Results 71 to 80 of about 36,750 (220)

Interstellar Abundances in the Magellanic Clouds [PDF]

Symposium - International Astronomical Union, 1999
We discuss the relative gas-phase abundances found for the predominantly neutral interstellar clouds — located in the Galactic disk and halo, in the LMC or SMC, and (perhaps) in between — along the lines of sight to Sk 108 in the SMC and to SN 1987A in the LMC.
D. E. Welty, P. C. Frisch, L. M. Hobbs, D. G. York, J. C. Blades, J. T. Lauroesch, G. Sonneborn   +6 more
openaire   +1 more source

The Boundary Conditions of the Heliosphere: Photoionization Models Constrained by Interstellar and In Situ Data

, 2007
The boundary conditions of the heliosphere are set by the ionization, density and composition of inflowing interstellar matter. Constraining the properties of the Local Interstellar Cloud (LIC) at the heliosphere requires radiative transfer ionization ...
Adams, Ajello, Altobelli, Altun, Anders, André, Bellm, Bertaux, Bloch, Bzowski, Bzowski, Cartledge, Cheng, Cowie, Cravens, Cummings, de Avillez, Dupuis, Ebel, Egger, Ferland, Field, Frisch, Frisch, Frisch, Frisch, Frisch, Frisch, Gloeckler, Gondhalekar, Grevesse, Gry, Gurnett, Henry, Holberg, Holweger, Hébrard, Izmodenov, J. D. Slavin, Juett, Kimura, Koutroumpa, Kruk, Lallement, Lallement, Lallement, Lallement, Lallement, Landgraf, Landsman, Lehner, Linsky, Lodders, Marschall, McCammon, McCammon, McClintock, McClintock, Meyer, Mitchell, Möbius, Müller, Oliveira, P. C. Frisch, Parravano, Pryor, Quémerais, Quémerais, Raymond, Redfield, Redfield, Richardson, Richardson, Ripken, Robertson, Rucinski, Sanders, Savage, Sembach, Simpson, Slavin, Slavin, Slavin, Smith, Snowden, Snowden, Snowden, Snowden, Snowden, Sofia, Stokes, Takei, Thomas, Vallerga, Vallerga, Wargelin, Weller, Welty, Witte, Witte, Wood, Wood, Wood, Wood, York, York   +105 more
core   +3 more sources

The X-ray Iron Emission from Tycho's Supernova Remnant [PDF]

, 1997
We present the results of broadband fits to the X-ray spectrum of Tycho's supernova remnant obtained by the Solid-State Imaging Spectrometers on the ASCA Observatory.
Albinson J. S., Braun R., Fink H. H., Green D. A., John P. Hughes, Mewe R., Reynolds S. R., Robert Petre, Una Hwang   +8 more
core   +2 more sources

Valence Threshold Photoionization Spectra of C5$_5$H and C5$_5$H2$_2$ Isomers

ChemPhysChem, Volume 27, Issue 8, 28 April 2026.
Mass‐selected threshold photoelectron spectra (TPES) of l‐C5H, HC5H, and c–C3H‐CCH were recorded using double‐imaging photoelectron‐photoion coincidence spectroscopy. These transient species were generated in situ by hydrogen abstraction from cyclopropylacetylene and 1,3‐pentadiyne.
Ugo Jacovella, Myriam Drissi, Bérenger Gans, Corentin Rossi, Gustavo A. Garcia, Hai Linh Le, Mengxu Jiang, Jean‐Claude Guillemin, Séverine Boyé‐Péronne, Jean‐Christophe Loison   +9 more
wiley   +1 more source

Prebiotic Organic Chemistry of Diketopiperazines

Asian Journal of Organic Chemistry, Volume 15, Issue 4, April 2026.
Diketopiperazines (DKPs) are considered essential in many life forms, but their prebiotic importance has not been fully understood. This review aims to discuss prebiotic organic chemistry for experimentally and computationally simulated reactions involving DKPs. ABSTRACT Even though the significance of amino acids and polypeptides is well recognized in
Jun Ohata
wiley   +1 more source

Detection of Deuterated Hydrocarbon Nanoparticles in the Whirlpool Galaxy, M51

The Astrophysical Journal Letters
Deuteration of hydrocarbon material, including polycyclic aromatic hydrocarbons (PAHs), has been proposed to account for the low gas-phase abundances of D in the interstellar medium (ISM). JWST spectra of four star-forming regions in M51 show an emission
B. T. Draine, Karin Sandstrom, Daniel A. Dale, J.-D. T. Smith, Ryan Chown, Grant P. Donnelly, Sara E. Duval, Cory M. Whitcomb, Angela Adamo, L. Armus, Danielle A. Berg, Torsten Böker, Alberto D. Bolatto, Martha L. Boyer, Daniela Calzetti, B. G. Elmegreen, Brandt A. L. Gaches, Karl D. Gordon, L. K. Hunt, R. C. Kennicutt, Ralf S. Klessen, Thomas S.-Y. Lai, Adam K. Leroy, Sean T. Linden, Alex Pedrini, Noah S. J. Rogers, Julia C. Roman-Duval, Eva Schinnerer, Evan B. Skillman, Fabian Walter, Tony D. Weinbeck, Benjamin F. Williams   +31 more
doaj   +1 more source

Ice Age: Chemodynamical Modeling of Cha-MMS1 to Predict New Solid-phase Species for Detection with JWST

The Astrophysical Journal, 2022
Chemical models and experiments indicate that interstellar dust grains and their ice mantles play an important role in the production of complex organic molecules (COMs).
Miwha Jin, Ka Ho Lam, Melissa K. McClure, Jeroen Terwisscha van Scheltinga, Zhi-Yun Li, Adwin Boogert, Eric Herbst, Shane W. Davis, Robin T. Garrod   +8 more
doaj   +1 more source

The abundance of interstellar lithium

The Astrophysical Journal, 1984
The interstellar Li I 6707-A absorption line is detected toward Rho Oph A at an equivalent width of 3.1 + or - 1.9 (3 sigma)mA. Upper limits near 1 mA also are found toward seven other stars, including 55 Cyg, toward which relatively strong Li I absorption was previously reported.
openaire   +1 more source

The C(3P) + NH3 reaction in interstellar chemistry: II. Low temperature rate constants and modeling of NH, NH2 and NH3 abundances in dense interstellar clouds

, 2015
A continuous supersonic flow reactor has been used to measure rate constants for the C + NH3 reaction over the temperature range 50 to 296 K. C atoms were created by the pulsed laser photolysis of CBr4.
Bourgalais, Jérémy, Capron, Michael, Goulay, Fabien, Hickson, Kevin M., Loison, Jean-Christophe, Picard, Sebastien D. Le, Wakelam, Valentine   +6 more
core   +3 more sources

The Local Bubble and Interstellar Material Near the Sun [PDF]

, 2007
The properties of interstellar matter (ISM) at the Sun are regulated by our location with respect to the Local Bubble (LB) void in the ISM. The LB is bounded by associations of massive stars and fossil supernovae that have disrupted natal ISM and driven ...
A.N. Cox, B.E. Wood, C. Heiles, C. Heiles, C. Heiles, D. Breitschwerdt, D.M. Sfeir, E.C. Bellm, E.J. Geus de, E.M. Berkhuijsen, F. Paresce, I.P. Robertson, J. Maíz-Apellániz, J. Tinbergen, J.-L. Vergely, J.L. Leroy, L. Spitzer, M. Haverkorn, M. Juda, M.A.C. Perryman, M.P. Fitzgerald, P. C. Frisch, P. Frick, P.B. Lucke, P.C. Frisch, P.C. Frisch, P.C. Frisch, P.C. Frisch, P.C. Frisch, P.C. Frisch, P.M. Gondhalekar, P.T. Zeeuw de, R. Lallement, R.C. Bohlin, R.J. Egger, R.J. Rand, R.S. Warwick, S.L. Snowden, T.M. Dame   +38 more
core   +5 more sources