61. Interstellar Medium And Galactic Turbulence interstellar medium and Galactic Turbulence. Korpi+99a MJ Korpi, A. Brandenburg,A. Shukurov, I. Tuominen, and Å. Nordlund. A Supernova http://www.tac.dk/~aake/bib/ISM.html

Interstellar Medium and Galactic Turbulence Korpi+99a: A Supernova Regulated ISM: Simulations of the Turbulent Multiphase Medium ApJ Nordlund+Padoan98puebla: The Density PDFs of Supersonic Random Flows . In J. Franco and A. Carraminana, editors, Interstellar Turbulence, Proceedings of the 2nd Guillermo Haro Conference , 218. Cambridge University Press, 1999. Padoan+00a: A Comparison of CO Local Thermodynamic Equilibrium and True Column Densities in Molecular Cloud Models ApJ , 529:259267, January 2000. Padoan+01cores: The Turbulent Shock Origin of Proto-Stellar Cores ApJ , 553:227234, May 2001. Padoan+01dust: Theoretical Models of Polarized Dust Emission from Protostellar Cores ApJ , 559:10051018, October 2001. Padoan+01turb: Turbulent Fragmentation and the Initial Conditions for Star Formation ApJ , (submitted), 2001. Padoan+96ext: Supersonic Turbulence in the ISM: stellar extinction determinations as probes of the structure and dynamics of dark clouds ApJ Padoan+96imf: The Universality of the Stellar Initial Mass Function MNRAS Padoan+97cat: Synthetic Molecular Clouds from Supersonic MHD and Non-LTE Radiative Transfer Calculations ApJ Padoan+97co: A Comparison of $^13$CO Local Thermodynamic Equilibrium and True Column Densities in Molecular Cloud Models ApJ Padoan+97eq: Ambipolar Drift Heating in Turbulent Molecular Clouds ApJ Padoan+97perseus: Supersonic Turbulence in the Perseus Moleular Cloud ApJ Padoan+Nordlund01imf: The Stellar IMF from Turbulent Fragmentation ApJ , (submitted), 2000.

62. Chapter 33: The Interstellar Medium Chapter 33 The interstellar medium. Links from Chapter. http://www.williams.edu/Astronomy/jay/chapter33_etu6.html

Chapter 33: The Interstellar Medium Links from Chapter Infrared Space Observatory (ISO) Space Infrared Telescope Facility National Radio Astronomy Observatory Homepage 2MASS Homepage Additional Links 2MASS Homepage at UMass-Amherst Farhad Yusef-Zadeh's combination images; see Orion especially Vinyl Alcohol Discovered in Interstellar Space NRAO Press Release, October 2 Astronomers using the National Science Foundation's 12 Meter Telescope at Kitt Peak, Ariz., have discovered the complex organic molecule vinyl alcohol in an interstellar cloud of dust and gas near the center of the Milky Way Galaxy. The discovery of this long-sought compound could reveal tantalizing clues to the mysterious origin of complex organic molecules in space. "The discovery of vinyl alcohol is significant," said Barry Turner, a scientist at the National Radio Astronomy Observatory (NRAO) in Charlottesville, Va., "because it gives us an important tool for understanding the formation of complex organic compounds in interstellar space. It may also help us better understand how life might arise elsewhere in the Cosmos." Vinyl alcohol is an important intermediary in many organic chemistry reactions on Earth, and the last of the three stable members of the C2H4O group of isomers (molecules with the same atoms, but in different arrangements) to be discovered in interstellar space. Turner and his colleague A. J. Apponi of the University of Arizona's Steward Observatory in Tucson detected the vinyl alcohol in Sagittarius B - a massive molecular cloud located some 26,000 light-years from Earth near the center of our Galaxy. The astronomers were able to detect the specific radio signature of vinyl alcohol during the observational period of May and June of 2001. Their results have been accepted for publication in Astrophysical Journal Letters.

63. Seb Oliver's Interstellar Medium WWW Page (F3052) The interstellar medium Astrophysics 2B, F3052, Summer 2002. Course Documents. Forthis purpose you can access interstellar medium (2001) Lecture Notes. http://astronomy.sussex.ac.uk/~sjo/teach/ism.html

"The Interstellar Medium" Astrophysics 2B, F3052, Summer 2002 Course Documents Links Print formats Course Document PDF Format Course Outline PDF Format Reading List For all my courses including this one Reading List Physical Constants sheet Exam Version Last Year's Notes You might like to bring some notes into the class with you so that you can annotate them. For this purpose you can access Interstellar Medium (2001): Lecture Notes Warning: some of these files are large. Lecture WWW Power Point Power Point Show PDF 1 per page PDF 6 per page last change A Survey HTML MS PowerPoint PDF PDF Atomic levels HTML MS PowerPoint PDF PDF Observations HTML MS PowerPoint PDF PDF Molecular Clouds HTML MS PowerPoint PDF PDF Dust HTML MS PowerPoint PDF PDF HII Regions HTML MS PowerPoint PDF PDF Supernova Remnants HTML MS PowerPoint PDF PDF Magnetic Fields HTML MS PowerPoint PDF PDF Cosmic Rays HTML MS PowerPoint PDF PDF The Living ISM HTML MS PowerPoint PDF PDF Miscellaneous Figures PDF Problem Sheets Set Questions Solutions Sheet 1 PDF (acroread) Format PDF Sheet 2 PDF (acroread) Format PDF Sheet 3 PDF (acroread) Format PDF Sheet 4 PDF (acroread) Format PDF Links This section provides some useful WWW sites and while grow with time. I would welcome any comments on these or other sites.

64. Harvard Astronomy 208 Physicalprocesses in the interstellar medium of the Milky Way and other galaxies.......Astronomy 208 The Physics of the interstellar medium. Course http://icg.harvard.edu/4842

65. Douglas McGonagle Ph.D. Thesis Similar pages interstellar medium and Galactic Turbulenceinterstellar medium and Galactic Turbulence. Boldyrev+01a S. Boldyrev, A. Nordlund,and P. Padoan. KolmogorovBurgers Model for Turbulence in Molecular Clouds. http://donald.phast.umass.edu/theses/mcg/thesis.html

Nitrogen Chemistry in the Interstellar Medium by Douglas McGonagle Department of Physics and Astronomy B.A., University of Massachusetts, Amherst Ph.D., University of Massachusetts, Amherst Committee Chair: William Irvine Committee Members: C. Read Predmore F. Peter Schloerb Mark Heyer Charles Dickinson, Outside Member Department Chair: John F. Dubach Abstract We have carried out radio observations for the interstellar molecules NO, NS, and HCCN in order to investigate the role of nitrogen in the chemistry of the interstellar medium (ISM). Abundances of these species and implications for chemistry models are discussed. In addition, we have conducted a spectral line survey towards the star forming region Orion(KL) over the frequency range 160-170 GHz, which revealed a large number of spectral features arising from such nitrogen-bearing molecules as NS, HNCO, HCCCN, CH CN, CH CHCN, and CH CH CN. The first detection of interstellar nitric oxide (NO) in the cold dark cloud L134N is reported, and we also confirm the subsequent detection towards TMC-1. The inferred NO fractional abundance relative to molecular hydrogen for L134N is f towards the position of peak SO emission in that cloud. The inferred fractional abundance for TMC-1 is f

66. Master Thesis Colloquium, Description Of The Interstellar Medium, The Phases http://www.astro.ku.dk/~boris/talks/speciale/1/index1.html

67. The Interstellar Medium next up previous Next Galactic population Up An overview PreviousOptical and other high. The interstellar medium. Refractive index http://www.jb.man.ac.uk/~pulsar/Education/Tutorial/tut/node14.html

Next: Galactic population Up: An overview Previous: Optical and other high The interstellar medium Refractive index for radio waves Refractive index is frequency dependent Frequency dependant delay in arrival time Dispersion Measure - DM Scattering Scintillation Faraday Rotation Figure 7: Dispersed pulses from the Vela pulsar. The bottom trace shown the profile obtained by dedispersing and summing the other traces. The asymmetric nature of the pulse profile is due to interstellar scattering. Jon Bell Thu Dec 19 15:15:11 GMT 1996

68. The Interstellar Medium next up previous Next Dispersion Up A Tutorial on Radio PreviousAssignment 1. The interstellar medium. Dispersion; Thin screen http://www.jb.man.ac.uk/~pulsar/Education/Tutorial/tut/node24.html

Next: Dispersion Up: A Tutorial on Radio Previous: Assignment 1 The Interstellar medium Dispersion Thin screen scintillation model Diffractive scintillation Refractive scintillation ... Faraday rotation and the Galactic B field Jon Bell Thu Dec 19 15:15:11 GMT 1996

69. Interstellar Medium next up previous contents Old Page interstellar medium. PLANCK will provide allskymaps of the emission from Galactic dust at sub-mm and mm wavelengths. http://astro.estec.esa.nl/Planck/report/redbook/171.htm

Old Page Interstellar Medium PLANCK will provide all-sky maps of the emission from Galactic dust at sub-mm and mm wavelengths. At the two shortest wavelengths the PLANCK maps will have the same resolution as those from IRAS with an order of magnitude better sensitivity in terms of gas column density: N(H) of a few times 10 H cm . At longer wavelengths the detection limit is 1 to H cm . This sensitivity allows the detection of emission from Galactic dust over the whole sky in all of the bolometric bands. One can thus expect that PLANCK will have an even more significant impact on Galactic studies than the successful IRAS mission. Within the Galactic plane the sub-mm data will allow a decomposition of the IR emission from the different gas components and, in particular, the detection of emission from cold clouds that are not heated by active star forming regions. The fraction of gas in such clouds is still a matter of debate, and an estimate of its value is essential in establishing the efficiency of star formation in our Galaxy. The IRAS data have been used to derive the size distribution of interstellar grains ( Desert et al.

70. Star Formation; The Interstellar Medium Star Formation; The interstellar medium. Contents Stellar Nurseries us.We are stardust! The General interstellar medium (ISM). There http://www.astro.queensu.ca/~hanes/p014/Notes/Topic_063.html

Star Formation; The Interstellar Medium Contents: Stellar Nurseries Signposts of Star Formation The Orion Nebula Putting It All Together: The Full Cycle ... Dust in Reflection Nebulae Associated Readings from the Text Please look at: Chapter 16, pages 514-519; Chapter 18, pages 563-578. Stellar Nurseries As we have seen, there are young stars as well as old stars in the heavens. In other words, some stars formed billions of years ago, while others formed very recently. Is it possible to regions in which stars are forming right now? How would we recognize such stellar nurseries? Signposts of Star Formation In seeking to identify stellar nurseries, there are a number of tell-tale things we can look for: O and B stars. These are massive stars which are so hot that they consume their fuel supply very rapidly. Such stars cannot last very long, so if you find a region which contains them, you can be sure that star formation occurred recently there (and may still be going on). HII regions (i.e. ionized gas clouds). O stars, being extremely hot, produce enormous amounts of ultraviolet radiation. Such photons ionize any surrounding gas, converting neutral hydrogen (denoted HI and read as ``H-one'') into ionized gas (HII, ``H-two''). The gas fluoresces, and gives off visible light with the characteristic emission-line pattern of hydrogen gas (and whatever other species are present). The existence of a large HII region is usually a tell-tale sign of the presence of bright, young O stars, recently formed. Dusty, gassy regions.

71. Interstellar Medium, Home interstellar medium. logo, interstellar medium. Welcome to the InterstellarMedium. My hobby is to see the sky and explore what is out there. http://home.attbi.com/~kasism/wsb/html/view.cgi-home.html-.html

Interstellar Medium Highlights Horsehead TEC140 2 60' on LE400 soft seeing using LE400 unhypered IC4592 - 2 12' exposures 8" f/1.5 Schmidt Camera on E200 +1 Stop at New Mexico Skies M1 - ST7e 3x10' 8" f/5.1 Newt Me with the TEC140 at the Tx Astronomical Society of Dallas dark sky site ... Saturn using TEC140 + 4x Powermate on AVA2000 with yellow filter Interstellar Medium Welcome to the Interstellar Medium. My hobby is to see the sky and explore what is out there. I have been 'into' astronomy since 1967 and only work to support it. Join me on a film and digital imaging tour. My current goal is to image from in the light pollution in the DFW megaplex and be able to enjoy the hobby every night. I am learning astrometry and photometry along with pretty pictures. My gear is a AP1200 GTO mount with currently an 8" F/4.5 Cave. Watch for new pictures and gear! You are visitor

72. Absorption Line Spectroscopic Studies Of The Interstellar Medium Absorption Line Spectroscopic Studies of the interstellar medium. Warm(5,00010,000 K) gas in the interstellar medium is seen only http://jilawww.colorado.edu/~jlinsky/abs.html

Absorption Line Spectroscopic Studies of the Interstellar Medium Warm (5,000-10,000 K) gas in the interstellar medium is seen only in isolated clouds that can be identified by their kinematics, temperatures, and metal depletions on to grains. High resolution HST and FUSE spectra covering the 912-3000 A region contain many absorption lines formed in warm clouds. The Sun is located just inside one such cloud, the Local Interstellar Cloud (LIC) , and within 100 pc of the Sun there are other clouds with different kinematic and physical properties. We are building a three-dimensional model of the warm gas clouds within 100 pc of the Sun and developing models for the ionization balance of these clouds. See the Webpage of the Colorado Model of the Local Interstellar Cloud . A view of the LIC looking down from the North Galactic Pole showing that the Sun (located at 0,0) lies barely inside the LIC. Research Objectives: Model the structure and kinematics of warm clouds in the interstellar medium out to about 100 pc. Determine the physical properties (temperature, density, and ionization state) of warm clouds in the local interstellar medium.

73. The Interstellar Medium observations. The interstellar medium. Several groups work on problemsrelated to the interstellar matter and its distribution and physics. http://www.astro.su.se/English/aar9798/node18.html

Next: The molecular medium in Up: RESEARCH Previous: Near infrared variability observations The Interstellar Medium . Other directions covering the star formation regions and molecular clouds in our own Galaxy as well as in other galaxies are presented here. The molecular medium in external galaxies (A. Andersson, H. Olofsson) Interstellar filaments and fragments (G. Gahm, A. Kaas, H. Kristen)

74. Interstellar Medium interstellar medium. Aller, Lawrence Hugh. Dyson, John Edward and Williams,David Arnold. Physics of the interstellar medium. New York Wiley, 1980. http://www.ericweisstein.com/encyclopedias/books/InterstellarMedium.html

Interstellar Medium Aller, Lawrence Hugh. Physics of Thermal Gaseous Nebulae: Physical Processes in Gaseous Nebulae. Dordrecht, Netherlands: D. Reidel, 1988. 350 p. $57. Andrew, Bryan H. (Ed.). Interstellar Molecules: Symposium No. 87, Held at Mont Tremblant, Quebec, Canada, August 6-10, 1979. Dordrecht, Netherlands: Reidel, 1980. 704 p. $76.50. Balian, Roger; Encrenaz, Pierre; and Lequeux, James (Eds.). Atomic and Molecular Physics and the Interstellar Matter: Les Houches, Session XXVI, 1 juillet-23 aout 1974. Amsterdam, Netherlands: North-Holland, 1975. 632 p. Out of print? Bowers, Richard L. and Deeming, Terry. Vol. 2: Interstellar Matter and Galaxies. Boston, MA: Jones and Bartlett Publishers, 1984. Diercksen, G. H. F.; Huebner, Walter F.; and Langhoff, Peter W. (Eds.). Molecular Astrophysics: State of the Art and Future Directions. Dordrecht, Netherlands: Reidel, 1985. 744 p. $143. Dyson, John Edward and Williams, David Arnold. Physics of the Interstellar Medium. New York: Wiley, 1980. 194 p. $130. Franco, J.; Ferrini, F.; Tenorio-Tangle, G.

75. Infrared, Etc There are also neutral gas atoms present which are destroyed close to the Sunbut are replenished from the interstellar medium. interstellar medium. http://www.herts.ac.uk/astro_ub/aI_ub.html

Astronomy KEYWORD DEFINITIONS. - I - Infrared Electromagnetic radiation with a wavelength longer than visible light . The range is approximately between 10 and 10 metres. Infrared radiation is often observed from protostars and other objects which are deeply buried within dense interstellar clouds . Visible light is attenuated by these clouds but they can be penetrated by the longer wavelengths of infrared. Inflation . See inflationary cosmology. Inflationary cosmology . A revision to the standard model of the big bang to include an epoch when the universe was 10 seconds old during which the spacetime continuum expanded faster than the speed of light . As nothing was travelling through the spacetime continuum at a speed greater than that of light, no laws of physics are broken by this theory. The huge inflation of space was driven by the grand unified force separating into two: the strong nuclear force and the electroweak force . Tiny isotropic regions of the early universe were inflated to become larger than the observable universe. This aspect of the theory provides a satisfactory solution to the horizon problem . It also provides an answer to the flatness problem since by inflating the universe so much, any curvature becomes difficult to perceive. Hence as a result, the large scale geometry of the universe appears to be flat. This is in the same way as the surface of the Earth appears to us to be flat, even though we know it is really curved.

76. Shock Effects In The Interstellar Medium Shock effects in the interstellar medium. Other highenergy processeslinked with YSOs may also affect the dense interstellar medium http://www.astro.psu.edu/users/edf/araa/node14.html

77. Interstellar Medium Research At OU CURRENT RESEARCH ON THE interstellar medium. NebularAstrophysics. Last updated 2001 7 July. http://plato.phy.ohiou.edu/~astro/interstellar_medium.html

CURRENT RESEARCH ON THE INTERSTELLAR MEDIUM Nebular Astrophysics Last updated 2001 7 July

78. Interstellar Medium Theory At Wisconsin strong limits on the quantities of various consitituents and rates of various processesthat have been imagined to be occurring in the interstellar medium. http://wisp.physics.wisc.edu/ism/theory/theory.html

Don Cox is the professor around whom the ISM theory effort centers. In recent years he has found himself with so much work left to do with former grad students and so many unfinished projects that he has decided not to have any more new grad students until he gets caught up, maybe never. Since professors can't get anything done by themselves, that means that he hires undergrads as well as attempting to choreograph the efforts of his far flung collection of former students. He presently has one terminal master's student, Mike Walters, who will finish in December 1997, and two undergraduates, Andy Pawl and Angel Klohs, working with him. Current projects include: 1) The development of a fast and reliable approximation for the non- equilibrium cooling rate coefficient for high temperature plasmas, for use in multidimensional hydrocodes which need it desperately. 2) Modeling the formation of a shell of hydrogen around quasars and young galaxies, driven by the readiation pressure of Lyman alpha. 3) A comprehensive model of the supernova remnant W44, including explanations for its unusual centrally brightened x-ray emission, its expanding hydrogen shell, its radio continuum, and its optical luminosity, as well as its nonspherical geometry.

79. 3.2.4 The Molecular Interstellar Medium 3.2.4 The Molecular interstellar medium. The evolution of galaxiesis driven by the cycling of gas among several forms, principally http://www.drao.nrc.ca/science/ska/futures_report/node45.html

Next: Physical and Chemical Structure Up: The Large Southern Array Previous: Outflows from Star-Forming Regions 3.2.4 The Molecular Interstellar Medium The evolution of galaxies is driven by the cycling of gas among several forms, principally diffuse clouds, dense clouds, star-forming cores, and circumstellar envelopes. Since the discovery of interstellar CO twenty-five years ago, we have learned a great deal about the diverse morphology and physical properties of the interstellar gas. However, our understanding of the origins of and the relationships between these various structures remains rudimentary. The physical properties of cold neutral gas are best studied using rotational transitions of molecules. Over a hundred different interstellar and circumstellar molecules have now been identified. Each of these has accessible lines, mostly at millimetre and submillimetre wavelengths. The complex energy structure of molecules makes them ideal diagnostics for gas with densities from 10 to 10 cm and temperatures from 10 to 1000 K. Molecular lines have become a tool for the study of molecular gas rivaling in power the recombination lines used at optical wavelengths since the 1950's and at radio wavelengths since the 1960's to probe the ionized gas. Physical and Chemical Structure of Molecular Clouds Shocks Photon Dominated Regions Diffuse Clouds and Very Cold Gas Thu Apr 10 15:22:13 PDT 1997

80. The Interstellar Medium The interstellar medium. The interstellar medium is the matrix withinwhich the processes of galaxy evolution occur. It exists in http://www.drao.nrc.ca/science/ska/futures_report/node22.html

Next: 3.1.4 Formation and Evolution Up: 3.1.3 Galaxy Evolution and Previous: Radio Continuum Imaging The Interstellar Medium The interstellar medium is the matrix within which the processes of galaxy evolution occur. It exists in many states: atomic and ionized hydrogen, relativistic plasma, molecular gas, and dust, each containing velocity and density structures over a vast range of scales. At the low spatial scales, a highly disturbed state is maintained by point-like energy input from stars at all phases of the stellar lifecycle. On the other end of the scale, energy input can take the form of global, large-scale phenomena, such as viscous dissipation or magnetic stress from Galactic rotation, and the motion of spiral arm density waves. Despite the apparent flux of energy on all scales, pockets of relative quiescence exist, where cold gas can self-gravitate and the process of star formation begins. The life cycle of stars, and the state and evolution of the ISM environment, are intimately intertwined. Previous sections have discussed the imaging power of SKA for atomic hydrogen, relativistic plasma, and ionized medium in galaxies. In the Milky Way the resolving power of the SKA will allow images of these components of the ISM on scales of AU anywhere in the Galaxy, and below an AU within 1 kpc from the Sun. We will be able to study processes in the ISM that require imaging on the scale of stellar dimensions, for example, the final stages of the formation of stars, energy injection from stars into the ISM, shock propagation, and the interface boundaries between ISM states and conditions.

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