Imaging polarimetry of comets C/2013 V1 (Boattini) and 290P/Jager before and after perihelion

TL;DR

This study uses optical polarimetry to analyze the dust properties and physical evolution of comets C/2013 V1 (Boattini) and 290P/Jager before and after perihelion, revealing changes in polarization and brightness profiles.

Contribution

It provides new polarimetric observations at low phase angles for these comets, highlighting dust property variations and physical evolution during perihelion passage.

Findings

Polarization varies from negative to positive between 13° and 27° phase angles.

Aperture polarization values are consistent with other comets.

Brightness profiles show deviations from standard behavior, indicating physical changes.

Abstract

We report the results obtained from the optical polarimetric study of the light scattered by comets C/2013 V1 (Boattini) and 290P/Jager at lower phase angles. The polarimetric observations of two comets have been performed with the 1.04-m Sampurnanand telescope of Aryabhatta Research Institute of observational sciencES near Nainital in India on 2013 December 4 and 5 and on 2014 April 24 using R photometric band ($\lambda$ = 630 nm, $\Delta$$\lambda$ =120nm). We covered observations in both the pre and post perihelion passage of comets C/2013 V1 (Boattini) and 290P/Jager at two phase angles $\sim$ 13$^\circ$ and 27$^\circ$. The degree of polarization changes from ($-1.4$$\pm 0.3$)per cent to (+2.8$\pm 0.5$)per cent for comet C/2013 V1 (Boattini) and ($-1.6$$\pm 0.5$)per cent to (+2.5$\pm 0.5$)per cent for comet 290P/Jager at phase angles $\sim$ 13$^\circ$ and 27$^\circ$ respectively. The change in the physical properties of cometary dust is being well studied from the polarization maps obtained for both the period of observations. It is found that the aperture polarization values are comparable to those of other comets. The variation in the brightness profile of both the comets from the standard canonical nature is also being observed in both the solar and anti-solar direction during this phase which suggests the various physical evolution influencing the cometary comae.