Neutral sodium from comet Hale-Bopp: A third type of tail

被引：78

作者：

Cremonese, G

Boehnhardt, H

Crovisier, J

Rauer, H

Fitzsimmons, A

Fulle, M

Licandro, J

Pollacco, D

Tozzi, GP

West, RM

机构：

[1] UNIV MUNICH, D-81679 MUNICH, GERMANY

[2] ESO, SANTIAGO, CHILE

[3] OBSERV PARIS, F-92195 MEUDON, FRANCE

[4] DEUTSCH FORSCH ANSTALT LUFT & RAUMFAHRT, INST PLANETENERKUNDUNG, D-12484 BERLIN, GERMANY

[5] QUEENS UNIV BELFAST, BELFAST BT17 1NN, ANTRIM, NORTH IRELAND

[6] OSSERV ASTRON TRIESTE, I-34131 TRIESTE, ITALY

[7] INST ASTROFIS CANARIAS, E-38200 LA LAGUNA, SPAIN

[8] UNIV REPUBLICA, DEPT ASTRON, MONTEVIDEO, URUGUAY

[9] ISAAC NEWTON GRP, SANTA CRUZ PALMA 38780, SPAIN

[10] OSSERV ASTROFIS ARCETRI, I-50125 FLORENCE, ITALY

[11] ESO, D-85748 GARCHING, GERMANY

来源：

ASTROPHYSICAL JOURNAL | 1997年 / 490卷 / 02期

关键词：

atomic processes; comets; general; individual; (Hale-Bopp; 1995; O1); scattering;

D O I：

10.1086/311040

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We report on the discovery and analysis of a striking neutral sodium gas tail associated with comet C/1995 O1 Hale-Bopp. Sodium D line emission has been observed at heliocentric distance r less than or equal to 1.4 AU in some long-period comets, and the presence of neutral sodium in the tailward direction of a few bright comets has been noted, but the extent, and in particular the source, has never been clear. Here we describe the first observations and analysis of a neutral sodium gas tail in comet Hale-Bopp, which is entirely different from the previously known ion and dust tails. We show that the observed characteristics of this third type of tail are consistent with it being produced by radiation pressure due to resonance fluorescence of sodium atoms and that the lifetime for photoionization is consistent with recent theoretical calculations.

引用

页码：L199 / +

共 22 条

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