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Journal articles on the topic 'Stav objektu'

Author: Grafiati

Published: 4 June 2021

Last updated: 5 February 2022

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1

Rameš, Václav. "(Post)socialist economists as an object of historical studies. Current state of affairs and future outlooks." Soudobé dějiny 24, no. 3 (September 1, 2017): 389–402. http://dx.doi.org/10.51134/sod.2017.019.

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2

Racz, Aleksandar, Dora Smolčić Jurdana, and Krešimir Rotim. "Razlike u stavovima o klimatskim promjenama kod menadžera u turističkim smještajnim objektima različitih kategorija." Journal of applied health sciences 7, no. 2 (April 23, 2021): 151–60. http://dx.doi.org/10.24141/1/7/2/5.

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U novije doba, više nego ikad ranije, klimatske su promjene globalnog karaktera i ozbiljno determiniraju razvoj i budućnost turizma u širem obuhvatu turističkih regija i svijetu u cjelini. Klimatske promjene ne predstavljaju samo hipotetski akademski izazov za čovječanstvo, već direktno utječu na sve aspekte ljudskog života, uključujući turizam, koji i sam postaje globalni ekološki problem. U ovom radu fokus interesa bio je usmjeren na istraživanje postojanja povezanosti između kategorije smještajnog objekta izražene zvjezdicama s iskazanim uvjerenjima i stavovima menadžera o klimatskim promjenama i međuutjecaju klimatskih promjena i turizma. U istraživanju je postavljena hipoteza prema kojoj postoje znatne razlike u uvjerenjima i stavovima o klimatskim promjenama i međuutjecaju klimatskih promjena i turističkog smještaja, kao i o klimatskim promjenama kao determinantama oblikovanja turističke ponude između menadžera u različitim kategorijama (dvije do pet zvjezdica) turističkih smještajnih kapaciteta (hoteli, aparthoteli, turistička naselja, kampovi ili marine). Stoga je specifični cilj istraživanja bio utvrditi utječu li kategorija različitih turističkih smještajnih kapaciteta (hoteli, aparthoteli, turistička naselja, kampovi ili marine) na uvjerenja i stavove menadžera o pitanjima klimatskih promjena i međuutjecaju klimatskih promjena i turističkog smještaja, kao i o klimatskim promjenama kao determinantama oblikovanja turističke ponude. Područje provođenja istraživanja bilo je prostorno određeno na cijelom području Republike Hrvatske i na ukupnoj populaciji svih kategoriziranih turističkih smještajnih objekata, odnosno na 1084 kategorizirana objekta na dan 7. ožujka 2019. prema kategorizaciji koju je provelo Ministarstvo turizma RH. Prikupljanje podataka bilo je provedeno metodom e-anketiranja, pri čemu je od ukupnog broja poslanih anketnih upitnika uredno bilo ispunjeno 283 upitnika, što je predstavljalo odaziv od 26,1 %. U skladu s postavljenom hipotezom i ciljem istraživanja dokazano je postojanje znatnih razlika u stavovima menadžera koji upravljaju turističkim smještajnim objektima koji imaju različitu kategorizaciju, odnosno različit broj dodijeljenih zvjezdica, i to po svim tvrdnjama o kojima su izrazili svoj stav, u sve tri komponente stava. Uvjerenja i stavovi menadžera u smještajnoj turističkoj industriji funkcija su raznih karakteristika smještajnog objekta, pri čemu snažnije proekološke stavove i veću razinu ekološke svijesti o klimatskim promjenama i međuutjecaju klimatskih promjena i turističkog smještaja, kao i o klimatskim promjenama kao determinantama oblikovanja turističke ponude pokazuju menadžeri zaposleni u smještajnim turističkim kategoriziranim objektima s višom kategorijom, odnosno većim brojem zvjezdica.

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3

Zakharov, A. F., and M. V. Sazhin. "Noncompact Objects as Microlenses." Symposium - International Astronomical Union 183 (1999): 168. http://dx.doi.org/10.1017/s0074180900132486.

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The first results of observations of microlensing have discovered a phenomenon, predicted in the papers of Byalko (1969) and Paczynsky (1986). A character of the gravitational microlens is unknown till now, although the most widespread hypothesis assumes that they are compact dark objects as brown dwarfs. Nevertheless, they could be presented by another objects, in particular, an existence of the dark objects consisting of the super symmetrical weakly interacting particles (neutralino) has been recently discussed in the papers of Gurevich et al. We consider microlensing by a neutralino star in framework of a rough model which is rather clear and we obtain analytical expressions for results. We approximate the density of distribution mass of a neutralino star in formwhere r is the current value of a distant from star's center, ρo is mass density of a neutralino star for distance a0 from a center, an is a “radius” neutralino star. The detailed analysis of the model is presented in the papers of Zakharov & Sazhin (1996a, 1996b). This research has been supported in part by Russian Foundation of Fundamental Research (grant N 96-02-17434).

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4

Cordes, James M., David Chernoff, and Zaven Arzoumanian. "Neutron Star Population Dynamics." International Astronomical Union Colloquium 160 (1996): 55–56. http://dx.doi.org/10.1017/s0252921100041026.

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AbstractWe summarize our efforts at understanding the galactic neutron star (NS) population using likelihood and bayesian analyses. These include determination of the velocity distribution of young, high-magnetic field objects; the spatial, velocity, period and luminosity distributions of millisecond pulsars; and a full analysis of high-field objects including modeling of pulsars’ radio beams with the implicit assumption that such objects, for fixed period and period derivative, are standard candles.

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5

Bjekić, Jovana, Marko Živanović, and Iris Žeželj. "ODNOS EKSPLICITNIH I IMPLICITNIH MERA STAVA PREMA HOMOSEKSUALNOSTI I VERBALNE PRODUKCIJE." Primenjena psihologija 9, no. 2 (July 7, 2016): 141. http://dx.doi.org/10.19090/pp.2016.2.141-161.

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Veliki broj istraživanja pokazuje da eksplicitni i implicitni stavovi determinišu ponašanje. Verbalna produkcija, kao bihejvioralna manifestacija unutrašnjeg sveta osobe prema savremenim psiholingvističkim teorijama predstavlja, kako nameran, tako i automatski proces. Cilj ovog istraživanja bilo je ispitivanje odnosa između različitih mera verbalnog ponašanja u vezi sa homoseksualnošću, sa jedne, i implicitnih i eksplicitnih mera stava prema homoseksualnosti sa druge strane. U istraživanju je učestvovalo 105 ispitanika. Kao mere stava korišćeni su Test homofobije (H25) i Test Implicitnih Asocijacija, dok su mere verbalne produkcije ekstrahovane iz dve eksperimentalne situacije korišćenjem programa za automatsku analizu teksta LIWCser. U prvoj eksperimentalnoj situaciji ispitanici su indirektno usmeravani na stavski objekat (homoseksualnost), dok su u drugoj situaciji instruisani da direktno govore o stavskom objektu. Rezultati su pokazali umerenu povezanost između eksplicitnih i implicitnih mera stava, kao i relativno nisku do umerenu povezanost ovih mera sa pojedinačnim merama verbalne produkcije. Dodatno, pokazalo se da u osnovi verbalne produkcije stoje implicitni i eksplicitni procesi i to da su spontani aspekti verbalne produkcije pre svega vođeni implicitnim procesima, dok namerni aspekti verbalne produkcije predstavljaju manifestaciju eksplicitnih stavova. Dobijeni rezultati u skladu su sa postojećim modelima odnosa implicitnih i eksplicitnih mera stavova i ponašanja, kao i savremenim psiholingvističkim teorijama.

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6

Hegedüsová, Iveta, and Sergej Priganc. "ZHODNOTENIE STAVU STROPNÝCH PANELOV V AGRESÍVNOM PROSTREDÍ." Czech Journal of Civil Engineering 1, no. 2 (December 31, 2015): 26–31. http://dx.doi.org/10.51704/cjce.2015.vol1.iss2.pp26-31.

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V článku sú prezentované výsledky chemickej analýzy betónových vzoriek odobratých z existujúcich stropných panelov. Panely sú súčasťou nosného systému poľnohospodárskeho ustajňovacieho objektu. Analýza sa previedla za účelom preukázania nepriaznivého vplyvu agresívneho prostredia na betónovú nosnú konštrukciu.

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7

Apparao, Krishna M. V., and S. P. Tarafdar. "Effect of Compact Objects Near Be Stars." International Astronomical Union Colloquium 92 (August 1987): 516–18. http://dx.doi.org/10.1017/s0252921100116720.

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Several Be stars are identified with bright X-ray sources. (Rappaport and Van den Heuvel, 1982). The bright X-ray emission and observed periodicities indicate the existence of compact objects (white dwarfs, neutron stars or black holes) near the Be stars. A prime example is the brightest X-ray source A0538-66 in LMC, which contains a neutron star with a rotation period of 59 ms. Apparao (1985) explained the X-ray emission, which occurs in periodic flares, by considering an inclined eccentric orbit for the neutron star around the assumed Be-star. The neutron star when it enters a gas ring (around the Be-star) accreting matter giving out X-rays.The X-ray emission from the compact objects, when the gas ring from the Be-star envelopes the objects, has interesting consequences. The X-ray emission produces an ionized region (compact object Stromgren sphere or COSS) in the gas surrounding the compact object (CO).

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8

Shelke, Pradip B. "Random sequential adsorption of n-star objects." Surface Science 644 (February 2016): 34–40. http://dx.doi.org/10.1016/j.susc.2015.09.013.

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9

Sone, Yuji. "More than objects: Robot performance in Japan's Bacarobo Theatre." Studies in Theatre and Performance 30, no. 3 (November 1, 2010): 341–53. http://dx.doi.org/10.1386/stap.30.3.341_1.

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10

Shu, Frank H. "Theory of Protostellar Objects." International Astronomical Union Colloquium 89 (1986): 10–34. http://dx.doi.org/10.1017/s0252921100086000.

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AbstractMany problems in the theory of star formation are amenable to a complementary attack in which the analytical approach is used to reduce the governing equations to a form amenable to efficient numerical solution. This strategy has proven very useful in helping to resolve several astrophysical puzzles which arise because the bulk of star formation today is observed to occur, with relatively low efficiency, in giant molecular cloud complexes. How does a cloud of 105-106M⊙ know how to form stars of mass ~ 1 M⊙? How does the interstellar medium know, to one or two orders of magnitude, that roughly hydrogen atoms of mass mH are needed to yield thermonuclear fusion in a self-gravitating ball of gas? Why have radio astronomers not detected unambiguous evidence for the collapse motions attendant to star formation? Why has a true protostar, the “holy grail” of infrared astronomy, been so hard to find? Why do young stellar objects almost universally exhibit powerful outflows? Why is the geometry for these outflows often bipolar? Why do T Tauri stars have such active chromospheres? In this review we suggest that these puzzles all have a related resolution, in the nature of how gravitational collapse is initiated and terminated in the slowly rotating cores of molecular clouds.

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11

Pinheiro, F. J. G., D. F. M. Folha, M. J. P. F. G. Monteiro, M. Marconi, V. Ripepi, and F. Palla. "Oscillations in Young Stellar Objects." International Astronomical Union Colloquium 185 (2002): 352–53. http://dx.doi.org/10.1017/s0252921100016493.

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AbstractWe report the discovery of periodicities in the light curve of the Herbig Ae star V346 Ori. We interpret these variations as the superposition of at least two signals with periods P1=42±6 min and P2=68±12 min resulting from stellar oscillations. The computation of linear non-adiabatic pulsation models for Pre-Main Sequence (PMS) stars reproduces these periods for a 1.5 M⊙ star with Teff= 7300 K and log L/L⊙= 0.74, pulsating in the fundamental and second overtones.

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12

Yorke, Harold W., and Thomas Henning. "Opacity Problems in Protostellar Objects." International Astronomical Union Colloquium 146 (1994): 186–95. http://dx.doi.org/10.1017/s0252921100021321.

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Opacity influences the transfer of radiation and is thus of decisive importance for (a) the interpretation of astronomical observations, (b) determining the thermal structure, (c) critically influencing molecular, atomic and thermonuclear processes and (d) affecting the overall dynamic evolution during the star formation process. Questions pertaining to the onset of instability of gas clouds, their subsequent fragmentation into smaller clumps, the formation of multiple systems, the initial mass function (IMF), the upper and lower mass limits, star formation efficiency and the fate of material not collected into stars cannot be considered without intimate knowledge of the opacity in this environment.

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13

Tissera, Patricia B. "Analysis of Star Formation in Galaxy‐like Objects." Astrophysical Journal 534, no. 2 (May 10, 2000): 636–49. http://dx.doi.org/10.1086/308774.

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14

Hubler, Alfred, and Maja Tomicic. "Star-shaped solids: Objects with a negative dimension." Complexity 19, no. 3 (December 14, 2013): 7–9. http://dx.doi.org/10.1002/cplx.21488.

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15

Fang, Lincong, Dominique Michelucci, and Sebti Foufou. "An improved star test for implicit polynomial objects." Computer-Aided Design 70 (January 2016): 161–70. http://dx.doi.org/10.1016/j.cad.2015.07.005.

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16

Tamura, Motohide, Yoichi Itoh, Yumiko Oasa, Alan Tokunaga, and Koji Sugitani. "Very Low-Luminosity Objects in Star-Forming Regions." Highlights of Astronomy 11, no. 1 (1998): 423–24. http://dx.doi.org/10.1017/s1539299600021626.

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AbstractIn order to tackle the problems of low-mass end of the initial mass function (IMF) in star-forming regions and the formation mechanisms of brown dwarfs, we have conducted deep infrared surveys of nearby molecular clouds. We have found a significant population of very low-luminosity sources with IR excesses in the Taurus cloud and the Chamaeleon cloud core regions whose extinction corrected J magnitudes are 3 to 8 mag fainter than those of typical T Tauri stars in the same cloud. Some of them are associated with even fainter companions. Follow-up IR spectroscopy has confirmed for the selected sources that their photospheric temperature is around 2000 to 3000 K. Thus, these very low-luminosity young stellar sources are most likely very low-mass T Tauri stars, and some of them might even be young brown dwarfs.

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17

Chevalier, Roger A. "Compact Objects in Supernova Remnants." International Astronomical Union Colloquium 145 (1996): 399–406. http://dx.doi.org/10.1017/s0252921100008253.

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Core collapse in very massive stars can lead to a central black hole that swallows the rest of the star and in less massive stars to a central neutron star and explosion. There is probably an intermediate mass range that gives an explosion and a central black hole; supernova remnants with no observable central object are candidates. The association of pulsars with Type II supernovae gives an estimate of the pulsar power to be expected in a supernova, but the uncertainty in the initial pulsar periods gives a wide range in possible powers. The relativistic wind bubble model for the Crab Nebula has steadily developed and there are now predictions regarding particle acceleration in the optical wisps. The bubble model with expansion into supernova gas can also be applied to other young pulsar nebulae.

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18

KIM, Jinho. "Black Hole, Neutron Star and Numerical Relativity." Physics and High Technology 30, no. 6 (June 30, 2021): 7–13. http://dx.doi.org/10.3938/phit.30.017.

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Compact stars, e.g., black holes and neutron stars, are the most energetic objects in astrophysics. These objects are accompanied by extremely strong gravity and a high velocity, which approaches the speed of light. Therefore, compact objects should be dealt with in Einstein’s relativity. This article will briefly introduce a numerical method that will allow us to obtain general solutions in general relativity. Several applications using numerical relativistic simulations will also be presented.

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Jalali, B., F. I. Pelupessy, A. Eckart, S. Portegies Zwart, N. Sabha, A. Borkar, J. Moultaka, K. Mužić, and L. Moser. "Young stellar objects close to Sgr A*." Proceedings of the International Astronomical Union 9, S303 (October 2013): 144–46. http://dx.doi.org/10.1017/s1743921314000404.

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AbstractWe aim at modeling small groups of young stars such as IRS 13N, 0.1 pc away from Sgr A*, which is suggested to contain a few embedded massive young stellar objects. We perform hydrodynamical simulations to follow the evolution of molecular clumps orbiting around a 4 × 106 M⊙ black hole, to constrain the formation and the physical conditions of such groups.We find that the strong compression due to the black hole along the orbital radius vector of clumps evolving on highly eccentric orbits causes the clumps densities to increase to higher than the tidal density of Sgr A* and required for star formation. This suggests that the tidal compression from the black hole could support star formation.Additionally, we speculate that the infrared excess source G2/DSO approaching Sgr A* on a highly eccentric orbit could be associated with a dust enshrouded star that may have been formed recently through the mechanism supported by our models.

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20

KORN, UWE MAXIMILIAN. "Das Werk im Netzwerk : Zur Bearbeitungsgeschichte von Albrecht von Hallers ,,Die Alpen“." Zeitschrift für Germanistik 29, no. 1 (January 1, 2019): 65–84. http://dx.doi.org/10.3726/92164_65.

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Abstract Das Boundary Object ist ein wissenssoziologischer Begriff, den Susan L. Star und James R. Griesemer 1989 prägten und der Objekte beschreibt, die eine interpretative Flexibilität zeigen und von spezifischem Umfang und spezifischer Strukturierung sind. In vorliegendem Aufsatz wird mit Hilfe dieser Begriffsbildung der anhaltende Erfolg der Gedichtsammlung Versuch Schweizerischer Gedichte von Albrecht Haller erklärt und vorgeführt, dass auch die Gedichtsammlung bestimmende Eigenschaften eines Boundary Object trägt. Dabei werden die materiellen Aspekte der Veröffentlichung berücksichtigt und Änderungen im Gattungsumfeld innerhalb der 1740er Jahre beschrieben.Boundary Object is a term taken from the sociology of knowledge and coined by Susan L. Star and James R. Griesemer (1989). It describes physical objects with the properties of ,interpretive flexibility‘ of a specific scale and structure. Employing this concept I explain the success of Albrecht Haller’s poetic collection Versuch Schweizerischer Gedichte. In the paper it is shown that the collection of poems shares the characteristics of a Boundary Object. It takes into account the material aspects of the publications and describes changes in the system of literary genres within the 1740s.

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21

Emerson, J. P. "IRAS and Star Formation in Dark Clouds." Symposium - International Astronomical Union 115 (1987): 19–31. http://dx.doi.org/10.1017/s0074180900094778.

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As a first step in systematically studying star formation in dark clouds we report a search for IRAS Point Source Catalog detections lieing within the boundaries of Southern Dark Clouds in the catalog of Hartley et al. (1986). To aid in further classifying the 1099 objects by their infrared colours the colours of the whole IRAS Point Source Catalog are discussed and plotted, and the regions occupied by various types of objects tabulated. The presence of Cirrus makes it difficult to confidently identify protostellar like objects from IRAS data alone. Nevertheless 247 sources have colours characteristic of objects deeply embedded in the dark clouds and are probably at least young stars of low mass. These sources appear to be located at random positions within the dark cloud volumes and there is no evidence to suggest that formation of low mass stars in this dark cloud sample is externally triggered.

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22

Shu, Frank H., Daniele Galli, Susana Lizano, and Mike J. Cai. "Magnetization, accretion, and outflows in young stellar objects." Proceedings of the International Astronomical Union 3, S243 (May 2007): 249–64. http://dx.doi.org/10.1017/s1743921307009611.

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AbstractWe review the theory of the formation and gravitational collapse of magnetized molecular cloud cores, leading to the birth of T Tauri stars surrounded by quasi-Keplerian disks whose accretion is driven by the magnetorotational instability (MRI). Some loss of magnetic flux during the collapse results typically in a dimensionless mass-to-flux ratio for the star plus disk of λ0≈ 4. Most of the mass ends up in the star, while almost all of the flux and the angular momentum ends up in the disk; therefore, a known mass for the central star implies a computable flux in the surrounding disk. A self-contained theory of the MRI that drives the viscous/resistive spreading in such circumstances then yields the disk radius needed to contain the flux trapped in the disk as a function of the aget. This theory yields analytic predictions of the distributions with distance ϖ from the central star of the surface density Σ(ϖ), the vertical magnetic fieldBz(ϖ), and the (sub-Keplerian) angular rotation rate Ω (ϖ). We discuss the implications of this picture for disk-winds, X-winds, and funnel flows, and we summarize the global situation by giving the energy and angular-momentum budget for the overall problem.

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23

Kontizas, E., S. E. Maravelias, A. Dapergolas, Y. Bellas-Velidis, and M. Kontizas. "Wide Field Star Count Mapping of Large Scale Areas of Star Formation in the Large Magellanic Cloud." Symposium - International Astronomical Union 161 (1994): 516–17. http://dx.doi.org/10.1017/s0074180900047999.

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Star formation in galaxies is a major astrophysical problem which can be investigated in several ways. The distribution and loci of all kinds of young objects, including OB associations, young clusters, HII regions, GMCs, Bok globules, dark clouds, dust lanes, protostars, as well as YSOs detected in NIR and FIR surveys constitute the principal signposts for this investigation. The individual nature of all these objects has been and is still continously studied. However it is also extremely interesting to associate the coexistence of these objects, and their relation to the structure of the parent galaxy. Such studies have been carried out by several investigators and are frequently summarized when star formation processes are examined.

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24

Podsiadlowski, Philipp. "The Structure and Evolution of Thorne-Żytkow Objects." Symposium - International Astronomical Union 165 (1996): 29–41. http://dx.doi.org/10.1017/s0074180900055534.

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Thorne-Żytkow objects (TŻOs) are red supergiants with neutron cores. The energy source in TŻOs with low-mass envelopes (≲8 M⊙) is accretion onto the neutron core, while for TŻOs with massive envelopes (≲14 M⊙) it is nuclear burning via the exotic rp process. TŻOs are expected to form as a result of unstable mass transfer in high-mass X-ray binaries, the direct collision of a neutron star with a massive companion after a supernova or the collision of a neutron star with a low-mass star in a globular cluster. We estimate a birth rate of massive TŻOs in the Galaxy of ∼2 10−4 yr−1. Thus, for a characteristic TŻO lifetime of 105–106 yr there should be 20–200 TŻOs in the Galaxy at present. These can be distinguished from ordinary red supergiants because of anomalously high surface abundances of lithium and rp-process elements, produced in the TŻO interior. The TŻO phase ends when either the star has exhausted its rp-process seed elements or the envelope mass decreases below a critical mass (∼14 M⊙). Then nuclear burning becomes inefficient and a neutrino runaway ensues, leading to the dynamical accretion of matter near the core onto the neutron star and its spin up to spin frequencies of up to ∼100 Hz. The fate of the massive envelope is not entirely clear. If a significant fraction can be accreted onto the core, the formation of a black hole becomes likely. Part of the envelope may collapse into a massive disk which may ultimately become gravitationally unstable and lead to the formation of planets or even low-mass stars. We discuss the various possible outcomes and suggest a possible link between massive TŻOs and soft X-ray transients.

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25

Paulucci, Laura, Jorge E. Horvath, and Omar Benvenuto. "Nucleosynthesis in Strange Star Mergers." International Journal of Modern Physics: Conference Series 45 (January 2017): 1760042. http://dx.doi.org/10.1142/s2010194517600424.

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The possible existence of deconfined matter in the cores of neutron stars has been studied for over three decades without a firm indication either for or against this proposition. Analysis mostly rely on the comparison of mass-radius curves obtained for different compositions with observational data on the mass of the most massive objects of this kind accurately determined. Nevertheless, there are other possibilities for indirectly studying the internal composition of this class of compact objects, e.g, analyzing cooling behavior, X-ray bursts, supernova’s neutrinos. We present calculations on the expected nucleosynthesis spectra for the strange star-strange star merger scenario as means to test the strange quark matter hypothesis and its realization inside such objects. This would result very different from the typical r-process nucleosynthesis expected in neutron star mergers since the high temperature deconfinement of strange matter would produce large amounts of neutrons and protons and the mass buildup would proceed in a Big-Bang nucleosynthesis like scenario. The neutron to proton ratio would allow to reach the iron peak only, a very different prediction from the standard scenario. The resultant light curve indicate it may be compatible with that of a kilonova depending on the specific details of the ejecta.

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Kömpe, C., T. Lehmann, J. Gürtler, B. Stecklum, and E. Krügel. "Mid-infrared imaging of post-AGB objects." Symposium - International Astronomical Union 180 (1997): 352. http://dx.doi.org/10.1017/s0074180900131274.

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The evolution of low- and intermediate-mass stars (about 1 to 8 M⊙) from the asymptotic giant branch (AGB) to the planetary nebulae stage is characterized by intense stellar wind. AGB stars evolve on a very short time scale (several thousand years) via a phase, where the star is hidden from view by a dense dust shell, towards the post-AGB phase (an optically visible star surrounded by a cold dust/gas shell). The observational investigation of these shells is rather difficult due to their small angular extent. However, the resolution of current infrared telescopes is sufficient to resolve the warm dust of the inner part of the envelope.

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27

Harnden, F. R. "Einstein Observatory Limits on Neutron Star Surface Temperatures." Symposium - International Astronomical Union 125 (1987): 457. http://dx.doi.org/10.1017/s0074180900161194.

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For years the theoretical models of neutron star formation and evolution had remained largely unconstrained by observation. Following the Einstein X-ray Observatory surveys of supernova remnants and pulsars, however, strict temperature limits were placed on many putative neutron stars. The Einstein search for additional objects in the class of supernova remnants with embedded pulsars has increased the number of such objects by two. For the four objects in this class, the surface temperature limits (see Table 1) provide meaningful logically sound constraints on the neutron star models. For the future, however, still better X-ray observations are needed, both to increase the number of objects available for study and to refine the spatial and spectral capabilities of the X-ray measurements.

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28

Conneller, Chantal. "Becoming deer. Corporeal transformations at Star Carr." Archaeological Dialogues 11, no. 1 (June 2004): 37–56. http://dx.doi.org/10.1017/s1380203804001357.

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This article examines the role of red deer antler ‘masks’ recovered from the Early Mesolithic site of Star Carr in northern England. It explores the agency of animals and the type of agency attributable to objects made from parts of animals at the site. When humans use or wear objects that are made from animal parts, I argue that there are also important implications for the way in which the human body is conceived. This article goes on to explore the types of body produced from the taking on of objects made from animal remains and the implications that this has for the ways both humans and animals were perceived during the Mesolithic.

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Lucas, P. W., and P. F. Roche. "Butterfly star in Taurus: structures of young stellar objects." Monthly Notices of the Royal Astronomical Society 286, no. 4 (April 21, 1997): 895–919. http://dx.doi.org/10.1093/mnras/286.4.895.

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Kiczek, Bartłomiej, and Marek Rogatko. "Ultra-compact spherically symmetric dark matter charged star objects." Journal of Cosmology and Astroparticle Physics 2019, no. 09 (September 24, 2019): 049. http://dx.doi.org/10.1088/1475-7516/2019/09/049.

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31

Fellhauer, M. "Dwarf-galaxy-objects formed out of merging star-clusters." Astronomical & Astrophysical Transactions 20, no. 1 (June 2001): 85–88. http://dx.doi.org/10.1080/10556790108208190.

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32

Barabás, Béla, and Ottilia Fülöp. "Star graph representations of chiral objects in graph theory." Journal of Mathematical Chemistry 50, no. 6 (March 15, 2012): 1514–20. http://dx.doi.org/10.1007/s10910-012-9986-9.

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Fülöp, Ottilia, and Béla Barabás. "Three-dimensional chiral objects and their star graph representations." Journal of Mathematical Chemistry 51, no. 9 (August 6, 2013): 2354–60. http://dx.doi.org/10.1007/s10910-013-0215-y.

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34

Hanami, Hitoshi, and T. Tajima. "MHD Reconnection Model for Optical Jets, H-H Objects and GGD Objects." Symposium - International Astronomical Union 140 (1990): 341–42. http://dx.doi.org/10.1017/s0074180900190448.

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Many objects have been observed that are excited by shocks, but nevertheless do not form a shell shape in a variety of astrophysical environments such as in protostellar and circumstellar medium or as seen in optical jets, H-H objects, and GGD objects. The models for these objects, which have been proposed for explaining observed spectrum, can be divided to two types. First one is the cloudlets interaction model (e.g., Schwartz 1978; Norman and Silk 1979; Raga, Böhm, and Solf 1986). Second one is the radiative jet model in which the knotty structure associated in some H-H objects can be suggested as the shock of Mach disks in “underexpanded” jets (e.g., Mundt 1985; Hartigan 1989). However, the wiggles and the irregular knots have been observed in some H-H objects (e.g., knots; HH33, HH40, and wiggles; HH12, HH7-11), which could not be explained well by the two models above. On the other hand, from the observations for maser emissions in star forming regions, the strong magnetic field is inferred(e.g., Fiebig and Gusten 1989). The magnetic field seems to be important for the dynamical motion in star forming regions. Then, a magnetohydrodynamical reconnection model for these phenomena is investigated. We consider the interaction between dense magnetized cloudlet and wind from the central star, through an 2-D MHD code with the MacCormack-Doner cell hybrid scheme to well represent shock phenomena as well as advective phenomena. The density contours and magnetic field lines of numerical results for γ=5/3 and 1.1 are shown in figure (a) and (b), respectively. We present two case for γ=5/3 and 1.1. Results show that the compression effects related to the adiabatic indexes γ are important in the shocked region. The interaction between the cloudlet and wind induces the bow shock around the cloudlet and elongated magnetic structure in the downstream direction, which is similar between two cases. However, the downstream flow patterns behind the cloudlet are different for each other. For γ=1.1, we have a jet-like structure in downstream region. This is induced by magnetic reconnection with strong compressed effects which produces secondary plasma acceleration. This magnetic reconnection is fast (Patscheck) type, which have been well studied for the model of the earth magne-tospheric substorm, related to the slow shock formation and the strong plasma jet generation (e.g. Sato and Hayashi 1979). Furthermore, these behavior is similar to the disconnection events of comets (Alfvén 1957, Niedner 1980), which suggests us the knots in HH objects can be explained as some separated reconnection points in which the magnetic energy is released explosively. For real interstellar medium, γ=5/3, however, we must consider the effect of radiative cooling (Spitzer 1978). This cooling seems to be important for outflows in the star forming regions (Hanami and Sakashita, 1987) Then, we can interpret the compression effect with small γ as that of the cooling, approximately. This compression mechanism related to the cooling effect in interstellar and magnetic reconnections are important for interpreting the formation, and the structure, and the dynamics of optical jets, H-H objects, and GGD objects.

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35

MIGLIARI, SIMONE, GABRIELE GHISELLINI, JAMES MILLER-JONES, and DAVID RUSSELL. "JET MODELS FOR NEUTRON STAR X-RAY BINARIES." International Journal of Modern Physics: Conference Series 08 (January 2012): 108–13. http://dx.doi.org/10.1142/s2010194512004485.

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A variety of different models for jet formation have been developed over the years (mainly) for black hole systems and young stellar objects. Conclusive observational constraints which would favor one particular mechanism are difficult to obtain. Neutron star X-ray binaries are crucial for advancing our understanding of jet formation in general, building a bridge between the two most studied jet-producing classes of systems: black holes, i.e. non-magnetized, relativistic objects, and young stellar objects, i.e. non-relativistic, magnetized stars. I will briefly review the status of our observational knowledge of jets in neutron star X-ray binaries, with a focus on the parameters which might be involved in the production of jets. I will present recent works and current observational programs aiming to quantify the role of the compact object in the formation of jets in neutron star systems. Finally, I will test a jet model developed for young stellar objects, the X–wind model, on a neutron star system.

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36

Szczerba, Ryszard, Bosco H. K. Yung, Marta Sewiło, Natasza Siódmiak, and Agata Karska. "AGB and post-AGB objects in the outer Galaxy." Proceedings of the International Astronomical Union 12, S323 (October 2016): 369–70. http://dx.doi.org/10.1017/s1743921317000515.

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AbstractWe present the results of our search for low- and intermediate mass evolved stars in the outer Galaxy using AllWISE catalogue photometry. We show that the [3.4]−[12] vs. [4.6]−[22] colour-colour diagram is most suitable for separating C-rich/O-rich AGB and post-AGB star candidates. We are able to select 2,510 AGB and 24,821 post-AGB star candidates. However, the latter are severely mixed with the known young stellar objects in this diagram.

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Kurtz, Stan. "Massive Star Formation Throughout the Galactic Disk." Proceedings of the International Astronomical Union 5, H15 (November 2009): 798. http://dx.doi.org/10.1017/s1743921310011762.

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AbstractHigh-mass star formation is manifestly a phenomenon of the Galactic Plane. The process begins with pre-stellar cores, evolves to proto-stellar objects, and culminates in massive main-sequence stars. Because massive young stellar objects are deeply embedded, the radio, sub-mm, and far/mid-infrared spectral windows are the most revealing. Galactic plane surveys at these wavelengths trace hot and cold molecular gas, interstellar masers, warm dust, and ionized gas that are present during star formation.

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Mao, Minnie Y., Ray P. Norris, Rob Sharp, and Jim E. J. Lovell. "PRONGS: Powerful Radio Objects Nested in Galaxies with Star Formation." Proceedings of the International Astronomical Union 5, S267 (August 2009): 119. http://dx.doi.org/10.1017/s1743921310005806.

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AbstractWe have identified a new class of object that we term PRONGS (powerful radio objects nested in galaxies with star formation). These are powerful radio sources whose optical properties are that of spiral/star-forming galaxies, unlike classic powerful radio sources which are typically hosted by elliptical galaxies in the local Universe. Here we present a first look at these enigmatic sources.

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39

Low, F. J. "An Infrared Search for Substellar Objects." Symposium - International Astronomical Union 117 (1987): 427–34. http://dx.doi.org/10.1017/s0074180900150661.

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Preliminary results from a systematic search for nearby substellar objects in the IRAS data bases has revealed only a single candidate among the 12 μm sources in the region of the polar caps. This object appears to be a distant carbon star. All 5700 sources were positionally associated with stars or galaxies.

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Kitsionas, Spyridon, Anthony P. Whitworth, and Ralf S. Klessen. "SPH simulations of star/planet formation triggered by cloud-cloud collisions." Proceedings of the International Astronomical Union 3, S249 (October 2007): 271–78. http://dx.doi.org/10.1017/s1743921308016694.

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AbstractWe present results of hydrodynamic simulations of star formation triggered by cloud-cloud collisions. During the early stages of star formation, low-mass objects form by gravitational instabilities in protostellar discs. A number of these low-mass objects are in the sub-stellar mass range, including a few objects of planetary mass. The disc instabilities that lead to the formation of low-mass objects in our simulations are the product of disc-disc interactions and/or interactions between the discs and their surrounding gas.

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41

Sokolov, V. V., A. I. Kopylov, V. G. Kurt, and S. V. Zharykov. "Deep Search for Optical Counterparts of Gamma-ray Bursters." International Astronomical Union Colloquium 151 (1995): 389–92. http://dx.doi.org/10.1017/s0252921100035417.

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AbstractPreliminary results are presented of the first (searching) stage of our observational program of the search and study of weak blue star-like objects in the two small γ-ray burst boxes GB 790418 and GB 790613. The basic search purposes are (1) the selection of star-like objects weaker than 23m inside these boxes, (2) the selection of the bluest ones in B — V among these objects. The first result is the fact that there are no blue (with B — V < 0) star-like objects brighter than 24m in both boxes. But in each of these GRB error boxes one blue object with smaller flux was selected for further study to elucidate their nature. In the smallest of the archival GRB error boxes (GB 790613) obtained by three satellite triangulation, the bluest star-like object with V = 24.56(±0.16) and B — V = −0.20(±0.19) is near the center (at the distance < 10") of the GRB box. In the GB 790418 error box, the bluest star-like object with B = 24.40(±0.20), B — V = −0.40(±0.40) is found at ≈50" from the center.

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42

Álvarez-Álvarez, Mar, Ángeles I. Díaz, and Marcelo Castellanos. "Massive star population in circumnuclear star-forming regions." Symposium - International Astronomical Union 212 (2003): 537–38. http://dx.doi.org/10.1017/s0074180900212746.

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Due to their high luminosity, the importance of understanding the massive star formation and evolution of giant Hii regions has become more and more evident in the last few years. A mayor scenario where giant H ii regions form and develop are the very inner parts of some galaxies. These bursts frequently are arranged in a ring-like pattern. We present a study of the stellar populations and gas physical conditions in circumnuclear star-forming regions (CNSFR) based on broad- and narrow-band photometry and spectrophotometric data, which have been analyzed with the use of evolutionary population synthesis and photo-ionization models. It is found that most CNSFRs show composite stellar populations of slightly different ages. They seem to have the highest abundances found in H ii region-like objects, showing also N/O overabundances and S/O underabundaces by a factor of about three. Also, CNSFRs as a class segregate from the disk H ii region family, clustering around higher ionizing temperatures.

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43

Di Fazio, A. "A New Theory of Star Formation: Analytical Mass Function and Star Formation Rate." Symposium - International Astronomical Union 115 (1987): 442–43. http://dx.doi.org/10.1017/s0074180900096182.

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An analytical, theoretical, time-dependent initial mass function is derived for the objects created in the fragmentation of a gravitationally unstable gas protocloud. The mass spectrum depends on the chemical-dynamical-radiative evolution of the protocloud and it peaks at a mass slightly greater than the minimum Jeans mass attained throughout the evolution. A fragmentation rate mass spectrum is also analytically derived.

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44

Shao, Michael. "Using SIM for Double Star Astronomy." Proceedings of the International Astronomical Union 2, S240 (August 2006): 54–58. http://dx.doi.org/10.1017/s1743921307003791.

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AbstractThe SIM (Planet Quest) mission is a space-based long-baseline stellar interferometer designed for ultra-precise astrometry. This paper describes how SIM can be used for double star research. There are several regimes of operation. For binary stars separated by more than 1″.5, SIM treats these as distinct objects. Double stars less than ∼10 milliarcsec in separation are seen as a single object and SIM measures the photocenter of the composite object. Between 10 mas and 1″.15, SIM is able to see the double star as two distinct objects, but because photons from both stars are detected there is the possibility of increased noise and measurement bias. This paper describes how double stars are observed with SIM and what information can be derived.

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Lemos, José P. S., and Oleg B. Zaslavskii. "Compact objects in general relativity: From Buchdahl stars to quasiblack holes." International Journal of Modern Physics D 29, no. 11 (July 30, 2020): 2041019. http://dx.doi.org/10.1142/s0218271820410199.

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A Buchdahl star is a highly compact star for which the boundary radius [Formula: see text] obeys [Formula: see text], where [Formula: see text] is the gravitational radius of the star itself. A quasiblack hole is a maximum compact star, or more generically a maximum compact object, for which the boundary radius [Formula: see text] obeys [Formula: see text]. Quasiblack holes are objects on the verge of becoming black holes. Continued gravitational collapse ends in black holes and has to be handled with the Oppenheimer–Snyder formalism. Quasistatic contraction ends in a quasiblack hole and should be treated with appropriate techniques. Quasiblack holes, not black holes, are the real descendants of Mitchell and Laplace dark stars. Quasiblack holes have many interesting properties. We develop the concept of a quasiblack hole, give several examples of such an object, define what it is, draw its Carter–Penrose diagram, study its pressure properties, obtain its mass formula, derive the entropy of a nonextremal quasiblack hole and through an extremal quasiblack hole give a solution to the puzzling entropy of extremal black holes.

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46

Richards, Anita M. S. "Masers in evolved star winds." Proceedings of the International Astronomical Union 8, S287 (January 2012): 199–208. http://dx.doi.org/10.1017/s1743921312006977.

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AbstractThis review summarises current observations of masers around evolved stars and models for their location and behaviour, followed by some of the many highlights from the past 5 years. Some of these have been the fruition of long-term monitoring, a vital aspect of study of stars which are both periodically variable and prone to rapid outbursts or transition to a new evolutionary stage. Interferometric imaging of masers provide the highest-resolution probes of the stellar wind, but their exponential amplification and variability means that multiple observations are needed to investigate questions such as what drives the wind from the stellar surface; why does it accelerate slowly over many tens of stellar radii; what causes maser variability. VLBI parallaxes have improved our understanding of individual objects and of Galactic populations. Masers from wide range of binary and post-AGB objects are accessible to sensitive modern instruments, including energetic symbiotic systems. Masers have been detected up to THz frequencies withHerscheland ALMA's ability to resolve a wide range of maser and thermal lines will provide accurate constraints on physical conditions including during dust formation.

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Sharif, M., and Arfa Waseem. "Charged compact objects in f(R,T) gravity." International Journal of Modern Physics D 28, no. 02 (January 2019): 1950033. http://dx.doi.org/10.1142/s0218271819500330.

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This paper analyzes the effects of charge on the nature of relativistic compact star candidates with anisotropic distribution in the framework of [Formula: see text] gravity. For this purpose, we consider Krori–Barua solutions and obtain the values of unknown constants as well as charge using observational data of Her X-1, 4U1820-30 and SAX J 1808.4-3658 star models. For three viable [Formula: see text] models, we investigate the behavior of energy density, transverse as well as radial pressures in the interior geometry of these stars. The validity of energy conditions, effect of anisotropic factor and stability of these stellar models are also examined. We conclude that the effect of charge leads to more stable structures of relativistic compact objects.

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48

Roberts, Ann R. "Catch a star in your net." Early Years Educator 21, no. 2 (June 2, 2019): x—xi. http://dx.doi.org/10.12968/eyed.2019.21.2.x.

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Nets are a cheap, readily available, versatile resource. Use them to make dens, catch carboard stars and all sorts of other objects. Talk about how they keep us safe and have fun crawling beneath them.

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49

Valtier, J. C., J. M. Le Contel, P. Antonelli, P. Michel, and J. P. Sareyan. "A Four Star Photometer." International Astronomical Union Colloquium 136 (1993): 179–86. http://dx.doi.org/10.1017/s0252921100007545.

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AbstractA new photometer is presently being developed at the O.C.A. Observatory. It consists of four arms and a CCD camera situated in the focal plane of the telescope. Each arm can move in both directions and support a diaphragm and a liquid optic guide that directs the light to a photomultiplier. The simultaneous acquisition of the four signals enables to obtain magnitude differences between the objects in real time. A typical use of this photometer is to observe at the same time one or two variables, comparison stars and the sky background.

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50

A Norman, Colin. "Star Formation at High Redshift." Australian Journal of Physics 45, no. 4 (1992): 389. http://dx.doi.org/10.1071/ph920389.

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The observations relevant to star formation at high redshift are reviewed including radio galaxies, quasars, IRAS objects, and QSO emission and absorption line regions. Low redshift counterparts associated with starburst galaxies are discussed. The relation of galaxy formation, starbursts, and active galaxies and quasars is briefly reviewed. The role of feedback in galaxy formation and massive star formation is briefly analysed.

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