EBookClubs

Read Books & Download eBooks Full Online

EBookClubs

Read Books & Download eBooks Full Online

Book Study of the Far Infrared Emission of Nearby Spiral Galaxies

Download or read book Study of the Far Infrared Emission of Nearby Spiral Galaxies written by Willie Drouhet and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In my PHD work I explored the links between the physical properties of interstellar dust and other components of nearby spiral galaxies especially their stellar content. I worked on 46 disk galaxies from KINGFISH with IRAC/MIPS/PACS/SPIRE maps (3.6 - 500 microns). A bias is usually introduced in estimating disk orientations by using only a single surface brightness isophote. Thus I devised different surface brightness levels separated by constant steps in surface brightness and extracted isophotes at these levels in all FIR maps as well as in all IRAC 4.5 microns maps. To further assess the coherence of the shapes of isophotes across galactic disks, I built a quantitative indicator of the difference in shape between two ellipses with same center and same semi-major axis.I defined an acceptable level of difference between isophote shapes, by comparing disk orientations found in litterature. Using this level, I found regions inside the galactic disks where the isophotal shapes are similar. From these, I extracted one disk orientation per wavelength band. I found in the vast majority of the disk galaxy maps, be it dominated by stellar or dust emission, that a large fraction of the isophotes I extracted are coherent with the idea of an underlying disk. Comparing, for each galaxy, disk orientations extracted at all wavelengths, I found evidence in 20 galaxies out of 46, that on radial ranges as large as 1/3 of the visible disk (as measured by R25), the shapes of isophotes are morphologically similar. Thus for these 20 galaxies I devised consistent disk orientations both for the stellar and dust content. These 20 galaxies are less luminous, less emitting in the IR w.r.t. the optical, less barred, and characterized by later stage types than average. I also found that the disk orientations devised by my photometric method yield results more similar to H-alpha kinematic orientations than other photometric studies based on a single isophote level.Using the orientations I found and H-alpha dynamics disk orientations, I averaged azimuthally surface brightnesses to produce radial spectral energy distributions (SED) profiles. Once fitted with a cosmic dust emission model, they resulted in radial profiles of dust and stellar content properties. I found the dust intercepted power to be proportionnal to the product of the total dust mass and the average ISRF shining on dust. This former quantity is better correlated with the bolometric stellar luminosity than any of the dust mass or the dust heating ISRF separately. Thus the old stellar populations may be an important heating source for dust. The power intercepted by dust is also very well correlated with the total infrared power. The dust intercepts a larger quantity of power coming from stars in more actively star forming galaxies.Dust exhibit radial mass surface density profiles less well described by Sersic functions than stellar ones. When both profiles are well fitted by Sersic functions, stellar density profiles have smaller half mass radii than the isophotal optical radius (R25) separately in later type galaxies, but also in more quiescent galaxies. Sersic index and half mass radius distributions have larger widths for dust than for stellar surface density profiles.I also found that the ratio of dust over stellar surface density is an important factor to explain the variations with galactic morphological type of the ratio of dust intercepted power over the power emitted by old stellar populations. This later link could be intertwined with spiral structure strength in stage types later than 2.

Book Spectral Modeling of Dusty Galaxies  and Evolution of the Far Infrared radio Correlation

Download or read book Spectral Modeling of Dusty Galaxies and Evolution of the Far Infrared radio Correlation written by Douglas James Peter O'Rourke and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book An Investigation of the Source of the Far Infrared Radiation in Spiral Galaxies Using Near Infrared Hydrogen Recombination Lines as a Probe of Star Formation

Download or read book An Investigation of the Source of the Far Infrared Radiation in Spiral Galaxies Using Near Infrared Hydrogen Recombination Lines as a Probe of Star Formation written by Lauren V. Jones and published by . This book was released on 2000 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Scientific and Technical Aerospace Reports

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Physics Briefs

Download or read book Physics Briefs written by and published by . This book was released on 1993 with total page 1058 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Literature 1988  Part 2

    Book Details:
  • Author : Astronomisches Rechen-Institut
  • Publisher : Springer Science & Business Media
  • Release : 2013-06-29
  • ISBN : 3662123673
  • Pages : 1308 pages

Download or read book Literature 1988 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 1308 pages. Available in PDF, EPUB and Kindle. Book excerpt: From the reviews: "Astronomy and Astrophysics Abstracts has appeared in semi-annual volumes since 1969 and it has already become one of the fundamental publications in the fields of astronomy, astrophysics and neighbouring sciences. It is the most important English-language abstracting journal in the mentioned branches. ...The abstracts 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." Space Science Reviews#1 "Dividing the whole field plus related subjects into 108 categories, each work is numbered and most are accompanied by brief abstracts. Fairly comprehensive cross-referencing links relevant papers to more than one category, and exhaustive author and subject indices are to be found at the back, making the catalogues easy to use. The series appears to be so complete in its coverage and always less than a year out of date that I shall certainly have to make a little more space on those shelves for future volumes." The Observatory Magazine#2

Book International Aerospace Abstracts

Download or read book International Aerospace Abstracts written by and published by . This book was released on 1999 with total page 934 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book The Evolution of Galaxies and Their Environment

Download or read book The Evolution of Galaxies and Their Environment written by David J. Hollenbach and published by . This book was released on 1993 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Atlas of Galaxies

    Book Details:
  • Author : Ronald J. Buta
  • Publisher : Cambridge University Press
  • Release : 2007-03-08
  • ISBN : 0521820480
  • Pages : 13 pages

Download or read book Atlas of Galaxies written by Ronald J. Buta and published by Cambridge University Press. This book was released on 2007-03-08 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: New illustrated atlas on modern galaxy classification for astronomy researchers, students, and amateurs.

Book A Panchromatic View of Galaxies

Download or read book A Panchromatic View of Galaxies written by Alessandro Boselli and published by John Wiley & Sons. This book was released on 2012-01-17 with total page 343 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describing how to investigate all kinds of galaxies through a multifrequency analysis, this text is divided into three different sections. The first describes the data currently available at different frequencies, from X-rays to UV, optical, infrared and radio millimetric and centimetric, while explaining their physical meaning. In the second section, the author explains how these data can be used to determine physical parameters and quantities, such as mass and temperature. The final section is devoted to describing how the derived quantities can be used in a multifrequency analysis to study such physical processes as the star formation cycle and constrain models of galaxy evolution. As a result, observers will be able to interpret galaxies and their structure.

Book Government Reports Announcements   Index

Download or read book Government Reports Announcements Index written by and published by . This book was released on 1995-06 with total page 548 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Nuclear Science Abstracts

Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1976-04 with total page 912 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Highlights of Spanish Astrophysics V

Download or read book Highlights of Spanish Astrophysics V written by Jose M. Diego and published by Springer Science & Business Media. This book was released on 2010-03-18 with total page 466 pages. Available in PDF, EPUB and Kindle. Book excerpt: Astronomy is a scienti?c discipline that has developed a rapid and impressive growth in Spain. Thirty years ago, Spain occupied a purely anecdotal presence in the international context, but today it occupies the eighth position in the world in publication of astronomical articles, and, among other successes, owns and op- ates ninety per cent of the world’s largest optical telescope GTC (Gran Telescopio Canarias). The Eighth Scienti?c Meeting of the Spanish Astronomical Society (Sociedad Espanol ̃ a de Astronom ́ a, SEA), held in Santander in July 7–11 2008, whose p- ceedings are in your hands, clearly shows the enthusiasm, motivation and quality of the present Spanish astronomical community. The event brought together 322 participants, who represent almost 50% of Spanish professional astronomers. This percentage, together with the continuously increasing, with respect to previous SEA meetings, number of oral presentations and poster contributions (179 and 127 respectively), con?rms that the SEA conferences have become a point of reference to assess the interests and achievements of astrophysical research in Spain. The most important and current topics of modern Astrophysics were taken into accountat thepreliminarymeeting,aswell as the numberandqualityofparticipants and their contributions, to select the invited speakers and oral contributors. We took a week to enjoy the high quality contributions submitted by Spanish astronomers to the Scienti?c Organizing Committee. The selection was dif?cult. We wish to acknowledge the gentle advice and commitment of the SOC members.