Articoli di riviste: "Primeval galaxies"

1

Miley, George. "Primeval galaxies". Physics World 2, n. 10 (ottobre 1989): 35–38. http://dx.doi.org/10.1088/2058-7058/2/10/22.

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2

Cowen, Ron. "Found: Primeval Galaxies". Science News 149, n. 8 (24 febbraio 1996): 120. http://dx.doi.org/10.2307/3979806.

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3

OZERNOY, LEONID M. "Primeval and "Rejuvenated" Galaxies." Annals of the New York Academy of Sciences 571, n. 1 Texas Symposi (dicembre 1989): 219–27. http://dx.doi.org/10.1111/j.1749-6632.1989.tb50509.x.

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4

Collins, C. A. "Searches for primeval galaxies". Contemporary Physics 40, n. 1 (gennaio 1999): 1–10. http://dx.doi.org/10.1080/001075199181675.

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5

Wada, Keiichi, e Asao Habe. "Primeval starburst and bulge formation". Symposium - International Astronomical Union 153 (1993): 397–98. http://dx.doi.org/10.1017/s0074180900123769.

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6

Pritchet, C. J. "The search for primeval galaxies". Publications of the Astronomical Society of the Pacific 106 (ottobre 1994): 1052. http://dx.doi.org/10.1086/133479.

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7

Mori, Masao, e Masayuki Umemura. "Galactic winds from primeval galaxies". Astrophysics and Space Science 311, n. 1-3 (8 giugno 2007): 111–15. http://dx.doi.org/10.1007/s10509-007-9533-5.

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8

Baron, E., e Simon D. M. White. "The appearance of primeval galaxies". Astrophysical Journal 322 (novembre 1987): 585. http://dx.doi.org/10.1086/165754.

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9

Collins, C. A., e R. D. Joseph. "An infrared search for primeval galaxies". Monthly Notices of the Royal Astronomical Society 235, n. 1 (1 novembre 1988): 209–20. http://dx.doi.org/10.1093/mnras/235.1.209.

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10

Derobertis, M. M., e Marshall L. McCall. "A Continuum Search for Primeval Galaxies". Astronomical Journal 109 (maggio 1995): 1947. http://dx.doi.org/10.1086/117420.

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11

Silk, Joseph, e Alexander S. Szalay. "Primeval galaxies and cold dark matter". Astrophysical Journal 323 (dicembre 1987): L107. http://dx.doi.org/10.1086/185067.

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12

McCall, Marshall L., e Michael M. Derobertis. "Searching the Continuum for Primeval Galaxies". Symposium - International Astronomical Union 171 (1996): 417. http://dx.doi.org/10.1017/s0074180900233366.

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A population of primeval galaxies (PG's) should be detectable by directly imaging with two intermediate-band filters tuned to either side of the Lyman break (DeRobertis, M. M., and McCall, M. L. 1995, A.J., 109, 1947). In the figure below, the solid and short-dashed curves show the flux (left scale) as a function of redshift from a PG 0.7 Gyr old with a total stellar mass of as seen through filters with rest-frame passbands 890 ± 30 Å (‘β’) and 1010 ± 30 Å (‘ρ’), respectively, moved to redshift 5. The upper curves depict the colour β – ρ (right scale); the dotted line is for the 0.7 Gyr population, and the dot-dashed line is for a 7.5 Gyr model. A source can be identified as a PG if it can be clearly detected in the ρ filter and if it has a colour greater than +0.75 mag. Confusion with any old stellar systems at lower redshifts can be eliminated by supplementing observations with Gunn r and i. The colour condition selects Lyman break objects between redshifts 4.7 and 5.4, a range over an order of magnitude greater than is achievable through an emission line survey. The discriminatory power of the technique is not affected by internal dust.

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13

Thommes, E., e K. Meisenheimer. "Number Density Predictions for Primeval Galaxies". Symposium - International Astronomical Union 171 (1996): 454. http://dx.doi.org/10.1017/s007418090023372x.

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In the last two decades several methods have been employed to search for the ancestors of present day galaxies undergoing their first starburst at high redshift, the so-called “primeval galaxies” (PGs). According to predictions of the Ly-α flux from the PG phase current surveys for Ly-α bright PGs should have detected 101 − 103 PGs. Yet, no really good candidate has been found. One possible explanation for this discrepancy would be the presence of dust which could strongly suppress Ly-α. In fact, models of early galaxy formation are able to produce gas to dust ratios of about 1/10 solar after some 108 years. This would suppress the emerging Ly-α flux below current detection limits. Thus, to detect a PG in its Ly-α bright phase, one has to hit exactly the redshift of their first star formation. On the other hand, the epoch of galaxy formation is likely to extend over much longer time. So when searching a finite volume of the universe (given by the depth Δz and the field ΔΩ), the protogalaxies are not simultaniously in the Ly-α bright PG phase and only a fraction of them exceed the detection limit. Our new attempt to predict the expected number of PGs takes this reduced propability into account. Further contraints of the Ly-α luminosity were derived from recent observations and theoretical work (for details see E.Thommes & K.Meisenheimer in Galaxies in the Young Universe, Eds. H.Hippelein et al., Springer-Verlag, 1995, p.242). As expected, we find that the number density of Ly-α emitting PGs is drastically reduced in comparison to previous predictions. Thus previous surveys had no realistic chance to find them. Nevertheless, our calculations also show, that the detection of Ly-α bright PGs is in the scope of present day techniques. Specifically, we predict that the Calar-Alto-Deep-Imaging-Survey (see contribution of H. Hippelein et. al., these proc.) which will search for Ly-α in an area of ≈ 0.3□° down to a limiting line flux of 3 × 10−20W/m2 should detect 10 … 100 PGs in three redshift intervals Δz = 0.1. The uncertainty accounts for our ignorance of q0 and the unknown epoch of galaxy formation.

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14

Pentericci, L., A. Grazian, A. Fontana, M. Castellano, E. Giallongo, S. Salimbeni e P. Santini. "The physical properties of Lyαemitting galaxies: not just primeval galaxies?" Astronomy & Astrophysics 494, n. 2 (4 dicembre 2008): 553–61. http://dx.doi.org/10.1051/0004-6361:200810722.

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15

Thompson, D., e S. G. Djorgovski. "Serendipitous Long-Slit Surveys for Primeval Galaxies". Astronomical Journal 110 (settembre 1995): 982. http://dx.doi.org/10.1086/117577.

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16

Sofue, Yoshiaki. "Vertical Magnetic Fields in Spiral Galaxies". Symposium - International Astronomical Union 140 (1990): 227–32. http://dx.doi.org/10.1017/s0074180900190060.

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Evolution of a vertical magnetic field which may have existed in the primeval galaxy is discussed based on a primordial-origin hypothesis for the bisymmetric spiral configuration of magnetic fields in spiral galaxies. The vertical field is accumulated toward the nucleus and forms a strong poloidal field, which may trigger activities like jets. Quasar jets are suggested to be the result of such strong vertical fields in the cores of primeval galaxies.

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17

Hidalgo, Sebastian L. "Seeking footprints of the primeval Universe in dwarf galaxies". Proceedings of the International Astronomical Union 10, H16 (agosto 2012): 273–74. http://dx.doi.org/10.1017/s1743921314005730.

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AbstractWe present the star formation histories (SFHs) of four isolated dwarf galaxies, Cetus, Tucana, LGS-3, and Phoenix, as a function of galactocentric radius. Our results suggest that beyond some distance from the center, there are no significative differences in fundamental properties of these galaxies, such as the star formation rate (SFR) or age-metallicity relation (AMR). The stellar content of this region would be composed of old (≳ 10.5 Gyr) metal-poor stars only. In the innermost regions, dwarf galaxies appear to have formed stars during time intervals which duration varies from galaxy to galaxy. This extended star formation produces the dichotomy between dwarf spheroidal (dSph) and dwarf Transition (dTr) galaxy types.

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18

Buzzoni, A. "Evolutionary Population Synthesis Models of Primeval Galaxies: A Critical Appraisal". Symposium - International Astronomical Union 183 (1999): 134–39. http://dx.doi.org/10.1017/s0074180900132280.

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A recognized problem when searching for primeval galaxies at cosmological distances is a definition of a firm selection criterion (alternative to a direct but extremely time-demanding measure of z) to single out high-redshift candidates from the plethora of other more or less peculiar objects (i.e. AGN, starburst galaxies etc.) at lower distances.The case of the HST “Deep Field” (HDF) observations (Williams et al. 1996) is especially relevant in this regard as galaxies up to z = 3.2 have been detected in the field (Steidel et al. 1996).

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19

Carniani, Stefano. "ALMA witnesses the assembly of first galaxies". Proceedings of the International Astronomical Union 15, S352 (giugno 2019): 27–32. http://dx.doi.org/10.1017/s1743921319009098.

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AbstractCharacterising primeval galaxies entails the challenging goal of observing galaxies with modest star formation rates (SFR < 100 Mȯyr−1) and approaching the beginning of the reionisation epoch (z > 6). To date a large number of primeval galaxies have been identified thanks to deep near-infrared surveys. However, to further our understanding on the formation and evolution of such primeval objects, we must investigate their nature and physical properties through multi-band spectroscopic observations. Information on dust content, metallicity, interactions with the surrounding environment, and outflows can be obtained with ALMA observations of far-infrared (FIR) lines such as the [Cii] at 158 μm and [Oiii] at 88 μm. Here, we, thus, discuss the recent results unveiled by ALMA observations and present new [Cii] observations of BDF-3299, a star-forming galaxy at z = 7.1 showing a spatial and spectral offset between the rest-frame UV and the FIR lines emission.

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20

Thommes, E., e K. Meisenheimer. "The expected abundance of Lyman-αemitting primeval galaxies". Astronomy & Astrophysics 430, n. 3 (26 gennaio 2005): 877–91. http://dx.doi.org/10.1051/0004-6361:20035863.

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21

Thompson, D., S. Djorgovski e S. V. W. Beckwith. "Searches for primeval galaxies in the near infrared". Astronomical Journal 107 (gennaio 1994): 1. http://dx.doi.org/10.1086/116830.

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22

Thompson, D., S. Djorgovski e J. Trauger. "A Narrow Band Imaging Survey for Primeval Galaxies". Astronomical Journal 110 (settembre 1995): 963. http://dx.doi.org/10.1086/117576.

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23

Pritchet, C. J., e F. D. A. Hartwick. "A search for primeval galaxies at Z = 1.9". Astrophysical Journal 355 (maggio 1990): L11. http://dx.doi.org/10.1086/185726.

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24

Kronberg, Philipp P., Harald Lesch e Ulrich Hopp. "Magnetization of the Intergalactic Medium by Primeval Galaxies". Astrophysical Journal 511, n. 1 (20 gennaio 1999): 56–64. http://dx.doi.org/10.1086/306662.

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25

Hippelein, H., K. Meisenheimer, E. Thommes, R. Fockenbrock e H. J. Röser. "Search for Primeval Galaxies with the “Calar Alto Deep Imaging Survey”". Symposium - International Astronomical Union 171 (1996): 287–90. http://dx.doi.org/10.1017/s007418090023249x.

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Understanding the formation of galaxies is certainly one of the major challenges in astrophysics. Observationally, the most important insight will be provided by the detection and study of primeval galaxies. With the large telescopes and the efficient detectors available today, it seems feasible to observe those early stages of galaxy evolution directly. Despite considerable efforts with different techniques (Cowie et al. 1990; De Propris et al. 1993; Pritchet & Hartwick 1990; Thompson et al. 1995; Djorgovski et al. 1993) no primeval galaxy is found yet, in contradiction with predictions by model calculations (e.g. Baron & White 1987). What could be the reason for this lack of sucess?

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26

Plat, A., S. Charlot, G. Bruzual, A. Feltre, A. Vidal-Garca, C. Morisset e J. Chevallard. "Constraints on the production and escape of ionizing radiation from the emission-lines of metal-poor star-forming galaxies". Proceedings of the International Astronomical Union 15, S352 (giugno 2019): 121–22. http://dx.doi.org/10.1017/s1743921319009347.

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AbstractTo understand how the nature of the ionizing sources and the leakage of ionizing photons in high-redshift galaxies can be constrained from their emission-line spectra, we compare emission-line models of star-forming galaxies including leakage of ionizing radiation, active galactic nuclei (AGN) and radiative shocks, with observations of galaxies at various redshifts with properties expected to approach those of primeval galaxies.

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27

Calzetti, D., e A. L. Kinney. "Lyman-alpha emission in star-forming galaxies - Low-redshift counterparts of primeval galaxies?" Astrophysical Journal 399 (novembre 1992): L39. http://dx.doi.org/10.1086/186601.

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28

Riaz, Shafqat, Tilman Hartwig e Muhammad A. Latif. "Unveiling the Contribution of Population III Stars in Primeval Galaxies at Redshift ≥6". Astrophysical Journal Letters 937, n. 1 (1 settembre 2022): L6. http://dx.doi.org/10.3847/2041-8213/ac8ea6.

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Abstract Detection of the first stars has remained elusive so far but their presence may soon be unveiled by upcoming JWST observations. Previous studies have not investigated the entire possible range of halo masses and redshifts that may help in their detection. Motivated by the prospects of detecting galaxies up to z ∼ 20 in the JWST early data release, we quantify the contribution of Population III stars to high-redshift galaxies from 6 ≤ z ≤ 30 by employing the semianalytical model a-sloth, which self-consistently models the formation of Population III and Population II stars along with their feedback. Our results suggest that the contribution of Population III stars is the highest in low-mass halos of 107–109 M ⊙. While high-mass halos ≥1010 M ⊙ contain less than 1% Population III stars, they host galaxies with stellar masses of 109 M ⊙ as early as z ∼ 30. Interestingly, overall the apparent magnitude of Population III stars gets brighter toward higher redshift due to the higher stellar masses, but Population III–dominated galaxies are too faint to be directly detected with JWST. Our results predict JWST can detect galaxies up to z ∼ 30, which may help in constraining the initial mass function of Population III stars and will guide observers to discern the contribution of Population III stars to high-redshift galaxies.

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29

Brown, Thomas M., Jason Tumlinson, Marla Geha, Evan N. Kirby, Don A. VandenBerg, Ricardo R. Muñoz, Jason S. Kalirai et al. "THE PRIMEVAL POPULATIONS OF THE ULTRA-FAINT DWARF GALAXIES". Astrophysical Journal 753, n. 1 (15 giugno 2012): L21. http://dx.doi.org/10.1088/2041-8205/753/1/l21.

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30

Matsumoto, Toshio. "Infrared Extragalactic Background Light". Symposium - International Astronomical Union 139 (1990): 317–26. http://dx.doi.org/10.1017/s0074180900240874.

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Infrared extragalactic background light plays an important role in the study of the early history of the universe, especially as a probe to search for the primeval galaxies. In the near-infrared region, UV and visible light emitted from high redshift galaxies could be observable. Measurement of the sky fluctuation at 2.2 μm gives a very low upper limit. The rocket observation of the near-infrared diffuse emission reveals isotropic emission which is possibly ascribed to an extragalactic origin. The observed brightness and fluctuation are not consistent with the standard scenario of the primeval galaxies. In the far-infrared region, integrated light of dust emission of the distant galaxies forms another cosmic background radiation. IRAS and the Nagoya-Berkeley rocket experiment found a clear correlation between HI column density and far-infrared sky brightness; however, there remains an uncorrelated isotropic emission component. If we ascribe this emission to extragalactic origin, a fairly big evolution effect is required. In the submillimeter region, excess emission over the 2.74K blackbody spectrum was found, which requires the vast energy generation in the early universe.

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31

Muradian, R. M. "The Primeval Hadron: Origin of Rotation and Magnetic Fields in the Universe". Symposium - International Astronomical Union 121 (1987): 341–45. http://dx.doi.org/10.1017/s0074180900155342.

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The problem of the origin of celestial bodies - stars, galaxies and their clusters - is discussed proceeding from the concept of superheavy strongly interacting elementary particles termed superhadrons.Starting from generalized Regge law the universal relationship between mass and intrinsic angular momentum of cosmic objects has been established. Expressions are obtained for parameters of stars and Universe via fundamental constants. The prediction of the global rotation of the Universe is discussed and the problems of cosmic magnetic fields and energy problem in active galaxies are considered.

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32

Elston, R., M. J. Rieke e G. H. Rieke. "Observations of deep 2 micron survey galaxies - Primeval galaxy candidates". Astrophysical Journal 341 (giugno 1989): 80. http://dx.doi.org/10.1086/167473.

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33

Windhorst, Rogier A., Alan Dressler e David C. Koo. "Ultradeep Optical Identifications and Spectroscopy of Faint Radio Sources". Symposium - International Astronomical Union 124 (1987): 573–76. http://dx.doi.org/10.1017/s0074180900159571.

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During the last two years we have completed an extensive project of direct CCD imaging with the Palomar 200 inch Four-shooter on several milliJansky and microJansky radio samples, now totaling 200 sources. The purpose is to study the nature and redshift distribution of the radio galaxies that cause the upturn in the milliJansky source counts (WMOKK) and to search for candidates of primeval radio galaxies.

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34

Peebles, P. J. E. "Cosmology and Fluctuations in the Radiation Backgrounds". Symposium - International Astronomical Union 139 (1990): 295–306. http://dx.doi.org/10.1017/s0074180900240850.

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Four topics are discussed. First, measurements of the autocorrelation function of the optical extragalactic sky background check the possibility that there is an appreciable contribution from young galaxies or from stars well outside normal galaxies. Second, large-scale fluctuations in the mass distribution are probed by the anisotropies of the X-ray and 2.7 K backgrounds. Third, scattering by plasma in young galaxies could affect the primeval anisotropy of the 2.7 K background radiation. Fourth, production of the heavy elements is expected to yield background radiation with a characteristic and perhaps detectable angular distribution.

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35

Kennicutt, R. C. "Assembling Spiral Galaxies". Symposium - International Astronomical Union 171 (1996): 11–18. http://dx.doi.org/10.1017/s0074180900232099.

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Nearby spiral galaxies offer vital clues to some of the most fundamental questions about galaxy formation and evolution: What is the star formation history of the universe, past and future? When did disks form, during the final stages of a single primeval collapse, or as a continuous or episodic process? What is the evolutionary nature of the Hubble sequence, and what are the physical mechanisms that dictate the present-day Hubble type of a galaxy? Was Hubble type imprinted at birth, or can it be deterined or at least modified by infall, mergers, or secular dynamical evolution within the galaxy? These issues are not specific to spirals, of course, and much of this conference will address just these questions in a broader context. However present-day spirals offer unique advantages for studying these problems; they exhibit a broad range of dynamical and evolutionary properties, and the dynamical fragility of disks makes them excellent seismometers of galaxy interaction and merger rates at recent epochs.

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36

Martinez-Gonzalez, E., J. I. Gonzalez-Serrano, J. L. Sanz, J. M. Martin-Mirones e L. Cayon. "Upper Limits on the LYα Emission at Z = 3.4". Symposium - International Astronomical Union 168 (1996): 497–98. http://dx.doi.org/10.1017/s0074180900110472.

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Many searches have been carried out to detect emission from massive primeval hydrogen clouds at high redshift. By observing the 21 cm line it has been possible to impose strong upper limits on the mass and number of protoclusters at high redshift (Wieringa, et al. 1992). Since strong Lyα emission is expected from primeval galaxies undergoing their first burst of star formation, many attempts to detect this emission have been made, but no positive detection has been reported, imposing strong constraints on models of galaxy formation (see Djorgovski et al. 1993 for a review).

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37

de Propris, R., C. J. Pritchet, F. D. A. Hartwick e P. Hickson. "A search for primeval galaxies using a narrow-band imaging technique". Astronomical Journal 105 (aprile 1993): 1243. http://dx.doi.org/10.1086/116506.

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38

Clements, D. L., S. A. Eales e A. C. Baker. "Candidate high-redshift and primeval galaxies in Hubble Deep Field South". Monthly Notices of the Royal Astronomical Society 308, n. 1 (settembre 1999): L11—L16. http://dx.doi.org/10.1046/j.1365-8711.1999.02883.x.

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39

Mori, Masao, e Masayuki Umemura. "The evolution of galaxies from primeval irregulars to present-day ellipticals". Nature 440, n. 7084 (marzo 2006): 644–47. http://dx.doi.org/10.1038/nature04553.

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40

Buzzoni, Alberto. "Ultraviolet Properties of Primeval Galaxies: Theoretical Models from Stellar Population Synthesis". Astronomical Journal 123, n. 3 (marzo 2002): 1188–99. http://dx.doi.org/10.1086/338896.

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41

Pritchet, C. J., e F. D. A. Hartwick. "A search for primeval galaxies using a narrow-band imaging technique". Astrophysical Journal 320 (settembre 1987): 464. http://dx.doi.org/10.1086/165563.

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42

Thommes, E., K. Meisenheimer, R. Fockenbrock, H. Hippelein e H. J. Röser. "The Calar Alto Deep Imaging Survey: First Results". Symposium - International Astronomical Union 179 (1998): 296–98. http://dx.doi.org/10.1017/s0074180900128839.

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The Calar Alto Deep Imaging Survey (CADIS) is a very deep emission line survey using a Fabry-Pérot (FP), combined with deep broad- and medium-band photometry (for an overview see Hippelein et al. 1996). This survey is specifically designed to detect primeval galaxies, but it will in addition produce a large data base for investigations of faint galaxies at intermediate redshifts (0.2 < z < 1.2). We present some first results from the initial data recorded with the CADIS strategy.

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43

Schaerer, Daniel. "Searching for Pop III stars and galaxies at high redshift". Proceedings of the International Astronomical Union 4, S255 (giugno 2008): 66–74. http://dx.doi.org/10.1017/s1743921308024599.

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AbstractWe review the expected properties of Pop III and very metal-poor starbursts and the behaviour the Lyα and Heiiλ1640 emission lines, which are most likely the best/easiest signatures to single out such objects. Existing claims of Pop III signatures in distant galaxies are critically examined, and the searches for Heiiλ1640 emission at high redshift are summarised. Finally, we briefly summarise ongoing and future deep observations atz> 6 aiming in particular at detecting the sources of cosmic reionisation as well as primeval/Pop III galaxies.

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44

Peebles, P. J. E. "On the History and Present Situation". Proceedings of the International Astronomical Union 14, A30 (agosto 2018): 203–7. http://dx.doi.org/10.1017/s1743921319004083.

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AbstractA common thought in the 1950s was that galaxies rotate because they are remnants of primeval currents, as in turbulence. But this idea is quite unacceptable in an expanding universe described by general relativity theory. Since we are no smarter now than in the 1950s the lesson I draw is that we do well on occasion to pause to consider whether we might be missing something. An example is the pure disk galaxies that are so common nearby and so rare in simulations. We have something to learn from this.

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45

Tonry, John L. "Properties of cD Galaxies". Symposium - International Astronomical Union 127 (1987): 89–98. http://dx.doi.org/10.1017/s0074180900185080.

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cD galaxies are the most luminous galaxies in the universe. They are characterized by a surface brightness profile that falls off more slowly with radius than most elliptical galaxies. In most respects D galaxies are a continuous extrapolation from other ellipticals: their M/L and their colors are comparable to other ellipticals, their inner parts are fitted by an r1/4 law, and they follow the same relation between L and σ. On the other hand, their luminosity is too bright to be consistent with the luminosity function of other ellipticals and they are always found at the center of a cluster of other galaxies. Being at the center of a cluster of galaxies often endows D galaxies with a very faint, very extended halo of luminosity and multiple nuclei, but these are more properly associated with the cluster than the D galaxy itself. The connection between the formation of cD galaxies and the formation of clusters remains a mystery. It is still unresolved whether cDs are a byproduct of cluster evolution, whether they formed in parallel with clusters, or whether primeval D are galaxies the seed around which clusters accreted.

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Gutkin, Julia, Stéphane Charlot e Gustavo Bruzual. "Modelling the nebular emission from primeval to present-day star-forming galaxies". Monthly Notices of the Royal Astronomical Society 462, n. 2 (18 luglio 2016): 1757–74. http://dx.doi.org/10.1093/mnras/stw1716.

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47

Windhorst, Rogier A. "Is the Upturn in the Source Counts Caused by Primeval Radio Galaxies?" Highlights of Astronomy 7 (1986): 355–66. http://dx.doi.org/10.1017/s1539299600006638.

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During the last decade several deep surveys have been made with various aperture synthesis radio telescopes. At milliJansky levels important contributions were made with the WSRT 3 km array and the Cambridge One Mile Telescope. At sub-milliJansky levels surveys have been done with the VLA and the WSRT down to rms noise values of ~10 μJy.

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48

Peebles, P. J. E. "The Primeval Mass Fluctuation Spectrum and the Distribution of the Nearby Galaxies". Astrophysical Journal 473, n. 1 (10 dicembre 1996): 42–56. http://dx.doi.org/10.1086/178125.

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49

Amorin, Ricardo. "Analogs of high redshift galaxies: Disentangling the complexity of the green peas". Proceedings of the International Astronomical Union 15, S352 (giugno 2019): 303. http://dx.doi.org/10.1017/s174392132000126x.

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AbstractYoung low-mass galaxies with extreme emission-line properties are ubiquitous at high redshift. However, a detailed characterisation of their physical properties, key for understanding cosmic reionisation and the early growth of galaxies, will be only possible with JWST and ELT observations. Rare lower-z analogues of these primeval galaxies provide us ideal laboratories to study in larger detail the complex physical mechanisms taking place in these extreme systems. In this talk, I will review key results from these high-z analogues, with an emphasis on lessons learned from deep spectroscopic observations of green pea galaxies at z ⩽ 0.3. New recent results based on high-dispersion Echelle and IFU spectroscopy of green peas will be presented. They illustrate current advantages and limitations of the chemodynamical analysis for a simultaneous study of the ionised gas kinematics, chemical enrichment and the escape of ionising photons in compact low-mass starbursts.

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50

Koo, D. C., R. G. Kron e R. A. Windhorst. "Optical Spectra of Low Flux Radio Sources". Symposium - International Astronomical Union 134 (1989): 518–19. http://dx.doi.org/10.1017/s0074180900141841.

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Low flux radio sources are important for a variety of reasons. In principle, a 1 mJy survey that is over 1000 times fainter than the 3CR allows us to reach objects 20 times more distant, almost literally to the edge of the universe, or to detect much less luminous sources at the same distances. We can hope to detect primeval galaxies, to check the idea that objects with redshifts z greater than 3 or 4 are optically hidden by dust, to detect new populations of radio objects, to possess pointers to distant clusters and galaxies, as well as to understand better the AGN phenomenon.

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