Dominant group/Astronomy

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The false color image shows a number of bright magnetic active regions on the Sun. Credit: NASA.

In theory, the relationship between the term dominant group and astronomy involves astronomical entities. This may be of two types: (1) a dominant group of astronomical entities, or (2) a dominant group in some way associated with astronomical entities.

Any astronomical dominant group, or its synonyms, is an astronomical entity.

Dominant groups[edit | edit source]

Examples from primary sources are to be used to prove or disprove each hypothesis. These can be collected per subject or in general.

  1. Accident hypothesis: dominant group is an accident of whatever processes are operating.
  2. Artifact hypothesis: dominant group may be an artifact of human endeavor or may have preceded humanity.
  3. Association hypothesis: dominant group is associated in some way with the original research.
  4. Bad group hypothesis: dominant group is the group that engages in discrimination, abuse, punishment, and additional criminal activity against other groups. It often has an unfair advantage and uses it to express monopolistic practices.
  5. Control group hypothesis: there is a control group that can be used to study dominant group.
  6. Entity hypothesis: dominant group is an entity within each field where a primary author of original research uses the term.
  7. Evolution hypothesis: dominant group is a product of evolutionary processes, such groups are the evolutionary process, produce evolutionary processes, or are independent of evolutionary processes.
  8. Identifier hypothesis: dominant group is an identifier used by primary source authors of original research to identify an observation in the process of analysis.
  9. Importance hypothesis: dominant group signifies original research results that usually need to be explained by theory and interpretation of experiments.
  10. Indicator hypothesis: dominant group may be an indicator of something as yet not understood by the primary author of original research.
  11. Influence hypothesis: dominant group is included in a primary source article containing original research to indicate influence or an influential phenomenon.
  12. Interest hypothesis: dominant group is a theoretical entity used by scholarly authors of primary sources for phenomena of interest.
  13. Metadefinition hypothesis: all uses of dominant group by all primary source authors of original research are included in the metadefinition for dominant group.
  14. Null hypothesis: there is no significant or special meaning of dominant group in any sentence or figure caption in any refereed journal article.
  15. Object hypothesis: dominant group is an object within each field where a primary author of original research uses the term.
  16. Obvious hypothesis: the only meaning of dominant group is the one found in Mosby's Medical Dictionary.
  17. Original research hypothesis: dominant group is included in a primary source article by the author to indicate that the article contains original research.
  18. Primordial hypothesis: dominant group is a primordial concept inherent to humans such that every language or other form of communication no matter how old or whether extinct, on the verge of extinction, or not, has at least a synonym for dominant group.
  19. Purpose hypothesis: dominant group is written into articles by authors for a purpose.
  20. Regional hypothesis: dominant group, when it occurs, is only a manifestation of the limitations within a region. Variation of those limitations may result in the loss of a dominant group with the eventual appearance of a new one or none at all.
  21. Source hypothesis: dominant group is a source within each field where a primary author of original research uses the term.
  22. Term hypothesis: dominant group is a significant term that may require a 'rigorous definition' or application and verification of an empirical definition.

Active regions[edit | edit source]

Notation: let the symbol AR stand for active region.

let the symbol SDR stand for surface differential rotation.
let the symbol ΔP stand for a change in rotational period.

"[A] star lacking one dominant AR, or with several ARs spaced in longitude, might not show a clear rotational signal."[1]

SDR "will most easily be detected among stars that have relatively stable modulation over several rotations within a season from a dominant group of ARs that experience a noticeable change in mean AR latitude (corresponding to a change in mean rotational period) between consecutive observing seasons."[1]

"On very active stars with large filling factors, ΔP may be minimized because the periods determined might only result from a limited latitude band where enough "gaps" in the plage exist to permit detection of rotation modulation."[1] ΔP equals the maximum observed rotational period (Pmax) minus the minimum (Pmin).[1]

Astrobiology[edit | edit source]

"The phylum Chloroflexi is a dominant group at organic-rich sites lacking hydrates."[2]

"Before the great oxidation event, a group of single-celled microorganisms, called methanogens were the dominant group of organisms in early earth."[3]

"The right hemispheric dominant group is hyperdigoxinemic, left hemispheric dominant group is hypodigoxinemic and bihemispheric dominant group is normodigoxinemic."[4]

Galactic cosmic rays[edit | edit source]

Notation: let the symbol Z stand for atomic number.

let the symbol PeV stand for 1015 electron volts.

"The most dominant group is the iron group (Z = 25 − 27), at energies around 70 PeV more than 50% of the all-particle flux consists of these elements."[5]

Galaxy groups[edit | edit source]

Notation: let the symbol keV stand for 103 electron volts.

Compact groups of galaxies are tight associations of galaxies.[6] Their compactness suggests extremely short crossing times and a very rapid evolution.[6] Computer simulations suggest that a compact "group coalesces into a giant dominant galaxy in a small number of crossing times."[6] "Alternately, compact groups may be transient unbound cores of loose groups".[6] A third alternative is that they are mostly chance alignments within larger loose groups of galaxies.[6]

"In a physically dense group one would expect that the majority of the galaxies would exhibit visible signs of interaction."[6]

"At the same time, the dominant group members are as likely to be spirals as ellipticals, hence suggesting that systematic merging has not (yet) occurred".[6]

"Regardless that their member galaxies are dominated by spiral galaxies, we detected extended thermal X-ray emission that is attributed to hot gas with a temperature of 1.04±0.10 keV."[7]

"This is the second clear detection of thermal X-ray emission from a spiral-dominant group of galaxies after HCG 92."[7]

"To that end we used the very compact 375-m array of the Australia Telescope Compact Array (ATCA; Frater et al. 1992)1 to search for intergalactic H I gas in the NGC 1808 group, conducting observations centred between NGC 1792 and NGC 1808, the two dominant group members."[8]

"The hard emission of the starburst galaxies can be divided into two groups; point source dominant and diffuse source dominant."[9]

"The X-ray luminosity of the dominant group [of galaxies] is an order of magnitude fainter than that of the X-ray jet."[10]

Interstellar medium[edit | edit source]

Interstellar dust can be studied by infrared spectrometry, in part because the dust is an astronomical infrared source and other infrared sources are behind the diffuse clouds of dust.

"In diffuse clouds the dominant group appears to be -CH3."[11]

Mira variables[edit | edit source]

A Mira variable, or Mira-type variable, is a class of pulsating variable stars characterized by very red colors, pulsation periods longer than a hundred days, and light amplitudes greater than one magnitude.

"The rotational transitions within vibrationally excited states of 28SiO (SiO hereafter) show intense maser emission in objects such as AGB stars, mostly O-rich Mira-type variables, as well as in a few star-forming regions."[12]

"The sample was made up of Mira-type variables, semiregular AGB stars, red supergiants and one star-forming region (Orion IRc2)."[12] "Of a total of 21 objects in the sample, we have covered more than 8 full cycles for 13 regular variables, mostly Mira-type stars."[12]

"The goal was to record between 10 and 15 spectra per pulsation cycle in Mira-type variables, the dominant group in the sample."[12]

Preflare spectrum[edit | edit source]

The microdensitometer tracings from a low-inductance vacuum spark are compared with spectra from the OSO 3 satellite.[13]

"The preflare spectrum and the 14 kV spectrum both have Fe XVIII as the dominant group of lines"[13]

Formation of binary stars[edit | edit source]

"A proposed mechanism for the formation of binary and multiple systems is that of 'prompt initial fragmentation'" of the dense molecular cloud during the formation of protostars in bound groups.[14] For a binary, the protostar fragments into two protostars which then collapse to form the binary system.[15]

"In almost all close encounters the energy and angular momentum transfer is dominated by disc material becoming unbound from the system, with the contributions from close disc particle - star encounters being significant."[14]

"The third is by far the dominant group, comprising 50 per cent of particles."[14]

Subdwarfs[edit | edit source]

"The dominant population" in the Palomar-Green Catalog of Ultraviolet Excess Stellar Objects "is that of the hot, hydrogen atmosphere subdwarfs, the sdB stars, which comprise nearly 40 percent of the sample."[16] "The helium-rich sdO stars account for 13% of the total. The hot white dwarfs of spectral types DA, DB, and DO account for 21%, 2.8%, and 1.0% of the sample; cooler DC or DZ white dwarfs add another 1.2%"[16]

The Palomar Green (PG) "survey is complete to B ≤ 16.2 for objects showing ultraviolet excesses U - B ≤ -0.4 for one-fourth of the sky at high galactic latitude".[17] There may be numerous cataclysmic variables (CVs) "with spectra predominantly in absorption in the PG catalog of over 1800 blue objects."[17]

"Many such objects might have been categorized as hot subdwarfs (sdB, sdO), the dominant group of PG objects, or as white dwarfs, because the initial spectral classifications were done at low resolution with spectra of highly variable quality."[17]

White dwarfs[edit | edit source]

"White dwarfs are end-products of stellar evolution. The fundamental properties of the dominant group of nonmagnetic white dwarfs have been invaluable in constraining the theory of single star evolution."[18] Of the 2551 white dwarf stars from the full spectroscopic white dwarf and hot subdwarf sample within the Sloan Digital Sky Survey (SDSS) first data release, DR1, 1888 are non-magnetic DA types and 171, non-magnetic DBs.[19] "White dwarfs are the most readily studied of the end products of stellar evolution. Investigations of white dwarfs have generally focused on the dominant group of the nonmagnetic variety for which realistic model atmospheres can be constructed and stellar parameters deduced."[20] "White dwarfs are intensively studied end products of stellar evolution. However, investigations of white dwarfs have generally focused on the dominant group of nonmagnetic stars for which realistic model atmospheres can be constructed and fundamental properties, such as their masses or interior chemical composition can be determined."[21]

Notation: accretion induced collapse (AIC).

binary millisecond pulsars (BMSPs).
white dwarf (WD).

"If we focus on BMSPs with WD companions, which is the dominant group in the observed sample, our results indicate birth rates that are ∼ 10 times higher for BMSPs that come from the AIC route."[22]

Genera differentia[edit | edit source]

The genera differentia for possible definitions or relative synonyms of "dominant group" fall into the following set of orderable pairs:

Genera differentia for "dominant group"[23]
Synonym for "dominant" Category Number Category Title Synonym for "group" Category Number Catgeory Title
“superior” 36 SUPERIORITY "arrangement" 60 ARRANGEMENT
“influential” 171 INFLUENCE "class" 61 CLASSIFICATION
“musical note” 462 HARMONICS "assembly" 74 ASSEMBLAGE
“most important” 670 IMPORTANCE "size" 194 SIZE
“governing” 739 GOVERNMENT "painting", "grouping" 572 ART
"master" 747 MASTER "association", "set" 786 ASSOCIATION
----- --- ------- "sect" 1018 RELIGIONS, CULTS, SECTS

Unless otherwise stated, the small group study designation such as "Astronomy" is placed at the beginning of the search stream, e.g., "astronomy class sect superior rules", without the quotes on Google Scholar. Another search stream with "astronomy" at the end may find fewer or slightly more articles.

Number of articles on Google scholar.
Genera Differentia Popularity in articles Small group study area Popularity "Dominant group" overlap Concept usage
class sect superior rules 89,200 Astronomy 22,700 488 22,212
class arrangement superior rules 196,000 Astronomy 24,200 200 24,000

In the first article, cited following: "class", "most of the optimization problems can be grouped into classes ... of similar complexity", "first class projects", and "classification"; "arrangement", "arrangement of observations", "the algorithms [for arrangement] are sensitive to the scientific policy"; "superior", "genetic algorithms are clearly superior if there is not a good knowledge of the main constraints in the scheduling of the observations."; "rules", "[t]he natural rules ... are selection of the best individuals [those better adapted to the scientific policy] of a population".[24]

Def. superior [algorithms] based on rules [of selection] for the arrangement of classes [of observations] are called a dominant group [of algorithms].

'Orderable' means that any synonym from within the first category can be ordered with any synonym from the second category to form an alternate term for "dominant group"; for example, "superior class", "influential sect", "master assembly", "most important group", and "dominant painting". "Dominant" falls into category 171. "Group" is in category 61. Further, any word which has its most or much more common usage within these categories may also form an alternate term, such as "ruling group", where "ruling" has its most common usage in category 739, or "dominant party", where "party" is in category 74. "Taxon" or "taxa" are like "species" in category 61. "Society" is in category 786 so there is a "dominant society".

"A related, but separate, definition relies on a linguistic identity that differs from that of the dominant society [5]."[25]

From theoretical astronomy, a "dominant group" is an astronomical entity which has many genera differentia words that may form orderable pairs that are alternate, relative, synonymous terms. Here are some examples:

Dominant species[edit | edit source]

  1. "At the low density given by the spherically symmetric wind model (see Table 1), the dominant species in the gas are atomic ions while as the gas number density increases, the recombination of ions takes place and the gas composition is governed by neutral-phase chemistry, that is, the dominant species are neutral atoms and molecules although electrons and some ions are still present in relatively large amounts (for example, C+, O+ and He+)."[26]
  2. "From the geometry and scaling laws the contribution of a clump of radius R to the number of particles N of each species is ... where ηC is the carbon abundance and we are implicitly assuming that all the carbon is in the form of the dominant species in each zone."[27]

Greatest group[edit | edit source]

"First of all there were only fifteen groups seen during the entire year [1901], north and south put together. Of these, seven were in the north, and the mean latitude for the north was 8.6°, exactly the latitude of one spot of the seven, and this very naturally, seeing that it was by far the greatest group of the year, the celebrated "eclipse group.""[28] Bold added. Eclipse group is also a relative synonym for dominant group.

Influential group[edit | edit source]

  1. "Finally, and perhaps most importantly, London was the institutional home of the most influential group of astronomers of the period: the Royal Astronomical Society."[29]
  2. "During the first five years (the 'formative era') the Branch flourished under the guidance of what was collectively the most influential group of amateur astronomers in the country."[30]

Hypotheses[edit | edit source]

  1. Dominant group in astronomy is limited to entities that dominant by some physical quantity such as size, characteristic, or numerousness.

See also[edit | edit source]

References[edit | edit source]

  1. 1.0 1.1 1.2 1.3 Robert A. Donahue, Steven H. Saar, and Sallie L. Baliunas (July 1996). "A Relationship between Mean Rotation Period in Lower Main-Sequence Stars and Its Observed Range". The Astrophysical Journal 466 (7): 384-91. doi:10.1086/177517. 
  2. Fumio Inagaki, Takuro Nunoura, Satoshi Nakagawa, Andreas Teske, Mark Lever, Antje Lauer, Masae Suzuki, Ken Takai, Mark Delwiche, Frederick S. Colwell, Kenneth H. Nealson, Koki Horikoshi, Steven D’Hondt, and Bo B. Jørgensen (February 21, 2006). "Biogeographical distribution and diversity of microbes in methane hydrate-bearing deep marine sediments on the Pacific Ocean Margin". Proceedings of the National Academy of Sciences of the United States of America 103 (8): 2815-20. doi:10.1073/pnas.0511033103. Retrieved 2012-04-23. 
  3. John Braswell (June 10, 2009). June 10, 2009 RESESS Program.,29. Retrieved 2012-04-23. 
  4. Ravikumar Kurup A., Parameswara Achutha Kurup (2011). "Actinide Dependent Shadow Biosphere of Archaea and Viroids and Hemispheric Dominance". Advances in Natural Science 4 (2): 45-51. doi:10.3968/j.ans.1715787020110402.242. Retrieved 2012-04-23. 
  5. Jörg R Hörandel, N N Kalmykov and A V Timokhin (April 2006). "The end of the galactic cosmic-ray energy spectrum-a phenomenological view". Journal of Physics: Conference Series 47 (1): 132-41. doi:10.1088/1742-6596/47/1/017. Retrieved 2011-12-31. 
  6. 6.0 6.1 6.2 6.3 6.4 6.5 6.6 Gary A. Mamon (August 1986). "Are compact groups of galaxies physically dense?". The Astrophysical Journal 307 (8): 426-30. doi:10.1086/164431. 
  7. 7.0 7.1 Yasushi FUKAZAWA, Naomi KAWANO, Akimitsu OHTO, and Hirofumi MIZUSHIMA (August 2002). "Extended Thermal X-Ray Emission from the Spiral-Dominant Group of Galaxies HCG 57". Publications of the Astronomical Society of Japan 54 (8): 527-32. Retrieved 2011-12-05. 
  8. Michael Dahlem, Matthias Ehle, and Stuart D. Ryder (July 2001). "A search for intergalactic H I gas in the NGC 1808 group of galaxies". Astronomy & Astrophysics 373 (7): 485-93. doi:10.1051/0004-6361:20010614. 
  9. Tatsuya Inui, Hironori Matsumoto, Takeshi Go Tsuru, Katsuji Koyama, Satoki Matsushita, Alison B. Peck, and Andrea Tarchi (February 2005). "Chandra Observation of the Starburst Galaxy NGC 2146". Publications of the Astronomical Society of Japan 57 (1): 135-45. 
  10. A. Finoguenov, M.G. Watson, M. Tanaka, C.Simpson, M. Cirasuolo, J.S. Dunlop, J.A. Peacock, D. Farrah, M. Akiyama, Y. Ueda, V. Smolčič, G. Stewart, S. Rawlings, C.vanBreukelen, O. Almaini, L.Clewley, D.G. Bonfield, M.J. Jarvis, J.M. Barr, S. Foucaud, R.J. McLure, K. Sekiguchi, E. Egami (April 2010). "X-ray groups and clusters of galaxies in the Subaru-XMM Deep Field". Monthly Notices of the Royal Astronomical Society 403 (4): 2063-76. doi:10.1111/j.1365-2966.2010.16256.x. Retrieved 2011-12-09. 
  11. Duley, W. W. & Williams, D. A. (July 1981). "The infrared spectrum of interstellar dust - Surface functional groups on carbon". Royal Astronomical Society, Monthly Notices 196 (7): 269-74. 
  12. 12.0 12.1 12.2 12.3 J. R. Pardo, J. Alcolea, V. Bujarrabal, F. Colomer, A. del Romero, and P. de Vicente (September 2004). "28SiO v = 1 and v = 2, J= 1–0 maser variability in evolved stars. Eleven years of short spaced monitoring". Astronomy & Astrophysics 424 (9): 145-56. doi:10.1051/0004-6361:20040309. Retrieved 2011-08-16. 
  13. 13.0 13.1 U. Feldman and L. Cohen (January 1968). "An Iron Spark Line List in the 10-18 Å Range and its Comparison with Flare Spectra". The Astrophysical Journal 151 (1): L55-8. doi:10.1086/180140. 
  14. 14.0 14.1 14.2 S.M. Hall, C.J. Clarke and J.E. Pringle (January 1996). "Energetics of star-disc encounters in the non-linear regime". Monthly Notices of the Royal Astronomical Society 278 (1): 303-20. 
  15. J. E. Pringle (July 1989). "On the formation of binary stars". Royal Astronomical Society, Monthly Notices 239 (7): 361-70. 
  16. 16.0 16.1 Richard F. Green, Maarten Schmidt, and James Liebert (June 1986). "The Palomar-Green catalog of ultraviolet-excess stellar objects". The Astrophysical Journal Supplement Series 61 (6): 305-52. doi:10.1086/191115. 
  17. 17.0 17.1 17.2 Donald H. Ferguson, Richard F. Green, and James Liebert (December 1984). "Hot subdwarfs in detached binary systems and thick-disk cataclysmic variables from the Palomar-Green survey". The Astrophysical Journal 287 (12): 320-33. doi:10.1086/162691. 
  18. S. V. Berdyugina, A. V. Berdyugin, and V. Piirola (August 2007). "Molecular Magnetic Dichroism in Spectra of White Dwarfs". Physical Review Letters 99 (9): 091101-1 to -5. doi:10.1103/PhysRevLett.99.091101. Retrieved 2011-08-10. 
  19. S. J. Kleinman, Hugh C. Harris, Daniel J. Eisenstein, James Liebert, Atsuko Nitta, Jurek Krzesi ́nski, Jeffrey A. Munn, Conard C. Dahn, Suzanne L. Hawley, Jeffrey R. Pier, Gary Schmidt, Nicole M. Silvestri, J. Allyn Smith, Paula Szkody, Michael A. Strauss, G. R. Knapp, Matthew J. Collinge, A. S. Mukadam, D. Koester, Alan Uomoto, D. J. Schlegel, Scott F. Anderson, J. Brinkmann, D.Q. Lamb, Donald P. Schneider, and Donald G. York (May 2004). "A Catalog of Spectroscopically Identified White Dwarf Stars in the First Data Release of the Sloan Digital Sky Survey". The Astrophysical Journal 607 (1): 426-44. doi:10.1086/383464. Retrieved 2011-08-10. 
  20. D. T. Wickramasinghe and Lilia Ferrario (July 2000). "Magnetism in Isolated and Binary White Dwarfs". Publications of the Astronomical Society of the Pacific 112: 873-924. doi:10.1086/316593. Retrieved 2011-08-10. 
  21. Śliwiński M.S., Krzyczkowska L.I. (October 2004). Yu. Glagolevskij, D. Kudryavtsev, I. Romanyuk, Nizhnij Arkhyz. ed. The movie about the magnetism in isolated white dwarfs, In: Magnetic stars, Proceedings of the International Conference, held in the Special Astrophysical Observatory of the Russian AS, August 27-31, 2003. pp. 268-71. Retrieved 2011-08-10. 
  22. D T Wickramasinghe, Jarrod R Hurley, Lilia Ferrario, Christopher A Tout and Paul D Kiel (2009). [ "Accretion induced collapse of white dwarfs in binary systems and their observational properties"]. Journal of Physics: Conference Series 172 (1): 1-4. doi:10.1088/1742-6596/172/1/012037. Retrieved 2011-12-31. 
  23. Peter Mark Roget (1969). Lester V. Berrey and Gorton Carruth. ed. Roget's International Thesaurus, third edition. New York: Thomas Y. Crowell Company. pp. 1258. Retrieved 2011-08-26. 
  24. A. I. Gómez de Castro and J. Yáñez (2003). "Optimization of telescope scheduling Algorithmic research and scientific policy". Astronomy & Astrophysics 403: 357-67. doi:10.1051/0004-6361:20030319. Retrieved 2011-11-19. 
  25. Mariam Naqshbandi, Stewart B. Harris, James G. Esler, Fred Antwi-Nsiah (October 2008). "Global complication rates of type 2 diabetes in Indigenous peoples: A comprehensive review". Diabetes Research and Clinical Practice 82 (1): 1-17. doi:10.1016/j.diabres.2008.07.017. PMID 18768236. Retrieved 2011-12-23. 
  26. I. Cherchneff, Y.H. Le Teuff, P.M. Williams, and A.G.G.M. Tielens (May 2000). "Dust formation in carbon-rich Wolf-Rayet stars. I. Chemistry of small carbon clusters and silicon species". Astronomy and Astrophysics 357 (5): 572-80. 
  27. Alberto D. Bolatto, James M. Jackson and James G. Ingalls. "A semianalytical model for the observational properties of the dominant carbon species at different metallicities". The Astrophysical Journal. Retrieved 2011-12-05. 
  28. E. Walter Maunder (1903). "Spoerer's law of zones". The Observatory 26 (334): 329-30. 
  29. Mari E.W. Williams (March 1987). "Astronomy in London: 1860-1900". Quarterly Journal of the Royal Astronomical Society 28 (1): 10-26. 
  30. Wayne Orchiston and J. Perdix (April 2002). "A history of the British Astronomical Association in Australia: the fate of the Branches". Journal of the British Astronomical Association 112 (2): 68-77. 

Further reading[edit | edit source]

External links[edit | edit source]

{{Dominant group}}{{Terminology resources}}