To access this work you must either be on the Smith College campus OR have valid Smith login credentials.

On Campus users: To access this work if you are on campus please Select the Download button.

Off Campus users: To access this work from off campus, please select the Off-Campus button and enter your Smith username and password when prompted.

Non-Smith users: You may request this item through Interlibrary Loan at your own library.

Publication Date

2022-05-07

First Advisor

James Lowenthal

Document Type

Honors Project

Degree Name

Bachelor of Arts

Department

Astronomy

Keywords

astronomy, astrophysics, galaxies, extragalactic, observational astronomy, submillimeter galaxies, galaxy formation and evolution, gravitational lensing, lensing environments, dusty star forming galaxies, starburst galaxies, lens modeling

Abstract

Galaxy evolution approximately 10 billion years ago coincides with peak star formation rates throughout all time and studying these galaxies can improve our understanding of galaxy evolution as a whole. However, at 10 billion light years away, most types of galaxies – especially those with strong dust obscuration – can be faint and difficult to detect and study in detail at optical wavelengths. Our sample consists of approximately 20 dusty star-forming galaxies discovered due to their extreme brightness at submillimeter wavelengths by the Planck satellite, all of which are strongly gravitationally lensed, magnifying their brightness, yet also distorting their shape. We have undertaken a study of J132217, a single field from the larger sample, in which a background starburst galaxy is being lensed by a foreground galaxy group. To reconstruct the true shape of the background source we use LENSTOOL to model the foreground cluster by providing input parameters such as the redshifts of both the source galaxy and foreground cluster, and approximate positions in our images for each of these objects. LENSTOOL uses these input parameters and the Monte Carlo Markov Chain method to iterate through many possible models and attempt to converge on a most likely lens model. We will present our current model of J132217 that uses combined Navarro-Frenk-White and Singular Isothermal Sphere models for the dark matter halos of the foreground lensing galaxies, and discuss the challenges we face in making further improvements.

Rights

©2022 Lilah Mercadante. Access limited to the Smith College community and other researchers while on campus. Smith College community members also may access from off-campus using a Smith College log-in. Other off-campus researchers may request a copy through Interlibrary Loan for personal use.

Language

English

Download

Smith Only:
Off Campus Download

Share

COinS