J/A+A/384/504 Broadband polarimetry of novae in outburst (Evans+, 2002)
Broadband polarimetry of novae in outburst.
Evans A., Yudin R.V., Naylor T., Ringwald F.A., Koch Miramond L.
<Astron. Astrophys. 384, 504 (2002)>
=2002A&A...384..504E 2002A&A...384..504E
ADC_Keywords: Novae ; Binaries, cataclysmic ; Polarization
Keywords: polarization - stars: circumstellar matter -
stars: novae, cataclysmic variables
Abstract:
We present broadband optical polarimetry of the classical novae
V705 Cas, V4362 Sgr, V2313 Oph and BY Cir in outburst. The data
indicate that, in all cases, there is an intrinsic component of
polarization and in some cases the variability is very rapid, on a
time-scale ∼1day. In the case of V705 Cas, we suggest that the origin
of the intrinsic component may lie in the clumpiness and/or
inhomogeneities of the ejecta, while electron scattering is the most
likely cause in V2313 Oph. The wavelength-dependence of polarization
in the case of V4362 Sgr suggests scattering by small dust grains,
while polarization in resonance lines is the most probable cause of
the observed polarization in BY Cir.
Objects:
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RA (2000) DE Designation(s)
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14 44 53.6 -63 53 56 BY Cir
17 35 44.6 -19 19 34 V2313 Oph
18 30 22.0 -17 12 06 V4362 Sgr
23 41 47.3 +57 31 00 V705 Cas
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 83 65 Polarimetric data for novae
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 10 A10 -- Name Name of source (1)
12- 21 F10.2 d JD JD of mid-observation
23- 27 F5.1 d Time Time since outburst (-9.99 = field star)
29- 32 A4 -- Site Observatory name (2)
34 A1 -- Filter [UVBRIC] Filters. RI = Cousins
36- 40 F5.2 mag Vmag ?=-9.99 V magnitude estimate
(-9.99 = other filters)
42- 46 F5.2 % q Stokes normalized Q parameter
48- 51 F4.2 % e_q 1sigma error in Q
53- 57 F5.2 % u Stokes normalized U parameter
59- 62 F4.2 % e_u 1sigma error in U
64- 67 F4.2 % P Polarization
69- 72 F4.2 % e_P 1sigma error in Polarization
74- 78 F5.1 deg Theta Position angle
80- 83 F4.1 deg e_Theta 1sigma error in Position angle
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Note (1): A number of field stars were also observed; they are designated as
Sgr star a, Sgr star b and Sgr star c for V4362 Sgr field stars,
Cas star b and Cas star e for V705 Cas field stars,
Cir star a, Cir star c and Cir star d for BY Cir field stars, and
Oph star a for V2313 Oph field star.
The finding charts are in the paper.
Note (2): Sites:
SAAO: Observations at South African Astronomical Observatories were
carried out during 1994 August 2-15 and 1995 January 23-February 6.
The University of Cape Town (UCT) photometer-polarimeter module
was used on the SAAO 0.75m telescope, although the observations
for the period 1994 August 9-15 were carried out on the
SAAO 1m telescope.
PdM: observations at the Pic du Midi were carried out with the
Sterenn polarimeter at the Cassegrain focus of the 2m
Bernard Lyot telescope during the period 1994 July 2-July 15.
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Acknowledgements: Aneurin Evans
(End) Patricia Bauer [CDS] 05-Mar-2002