PAOLO: a Polarimeter Add-On for the LRS Optics at a Nasmyth focus of the TNG

TL;DR

PAOLO is a newly developed polarimetric instrument at the TNG telescope that enhances polarization measurements by addressing instrumental polarization effects through specific modeling and calibration.

Contribution

This paper introduces PAOLO, a novel polarimeter add-on for the TNG telescope, including its design, calibration, and initial application examples.

Findings

Instrument successfully measures polarization at the Nasmyth focus.

Calibration procedures effectively remove instrumental polarization.

Early observations demonstrate the instrument's capabilities.

Abstract

We describe a new polarimetric facility available at the Istituto Nazionale di AstroFisica / Telescopio Nazionale Galileo at La Palma, Canary islands. This facility, PAOLO (Polarimetric Add-On for the LRS Optics), is located at a Nasmyth focus of an alt-az telescope and requires a specific modeling in order to remove the time- and pointing position-dependent instrumental polarization. We also describe the opto-mechanical structure of the instrument and its calibration and present early examples of applications.