UBVRI Polarimetry of Nova Sgr 2015#2
ATel #7310; S. Muneer, G. C. Anupama, A. V. Raveendran (Indian Institute of Astrophysics, Bengaluru, India), A. Muniyandi, R. Baskar (Vainu Bappu Observatory, IIA, Kavalur, India)
on 30 Mar 2015; 07:41 UT
Credential Certification: G.C. Anupama (gca@iiap.res.in)
We report here the first polarimetric observations of Nova Sgr 2015#2 (PNV J18365700-2855420). The linear polarization observations of the nova in UBVRI spectral bands were obtained during 16-22 March 2015 with a two beam, multichannel polarimeter attached to the 1-m Carl-Zeiss telescope at the Vainu Bappu Observatory, Kavalur, India. The UBV passbands approximate those of Johnson's UBV system and the RI passbands approximate that of Kron-Cousins system. The measured polarizations are listed below. The probable error of measurements are given in the parentheses.
March 16; JD 2457098.50
U: P(%) = 0.23 (0.02), PA (deg) = 140 (3)
B: P(%) = 0.39 (0.02), PA (deg) = 150 (1)
V: P(%) = 0.20 (0.01), PA (deg) = 148 (2)
R: P(%) = 0.19 (0.01), PA (deg) = 145 (1)
I: P(%) = 0.17 (0.02), PA (deg) = 133 (3)
March 17; JD 2457099.48
U: P(%) = 0.15 (0.02), PA (deg) = 22 (3)
B: P(%) = 0.31 (0.02), PA (deg) = 22 (2)
V: P(%) = 0.34 (0.01), PA (deg) = 22 (1)
R: P(%) = 0.21 (0.01), PA (deg) = 15 (1)
I: P(%) = 0.17 (0.01), PA (deg) = 27 (2)
March 18; JD 2457100.46
U: P(%) = 0.15 (0.03), PA (deg) = 176 (6)
B: P(%) = 0.09 (0.02), PA (deg) = 137 (5)
V: P(%) = 0.12 (0.01), PA (deg) = 9 (2)
R: P(%) = 0.12 (0.07), PA (deg) = 156 (16)
I: P(%) = 0.10 (0.01), PA (deg) = 4 (3)
March 19; JD 2457101.47
U: P(%) = 0.20 (0.03), PA (deg) = 128 (4)
B: P(%) = 0.11 (0.02), PA (deg) = 116 (7)
V: P(%) = 0.05 (0.01), PA (deg) = 70 (6)
R: P(%) = 0.06 (0.02), PA (deg) = 110 (9)
I: P(%) = 0.04 (0.02), PA (deg) = 72 (12)
March 20; JD 2457102.45
U: P(%) = 0.24 (0.03), PA (deg) = 165 (3)
B: P(%) = 0.23 (0.02), PA (deg) = 166 (2)
V: P(%) = 0.14 (0.01), PA (deg) = 168 (2)
R: P(%) = 0.06 (0.01), PA (deg) = 1 (6)
I: P(%) = 0.03 (0.02), PA (deg) = 86 (16)
March 21; JD 2457103.44
U: P(%) = 0.25 (0.06), PA (deg) = 140 (7)
B: P(%) = 0.30 (0.02), PA (deg) = 162 (2)
V: P(%) = 0.15 (0.01), PA (deg) = 164 (1)
R: P(%) = 0.07 (0.01), PA (deg) = 152 (4)
I: P(%) = 0.11 (0.02), PA (deg) = 157 (4)
March 22; JD 2457104.48
U: P(%) = 0.14 (0.08), PA (deg) = 168 (16)
B: P(%) = 0.34 (0.03), PA (deg) = 164 (3)
V: P(%) = 0.17 (0.01), PA (deg) = 161 (2)
R: P(%) = 0.11 (0.01), PA (deg) = 161 (2)
I: P(%) = 0.14 (0.01), PA (deg) = 170 (2)
The above listed values are not corrected for the interstellar polarization. Variation is detected in the polarization value as well as the position angle, indicating changes in the effective geometry over time-scales of <1 day.
