Results 41 to 50 of about 42,848 (232)

Chemistry in a protoplanetary nebula [PDF]

Monthly Notices of the Royal Astronomical Society, 1992
The gas-phase chemistry in the remnant superwind of a carbon-rich red giant star, during its transition to a planetary nebula, is investigated. The interacting stellar winds model is used. It is found that during the first few hundred years of transition, significant abundances of a few small molecules and ions (e.g. CH + , CH + 2 , CH + 3 , CH, CH 2
Howe, D.A., Millar, TJ, Williams, D.A.
openaire   +1 more source

Fast outflows in protoplanetary nebulae and young planetary nebulae observed by Herschel/HIFI [PDF]

Astronomy & Astrophysics, 2021
Context. Fast outflows and their interaction with slow shells (generally known as the fossil circumstellar envelope of asymptotic giant branch stars) play an important role in the structure and kinematics of protoplanetary and planetary nebulae (pPNe, PNe).
Lorenzo, M., Teyssier, R., Bujarrabal, V., García Lario, P., Alcolea, J., Verdugo, E., Marston, A.   +6 more
openaire   +3 more sources

The chemistry of protoplanetary nebulae [PDF]

Astronomy & Astrophysics, 2003
We describe the chemistry occurring in a dense slab of outwardly expanding gas in the post-AGB phase of stellar evolution. Despite the high flux of UV photons from the central star, the intrinsic dust extinction in the slab prevents rapid photodissociation and allows chemical reactions to make a variety of gas-phase species, some complex.
Woods, P.M., Millar, TJ, Herbst, E., Zijlstra, A.A.   +3 more
openaire   +1 more source

High-resolution optical spectroscopy of the F supergiant protoplanetary nebula IRAS 18095+2704 [PDF]

, 2010
An abundance analysis is presented for IRAS 18095+2704 (V887 Her), a post-asymptotic giant branch star and protoplanetary nebula. The analysis is based on high-resolution optical spectra from the McDonald Observatory and the Special Astrophysical ...
T. Şahìn, David L. Lambert, В. Г. Клочкова, N. S. Tavolganskaya   +3 more
openalex   +3 more sources

Herschel/HIFI observations of molecular emission in protoplanetary nebulae and young planetary nebulae [PDF]

Astronomy & Astrophysics, 2011
We performed Herschel/HIFI observations of intermediate-excitation molecular lines in the far-infrared/submillimeter range in a sample of ten protoplanetary nebulae and young planetary nebulae. The high spectral resolution provided by HIFI yields accurate measurements of the line profiles.
Bujarrabal, V., Alcolea, J., Soria-Ruiz, R., Planesas, P., Teyssier, D., Cernicharo, J., Decin, L., Dominik, C., Justtanont, K., de Koter, A., Marston, A.P., Melnick, G., Menten, K.M., Neufeld, D.A., Olofsson, H., Schmidt, M., Schöier, F.L., Szczerba, R., Waters, L.B.F.M.   +18 more
openaire   +4 more sources

The role of the initial surface density profiles of the disc on giant planet formation: comparing with observations [PDF]

, 2011
In order to explain the main characteristics of the observed population of extrasolar planets and the giant planets in the Solar System, we need to get a clear understanding of which are the initial conditions that allowed their formation. To this end we
A. Brunini, Alexander, Alexander, Andrews, Benvenuto, Bodenheimer, Chambers, Clarke, Edgeworth, Fortier, Fortier, Goldreich, Guilera, Haisch, Hartmann, Hayashi, Hillenbrand, Hollenbach, Ida, Ida, Ikoma, Isella, Kokubo, Kuiper, Lammer, Lin, Lin, Lodders, Lynden-Bell, Lyra, Masset, Matsumura, Menou, Miguel, Miguel, Miguel, Mizuno, Mizuno, Mordasini, Nelson, O. M. Guilera, Paardekooper, Safronov, Stevenson, Tanaka, Terquem, Thommes, Toomre, Triaud, Vinkovic, Weidenschilling, Y. Miguel   +51 more
core   +4 more sources

The composition of the protosolar disk and the formation conditions for comets [PDF]

, 2015
Conditions in the protosolar nebula have left their mark in the composition of cometary volatiles, thought to be some of the most pristine material in the solar system.
A. Dutrey, A. Kouchi, A.E. Glassgold, A.G.G.M. Tielens, A.I. Vasyunin, A.L. Cochran, A.N. Heays, A.Z. Dolginov, B. Silvi, B.P. Bonev, B.P. Bonev, B.P. Bonev, C. Alexander, C. Ceccarelli, C. Ceccarelli, C. Ceccarelli, C. Dominik, C. Qi, C. Qi, C. Qi, C. Qi, C. Salyk, C. Tornow, C. Tornow, C. Tornow, C. Walsh, C. Walsh, C.E. Woodward, C.P. Dullemond, D. Bockelée-Morvan, D. Bockelée-Morvan, D. Bockelée-Morvan, D. Bockelée-Morvan, D. Bockelée-Morvan, D. Gautier, D. Harsono, D. Heinzeller, D. Hutsemékers, D. Kozlowski, D. Semenov, D. Semenov, D.C. Lis, E. Gibb, E. Herbst, E. Jehin, E. Lellouch, E. Roueff, E. S. Wirström, E. Zicler, E.D. Young, E.K. Jessberger, E.L. Gibb, E.S. Wirström, E.S. Wirström, F. Hersant, F. Pauzat, F.C. Adams, F.J. Ciesla, F.J. Ciesla, G. Buntkowsky, G. Bussolin, G. Cremonese, G. Kresse, G. Kresse, G. Notesco, G.J. Flynn, G.J. Villanueva, G.L. Villanueva, G.S. Mathews, H. Kawakita, H. Kawakita, H. Kawakita, H. Kawakita, H. Yurimoto, H. Yurimoto, I. Gregorio-Monsalvo de, I. Pater de, I. Pater de, J. Crovisier, J. Crovisier, J. Crovisier, J. Crovisier, J. Crovisier, J. Schönke, J.-E. Lee, J.C. Mottram, J.E. Heidenreich III, J.F. Hawley, J.F. Hawley, J.I. Lunine, J.J. Kavelaars, J.K.J. Fogel, J.P. Perdew, J.R. Lyons, J.R. Najita, J.S. Carr, J.S. Lewis, J.S. Mathis, K. Altwegg, K. France, K. Hashimoto, K. Nagashima, K. Saigo, K. Willacy, K. Willacy, K. Willacy, K. Willacy, K. Willacy, K. Willacy, K.D. McKeegan, K.I. Öberg, K.M. Chick, K.M. Pontoppidan, K.M. Pontoppidan, K.M. Pontoppidan, K.M. Pontoppidan, K.Y. Furuya, L. Pagani, L. Paganini, L. Podio, L.I. Cleeves, L.I. Cleeves, L.I. Cleeves, L.R. Nittler, M. Ali-Dib, M. Ali-Dib, M. Asplund, M. Calatayud, M. Doronin, M. Hassig, M. Ilgner, M. Ilgner, M. Ilgner, M. Pettini, M.A. DiSanti, M.F. A’Hearn, M.J. Mumma, M.J. Mumma, M.J. Mumma, M.R. Hogerheijde, M.V. Persson, N. Biver, N. Dello Russo, N. Dello Russo, N. Dello Russo, N. Fray, N. Iro, N. Watanabe, N.J. Turner, N.J. Turner, N.J. Turner, O. Mousis, O. Mousis, O. Mousis, O. Mousis, O. Mousis, O. Mousis, O. Mousis, O. Mousis, O. Mousis, O. Mousis, O. Mousis, P. Caselli, P. D’Alessio, P. Eberhardt, P. Eberhardt, P. Gast, P. Hartogh, P. Theulé, P.M. Woods, P.M. Woods, R. Hueso, R. Llusar, R. Meier, R. Meier, R. Visser, R. Visser, R. Visser, R.N. Clayton, R.N. Clayton, S. B. Charnley, S. Casassa, S. Casassa, S. Grimme, S. Gulkis, S. Inutsuka, S. N. Milam, S. Wyckoff, S.A. Balbus, S.B. Charnley, S.B. Charnley, S.B. Charnley, S.B. Charnley, S.B. Charnley, S.D. Rodgers, S.E. Dodson-Robinson, T. Albertsson, T. Albertsson, T. Albertsson, T. Bredichin, T. Hama, T. Lee, T. Owen, T.J. Millar, Th. Henning, U. Marboeuf, U. Marboeuf, U. Marboeuf, V. Akimkin, V. Taquet, V. Taquet, V. Wakelam, V. Zubko, W.-H. Ip, W.D. Langer, W.M. Irvine, Y. Aikawa, Y. Aikawa, Y. Aikawa, Y. Aikawa, Y. Aikawa, Y. Aikawa, Y. Alibert, Y. Alibert, Y. Ellinger, Y. Ellinger, Y. Shinnaka, Y.L. Radeva   +227 more
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On the orbital evolution and growth of protoplanets embedded in a gaseous disc [PDF]

, 1999
We present a new computation of the linear tidal interaction of a protoplanetary core with a thin gaseous disc in which it is fully embedded. For the first time a discussion of the orbital evolution of cores with eccentricity (e) significantly larger ...
Larwood, J. D., Papaloizou, J. C. B.
core   +3 more sources

Accretion of dust by chondrules in a MHD-turbulent solar nebula [PDF]

, 2010
(Abridged) Numerical magnetohydrodynamic (MHD) simulations of a turbulent solar nebula are used to study the growth of dust mantles swept up by chondrules. A small neighborhood of the solar nebula is represented by an orbiting patch of gas at a radius of
Armitage, Augusto Carballido, Balbus, Carballido, Carballido, Ciesla, Ciesla, Cuzzi, Cuzzi, Cuzzi, Cuzzi, Fleming, Fromang, Güttler, Hartmann, Hawley, Krot, Leinhardt, Metzler, Morfill, Ormel, Ormel, Rubin, Shakura, Shu, Stone, Stone, Stone, Trigo-Rodrı´guez, Turner, Turner, Weidenschilling, Zsom, Zsom   +33 more
core   +1 more source

Evolution of protoplanetary nebulae

The Astrophysical Journal, 1989
Model spectra of protoplanetary nebulae have been calculated assuming that mass loss on the asymptotic giant branch terminates when the hydrogen envelope is almost totally depleted. The models predict spectral characteristics of protoplanetary nebulae which can be used to search for new candidates of protoplanetary nebulae in the IRAS Low Resolution ...
Kevin M. Volk, Sun Kwok
openaire   +1 more source