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Academic literature on the topic 'Star masses'

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Published: 10 December 2022
Last updated: 28 January 2023

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Journal articles on the topic "Star masses"

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Nice, David. "Neutron star masses." Proceedings of the International Astronomical Union 8, S291 (August 2012): 146. http://dx.doi.org/10.1017/s1743921312023423.

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AbstractNeutron star masses can be inferred from observations of binary pulsar systems, particularly by the measurement of relativistic phenomena within these orbits. The observed distribution of masses can be used to infer or constrain the equation of state for nuclear matter and to study astrophysical processes such as supernovae and binary star evolution. In this talk, I will review our present understanding of the neutron star mass distribution with an emphasis on the observational data.
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Maddox, John. "Star masses and bayesian probability." Nature 371, no. 6499 (October 1994): 649. http://dx.doi.org/10.1038/371649a0.

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Kruckow, Matthias U. "Masses of double neutron star mergers." Astronomy & Astrophysics 639 (July 2020): A123. http://dx.doi.org/10.1051/0004-6361/202037519.

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Aims. I aim to explain the mass discrepancy between the observed double neutron-star binary population by radio pulsar observations and gravitational-wave observation. Methods. I performed binary population synthesis calculations and compared their results with the radio and the gravitational-wave observations simultaneously. Results. Simulations of binary evolution were used to link different observations of double neutron star binaries with each other. I investigated the progenitor of GW190425 in more detail. A distribution of masses and merger times of the possible progenitors is presented. Conclusions. A mass discrepancy between the radio pulsars in the Milky Way with another neutron star companion and the inferred masses from gravitational-wave observations of those kind of merging systems is naturally found in binary evolution.
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Rocha, Lívia S., Antônio Bernardo, Jorge E. Horvath, Rodolfo Valentim, and Marcio G. B. Avellar. "The distribution of neutron star masses." Astronomische Nachrichten 340, no. 9-10 (November 2019): 957–63. http://dx.doi.org/10.1002/asna.201913743.

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Sbisà, Fulvio, Pedro O. Baqui, Tays Miranda, Sergio E. Jorás, and Oliver F. Piattella. "Neutron star masses in R2-gravity." Physics of the Dark Universe 27 (January 2020): 100411. http://dx.doi.org/10.1016/j.dark.2019.100411.

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Waltham, David. "Star Masses and Star-Planet Distances for Earth-like Habitability." Astrobiology 17, no. 1 (January 2017): 61–77. http://dx.doi.org/10.1089/ast.2016.1518.

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Neumayer, Nadine. "Nuclear Star Clusters." Proceedings of the International Astronomical Union 12, S316 (August 2015): 84–90. http://dx.doi.org/10.1017/s1743921316007018.

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AbstractThe centers of galaxies host two distinct, compact components: massive black holes and nuclear star clusters. Nuclear star clusters are the densest stellar systems in the universe, with masses of ~ 107M⊙and sizes of ~ 5pc. They are almost ubiquitous at the centres of nearby galaxies with masses similar to, or lower than the Milky Way. Their occurrence both in spirals and dwarf elliptical galaxies appears to be a strong function of total galaxy light or mass. Nucleation fractions are up to 100% for total galaxy magnitudes of MB= −19mag or total galaxy luminosities of about LB= 1010L⊙and falling nucleation fractions for both smaller and higher galaxy masses. Although nuclear star clusters are so common, their formation mechanisms are still under debate. The two main formation scenarios proposed are the infall and subsequent merging of star clusters and the in-situ formation of stars at the center of a galaxy. Here, I review the state-of-the-art of nuclear star cluster observations concerning their structure, stellar populations and kinematics. These observations are used to constrain the proposed formation scenarios for nuclear star clusters. Constraints from observations show, that likely both cluster infall and in-situ star formation are at work. The relative importance of these two mechanisms is still subject of investigation.
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Hensler, Gerhard, Patrick Steyrleithner, and Simone Recchi. "Star formation at low rates - the impact of lacking massive stars on stellar feedback." Proceedings of the International Astronomical Union 11, S321 (March 2016): 99–101. http://dx.doi.org/10.1017/s1743921316011261.

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AbstractDue to their low masses dwarf galaxies experience low star-formation rates resulting in stellar cluster masses insufficient to fill the initial mass function (IMF) to the uppermost mass. Numerical simulations usually do not account for the completeness of the IMF, but treat a filed IMF by numbers, masses, and stellar feedback by fractions. To ensure that only entire stars are formed, we consider an IMF filled from the lower-mass regime and truncated where at least one entire massive star is formed.By 3D simulations we investigate the effects of two possible IMFs on the evolution of dwarf galaxies: filled vs. truncated IMF. For the truncated IMF the star-formation self-regulation is suppressed, while the energy release by typeII supernovae is larger, both compared to the filled IMF. Moreover, the abundance ratios of particular elements yielded from massive and intermediate-mass stars differ significantly between the two IMF distributions.
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Fahrion, K., M. Lyubenova, G. van de Ven, M. Hilker, R. Leaman, J. Falcón-Barroso, A. Bittner, et al. "Diversity of nuclear star cluster formation mechanisms revealed by their star formation histories." Astronomy & Astrophysics 650 (June 2021): A137. http://dx.doi.org/10.1051/0004-6361/202140644.

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Nuclear star clusters (NSCs) are the densest stellar systems in the Universe and are found in the centres of all types of galaxies. They are thought to form via mergers of star clusters such as ancient globular clusters (GCs) that spiral to the centre as a result of dynamical friction or through in situ star formation directly at the galaxy centre. There is evidence that both paths occur, but the relative contribution of either channel and their correlation with galaxy properties are not yet constrained observationally. Our aim was to derive the dominant NSC formation channel for a sample of 25 nucleated galaxies, mostly in the Fornax galaxy cluster, with stellar masses between Mgal ∼ 108 and 1010.5 M⊙ and NSC masses between MNSC ∼ 105 and 108.5 M⊙. Using Multi-Unit Spectroscopic Explorer data from the Fornax 3D survey and the ESO archive, we derived star formation histories, mean ages, and metallicities of NSCs, and compared them to the host galaxies. In many low-mass galaxies, the NSCs are significantly more metal poor than their hosts, with properties similar to GCs. In contrast, in the massive galaxies we find diverse star formation histories and cases of ongoing or recent in situ star formation. Massive NSCs (> 107 M⊙) occupy a different region in the mass–metallicity diagram than lower-mass NSCs and GCs, indicating a different enrichment history. We find a clear transition of the dominant NSC formation channel with both galaxy and NSC mass. We hypothesise that while GC accretion forms the NSCs of the dwarf galaxies, central star formation is responsible for the efficient mass build up in the most massive NSCs in our sample. At intermediate masses both channels can contribute. The transition between these formation channels seems to occur at galaxy masses Mgal ∼ 109 M⊙ and NSC masses MNSC ∼ 107 M⊙.
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Lee, Chang-Hwan. "Formation and Evolution of Neutron Star Binaries: Masses of Neutron Stars." EPJ Web of Conferences 20 (2012): 04002. http://dx.doi.org/10.1051/epjconf/20122004002.

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Dissertations / Theses on the topic "Star masses"

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Randriamampandry, Solohery Mampionona. "Stellar masses of star forming galaxies in clusters." University of the Western Cape, 2010. http://hdl.handle.net/11394/3028.

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Magister Scientiae - MSc
We determine the stellar mass of star forming galaxies in the X-ray luminous cluster MS 0451.6-0305 at z ∼ 0.54. The stellar masses are estimated from fitting model spectral energy distributions (SEDs) to deep, optical UBRIz observations obtained from WIYN 3.5m telescope and public NIR K-band image from Palomar Observatory telescope. The model SEDs are based on the stellar population synthesis (SPS) model of Bruzual & Charlot (2003) and Conroy et al. (2009) that span a wide range of age, star formation history, Initial Mass Function (IMF), metallicity and dust content. We measure stellar masses for galaxies down to M∗∼2×10⁸M(.) We find a tight correlation between stellar masses derived from the two SPSs. We compare the derived stellar masses to the dynamical masses for a set of 25 star forming galaxies. The dynamical masses are derived from high resolution, spectroscopic observations of emission lines from the DEIMOS spectrograph on the Keck telescope. A strong correlation is seen between the dynamical and stellar mass for the galaxies; and the star forming galaxies show fairly constant ratio between stellar and dynamical mass. When comparing to the field sample of Guzm ́an et al. (2003) of luminous compact blue galaxies, we see an excess of low mass galaxies in the cluster.
South Africa
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Queiroz, Anna Bárbara de Andrade. "Star horse : a Bayesian tool for determining masses, ages, distances and extinction for field stars." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/180515.

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Nos encontramos em uma localização vantajosa para o estudo da formação e evolução de galáxias espirais. Situados no disco da Via-Láctea, somos capazes de fazer observações detalhadas sobre as estrelas individuais que a compõem. Com o avanço tecnológico das últimas décadas, foi possível coletar um grande conjunto de informações, (e.g. composição química, cinemática, astrometria e parâmetros atmosféricos), com alta resolução para uma vasta parte do volume Galáctico. Com o objetivo de compreender melhor a nossa Galáxia, desenvolvemos uma ferramenta, chamada StarHorse, que estima parâmetros como distâncias, idades, massas e avermelhamento utilizando informação disponível em levantamentos espectroscópicos, fotométricos e astrométricos. O código StarHorse estima os parâmetros através de um método Bayesiano, que constrói uma distribuição de probabilidade a partir do cálculo de verossimilhança entre observações e modelos de evolução teórica e a partir de priores Galácticos bem conhecidos. Os parâmetros que o StarHorse estima são cruciais para estudos de arqueologia Galáctica. Com eles é possível investigar a estrutura, o histórico de formação estelar, a função de massa inicial, o mapa tridimensional da nossa Galáxia e também adicionar vínculos a modelos quemodinâmicos da Via Láctea Neste trabalho, focaremos na descrição e validação do método, testando sua aplicabilidade em levantamentos recentes de espectroscópica, astrometria e fotometria. Também disponibilizamos catálogos com distâncias e extinção para comunidade astronômica. As nossas distâncias e extinções se tornaram referência dentro da colaboração APOGEE e foram liberadas junto com o seu Data Release 14. Ademais, catálogos foram liberados para os surveys RAVE, Gaia-ESO e GALAH. Neste trabalho, exploramos os resultados do StarHorse, especialmente os resultados APOGEE, em um contexto amplo de arqueologia Galáctica.
We are in an advantageous position to study the formation and evolution of disk galaxies. By being inside the Milky Way, we are able to make detailed observations about the individual stars that compose it. With the technological revolution of the latest years, it has been possible to collect a massive set of information, (e.g. chemical composition, kinematics, astrometry, and atmospheric parameters), with high resolution for a large portion of the Galactic volume. With the goal to understand better our Galaxy, we developed a tool, called StarHorse, that can estimate distances, ages, masses, and extinction from the available spectroscopic, astrometric, and photometric information. StarHorse makes these estimates through a Bayesian method, that builds a probability distribution over the models by calculating a likelihood function between observation and stellar evolution models, and by using common knowledge about our Galaxy as priors. The parameters that StarHorse estimates are crucial to Galactic archaeology studies. With them, we can investigate the structure, the star formation history, the initial mass function, the three-dimensional dust map of our Galaxy, and provide constraints to chemodynamical models of the Milky Way. In this work, we focus on the description and validation of the method, testing its applicability in recent spectroscopic and astrometric surveys. We also make available catalogs with distances and extinctions to the astronomy community. Our distances and extinctions became a reference inside the APOGEE-team and were released as part of the SDSS Data Release 14. Moreover, we made available catalogs also to other spectroscopic surveys such as Gaia-ESO, RAVE, and GALAH. In this work, we also explore these results, especially for APOGEE, in a broad Galactic archaeology context.
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Imara, Nia, Abraham Loeb, Benjamin D. Johnson, Charlie Conroy, and Peter Behroozi. "A Model Connecting Galaxy Masses, Star Formation Rates, and Dust Temperatures across Cosmic Time." IOP PUBLISHING LTD, 2018. http://hdl.handle.net/10150/627101.

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We investigate the evolution of dust content in galaxies from redshifts z = 0 to z = 9.5. Using empirically motivated prescriptions, we model galactic-scale properties-including halo mass, stellar mass, star formation rate, gas mass, and metallicity-to make predictions for the galactic evolution of dust mass and dust temperature in main-sequence galaxies. Our simple analytic model, which predicts that galaxies in the early universe had greater quantities of dust than their low-redshift counterparts, does a good job of reproducing observed trends between galaxy dust and stellar mass out to z approximate to 6. We find that for fixed galaxy stellar mass, the dust temperature increases from z = 0 to z = 6. Our model forecasts a population of low-mass, high-redshift galaxies with interstellar dust as hot as, or hotter than, their more massive counterparts; but this prediction needs to be constrained by observations. Finally, we make predictions for observing 1.1 mm flux density arising from interstellar dust emission with the Atacama Large Millimeter Array.
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Güver, Tolga, Feryal Özel, Herman Marshall, Dimitrios Psaltis, Matteo Guainazzi, and Maria Díaz-Trigo. "SYSTEMATIC UNCERTAINTIES IN THE SPECTROSCOPIC MEASUREMENTS OF NEUTRON STAR MASSES AND RADII FROM THERMONUCLEAR X-RAY BURSTS. III. ABSOLUTE FLUX CALIBRATION." IOP PUBLISHING LTD, 2016. http://hdl.handle.net/10150/621974.

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Many techniques for measuring neutron star radii rely on absolute flux measurements in the X-rays. As a result, one of the fundamental uncertainties in these spectroscopic measurements arises from the absolute flux calibrations of the detectors being used. Using the stable X-ray burster, GS 1826-238, and its simultaneous observations by Chandra HETG/ACIS-S and RXTE/PCA as well as by XMM-Newton EPIC-pn and RXTE/PCA, we quantify the degree of uncertainty in the flux calibration by assessing the differences between the measured fluxes during bursts. We find that the RXTE/PCA and the Chandra gratings measurements agree with each other within their formal uncertainties, increasing our confidence in these flux measurements. In contrast, XMM-Newton EPIC-pn measures 14.0 +/- 0.3% less flux than the RXTE/PCA. This is consistent with the previously reported discrepancy with the flux measurements of EPIC-pn, compared with EPIC MOS1, MOS2, and ACIS-S detectors. We also show that any intrinsic time-dependent systematic uncertainty that may exist in the calibration of the satellites has already been implicity taken into account in the neutron star radius measurements.
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Benbakoura, Mansour. "Evolution des étoiles de faible masse en interaction : observations multi-techniques et modélisation des systèmes multiples." Thesis, Université de Paris (2019-....), 2019. http://www.theses.fr/2019UNIP7027.

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Cette thèse est consacrée à l'étude des étoiles de faible masse ayant dans leur environnement proche d'autres étoiles ou des planètes. Nous nous sommes concentrés sur l'influence des interactions avec ces compagnons sur l'évolution stellaire ainsi que leurs conséquences observables.Dans la première partie, nous présentons le modèle d'évolution des systèmes étoile–planète que nous avons développé au cours de cette thèse, nommé ESPEM (Évolution des Systèmes Planétaires Et Magnétisme). Ce modèle prend en compte de façon ab-initio des effets du vent stellaire magnétisé et de la dissipation de marée sur la rotation stellaire et l'orbite planétaire, simultanément avec l'évolution structurelle de l'étoile. Premièrement, nous l'utilisons pour étudier l'évolution séculaire de la rotation des étoiles hôtes de systèmes planétaires et montrons notamment que cette évolution peut être significativement différente de celle des étoiles isolées. Ensuite, nous examinons les prédictions de ce modèle concernant l'architecture orbitale des systèmes étoile–planète. Nos résultats suggèrent une interprétation aux distributions de périodes orbitales et de de rotation stellaire observées.Dans la deuxième partie, nous montrons en quoi l'observation d'étoiles binaires évoluées permet de tester les théories astrophysiques, notamment l'astérosismologie et l'interaction de marée. Dans un premier temps, nous présentons les résultats d'un programme d'observations que nous avons mené pendant plus de deux ans et qui nous a permis de caractériser 16 systèmes binaires à éclipses. Ensuite, nous comparons ces résultats avec ceux que nous avons obtenus en analysant cet échantillon à l'aide d'outils astérosismiques dans le but de vérifier l'exactitude de ces derniers. Enfin, en élargissant l'échantillon étudié à 30 autres étoiles binaires évoluées, nous testons la théorie de l'évolution de marée. Ceci nous permet à la fois de valider la théorie et de comprendre l'évolution des systèmes observés dans ce travail.Ce travail met en avant deux aspects de la spécificité des systèmes multiples. Premièrement, il montre en quoi l'évolution des étoiles est impactée par la présence d'un compagnon stellaire ou planétaire. Deuxièmement, il met en avant l'intérêt des étoiles binaires pour tester les théories astrophysiques et renforce la compréhension actuelle de l'évolution stellaire
This thesis is devoted to the study of low-mass stars having other stars or planets in their immediate environment. We focused on the influence of interactions with these companions on stellar evolution and their observable consequences.In the first part, we present the model of evolution of star–planet systems that we developed during this thesis, called ESPEM (French acronym for Evolution of Planetary Systems and Magnetism). This model incorporates ab-initio prescriptions to quantify the effects of magnetized stellar wind and tidal dissipation on stellar rotation and planetary orbit, simultaneously with the star's structural evolution. First, we use it to study the secular evolution of the rotation of planet-host stars and show that this evolution can be significantly different from that of isolated stars. Next, we examine the predictions of this model regarding the orbital architecture of star–planet systems. Our results suggest an interpretation to the observed distributions of orbital and stellar rotation periods.In the second part of the manuscript, we show how the observation of advanced binary stars allows us to test astrophysical theories, in particular asteroseismology and tidal interaction. First, we present the results of an observation program that we conducted for more than two years and that allowed us to characterize 16 eclipsing binary systems. Then, we compare these results with those obtained by analyzing this sample using asteroseismic tools to verify the accuracy of the latter. Finally, by extending the studied sample to 30 other advanced binary stars including an evolved primary, we test the theory of tidal evolution. This allows us both to validate the theory and to understand the evolution of the systems observed in this work.This work highlights two aspects of the specificity of multiple systems. First, it shows how the evolution of stars is affected by the presence of a stellar or planetary companion. Second, it emphasizes the interest of binary stars in testing astrophysical theories and reinforces the current understanding of stellar evolution
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Gallet, Florian. "Modélisation de l'évolution du moment cinétique des étoiles de faible masse." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENY055/document.

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En 1972, Skumanich découvre une relation empirique unique entre la période de rotation de surface des étoiles G et leur âge sur la séquence principale. Cette découverte ouvrit alors une nouvelle voie pour la datation stellaire : la gyrochronologie. Dès lors, bon nombre d'auteurs, entre la fin des années 80 et 90, se sont intéressés à l'évolution de la vitesse de rotation de surface des étoiles de faible masse ($M_*$ = 0.4 $M_{odot}$- 1.1 $M_{odot}$). Les premiers modèles phénoménologies sur le sujet été nés.L'évolution de la vitesse de rotation de ces étoiles commence à être raisonnablement bien reproduite par la classe de modèle paramétrique que je présente dans cette thèse. Par manque de descriptions théoriques satisfaisantes, seuls les effets globaux des mécanismes physiques impliqués sont ici décris. Le principal enjeu est d'étudier le cadre et la façon dont le moment cinétique stellaire est impacté par ces processus tout en contraignant leurs principales caractéristiques.Au cours de ma thèse, j'ai modélisé les trajets rotationnels des enveloppes externes et médianes des distributions de période de rotation de 18 amas stellaire entre 1 Myr et 1 Gyr. Ceci m'a permis d'analyser la dépendance temporelle des mécanismes physiques impliqués dans l'évolution du moment cinétique des étoiles de type solaire. Les résultats que j'ai obtenus montrent que l'évolution de la rotation différentielle interne impact fortement la convergence rotationnelle (relation empirique de Skumanich), l'évolution de l'abondance de surface en lithium, et les intensités du champ magnétique généré par effet dynamo. En plus de reproduire ces enveloppes externes, le modèle que j'ai développé fournit des contraintes sur les mécanismes de redistribution interne du moment cinétique et sur les durées de vie des disques circumstellaires, supposés responsables de la régulation rotationnelle observée durant les quelques premiers millions d'années de la pré-séquence principale. L'extension du modèle aux étoiles moins massives (0.5 et 0.8 $M_{odot}$) que j'ai réalisé, a également fournis la dépendance en masse de ces différents processus physiques.Cette étape à notamment ajoutée de fortes contraintes sur les temps caractéristiques associés au transport de moment cinétique entre le coeur et l'enveloppe, sur l'efficacité du freinage magnétique vraisemblablement reliée à un changement de topologie des étoiles de type solaire vers celles de 0.5 $M_{odot}$, et sur l'histoire rotationnelle, interne comme de surface, des étoiles entre 1 Myr à 1 Gyr
In 1972, Skumanich discovers a unique empirical relationship between the rotation period of the surface of G star and their age on the main sequence. This discovery then opened a new path for stellar dating: the gyrochronology. Therefore, many authors in the late 80's and the begenning 90's, were interested in the evolution of the surface angular velocity of low-mass stars ($M_*$ = 0.4 $M_{odot}$- 1.1 $M_{odot}$). The first phenomenological models on the subject were born.The angular velocity evolution of these stars begins to be reasonably well reproduced by the class of parametrical model that I present in this thesis. Because of the lack of adequate theoretical descriptions, only the overall effects of the physical mechanisms involved are described here. The main issue is to study the framework and how the stellar angular momentum is affected by these processes and to constrain their main characteristics.Over the course of my thesis, I modelled the rotational tracks of external and median envelopes and median of rotation period distributions of 18 stellar clusters between 1 Myr and 1 Gyr. This allowed me to analyse the time dependence of the physical mechanisms involved in the angular momentum evolution of solar-type stars. The results I obtained show that the evolution of the internal differential rotation significantly impact the rotational convergence (empirical Skumanich's relationship), the evolution of the surface lithium abundance, and the intensity of the magnetic field generated by dynamo effect. In addition to the reproduction of these external envelopes, the model I developed provides constraints on the mechanisms of internal redistribution of angular momentum and the lifetimes of circumstellar disks, that are held responsible for the rotational regulation observed during the first few million years of pre-main sequence. The extension of the model to less massive stars (0.5 et 0.8 $M_{odot}$) that I performed also provided the mass dependence of these physical processes. Most specifically, this step added strong constraints on the characteristic time associated to the transport of angular momentum between the core and the envelope, on the efficiency of magnetic braking likely related to a change of topology from solar-type stars to those of 0.5 $M_{odot}$, and on the internal and external rotational history of stars from 1 Myr to 1 Gyr
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Al, Muntafki Khudhair Abbas assaf. "Silicon monoxide masers and the magnetic field of R Cassiopeiae." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/silicon-monoxide-masers-and-the-magnetic-field-of-r-cassiopeiae(73264bdb-d77e-4182-8840-f6e94f6bebe8).html.

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Silicon monoxide maser emission has been detected in many evolved stars in circumstellar envelopes in different vibrationally-excited rotational transitions. It is considered a good tracer to study the dynamics in a region close to the photosphere of the star. We present multi-epoch, total intensity, high-resolution images of 43 GHz, v=1, J=1-0 SiO maser emission toward the Mira variable R Cas. In total we have 23 epochs of data for R Cas at approximate monthly intervals over an optical pulsation phase range of φ = 0.158 to φ = 1.782. These maps show a ring-like distribution of the maser features in a shell, which is assumed to be centred on the star at average radius of 1.6 → 2.3 times the radius of star, R⋆. It is clear from these images that the maser emission is significantly extended around the star. At some epochs a faint outer arc can be seen at about 4 R⋆. The intensity of the emission waxes and wanes during the stellar phase. Some maser features are seen infalling as well as outflowing. We have made initial comparisons of our data with models by Gray et al. (2009). We have investigated the polarization morphology by mapping the linear and circular polarization of SiO masers in the v=1, J=1-0 transition. We found that some of the polarization vectors are either tangential or radial, which indicate a bimodal structure of the linear polarization morphology. Other angles can be seen as well. This is consistent with a radial, stellar-centred magnetic field in the SiO maser shell. We found in some isolated features the fractional linear polarization exceeds 100%. In other features, the polarization angle abruptly flips by 90◦. We found that our data are in the regime that the Zeeman splitting rate g is much greater than the stimulated emission rate R which in turn is greater than the decay rate , which indicates that the solution of Goldreich et al. (1973) can be applied.
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Thoroughgood, Timothy David. "The masses of cataclysmic variable stars." Thesis, University of Sheffield, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.419603.

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Booth, H. J. "Guide star lasers." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300872.

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Avison, Adam Matthew. "Methanol masers and the environments of massive star formation." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/methanol-masers-and-the-environments-of-massive-star-formation(6387a264-f396-41a1-9c28-8dbd1a20be7f).html.

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This thesis presents an investigation into the environments of massive young stellar objects during the period of their evolution where 6.7GHz methanol masers form. Radio observations (both spectral line and continuum data) from the Methanol MultiBeam Survey (MMB) and multiple wavelength infrared data are used to characterise the physical conditions of environments associated with methanol masers. The velocity structures of methanol masers with velocity spreads spanning over 10km/s from the MMB-ATCA dataset are investigated. These sources are seen to have more structure than those with small velocity distributions, providing more information on the physical characteristics of the maser environments. A number of possible morphologies including potential disk, ring and outflow types are suggested for these source from both their velocity structure and position velocity distributions. The MMB-8GHz continuum dataset is used to define the size (e.g Hyper Compact, Ultra Compact or Compact) for Hii regions observed within the MMB-ATCA data. These Hii regions are found to be predominantly in the UCHii or HCHii size regime. Statistical testing to assess any difference in Hii region sizes between sources with maser/continuum source separation of > 0.2 parsecs and those of separation >0.2 parsecs, finds (at between the 80% and 93% significance level) that Hii sources with closely associated maser and continuum emission are smaller in size, suggesting that these sources are less evolved. MIPS 24 and 70µm data are used to define the colour magnitude space inhabited by MMB masers and Hii regions which are found to occupy a large region of log(F70 /F24 ) colour space between a lower limit value of 0.4 and up to 5. Kolmogorov-Smirnov testing of these data show statistically significant differences in the infrared (IR) environments between isolated masers and masers with associated Hii regions, indicating that isolated masers trace younger less evolved protostellar objects. Tests are conducted of 10 degree regions in galactic longitude of the Galactic Plane finding regions with statistically different IR environments indicating the relative ages of the star forming regions in the Galaxy. A null results was found for differing IR environments of masers based on the masers luminosity. An initial study of the IR environments of methanol masers using early data from the Hi-GAL survey, using the PACS and SPIRE instruments onboard the Herschel space telescope. With this investigation the colour-colour space characteristics and spectral energy distributions of the seven MMB masers in the PACS dataset are found and compared to non-maser Herschel sources, providing the basis for further investigation as more Herschel data becomes available.
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Books on the topic "Star masses"

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K, Dupree Andrea, Lago, M. T. V. T., and North Atlantic Treaty Organization. Scientific Affairs Division., eds. Formation and evolution of low mass stars. Dordrecht: Kluwer Academic Publishers, 1988.

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ESO/CTIO, Workshop on Mass Loss on the AGB and Beyond (2nd 1992 La Serena Chile). Second ESO/CTIO Workshop on Mass Loss on the AGB and Beyond: La Serena, Chile, 21-24 January 1992 : proceedings. Garching bei München: ESO, 1993.

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Prusti, Timo Juhani. Infrared studies of low mass formation. [Groningen, Netherlands]: Rijksuniversiteit Groningen, 1992.

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Anthony, James. Star wars, Masters of Teräs Käsi: Prima's official hints and tips. Rocklin, Calif: Prima Pub., 1998.

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Carol, Skakel, ed. Ancient wisdom: Invoking the power of your soul star. Lynnwood, Wa: Aurum Pub. Co., 1995.

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Star Wars: The legendary Yoda. London: Dorling Kindersley Limited, 2013.

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Vornholt, John. Masks: Star Trek: The Next Generation #7. New York: Pocket Books, 1989.

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Saunders, Catherine. Star Wars: The Jedi and the Force. New York: DK Publishing, 2015.

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Greve, Delia, ed. Star Wars Lightsabers: (2010) A Guide to Weapons of the Force. New York, USA: Scholastic, Inc., 2010.

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R, Stalio, Willson L. A, and Trieste Workshop on Stellar Pulsation and Mass Loss (1987), eds. Pulsation and mass loss in stars: Proceedings of a workshop, held in Trieste, Italy, September 14-18, 1987. Dordrecht: Kluwer Academic Publishers, 1988.

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Book chapters on the topic "Star masses"

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Herczeg, Tibor J. "Neutron Star Masses." In Active Close Binaries, 693–727. Dordrecht: Springer Netherlands, 1990. http://dx.doi.org/10.1007/978-94-009-0679-2_50.

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Popov, Sergei, David Blaschke, Hovik Grigorian, and Mikhail Prokhorov. "Neutron star masses: dwarfs, giants and neighbors." In Isolated Neutron Stars: From the Surface to the Interior, 381–85. Dordrecht: Springer Netherlands, 2007. http://dx.doi.org/10.1007/978-1-4020-5998-8_47.

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Nakano, Takenori. "The Formation of Planets Around Stars of Various Masses and the Origin and the Evolution of Circumstellar Dust Clouds." In Star Forming Regions, 301–13. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-4782-5_90.

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Thronson, Harley A. "No More Heterodyne Blues: Gas Masses From Millimeter and Sub-Millimeter Continuum Photometry." In Galactic and Extragalactic Star Formation, 621–26. Dordrecht: Springer Netherlands, 1988. http://dx.doi.org/10.1007/978-94-009-2973-9_40.

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Erb, Dawn K., Charles C. Steidel, Alice E. Shapley, Max Pettini, Naveen A. Reddy, and Kurt L. Adelberger. "Star-Forming Galaxies at Z ∼ 2: Stellar and Dynamical Masses." In Starbursts, 303–6. Dordrecht: Springer Netherlands, 2005. http://dx.doi.org/10.1007/1-4020-3539-x_54.

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James, Phil. "Nearby Galaxies with UKIRT: Uncovering Star Formation, Structure and Stellar Masses." In Thirty Years of Astronomical Discovery with UKIRT, 213–27. Dordrecht: Springer Netherlands, 2013. http://dx.doi.org/10.1007/978-94-007-7432-2_20.

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Walton, N. A., M. J. Barlow, D. J. Monk, and R. E. S. Clegg. "Abundances and Nebular and Central Star Masses for Magellanic Cloud Planetary Nebulae." In The Magellanic Clouds, 334–36. Dordrecht: Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-3432-3_79.

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Kylafis, Nikolaos D. "Masers and Star Formation." In The Physics of Star Formation and Early Stellar Evolution, 269–86. Dordrecht: Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-3642-6_7.

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Karttunen, Hannu, Pekka Kröger, Heikki Oja, Markku Poutanen, and Karl Johan Donner. "Binary Stars and Stellar Masses." In Fundamental Astronomy, 213–19. Berlin, Heidelberg: Springer Berlin Heidelberg, 2003. http://dx.doi.org/10.1007/978-3-662-05333-1_9.

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Horvath, Jorge E., and Rodolfo Valentim. "The Masses of Neutron Stars." In Handbook of Supernovae, 1–14. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-20794-0_67-1.

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Conference papers on the topic "Star masses"

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Lattimer, James M. "Neutron star masses and radii." In XIAMEN-CUSTIPEN WORKSHOP ON THE EQUATION OF STATE OF DENSE NEUTRON-RICH MATTER IN THE ERA OF GRAVITATIONAL WAVE ASTRONOMY. AIP Publishing, 2019. http://dx.doi.org/10.1063/1.5117791.

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YAKOVLEV, D. G. "MEASUREMENTS OF NEUTRON STAR MASSES." In Proceedings of the International Symposium EXOCT07. WORLD SCIENTIFIC, 2008. http://dx.doi.org/10.1142/9789812797049_0029.

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Mengel, Sabine, Matthew D. Lehnert, Niranjan A. Thatte, and Reinhard Genzel. "Dynamical masses of young star clusters in interacting galaxies." In Astronomical Telescopes and Instrumentation, edited by Puragra Guhathakurta. SPIE, 2003. http://dx.doi.org/10.1117/12.456511.

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Denney, Kelly. "Measuring black hole masses at high redshift." In Nuclei of Seyfert galaxies and QSOs - Central engine & conditions of star formation. Trieste, Italy: Sissa Medialab, 2013. http://dx.doi.org/10.22323/1.169.0050.

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Peterson, Bradley, and Catherine Grier. "Masses of Black Holes in Active Galactic Nuclei." In Nuclei of Seyfert galaxies and QSOs - Central engine & conditions of star formation. Trieste, Italy: Sissa Medialab, 2013. http://dx.doi.org/10.22323/1.169.0030.

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Lamb, Frederick K., M. Coleman Miller, and Dimitrios Psaltis. "Constraints on neutron star masses and radii from kilohertz QPOs." In Accretion processes in astrophysical systems: Some like it hot! - eigth astrophysics conference. AIP, 1998. http://dx.doi.org/10.1063/1.55923.

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Steiner, Andrew, Tobias Fischer, Stefano Gandolfi, and M. Hempel. "Constraining the Dense Matter from Neutron Star Masses and Radii." In XII International Symposium on Nuclei in the Cosmos. Trieste, Italy: Sissa Medialab, 2013. http://dx.doi.org/10.22323/1.146.0038.

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Seleznev, A. F., and A. A. Malofeeva. "A search of unresolved binaries in open clusters by the photometry data in visible and infrared." In ASTRONOMY AT THE EPOCH OF MULTIMESSENGER STUDIES. Proceedings of the VAK-2021 conference, Aug 23–28, 2021. Crossref, 2022. http://dx.doi.org/10.51194/vak2021.2022.1.1.194.

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The general idea is to find the photometric diagram where the unresolved binary stars are well detached from the singlestars, even for small values of the component mass ratio q. We use the diagram (H-W2)-W1—W2-(BP-K) to estimate thebinary and multiple star ratio and the distribution of q for the Pleiades in the primary component mass interval between0.5 and 1.8 solar masses. A large number of binaries with secondary components being brown dwarfs or stars with theremnants of protostellar discs providing slight infrared excess are among the low-mass stars with the mass of the primarycomponent lower than 0.5 solar masses.
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Antokhina, E., I. Antokhin, G. Lenoir-Craig, N. St-Louis, and A. Moffat. "Light-curve modelling in a Roche plus stellar wind model: the massive binary WR22." In ASTRONOMY AT THE EPOCH OF MULTIMESSENGER STUDIES. Proceedings of the VAK-2021 conference, Aug 23–28, 2021. Crossref, 2022. http://dx.doi.org/10.51194/vak2021.2022.1.1.034.

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A code for the synthesis of light curves of close binaries in the Roche model is proposed which incorporates a stellarwind around one of the stars. The code makes it possible to analyze observations of binary systems containing Wolf-Rayetstars. This paper presents the results of the application of this code to the spectroscopic binary WR22, whose componentsare stars of spectral types WN7h and O9III-V (P = 80.336 d , e ∼ 0.6). The light curves were obtained with one of theBRITE-Constellation space-based telescopes. Two solutions to the problem were found, corresponding to two possibleluminosity classes of the O star, O9III and O9V. For each solution, the orbital inclination, the masses of the components,the temperature of the WR star, the WR mass-loss rate, and other parameters were determined. The resulting stellarparameters favour the solution for the WN7h+O9V model
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Popova, E. A., D. A. Ladeyschikov, M. S. Kirsanova, and A. M. Sobolev. "Physical parameters of molecular clumps in the S254—S258 star formation region." In Всероссийская с международным участием научная конференция студентов и молодых ученых, посвященная памяти Полины Евгеньевны Захаровой «Астрономия и исследование космического пространства». Ural University Press, 2021. http://dx.doi.org/10.15826/b978-5-7996-3229-8.39.

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This research is focusing on studying of physical parameters in the S254—S258 star-formation complex. The following parameters were derived: column densities, clump masses, and highdensity tracers optical depth, including CS and HCO+ molecules. Different gas and dust tracers maps were used, including CO molecular lines, Bolocam 1.1 mm continuum emission and near-infrared extinction map. We also used the available CS and HCO+ data, which cover part of the S254-S258 region to make conclusions regarding the distribution of highdensity gas. The resulted values of physical parameters obtained through different tracers are slightly different. The discussion about the possible reason for the difference is provided.
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Reports on the topic "Star masses"

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Hochron, D. R., B. W. Lynn, and S. B. Selipsky. An upper bound on Q-star masses. Office of Scientific and Technical Information (OSTI), June 1992. http://dx.doi.org/10.2172/94554.

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Malchenko, Svitlana L., Davyd V. Mykoliuk, and Arnold E. Kiv. Using interactive technologies to study the evolution of stars in astronomy classes. [б. в.], February 2020. http://dx.doi.org/10.31812/123456789/3752.

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In astrophysics, a significant role is played by observations. During astronomy classes in the absence of surveillance tools interactive programmes such as an interactive programme for space objects simulation can be used as Universe Sandbox2. The aim of this work is to implement interactive programmes for effective astronomy teaching, understanding material and increasing cognitive interest. We observe the evolution of stars while using Universe Sandbox2 during the study of the topic “Evolution of stars”. Using this programme students have an opportunity to get acquainted with the existence of stars with different masses, their differences, to observe changes in the physical characteristics of stars such as: mass, temperature, speed velocity, luminosity, radius and gravity. It will help to develop the ability to analyze, to compare, to form scientific worldview, to develop the attraction for research, to raise the interest for studying astronomy.
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Hogan, Geoff, and C. E. Webb. A CW Laser Master Oscillator for a Scaleable Sodium Guide Star. General Issues. Fort Belvoir, VA: Defense Technical Information Center, January 1997. http://dx.doi.org/10.21236/ada326345.

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Li, J., C. Lam, W. A. Dawson, B. S. Gaudi, N. R. Golovich, M. Medford, F. Abdurrahman, and R. L. Beaton. From Stars to Compact Objects: The Initial-Final Mass Relation. Office of Scientific and Technical Information (OSTI), October 2019. http://dx.doi.org/10.2172/1572254.

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Alsanius, Beatrix, and Emina Mulaosmanovic. Cool fruits - Effekter av lagringstid samt lagringstemperatur på förekomst av Listeria monocytogenes i färsk fruktcocktail. Fakulteten för landskapsarkitektur, trädgårds- och växtproduktionsvetenskap, Sveriges lantbruksuniversitet, 2022. http://dx.doi.org/10.54612/a.36vkme5hjo.

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Färska fruktsallader (fruktcocktail) efterfrågas av konsumenter. Med dagens ansträngda elpriser ställs frågan om kyltemperaturen under framställning, transport och display i butiken skulle kunna höjas från 4 till 8 °C utan att äventyra livsmedelssäkerheten för dessa produkter. Föreliggande rapport bygger på en litteraturstudie och en provokationsstudie, där den köldtoleranta (psykrofila) organismen Listeria monocytogenes användes som modellorganism. Litteraturstudien genomfördes som en systematisk litteratursökning i databasen Web‐of‐Science. I den experimentella delen studerades tillväxtbeteendet av L. monocytogenes med hänsyn till lagringstemperatur och lagringstid i en färsk fruktcocktail bestående av ananas, röda äpplen, nätmelon och röda druvor. Den experimentella delen byggde på frågeställningen om lagringstemperaturen kan höjas från 4 °C till 8 °C samt från en rekommenderad lagringslängd på 4 dagar till 8 dagar, med hänsyn till förekomst av L. monocytogenes. En klinisk stam av L. monocytogenes inokulerades i färdiga råa fruktsallader. Tre temperaturregimer tillämpades: 4 °C i åtta dagar, 8 °C i åtta dagar samt 4 °C i ett dygn följt av 8 °C under återstående lagringstid på totalt åtta dagar (så kallad dynamisk temperaturregim). Vi fann att modellorganismen hade förökat sig efter åtta dagars lagringstid i samtliga behandlingar, dock avsevärt långsammare vid lagring i 4 °C, jämfört med kontinuerlig lagring i 8 °C samt den dynamiska behandlingen. Vid 4 °C lagringstemperatur visade L. monocytogenes en tillväxtpotential av knappt ett halvt log‐värde, samt med log 1,37 respektive log 1,23 vid 8 °C lagringstemperatur respektive dynamisk lagring, trots att fruktsalladens pH låg under minimi‐kraven för L. monocytogenes. I synnerhet i behandlingarna med högre temperatur förekom en massiv uppförökning av jästsvampar. Utifrån föreliggande resultat av litteraturundersökningen förordar vi ingen förhöjning av lagringstemperatur eller förlängning av lagringstid.
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Lazonick, William, Philip Moss, and Joshua Weitz. Equality Denied: Tech and African Americans. Institute for New Economic Thinking, February 2022. http://dx.doi.org/10.36687/inetwp177.

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Thus far in reporting the findings of our project “Fifty Years After: Black Employment in the United States Under the Equal Employment Opportunity Commission,” our analysis of what has happened to African American employment over the past half century has documented the importance of manufacturing employment to the upward socioeconomic mobility of Blacks in the 1960s and 1970s and the devastating impact of rationalization—the permanent elimination of blue-collar employment—on their socioeconomic mobility in the 1980s and beyond. The upward mobility of Blacks in the earlier decades was based on the Old Economy business model (OEBM) with its characteristic “career-with-one-company” (CWOC) employment relations. At its launching in 1965, the policy approach of the Equal Employment Opportunity Commission assumed the existence of CWOC, providing corporate employees, Blacks included, with a potential path for upward socioeconomic mobility over the course of their working lives by gaining access to productive opportunities and higher pay through stable employment within companies. It was through these internal employment structures that Blacks could potentially overcome barriers to the long legacy of job and pay discrimination. In the 1960s and 1970s, the generally growing availability of unionized semiskilled jobs gave working people, including Blacks, the large measure of employment stability as well as rising wages and benefits characteristic of the lower levels of the middle class. The next stage in this process of upward socioeconomic mobility should have been—and in a nation as prosperous as the United States could have been—the entry of the offspring of the new Black blue-collar middle class into white-collar occupations requiring higher educations. Despite progress in the attainment of college degrees, however, Blacks have had very limited access to the best employment opportunities as professional, technical, and administrative personnel at U.S. technology companies. Since the 1980s, the barriers to African American upward socioeconomic mobility have occurred within the context of the marketization (the end of CWOC) and globalization (accessibility to transnational labor supplies) of high-tech employment relations in the United States. These new employment relations, which stress interfirm labor mobility instead of intrafirm employment structures in the building of careers, are characteristic of the rise of the New Economy business model (NEBM), as scrutinized in William Lazonick’s 2009 book, Sustainable Prosperity in the New Economy? Business Organization and High-Tech Employment in the United States (Upjohn Institute). In this paper, we analyze the exclusion of Blacks from STEM (science, technology, engineering, math) occupations, using EEO-1 employment data made public, voluntarily and exceptionally, for various years between 2014 and 2020 by major tech companies, including Alphabet (Google), Amazon, Apple, Cisco, Facebook (now Meta), Hewlett Packard Enterprise, HP Inc., Intel, Microsoft, PayPal, Salesforce, and Uber. These data document the vast over-representation of Asian Americans and vast under-representation of African Americans at these tech companies in recent years. The data also shine a light on the racial, ethnic, and gender composition of large masses of lower-paid labor in the United States at leading U.S. tech companies, including tens of thousands of sales workers at Apple and hundreds of thousands of laborers & helpers at Amazon. In the cases of Hewlett-Packard, IBM, and Intel, we have access to EEO-1 data from earlier decades that permit in-depth accounts of the employment transitions that characterized the demise of OEBM and the rise of NEBM. Given our findings from the EEO-1 data analysis, our paper then seeks to explain the enormous presence of Asian Americans and the glaring absence of African Americans in well-paid employment under NEBM. A cogent answer to this question requires an understanding of the institutional conditions that have determined the availability of qualified Asians and Blacks to fill these employment opportunities as well as the access of qualified people by race, ethnicity, and gender to the employment opportunities that are available. Our analysis of the racial/ethnic determinants of STEM employment focuses on a) stark differences among racial and ethnic groups in educational attainment and performance relevant to accessing STEM occupations, b) the decline in the implementation of affirmative-action legislation from the early 1980s, c) changes in U.S. immigration policy that favored the entry of well-educated Asians, especially with the passage of the Immigration Act of 1990, and d) consequent social barriers that qualified Blacks have faced relative to Asians and whites in accessing tech employment as a result of a combination of statistical discrimination against African Americans and their exclusion from effective social networks.
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Yaron, Zvi, Abigail Elizur, Martin Schreibman, and Yonathan Zohar. Advancing Puberty in the Black Carp (Mylopharyngodon piceus) and the Striped Bass (Morone saxatilis). United States Department of Agriculture, January 2000. http://dx.doi.org/10.32747/2000.7695841.bard.

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Both the genes and cDNA sequences encoding the b-subunits of black carp LH and FSH were isolated, cloned and sequenced. Sequence analysis of the bcFSHb and LHb5'flanking regions revealed that the promoter region of both genes contains canonical TATA sequences, 30 bp and 17 bp upstream of the transcription start site of FSHb and LHb genes, respectively. In addition, they include several sequences of cis-acting motifs, required for inducible and tissue-specific transcriptional regulation: the gonadotropin-specific element (GSE), GnRH responsive element (GRE), half sites of estrogen and androgen response elements, cAMP response element, and AP1. Several methods have been employed by the Israeli team to purify the recombinant b subunits (EtOH precipitation, gel filtration and lentil lectin). While the final objective to produce pure recombinantGtH subunits has not yet been achieved, we have covered much ground towards this goal. The black carp ovary showed a gradual increase in both mass and oocyte diameter. First postvitellogenic oocytes were found in 5 yr old fish. At this age, the testes already contained spermatozoa. The circulating LH levels increased from 0.5 ng/ml in 4 yr old fish to >5ng/ml in 5 yr old fish. In vivo challenge experiments in black carp showed the initial LH response of the pituitary to GnRH in 4 yr old fish. The response was further augmented in 5 yr old fish. The increase in estradiol level in response to gonadotropic stimulation was first noted in 4 yr old fish but this response was much stronger in the following year. In vivo experiments on the FSHb and LHb mRNA levels in response to GnRH were carried out on common carp as a model for synchronom spawning cyprinids. These experiments showed the prevalence of FSHP in maturing fish while LHP mRNA was prevalent in mature fish, especially in females. The gonadal fat-pad was found to originate from the retroperitoneal mesoderm and not from the genital ridge, thus differing from that reported in certain amphibians This tissue possibly serves as the major source of sex steroids in the immature black carp. However, such a function is taken over by the developing gonads in 4 yr old fish. In the striped bass, we described the ontogeny of the neuro-endocrine parameters along the brain-pituitary-gonadal axis during the first four years of life, throughout gonadal development and the onset of puberty. We also described the responsiveness of the reproductive axis to long-term hormonal manipulations at various stages of gonadal development. Most males reached complete sexual maturity during the first year of life. Puberty was initiated during the third year of life in most females, but this first reproductive cycle did not lead to the acquisition of full sexual maturity. This finding indicates that more than one reproductive cycle may be required before adulthood is reached. Out of the three native GnRHs present in striped bass, only sbGnRH and cGnRH II increased concomitantly with the progress of gonadal development and the onset of puberty. This finding, together with data on GtH synthesis and release, suggests that while sbGnRH and cGnRH II may be involved in the regulation of puberty in striped bass, these neuropeptides are not limiting factors to the onset of puberty. Plasma LH levels remained low in all fish, suggesting that LH plays only a minor role in early gonadal development. This hypothesis was further supported by the finding that experimentally elevated plasma LH levels did not result in the induction of complete ovarian and testicular development. The acquisition of complete puberty in 4 yr old females was associated with a rise in the mRNA levels of all GtH subunit genes, including a 218-fold increase in the mRNA levels of bFSH. mRNA levels of the a and PLH subunits increased only 11- and 8-fold, respectively. Although data on plasma FSH levels are unavailable, the dramatic increase in bFSH mRNA suggests a pivotal role for this hormone in regulating the onset and completion of puberty in striped bass. The hormonal regulation of the onset of puberty and of GtH synthesis and release was studied by chronic administration of testosterone (T) and/or an analog of gonadotropin-releasing hormone (G). Sustained administration of T+G increased the mRNA levels of the PLH subunit to the values characteristic of sexually mature fish, and also increased the plasma levels of LH. However, these changes did not result in the acceleration of sexual maturation. The mRNA levels of the bFSH subunit were slightly stimulated, but remained about 1/10 of the values characteristic of sexually mature fish. It is concluded that the stimulation of FSH gene expression and release does not lead to the acceleration of sexual maturity, and that the failure to sufficiently stimulate the bFSH subunit gene expression may underlie the inability of the treatments to advance sexual maturity. Consequently, FSH is suggested to be the key hormone to the initiation and completion of puberty in striped bass. Future efforts to induce precocious puberty in striped bass should focus on understanding the regulation of FSH synthesis and release and on developing technologies to induce these processes. Definite formulation of hormonal manipulation to advance puberty in the striped bass and the black carp seems to be premature at this stage. However, the project has already yielded a great number of experimental tools of DNA technology, slow-release systems and endocrine information on the process of puberty. These systems and certain protocols have been already utilized successfully to advance maturation in other fish (e.g. grey mullet) and will form a base for further study on fish puberty.
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