Download or read book Diffuse Interstellar Bands in Large Spectroscopic Surveys written by Janez Kos and published by . This book was released on 2015 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Diffuse Interstellar Bands IAU S297 written by Jan Cami and published by Cambridge University Press. This book was released on 2014-03-27 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume describes the current state of the art in research aimed at unraveling the carriers of the enigmatic diffuse interstellar bands (DIBs). The DIBs are a set of hundreds of absorption bands that are seen from the near-ultraviolet to near-infrared wavelengths. Their interstellar origin is well established, but the precise chemical identity of the DIB carriers remains to date one of the greatest unsolved mysteries in astronomical spectroscopy. These proceedings of IAU Symposium 297 include more than 70 contributions that cover a wide range of topics in observational astronomy and astrophysics; laboratory astrophysics and spectroscopy; astrochemistry; and theoretical, experimental and computational chemistry. This interdisciplinary overview contains all the required background material to make the volume an ideal starting point for researchers and graduate students to learn about the various aspects of DIBs and related topics.
Download or read book The Diffuse Interstellar Bands written by A.G.G.M. Tielens and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt: The mystery of the diffuse interstellar bands has been variously a curiosity, a co nundrum, and a nuisance for astronomers in the seven decades since the features were first noticed, but recently they have become a forefront issue in astrophysics. Ever since Paul Merrill, in a series of papers starting in 1934, pointed out the interstellar and unidentified nature of the bands, a Who's Who of twentieth century astronomers have tried their hands at solving the problem of identifying the carriers. Henry Norris Russell, Pol Swings, Otto Struve, Paul Ledoux, W. W. Morgan, Walter Adams, Jesse Greenstein, Lawrence Aller, and Gerhard Herzberg all briefly entered the stage, only to move on quickly to other problems where the chances for progress appeared more realistic. In more recent times a number of equally prominent scientists have pursued the bands, but generally only as a sideline to their real astronomical research. But in the past decade, and particularly in the past three years, the view of the search for the diffuse band absorbers as an interesting but perhaps quixotic quest has changed. Today there are several astronomers, as well as laboratory chemists, who are devoting substantial research time and resources to the problem and, as perhaps the most reliable indicator of the newly elevated status of research in this field, some research grants have now been awarded for the study of the bands.
Download or read book A Dirty Window written by Loris Magnani and published by Springer. This book was released on 2017-04-06 with total page 317 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an introduction to the physics of interstellar gas in the Galaxy. It deals with the diffuse interstellar medium which supplies a complex environment for exploring the neutral gas content of a galaxy like the Milky Way and the techniques necessary for studying this non-stellar component. After an initial exposition of the phases of the interstellar medium and the role of gas in a spiral galaxy, the authors discuss the transition from atomic to molecular gas. They then consider basic radiative transfer and molecular spectroscopy with particular emphasis on the molecules useful for studying low-density molecular gas. Observational techniques for investigating the gas and the dust component of the diffuse interstellar medium throughout the electromagnetic spectrum are explored emphasizing results from the recent Herschel and Planck missions. A brief exposition on dust in the diffuse interstellar medium is followed by a discussion of molecular clouds in general and high-latitude molecular clouds in particular. Ways of calibrating CO observations with the molecular hydrogen content of a cloud are examined along with the dark molecular gas controversy. High-latitude molecular clouds are considered in detail as vehicles for applying the techniques developed in the book. Given the transient nature of diffuse and translucent molecular clouds, the role of turbulence in the origin and dynamics of these objects is examined in some detail. The book is targeted at graduate students or postdocs who are entering the field of interstellar medium studies.
Download or read book The 3D Distribution of Interstellar Gas and Dust in the Galaxy written by Lucky Puspitarini and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multi-wavelength observations in emission of interstellar medium or matter (ISM) are providing increasingly detailed maps. Unfortunately, precise information on distances to the emitting clouds is still lacking. This leads to difficulties in interpreting and modeling ISM distribution and evolution. One way to obtain three-dimensional (3D) descriptions of the ISM, which comprise direction and distance information, is to record a large set of individual absorption measurements or reddening measurements toward target stars at various known distances and directions. These line-of-sight data give hints about the distribution of matter relative to the target star, and the inversion of these measurements using a robust tomographic method can provide the spatial distribution of the ISM. 3D ISM maps are a potential tool of wide use, but accurate and detailed maps are still lacking because absorption data are still limited and information of distances to the target stars are lacking or uncertain. The situation will greatly improve thanks to current and future massive stellar surveys from ground, and to the Gaia mission. Extracting interstellar (IS) absorption data from a large number of stellar spectra requires automated tools. Some of the works presented in this thesis contribute to the preparation of these tools. The tools are adapted to different IS tracers, such as NaI lines, CaII lines, and diffuse interstellar bands (DIBs). Despite their unknown carriers, DIBs are a promising tool to trace IS clouds, in particular at large distances as they are not easily saturated. IS lines or bands are usually extracted from early-type star spectra because of their smooth and easily fitted continua. However, early-type stars are a small fraction of the potential targets. The mean distance between them is too large to allow a good spatial resolution for the ISM mapping. Recently, progress was made on the extraction of IS tracers from late-type star spectra, in particular using a synthetic stellar spectrum. The spectral analysis tools are therefore adapted to different stellar spectrum types, early- or late-type star. Furthermore, we have developed a global analysis to fit multiple tracers simultaneously, allowing us to understand their relationships and to derive their kinematic information at the same time. Gaia is a mission of the European Space Agency (ESA) which was recently launched on 19th December 2013. Not only it will revolutionize our knowledge of the structure and the history of our Galaxy, but also of the distribution of ISM. It will provide precise distances which will greatly improve the constraints during the inversion. It will also provide spectroscopic data allowing the study of a particular DIB at 8620 \AA\ (Gaia DIB), providing more IS absorption data, and also photometric and spectroscopic information on a billion stars allowing accurate estimates of the extinction. Apart from the satellite, a support survey mission with a high-resolution ground-based spectrograph, the Gaia-ESO Spectroscopic Survey (GES), will provide a large number additional new IS absorption data that will be available for the 3D ISM maps. In this thesis, our spectral analysis tools were tested and applied to GES data and to various spectroscopic data from the TBL/NARVAL, OHP 1.93 m/ELODIE, and ESO 2.2 m/FEROS instruments, and from the GOSSS (Galactic O stars Spectroscopic Survey) project. The target stars are widely distributed in the sky, e.g., in southern sky, in high-latitude Galactic HI shells, and in the direction of specific objects, e.g., the M4 cluster, the Carina nebula, the NGC 4815 and gamma-Vel open clusters, and various fields like the CoRoT fields, the Galactic inner-disk or the bulge. Our results show that DIBs can trace the ISM distribution and kinematics at the Galactic scale. They can be used to trace the Galactic arms. Radial velocities of the DIBs were found in agreement with HI emission spectral features and gaseous IS NaI lines velocities.Finally, we tested the inversion method using simulated data and the reconstruction of the distribution. We also showed that 3D ISM maps are useful in many respects, not only in describing ISM distribution, but also helping to understand the physical and chemical conditions in the ISM. For example, our most recent 3D ISM map helps describing Gould Belt properties, nearby cavities or bubbles, and especially determining Local Bubble (LB) properties owing to the comparison with soft X-ray emission maps.
Download or read book Spectroscopic Studies of Interstellar Grains written by Fred M. Johnson and published by . This book was released on 1970 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Literature 1991 Part 2 written by Astronomisches Rechen-Institut and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 1592 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Astronomy and Astrophysics Abstracts" appearing twice a year has become oneof the fundamental publications in the fields of astronomy, astrophysics andneighbouring sciences. It is the most important English-language abstracting journal in the mentioned branches. The abstrats are classified under more than a hundred subject categories, thus permitting a quick survey of the whole extended material. The AAA is a valuable and important publication for all students and scientists working in the fields of astronomy and related sciences. As such it represents a necessary ingredient of any astronomical library all over the world.
Download or read book Wide Field Spectroscopy And The Distant Universe Proceedings Of The 35th Herstmonceux Conference written by S Maddox and published by World Scientific. This book was released on 1995-05-31 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt: Galaxies represent the most readily visible fabric of the cosmos. Their morphological types, luminosities and environmental surroundings contain valuable clues as to their origin and evolution. Locally, a strong correlation is seen between galaxy morphology and environmental location; this may have been molded at surprisingly modest redshifts. Spectroscopic and photometric studies of deep fields also suggest remarkably recent changes in the galaxy population. The associated growth of structure during the same interval can be tracked via X-ray studies of distant clusters of galaxies.Very recently, impressive observational facilities have been completed, each of which has extended the astronomers' dataset to look-back times where such evolutionary effects can be studied.This volume discusses surveys which share a common theme — the need for a large number of ground-based spectra. It focuses on the various approaches via a single theme concerned with the evolution of galaxies and their distribution. In the near future, impressive new observational facilities will be able to generate large statistical spectroscopic surveys, and the aim of this volume is to assess the scientific impact that ongoing and future spectroscopic surveys can make. Emphasis is placed on the role of non-optical and satellite facilities and the co-ordination of international efforts.
Download or read book The Spectroscopy of Interstellar Molecules written by Damian L. Kokkin and published by . This book was released on 2009 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Polycyclic Aromatic Hydrocarbons and Astrophysics written by A. Léger and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 405 pages. Available in PDF, EPUB and Kindle. Book excerpt: The near Infra-Red emission of the Interstellar Medium is a very puzzling subject. In the brightest regions, where spectroscopic observa tions are possible from the ground, several bands (3.3 - 3.4 - 6.2 - 7.7 - 8.6 - 11.3 ~m) have been observed since 1973. The absence of satisfying explanation was so obvious that they were called "Unidenti fied IR Emission Bands". The puzzle still increased when were known the first results of the general IR sky survey made by the satellite IRAS. On a large scale, the near IR emission of the Interstellar medium was expected to be very small but it was observed to be about one third of the total IR emission for our own galaxy ..• The situation has moved in 1984 when it was suggested that a class of stable organic molecules, the Polycyclic Aromatic Hydrocarbons (PAH's) could be at the origin of this near IR emission. Initially based on the required refractory character of particules that should be heated to high temperature without subliming, this hypothesis leads to a sugges tive spectroscopic similarity with the observed astronomical bands. This hypothesis is attractive and it has many implications, for ins tance, the PAHs would be the most abundant organic molecules in the universe. However, many points have to be clarified and the different consequences of this suggestion should be explored.
Download or read book The Dense Interstellar Medium in Galaxies written by Susanne Pfalzner and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 665 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Cologne-Bonn-Zermatt symposium is a well established series of conferences, occurring on a 5-year cycle, on the dense interstellar medium and related topics. The main results constitute valuable proceedings that offer everyone working in this field an authoritative and comprehensive source of reference.
Download or read book Encyclopedia of Astrobiology written by Muriel Gargaud and published by Springer Science & Business Media. This book was released on 2011-05-26 with total page 1890 pages. Available in PDF, EPUB and Kindle. Book excerpt: Astrobiology is a remarkably interdisciplinary field. This reference serves as a key to understanding technical terms from the different subfields of astrobiology, including astronomy, biology, chemistry, the geosciences and the space sciences.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 440 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The X ray Background written by Xavier Barcons and published by Cambridge University Press. This book was released on 1992-07-31 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: A review of the current observational knowledge and understanding of the cosmic X-ray background.
Download or read book Diffuse Matter in Galaxies written by J. Audouze and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of the interstellar medium is certainly one of the most recently developed astrophysical topics. Indeed, to understand the physical status of this medium, one should observe it at every wavelength, especially in radio and in the ranges which are only accessible from space such as Infra Red, X and gammas. Thanks to many new observations we now know that interstellar gas is quite inhomogeneous, since it is made from relatively cold and dense phases (interstellar clouds), surrounded by a relatively hot and tenuous medium. The summer school which took place from September 1 to 16 at the Institut d'Etudes Scientifiques of Cargese, and from which this book originates, was devoted to the analysis of this second diffuse, hot and tenuous component. The eleven sets of lectures which were presented at this school constitute the chapters of this book. They review different aspects (observations, determination of the physical properties and evolution) of this diffuse medium. In the first chapter, J. Lequeux (Marseille Observatory) introduces the study of the diffuse interstellar medium which plays a major role in galactic evolution. His contribution provides some historical references on this subject, such as a copious bibliography on the analysis and observations of the interstellar medium.
Download or read book Proceedings of the NASA Laboratory Astrophysics Workshop written by Farid Salama and published by . This book was released on 2002 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Literature 1997 Part 1 written by Astronomisches Rechen-InstitutARI and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 1746 pages. Available in PDF, EPUB and Kindle. Book excerpt: Astronomy and Astrophysics Abstracts is devoted to the recording, summarizing and indexing of astronomical publications throughout the world. Two volumes are scheduled to appear per year. Volume 67 records 10,903 papers covering besides the classical fields of astronomy and astrophysics such matters as space flights related to astronomy, lunar and planetary probes and satellites, meteorites and interplanetary matter, X rays and cosmic rays, quasars and pulsars. The abstracts are classified under more than one hundred subject categories thus permitting quick surveying of the bulk of material published on the same topic within six months. For instance, this volume records 119 papers on minor planets, 155 papers on supernovae, and 554 papers on cosmology.
