Polarimetric Observations of Comets C/1995 O1 Hale–Bopp and C/1996 B2 Hyakutake

Manset, N.; Bastien, Pierre

doi:10.1006/icar.1999.6315

Cited by 55 publications

(49 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the case of comet Hale Bopp no significant difference was found in the polarization observed through two apertures, 26.5 and 52.4 arcsec, corresponding to linear scales of 14 318 km and 28 313 km respectively (Ganesh et al 1998). Similar results are reported for Hale-Bopp by Manset & Bastien (2000). In the present case the radius of the area sampled on the coma is relatively large (6500 km to 7200 km in diameter, much larger than the inner coma) and the inhomogeneities in the coma are expected to be averaged out.…”

Section: Discussionsupporting

confidence: 77%

Polarization studies of comet C/2000 WM1 (LINEAR)

Joshi

Baliyan

Ganesh

2003

A&A

View full text Add to dashboard Cite

• ) when the polarization is negative and where the data for most of the comets are rather meager. The observations during March were made when the phase angle was ∼47• . Observations were conducted through the IHW narrow band and BVR broad band filters. Based on these polarization observations we infer that the comet C/2000 WM1 belongs to high polarization class i.e. the dusty comet family.

show abstract

Section: Discussionsupporting

confidence: 77%

Polarization studies of comet C/2000 WM1 (LINEAR)

Joshi

Baliyan

Ganesh

2003

A&A

View full text Add to dashboard Cite

show abstract

“…Spatial variations up to 0.1% in the degree of CP were observed. Manset and Bastien (2000) also measured CP in this comet. The absolute value was found at the same level, ≤ 0.3%, both left and right circularly polarized light being detected during April 2-16, 1997.…”

Section: Introductionmentioning

confidence: 67%

“…0 ≈ τ at the distance of about 500 km. Although a non-zero, ≤ 0.3%, circular polarization was measured for the near-nucleus region of comet Hale-Bopp (Rosenbush et al, 1997;Manset and Bastien, 2000) as well as for comet Halley, in both cases the data on circular polarization and optical thicknesses were obtained for different areas of the comae, and this does not allow us to estimate the influence of multiple scattering on formation of the circular polarization. As far as we know, there are no direct measurements of the dust optical thickness for comet S4.…”

Section: Multiple Scatteringmentioning

confidence: 99%

Circular polarization in comets: Observations of Comet C/1999 S4 (LINEAR) and tentative interpretation

Rosenbush

Kolokolova

Lazarian

et al. 2007

Icarus

View full text Add to dashboard Cite

Comet C/1999 S4 (LINEAR) was exceptional in many respects. Its nucleus underwent multiple fragmentations culminating in the complete disruption around July 20, 2000. We present circular polarization measurements along the cuts through the coma and nucleus of the comet during three separate observing runs, in June 28-July 2, July 8-9, and July 21-22, 2000. The circular polarization was detected at a rather high level, up to 0.8%. The left-handed as well as right-handed polarization was observed over the coma with the left circularly polarized light systematically observed in the sunward part of the coma. During our observations the phase angle of the comet varied from 61 up to 122°, which allowed us to reveal variations of circular polarization with the phase angle. Correlation between the degree of circular polarization, visual magnitude, water production rate, and linear polarization of comet C/1999 S4 (LINEAR) during its final fragmentation in July 2000 was found.The mechanisms that may produce circular polarization in comets and specifically in comet C/1999 S4 (LINEAR) are discussed and some tentative interpretation is presented.

show abstract

“…The observed linear polarization data of comet Hyakutake at λ = 0.365µm, 0.485µm & 0.684µm are taken from Joshi et al (1997), Kiselev & Velichko (1998), Manset & Bastien (2000).…”

Section: Numerical Simulationsmentioning

confidence: 99%

Aggregate dust model to study the polarization properties of comet C/1996 B2 Hyakutake

Das

Suklabaidya

Majumder

et al. 2010

Res. Astron. Astrophys.

View full text Add to dashboard Cite

In our present study, the observed linear polarization data of comet Hyakutake are studied at wavelengths λ = 0.365µm, λ = 0.485µm and 0.684µm through simulations using Ballistic Particle-Cluster Aggregate and Ballistic Cluster-Cluster Aggregate aggregates of 128 spherical monomers. We first investigated that the size parameter of the monomer, x ∼ 1.56 -1.70, turned out to be most suitable which provides the best fits to the observed dust scattering properties at three wavelengths λ = 0.365µm, 0.485µm and 0.684µm. Thus the effective radius of the aggregate (r) lies in the range 0.45µm ≤ r ≤ 0.49µm at λ = 0.365µm; 0.60µm ≤ r ≤ 0.66µm at λ = 0.485µm and 0.88µm ≤ r ≤ 0.94µm at λ = 0.684µm. Now using superposition T-MATRIX code and the power-law size distribution, n(r) ∼ r −3 , the best-fitting values of complex refractive indices are calculated which can best fit the observed polarization data at the above three wavelengths. The best-fitting complex refractive indices (n, k) are found to be (1.745, 0.095) at λ = 0.365 µm, (1.743, 0.100) at λ = 0.485 µm and (1.695, 0.100) at λ = 0.684 µm. The refractive indices coming out from the present analysis correspond to mixture of both silicates and organics, which are in good agreement with the in situ measurement of comets by different spacecraft.

show abstract

Polarimetric Observations of Comets C/1995 O1 Hale–Bopp and C/1996 B2 Hyakutake

Cited by 55 publications

References 13 publications

Polarization studies of comet C/2000 WM1 (LINEAR)

Polarization studies of comet C/2000 WM1 (LINEAR)

Circular polarization in comets: Observations of Comet C/1999 S4 (LINEAR) and tentative interpretation

Aggregate dust model to study the polarization properties of comet C/1996 B2 Hyakutake

Contact Info

Product

Resources

About