2,331 research outputs found
Stellar Populations in Bulges
We present line strengths in the bulges and inner disks of 38 galaxies in the
local universe, including several galaxies whose bulges were previously
identified as being disk-like in their colors or kinematics, to see if their
spectral properties reveal evidence for secular evolution. We find that red
bulges of all Hubble types are similar to luminous ellipticals in their central
stellar populations. They have large luminosity-weighted ages, metallicities,
and alpha/Fe ratios. Blue bulges can be separated into a metal-poor class that
is restricted to late-types with small velocity dispersion and a young,
metal-rich class that includes all Hubble types and velocity dispersions.
Luminosity-weighted metallicities and alpha/Fe ratios are sensitive to central
velocity dispersion and maximum disk rotational velocity. Red bulges and
ellipticals follow the same scaling relations. We see differences in some
scaling relations between blue and red bulges and between bulges of barred and
unbarred galaxies. Most bulges have decreasing metallicity with increasing
radius; galaxies with larger central metallicities have steeper gradients.
Where positive age gradients (with the central regions being younger) are
present, they are invariably in barred galaxies. The metallicities of bulges
are correlated with those of their disks. While this and the differences
between barred and unbarred galaxies suggest that secular evolution cannot be
ignored, our results are generally consistent with the hypothesis that mergers
have been the dominant mechanism responsible for bulge formation.Comment: 30 pages, 21 figures; submitted to MNRA
Electronic document delivery systems
Discusses need of document delivery systems and its important functions. What is the importance of Electronic document delivery system.What all are the major steps involved in EDDS.Various kinds of EDDS
towards a change
During the past forty
two years, the Journal has firmly established itself as one of the premier
research publications (and only one of its kind) in India. It is also covered by
many international secondary journals, such as INSPEC Science Abstracts
(Parts A, B&C); Mathematical Reviews, Chemical Abstracts, Engineering
Index and COMPENDEX, BIOSIS, Indian Science Abstracts, etc
Of references and intellectual debts
A reference is a formal description of a document source with a set of
elements in a standardised sequence.It is an integral part of a research
paper and plays an important role in its life. It enables the readers to identify,
locate, understand and decide whether the cited paper should be consulted
or not
Commemorative Issue of Defence Science Journal on Golden Jubilee of DRDO
Defence Research and Development Organisation(DRDO), Ministry of Defence, is dedicatedly working towards enhancing self-reliance in Defence systems. DRDO undertakes design and development leading to production of world class weapon systems and equipment in accordance withthe expressed needs and the qualitative requirements laid  down by the three Services. The vision of DRDO is tomake India prosperous by establishing world class science and technology base and provide the Defence Services a decisive edge by equipping them with internationally competitive systems and solutions.Defence Science Journal, 2010, 60(2), pp.121-123, DOI:http://dx.doi.org/10.14429/dsj.60.34
Library Automation in lndia
This paper discusses about the Library automation movement in India. It discusses the growth of computers in the country when it came in to the libraries, development of library automation software in India. It also gives a list of library software packages available in India and its features also. It tells about what all are the advantages of the library Automation
Defence Science Journal: Sixty Successful Years of Publication
Its objective is to stimulate study and research in science fundamental and appliedin relation to the problems of Defence. It serves to bring to the notice of the scientists in universities and other research institutions the basic problems in Defence science, the work that is being done in this field and its importance and also the role of Defence Science in the progress of science generally. A properly conducted Defence Science Journal will go a long way in creating and sustaining interest amongst the research workers in universities and civil institutions, in Defence Science and Technology.Defence Science Journal, 2009, 59(4), pp.321-325, DOI:http://dx.doi.org/10.14429/dsj.59.152
Towards a standard style for bibliographic references
This paper discusses the need for a standard style for bibliographic references (BRs) or citations given usually at the end of a journal article or a chapter of a book. It also suggests to authors, editors and publishers some ways in which standardization in the preparation of BRs can be achieved
The role of DESIDOC in science .communication
information is a vital resource for research and development Scientists need information on the work being done or already done elsewhere to avoid repetition aid to corroborate their work. Such information made available at the right time , in the right form would results in more efficient and fruitful R&D programme
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