Dr. M. Ranganathan Profile

Dr. M. Ranganathan

SPIE Involvement:

Author

Publications (1)

This will count as one of your downloads.

You will have access to both the presentation and article (if available).

DOWNLOAD NOW

This content is available for download via your institution's subscription. To access this item, please sign in to your personal account.

Email or Username Forgot your username?

Password Forgot your password?

Show

Keep me signed in

No SPIE account? Create an account

Proceedings Article | 13 December 2020 Poster + Paper

Polarization model for the multi-application solar telescope at the Udaipur Solar Observatory

Ramya Anche, M. Ranganathan, Shibu Mathew, K. Sankarasubramanian, G. Anupama, Bireddy Ramya, Avijeet Prasad, Rahul Yadav, Raja Bayanna

Proceedings Volume 11451, 114514O (2020) https://doi.org/10.1117/12.2561217

KEYWORDS: Polarization, Telescopes, Mirrors, Observatories, Polarimetry, Magnetism, Solar processes, Reflection, Reflector telescopes, Instrument modeling

Read Abstract +

Solar polarimetry aims at measuring the full set of Stokes vectors (I, Q, U, V) to extract the magnetic field information of the solar atmosphere. During the polarimetric observations, the oblique reflections from the telescope mirrors modify (crosstalk) or even produce polarization (instrumental polarization). For accurate polarimetric measurements of the source, it is important to correctly model and remove the instrumental polarization and crosstalk introduced by the telescope. The Multi-Application Solar Telescope (MAST) at the Udaipur Solar Observatory is a Gregorian-Coude telescope with a 50 cm off-axis parabolic primary mirror. It consists of nine mirrors that rotate as the telescope tracks the object and delivers a constant beam at the observing floor. Here, we present a formalism for an analytical estimation of the telescope's Mueller matrix using a polarization ray tracing algorithm. The model was experimentally verified at 6173 Å using the observations taken from the facility imaging spectro-polarimeter. The observations were split into two sets, during January and May 2018, to verify the model's consistency. The instrumental polarization was found to vary between 1.3% to 5.54%, and 3.5% to 4.3% throughout the observation from 9 AM to 4 PM during summer and winter respectively. The maximum value of the crosstalk (Q to V and U to V) was found to be 29.08% and 39.46% respectively. We obtained a reasonable match between the model and the observations with some offsets. We also discuss the possible reasons for the observed deviations and their effects.

My Library

You currently do not have any folders to save your paper to! Create a new folder below.

Folder Name

Folder Description

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks. You are receiving this notice because your organization may not have SPIE eBooks access.*

*Shibboleth/Open Athens users─please sign in to access your institution's subscriptions.

To obtain this item, you may purchase the complete book in print or electronic format on SPIE.org.

ORGANIZATIONAL
Sign in with credentials provided by your organization.

Organizational Username

Organizational Password

Show/Hide Password

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members:

Non-members: ADD TO CART

Keywords/Phrases

Search In:

Publication Years