Results 21 to 30 of about 260,636 (325)

Proton Ordering of Cubic Ice Ic: Spectroscopy and Computer Simulations

The Journal of Physical Chemistry C, 2014
Several proton-disordered crystalline ice structures are known to proton order at sufficiently low temperatures, provided that the right preparation procedure is used. For cubic ice, ice Ic, however, no proton ordering has been observed so far. Here, we subject ice Ic to an experimental protocol similar to that used to proton order hexagonal ice.
Geiger P, Dellago C, Macher M, Franchini C, Kresse G, Bernard J, Stern JN, Loerting T   +7 more
openaire   +3 more sources

VLT Spectroscopy of Blue Supergiants in IC 1613 [PDF]

The Astrophysical Journal, 2007
We present multi-object spectroscopy of young, massive stars in the Local Group galaxy IC 1613. We provide the spectral classification and a detailed spectral catalog for 54 OBA stars in this galaxy. The majority of the photometrically selected sample is composed of B- and A-type supergiants. The remaining stars include early O-type dwarfs and the only
Bresolin, Fabio, Urbaneja, Miguel A., Gieren, Wolfgang, Pietrzynski, Grzegorz, Kudritzki, Rolf-Peter   +4 more
openaire   +2 more sources

CO2 Ice toward Low-luminosity, Embedded Protostars: Evidence for Episodic Mass Accretion via Chemical History [PDF]

, 2012
We present Spitzer IRS spectroscopy of CO2 ice bending mode spectra at 15.2 micrometer toward 19 young stellar objects with luminosity lower than 1 Lsun (3 with luminosity lower than 0.1 Lsun). Ice on dust grain surfaces can encode the history of heating
André, Bergin, Chen, Chen, Chiar, Cook, D'Hendecourt, di Francesco, Doty, Dunham, Dunham, Dunham, Dunham, Dunham, Ehrenfreund, Enoch, Enoch, Evans, Furuya, Garrod, Gerakines, Hagen, Hansen, Houck, Hyo Jeong Kim, Ivezic, Jeong-Eun Lee, Kim, Klaus M. Pontoppidan, Knez, Larson, Lee, Lee, Masunaga, Michael M. Dunham, Neal J. Evans, Oba, Offner, Pontoppidan, Pontoppidan, Roser, Visser, Vorobyov, Vorobyov, Whittet, Young, Young, Young, Öberg   +48 more
core   +2 more sources

Accretion and photodesorption of CO ice as a function of the incident angle of deposition [PDF]

, 2019
Non-thermal desorption of inter- and circum-stellar ice mantles on dust grains, in particular ultraviolet photon-induced desorption, has gained importance in recent years.
Aparicio, S., Carrascosa de Lucas, H., Cazaux, S., Chen, Y.-J., González Díaz, C., Hsiao, L.-C., Munoz Caro, G.M., Sie, N.-E.   +7 more
core   +3 more sources

Molecular Structure and Modeling of Water-Air and Ice-Air Interfaces Monitored by Sum-Frequency Generation. [PDF]

, 2020
From a glass of water to glaciers in Antarctica, water-air and ice-air interfaces are abundant on Earth. Molecular-level structure and dynamics at these interfaces are key for understanding many chemical/physical/atmospheric processes including the ...
Backus, Ellen HG, Bonn, Mischa, Imoto, Sho, Mukamel, Shaul, Nagata, Yuki, Ohto, Tatsuhiko, Rouxel, Jérémy R, Sun, Shumei, Tang, Fujie   +8 more
core   +3 more sources

Effects of CO2 on H2O band profiles and band strengths in mixed H2O:CO2 ices [PDF]

, 2006
H2O is the most abundant component of astrophysical ices. In most lines of sight it is not possible to fit both the H2O 3 um stretching, the 6 um bending and the 13 um libration band intensities with a single pure H2O spectrum.
A. C. A. Boogert, Ayers, Bergin, Bernstein, Boogert, Boogert, Collings, Danten, Devlin, E. F. van Dishoeck, Ehrenfreund, G. W. Fuchs, Gerakines, Gerakines, Gerakines, Gibb, Gibb, H. J. Fraser, H. Linnartz, Hagen, Hudgins, K. I. Öberg, Keane, Knez, Murakawa, Nummelin, Palumbo, Pontoppidan, Rowland, S. E. Bisschop, Sandford, Schmitt, Schutte, Tanaka, Tso, van Thiel, Whittet, Willner   +37 more
core   +3 more sources

Brief Communication: Ikaite (CaCO₃·6H₂O) discovered in Arctic sea ice [PDF]

The Cryosphere, 2010
We report for the first time on the discovery of calcium carbonate crystals as ikaite (CaCO3·6H2O) in sea ice from the Arctic (Kongsfjorden, Svalbard) as confirmed by morphology and indirectly by X-ray diffraction as well as XANES spectroscopy of ...
M. A. Granskog, S. Gerland, C. Uhlig, J. Göttlicher, G. Nehrke, G. S. Dieckmann, D. N. Thomas   +6 more
doaj   +1 more source

Distinguishing ice β-XV from deep glassy ice VI: Raman spectroscopy

Physical Chemistry Chemical Physics, 2019
Evidence for the existence of D2O-ice β-XV is given by the observation of its librational Raman band at 380 cm−1.
Alexander V. Thoeny, Tobias M. Gasser, Thomas Loerting   +2 more
openaire   +3 more sources

Investigation of HNCO isomers formation in ice mantles by UV and thermal processing: an experimental approach [PDF]

, 2014
Current gas phase models do not account for the abundances of HNCO isomers detected in various environments, suggesting a formation in icy grain mantles.
Caro, G. M. Muñoz, Cernicharo, J., Giuliano, B. M., Jiménez-Escobar, A., Marcelino, N.   +4 more
core   +1 more source

Ices in the edge-on disk CRBR 2422.8-3423: Spitzer spectroscopy and Monte Carlo radiative transfer modeling [PDF]

, 2004
We present 5.2-37.2 micron spectroscopy of the edge-on circumstellar disk CRBR 2422.8-3423 obtained using the InfraRed Spectrograph (IRS) of the Spitzer Space Telescope.
Adwin C. A. Boogert, Brandner W., Cornelis P. Dullemond, Dullemond C. P., Dutrey A., Ehrenfreund P., Ehrenfreund P., Ehrenfreund P., Ehrenfreund P., Ewine F. van Dishoeck, Fred Lahuis, Geoffrey A. Blake, Gerakines P. A., Hagen W., Jacqueline E. Kessler‐Silacci, Jager C., Kerkhof O., Kitta K., Klaus M. Pontoppidan, Leger A., Motte F., Neal J. Evans II, Ossenkopf V., Schutte W. A., Schutte W. A., Siess L., Vandenbussche B., Warren S. G.   +27 more
core   +1 more source