifts of multiply
strongly lensed arcs produced by this impressive cluster.
National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360
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NOAO > Observing Info > Approved Programs > 2011B-0353 |
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