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Journal articles on the topic 'Astronomy, Astrophysics, Physical sciences'

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1

Rey-Watson, Joyce. "Online Bibliographic Resources in Astronomy and Astrophysics." International Astronomical Union Colloquium 110 (1989): 84–86. http://dx.doi.org/10.1017/s0252921100003006.

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Online searches may be performed in astronomy and astrophysics either by OBJECT or by SUBJECT. Until recently, although object searches could be performed on a variety of databases in the physical sciences, results were poor and incomplete. Only if an object were mentioned by name in the title or abstract could one hope for any hits at all. The greatest blessing to befall the astronomical community was the advent of SIMBAD (Sets of Identifications, Measurements and Bibliography for Astronomical Data), a database in which searches are conducted by OBJECT only. It is produced and accessible from the Centre de Donnees de Strasbourg (CDS), Observatoire Astronomique, and is the result of many years of arduous work by a few dedicated astronomers and computer scientists. It is comprised of the merging of two earlier databases, the Catalog of Stellar Identifications (CSI) and the Bibliographical Star Index (BSI)
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2

Fedotova, Maria, Dmitry Klimachkov, and Arakel Petrosyan. "Variable Density Flows in Rotating Astrophysical Plasma. Linear Waves and Resonant Phenomena." Universe 7, no. 4 (2021): 87. http://dx.doi.org/10.3390/universe7040087.

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New observational data and modeling of physical processes constantly appear in the young and rapidly developing branch of science of plasma astrophysics. However, there is a lack of theoretical studies in the field of plasma astrophysics, that could unite the physics of various objects in the Universe, explain the observed phenomena and contribute to the improvement of numerical modeling schemes efficiency. This article makes up for this shortcoming by introducing different models, taking into account the various properties of plasma objects. We present a review of the latest magnetohydrodynamic theories of wave processes in rotating astrophysical plasma, taking into account important and common properties of astrophysical objects as compressibility and stratification.
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3

PETROVA, M. A., and N. A. SHAKHT. "Alexander Nikolaevich Deutsch on the occasion of his 120th anniversary." Astronomical and Astrophysical Transactions, Vol. 32, No. 1, Volume 32, Numéro 1 (September 1, 2020): 45–58. http://dx.doi.org/10.17184/eac.4633.

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The year 2019 is the year of the 120th anniversary of Alexander Nikolaevich Deutsch (1899-1986), the Pulkovo astronomer, doctor of physical and mathematical Sciences, Professor, who for many years was the head of the Department of photographic astrometry and stellar astronomy of the Main Astronomical Observatory, Russian Academy of Sciences (GAO RAS), the supervisor and teacher of several generations of Pulkovo astronomers and employees of other observatories. This article presents the scientific and social activities of A.N. Deutsch. Archived data is provided that evidence his participation, along with other Pulkovo employees, in the salvation of the property and scientific Fund of the Pulkovo Observatory during the great Patriotic war, as well as in the work to restore the Observatory. The article is based on the presentation given to and approved by the conference "Astrometry: yesterday, today, tomorrow" (Sternberg Astronomical Institute, Moscow State University, October 14-16, 2019).
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Lück, Wolfgang. "The PHYS Database: A New Cooperation with AAA." International Astronomical Union Colloquium 110 (1989): 87–88. http://dx.doi.org/10.1017/s0252921100003018.

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Since 1979 the Fachinformationszentrum Karlsruhe produces the bibliographic database PHYS which covers the worldwide literature in physics. The database is available on STN International. The database contains about 1,2 million citations in all fields of physics ranging from mathematical physics, elementary particles and field theories, nuclear, atomic and molecular physics, optics, acoustics and fluid dynamics, plasma physics, condensed matter physics, materials science, physical chemistry and biophysics up to geophysics, astronomy and astrophysics. The annual update contains more than 120.000 citations. The database is updated bimonthly. All kinds of literature are included from journal articles, conference papers, books and reports up to dissertations. The citations in the database are in English, publications in other languages have translated English title and abstract. Astronomy and astrophysics are covered in PHYS completely as possible. In 1987 there were more than 21.000 citations in these fields. There are many citations which are classified in PHYS into other fields like atomic or plasma physics and optics and which are not numbered to astronomy but may have a specific relevance for astronomers.
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Daniel Omodeo, Pietro. "The Scientific Culture of the Baltic Mathematician, Physician, and Calendar-Maker Laurentius Eichstadt (1596–1660)." Journal for the History of Astronomy 48, no. 2 (2017): 135–59. http://dx.doi.org/10.1177/0021828617703847.

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This paper is devoted to Laurentius Eichstadt, a Baltic astronomer of the generation between Tycho and Hevelius. As a calendar-maker, Eichstadt used and tested the astronomical tables and the planetary theories of his elder contemporaries, Longomontanus and Kepler; as a town physician and gymnasium professor, he taught mathematics and astronomy alongside medicine and natural philosophy in Stettin and Gdańsk. Eichstadt’s indefatigable engagement with theory, practice, and teaching is marked by his continuous reassessment, adjustment, and revision of views in astronomy, physics, and metaphysics, aimed at bringing these fields in better agreement with each other and with empirical observation. Eichstadt’s critical attitude did not prevent him from remaining committed to his scholastic legacy. As a matter of fact, his creative reworking and teaching of astronomy and philosophy bear witness to the long vitality of the northern European scientific tradition rooted in Melanchthonian literacy and Aristotelian philosophy. The work and conceptions of this participant in the astronomical debates of the early seventeenth century offers us an insight into the complex interplay of technical astronomy and metaphysical discourse in a time of transition from a geometrical approach to planetary theory resting on Aristotelian metaphysics to a post-Keplerian physical–mathematical science unifying heavens and earth.
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6

Kragh, Helge. "The Nobel Prize System and the Astronomical Sciences." Journal for the History of Astronomy 48, no. 3 (2017): 257–80. http://dx.doi.org/10.1177/0021828617721574.

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There is no Nobel Prize in astronomy, and perhaps for this reason, historians of science have rarely examined the astronomical sciences from the perspective of the Nobel Prize system. And yet, since the establishment of this system many astronomers and astrophysicists have been nominated for the physics prize and these nominations provide the historian with valuable sources for understanding the dynamical relationship between astronomy and physics during the twentieth century. Apart from giving a general account of the role of astronomy in a Nobel context, this paper investigates a select number of scientists who contributed to astronomy and its allied sciences and were nominated for a Nobel Prize. The focus is on the period from about 1950 to 1966, but earlier nominations of, for example, M. Saha, H. N. Russell, and A. Eddington are also considered.
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7

Peebles, P. James E. "The Future of Astronomy and Physical Cosmology." Publications of the Astronomical Society of Australia 21, no. 4 (2004): 385–89. http://dx.doi.org/10.1071/as04054.

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AbstractAstronomy and cosmology have a substantial observational and theoretical basis, but our standard model still depends on some working assumptions. I comment on the nature of the issues behind these assumptions, the guidance we might find from past resolutions of such issues, and the models we might consider for the future of research in this subject.
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8

Schawinski, Kevin, M. Dennis Turp, and Ce Zhang. "Exploring galaxy evolution with generative models." Astronomy & Astrophysics 616 (August 2018): L16. http://dx.doi.org/10.1051/0004-6361/201833800.

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Context. Generative models open up the possibility to interrogate scientific data in a more data-driven way. Aims. We propose a method that uses generative models to explore hypotheses in astrophysics and other areas. We use a neural network to show how we can independently manipulate physical attributes by encoding objects in latent space. Methods. By learning a latent space representation of the data, we can use this network to forward model and explore hypotheses in a data-driven way. We train a neural network to generate artificial data to test hypotheses for the underlying physical processes. Results. We demonstrate this process using a well-studied process in astrophysics, the quenching of star formation in galaxies as they move from low-to high-density environments. This approach can help explore astrophysical and other phenomena in a way that is different from current methods based on simulations and observations.
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9

Gilmore, Gerard. "The Science of Galaxy Formation." Proceedings of the International Astronomical Union 4, S254 (2008): 487–96. http://dx.doi.org/10.1017/s1743921308028032.

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AbstractOur knowledge of the Universe remains discovery-led: in the absence of adequate physics-based theory, interpretation of new results requires a scientific methodology. Commonly, scientific progress in astrophysics is motivated by the empirical success of the “Copernican Principle”, that the simplest and most objective analysis of observation leads to progress. A complementary approach tests the prediction of models against observation. In practise, astrophysics has few real theories, and has little control over what we can observe. Compromise is unavoidable. Advances in understanding complex non-linear situations, such as galaxy formation, require that models attempt to isolate key physical properties, rather than trying to reproduce complexity. A specific example is discussed, where substantial progress in fundamental physics could be made with an ambitious approach to modelling: simulating the spectrum of perturbations on small scales.
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Leeuw, Lerothodi L., Dominik A. Riechers, John M. Carpenter, Mattia Negrello, and Rob J. Ivison. "Molecular Gas and Star-formation in Selected H-ATLAS SDP Lensed SMGs." Proceedings of the International Astronomical Union 8, S292 (2012): 192. http://dx.doi.org/10.1017/s1743921313001051.

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AbstractWe present detections of spatially resolved CO(J = 2→1) and CO(J = 3→2) emission, respectively, from the lensed submillimeter (submm) galaxies (SMGs), ID 9 (z = 1.577) and ID 17b (z = 2.308), found in the Science Demonstration Phase (SDP) of the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS, www.h-atlas.org). The detections were obtained using the Combined Array for Research in Millimeter-wave Astronomy (CARMA, www.mmarray.org) and confirm redshifts of the lensed galaxies. We exploit the CARMA data together with existing high-J observations, to determine, among other physical properties of the lensed SMGs, the CO line luminosities, brightness temperature ratios, gas masses, and spatial sizes.
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Russell, Monica. "Deep Simplicity: Chaos, Complexity and the Emergence of Life." Pacific Conservation Biology 13, no. 1 (2007): 75. http://dx.doi.org/10.1071/pc070075a.

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The book Deep Simplicity is an introduction to chaos theory and the complex systems of the world. This book explains many concepts and physical laws associated with natural systems in a simple way. The author, Dr. John Gribbin, graduated with a degree in astrophysics from the University of Cambridge and is currently a visiting Fellow in astronomy at the University of Sussex. He has worked for the science journal Nature and the magazine New Scientist (for which he is now a physics consultant); some of his books include In search of Schr�dinger?s Cat (1984). In Search of the Big Bang (1986) and Fate of the Universe (1987).
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12

Pretzl, Klaus. "Cryogenic detectors exploring new phenomena in physics and astrophysics." Europhysics News 52, no. 3 (2021): 18–21. http://dx.doi.org/10.1051/epn/2021303.

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The potential to measure small energy transfers with very high energy resolutions motivated the development of cryogenic detectors to search for dark matter in the universe, the neutrino mass, neutrinoless double beta decay, and new phenomena in astrophysics. Other fields like material and life sciences also benefited from these developments.
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13

Naýryzbaeva, R. F. "Issues Related to Science in the Quran." Iasaýı ýnıversıtetіnіń habarshysy 4, no. 118 (2020): 64–73. http://dx.doi.org/10.47526/2020/2664-0686.036.

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There is no doubt that a person and a people with a strong spiritual support have a great future. Therefore, the scientific study of the Quran is of great importance. The theoretical foundations of this problem are relevant both in the history of religious studies and the philosophy of religion, as well as in the scientific field of natural science and the humanities. Considering the Islamic worldview from the point of view of the humanities, natural (physical) and other sciences allows young people to delve into all areas of science without understanding religion, the Koran as a dogmatic Secret doctrine, and initiates becoming a member of a spiritually conscious society. The article considers The Holy Quran as a divine book based on science, knowledge, teaching and education. The Quran covers all areas of science. In other words, the Quran contains a lot of information from various fields of science: physics, astronomy, astrophysics, chemistry, biology, mathematics, medicine, Economics, Pedagogy, Psychology, Embryology, Geology, Philosophy, Cultural studies, Natural science, Religious studies, and many others. Therefore, the Quran is a source of inexhaustible science. As science and technology develop, the truth of the Quran is also confirmed. The article notes that the Koran is a real book that has not lost its value over the centuries, its wonders are inexhaustible, useful for the happiness and prosperity of all mankind. The connection between the subject of physics and the topics contained in the Koran, sacred words, verses, and prayers is also considered.
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Naýryzbaeva, R. F. "Issues Related to Science in the Quran." Iasaýı ýnıversıtetіnіń habarshysy 4, no. 118 (2020): 64–73. http://dx.doi.org/10.47526/2020/2664-0686.036.

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There is no doubt that a person and a people with a strong spiritual support have a great future. Therefore, the scientific study of the Quran is of great importance. The theoretical foundations of this problem are relevant both in the history of religious studies and the philosophy of religion, as well as in the scientific field of natural science and the humanities. Considering the Islamic worldview from the point of view of the humanities, natural (physical) and other sciences allows young people to delve into all areas of science without understanding religion, the Koran as a dogmatic Secret doctrine, and initiates becoming a member of a spiritually conscious society. The article considers The Holy Quran as a divine book based on science, knowledge, teaching and education. The Quran covers all areas of science. In other words, the Quran contains a lot of information from various fields of science: physics, astronomy, astrophysics, chemistry, biology, mathematics, medicine, Economics, Pedagogy, Psychology, Embryology, Geology, Philosophy, Cultural studies, Natural science, Religious studies, and many others. Therefore, the Quran is a source of inexhaustible science. As science and technology develop, the truth of the Quran is also confirmed. The article notes that the Koran is a real book that has not lost its value over the centuries, its wonders are inexhaustible, useful for the happiness and prosperity of all mankind. The connection between the subject of physics and the topics contained in the Koran, sacred words, verses, and prayers is also considered.
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15

TURYSHEV, SLAVA G., ULF E. ISRAELSSON, MICHAEL SHAO, et al. "SPACE-BASED RESEARCH IN FUNDAMENTAL PHYSICS AND QUANTUM TECHNOLOGIES." International Journal of Modern Physics D 16, no. 12a (2007): 1879–925. http://dx.doi.org/10.1142/s0218271807011760.

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Space offers unique experimental conditions and a wide range of opportunities to explore the foundations of modern physics with an accuracy far beyond that of ground-based experiments. Space-based experiments today can uniquely address important questions related to the fundamental laws of Nature. In particular, high-accuracy physics experiments in space can test relativistic gravity and probe the physics beyond the Standard Model; they can perform direct detection of gravitational waves and are naturally suited for investigations in precision cosmology and astroparticle physics. In addition, atomic physics has recently shown substantial progress in the development of optical clocks and atom interferometers. If placed in space, these instruments could turn into powerful high-resolution quantum sensors greatly benefiting fundamental physics. We discuss the current status of space-based research in fundamental physics, its discovery potential, and its importance for modern science. We offer a set of recommendations to be considered by the upcoming National Academy of Sciences' Decadal Survey in Astronomy and Astrophysics. In our opinion, the Decadal Survey should include space-based research in fundamental physics as one of its focus areas. We recommend establishing an Astronomy and Astrophysics Advisory Committee's interagency "Fundamental Physics Task Force" to assess the status of both ground- and space-based efforts in the field, to identify the most important objectives, and to suggest the best ways to organize the work of several federal agencies involved. We also recommend establishing a new NASA-led interagency program in fundamental physics that will consolidate new technologies, prepare key instruments for future space missions, and build a strong scientific and engineering community. Our goal is to expand NASA's science objectives in space by including "laboratory research in fundamental physics" as an element in the agency's ongoing space research efforts.
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Cusin, Giulia, Irina Dvorkin, Cyril Pitrou, and Jean-Philippe Uzan. "Stochastic gravitational wave background anisotropies in the mHz band: astrophysical dependencies." Monthly Notices of the Royal Astronomical Society: Letters 493, no. 1 (2019): L1—L5. http://dx.doi.org/10.1093/mnrasl/slz182.

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ABSTRACT We show that the anisotropies of the astrophysical stochastic gravitational wave background in the mHz band have a strong dependence on the modelling of galactic and sub-galactic physics. We explore a wide range of self-consistent astrophysical models for stellar evolution and for the distribution of orbital parameters, all calibrated such that they predict the same number of resolved mergers to fit the number of detections during LIGO/Virgo O1 + O2 observations runs. We show that different physical choices for the process of black hole (BH) collapse and cut-off in the BH mass distribution give fractional differences in the angular power spectrum of anisotropies of up to 50 per cent on all angular scales. We also point out that the astrophysical information which can be extracted from anisotropies is complementary to the isotropic background and individual mergers. These results underline the interest in the anisotropies of the stochastic gravitational wave background as a new and potentially rich field of research, at the cross-road between astrophysics and cosmology.
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Xue, Chao, Jian-Ping Liu, Qing Li, et al. "Precision measurement of the Newtonian gravitational constant." National Science Review 7, no. 12 (2020): 1803–17. http://dx.doi.org/10.1093/nsr/nwaa165.

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Abstract The Newtonian gravitational constant G, which is one of the most important fundamental physical constants in nature, plays a significant role in the fields of theoretical physics, geophysics, astrophysics and astronomy. Although G was the first physical constant to be introduced in the history of science, it is considered to be one of the most difficult to measure accurately so far. Over the past two decades, eleven precision measurements of the gravitational constant have been performed, and the latest recommended value for G published by the Committee on Data for Science and Technology (CODATA) is (6.674 08 ± 0.000 31) × 10−11 m3 kg−1 s−2 with a relative uncertainty of 47 parts per million. This uncertainty is the smallest compared with previous CODATA recommended values of G; however, it remains a relatively large uncertainty among other fundamental physical constants. In this paper we briefly review the history of the G measurement, and introduce eleven values of G adopted in CODATA 2014 after 2000 and our latest two values published in 2018 using two independent methods.
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SKIMANTE, K., Ieglitid EGLITIS, N. JEKABSONS, et al. "Observations of astronomical objects using radio (Irbene RT-32 telescope) and optical (Baldone Schmidt) methods." Astronomical and Astrophysical Transactions, Vol. 32, No. 1, Volume 32, Numéro 1 (September 1, 2020): 13–22. http://dx.doi.org/10.17184/eac.4392.

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Institute of Astronomy (University of Latvia) with Ventspils International Radio Astronomy Centre (Ventspils University of Applied Sciences) participation is implementing the scientific project "Complex investigations of the small bodies in the Solar system" which is related to the research of the small bodies in the Solar system (mainly focusing on asteroids and comets) using methods of radio and optical astronomy and signal processing.To detect the rotation period and other physical characteristics of NEO objects using optical methods, 566 positions and photo-metric observations of NEO objects 2006 VB14 = Y5705 = 345705 (hereafter 2006 VB14) and 1986 DA = 6178 (hereafter 1986 DA) were obtained with Baldone Schmidt telescope in 2018. A Fourier transform was applied to determine the rotation period for asteroid 1986 DA. Value 3.12 0.02 h was obtained. Observations confirm the previously obtained rotation period P = 3.25 h for 2006 VB14. To detect weak (~0.1 Jy) OH maser of astronomical objects using radio methods, a researcher group in VIRAC adapted Irbene RT-32 radio telescope working at 1665.402 and 1667.359 MHz frequencies. Novel data processing methods were used to acquire weak signals. Spectral analysis using Fourier transform and continuous wavelet transform were applied to radio astronomical data from multiple observations related to weak OH maser detection. Successful observations of multiple galactic masers were carried out in 2019 and adapted Irbene RT32 radio telescope is ready for the observations of comets in the near future.
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MARBURGER, JOHN H. "SPACE-BASED SCIENCE AND THE AMERICAN COMPETITIVENESS INITIATIVE." International Journal of Modern Physics D 16, no. 12a (2007): 1927–32. http://dx.doi.org/10.1142/s0218271807011553.

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I discuss the process by which science contributes to the setting of government priorities, and how these priorities get translated into programs and budgets at the federal agencies that fund scientific research. New technologies are now opening exciting scientific opportunities across the biological and physical sciences. I review the motivations and goals of President Bush's American Competitiveness Initiative (ACI), the importance of societal relevance to federal investments in basic research, and the ACI's impacts on discovery-oriented disciplines within the physical sciences.
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Colgate, Stirling A. "Relationship between high-energy physical phenomena on the sun and in astrophysics." Solar Physics 118, no. 1-2 (1988): 1–15. http://dx.doi.org/10.1007/bf00148586.

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North, John D. "Book Review: Astronomy as a Model?, Astronomy as a Model for the Sciences in Early Modern Times." Journal for the History of Astronomy 39, no. 4 (2008): 532–34. http://dx.doi.org/10.1177/002182860803900410.

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22

Spinoglio, Luigi, Juan A. Fernández-Ontiveros, and Sabrina Mordini. "Unveiling the physical processes that regulate galaxy evolution with SPICA observations." Proceedings of the International Astronomical Union 15, S356 (2019): 17–22. http://dx.doi.org/10.1017/s1743921320002495.

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AbstractTo study the dust obscured phase of the galaxy evolution during the peak of the Star Formation Rate (SFR) and the Black Hole Accretion Rate (BHAR) density functions (z = 1–4), rest frame mid-to-far infrared (IR) spectroscopy is needed. At these frequencies, dust extinction is at its minimum and a variety of atomic and molecular transitions, tracing most astrophysical domains, occur. The future IR space telescope mission, SPICA, fully redesigned with its 2.5m mirror cooled down to T < 8K, will be able to perform such observations. With SPICA, we will: 1) obtain a direct spectroscopic measurement of the SFR and of the BHAR histories, 2) measure the evolution of metals and dust to establish the matter cycle in galaxies, 3) uncover the feedback and feeding mechanisms in large samples of distant galaxies, either AGN- or starburst-dominated, reaching lookback times of nearly 12 Gyr. SPICA large-area deep surveys will provide low-resolution, mid-IR spectra and continuum fluxes for unbiased samples of tens of thousands of galaxies, and even the potential to uncover the youngest, most luminous galaxies in the first few hundred million years. In this paper a brief review of the scientific preparatory work that has been done in extragalactic astronomy by the SPICA Consortium will be given.
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Hamidi, Zety Sharizat, N. N. M. Shariff, and C. Monstein. "The Development of Solar Astronomy in Malaysia." International Letters of Chemistry, Physics and Astronomy 38 (September 2014): 46–55. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.38.46.

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Monitoring the Sun reveals a variety of fascinating and complex physical phenomena which are being studied mainly by analyzing its emission. Solar activity has an impact with space weather. The characteristic features of the climate of Malaysia are uniform temperature, very high humidity and copious rainfall. It has an average of temperature of 26.7 °C. Therefore, it is suitable to monitor the Sun. In following work, we will emphasize the development of solar astronomy in Malaysia. The ground based observation (i) optical and (ii) radio are the main region that we focused on. Optical observation has started earlier comparing with radio observation. In optical region it covers from 400 – 700 nm while in radio region, we focus from 45 MHz to 870 MHz. The number of observatories is increasing. A dedicated work to understand the Sun activity in radio region is a part of an initiative of the United Nations together with NASA in order to support developing countries participating in „Western Science‟ research. Realize how important for us to keep doing a research about the solar bursts, by using the new radio spectrometer, CALLISTO (Compound Low Cost Low Frequency Transportable Observatories) spectrometer. Malaysia is one of the earliest country from South-East Asia (ASEAN) that involve this research. One of the advantages to start the solar monitoring in Malaysia is because our strategic location as equator country that makes possible to observing a Sun for 12 hours daily throughout a year. We strongly believe that Malaysia as one of contributor of solar activity data through E-CALLISTO network. This is a very good start for developing a radio astronomy in Malaysia. With the implementation of 45 MHz - 870 MHz CALLISTO systems and development of solar burst monitoring network, a new wavelength regime is becoming available for solar radio astronomy. Overall, this article presents an overview of optical and radio astronomy in Malaysia. With the present level of the international collaboration, it is believed that the potential involvement of local and international scientist in solar astrophysics will increase.
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Martínez-Pinedo, G. "Selected topics in nuclear astrophysics." European Physical Journal Special Topics 156, no. 1 (2008): 123–49. http://dx.doi.org/10.1140/epjst/e2008-00611-5.

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Longair, Malcolm. "Radio astronomy and the rise of high-energy astrophysics two anniversaries." International Journal of Modern Physics D 28, no. 02 (2019): 1930004. http://dx.doi.org/10.1142/s0218271819300040.

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This paper celebrates the 100th anniversary of the birth of Martin Ryle and the 50th anniversary of the discovery of pulsars by Jocelyn Bell and Antony Hewish. Ryle and Hewish received the 1974 Nobel Prize in Physics, the first in the area of astrophysics. Their interests strongly overlapped, one of the key papers on the practical implementation of the technique of aperture synthesis being co-authored by Ryle and Hewish. The discovery of pulsars and the roles played by Hewish and Bell are described. These key advances were at the heart of the dramatic rise of high-energy astrophysics in the 1960s and led to the realization that general relativity is central to the understanding of high-energy astrophysical phenomena.
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Mann, Ingrid, Pavel Spurný, Jack Baggaley, et al. "Commission 22: Meteors, Meteorites & Interplanetary Dust." Proceedings of the International Astronomical Union 1, T26A (2005): 167–70. http://dx.doi.org/10.1017/s1743921306004455.

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There have been three international meetings where the subject area of the meeting was to significant extent within the area of interest of commission 22. These were: The Meteoroids 2004 Conference was held at the University of Western Ontario in London, Canada from August 15 to 21, 2004. This conference was the fifth in a series of meteoroid meetings which have been held approximately every three years since 1992, the previous one being in Kiruna, Sweden in 2001. Ingrid Mann chaired a scientific organizing committee which set the program for the conference. The meeting brought together scientists from more than twenty countries, to deliver 84 oral and 38 poster presentations. The papers represented the research contributions of more than 150 different scientists. The conference provided a comprehensive overview of leading edge research on topics ranging from the dynamics, sources and distribution of meteoroids, their chemistry and their physical processes in the interplanetary medium and the Earthõs atmosphere, and space and laboratory studies of meteorites, micrometeorites and interplanetary dust were also well represented. It was clear from the conference that the coordinated international campaigns for the Leonid showers provided a rich observational dataset and lead to the development of new observational and analysis techniques. Another trend obvious at the conference was the increasing use of sophisticated large aperture radars for meteor studies. High performance computing facilitates both dynamical model calculations and sophisticated ablation models. Significant progress was reported on ablation models for meteoroids ranging from dust to those producing bright fireballs. Study of solid particles entering the solar system from interstellar space and improved dust measuring capabilities on interplanetary spacecraft are an important research area which links astrophysical dust with solar system dust. The majority of papers presented at the conference (a total of 69 papers) are being published as a special issue of the journal Earth, Moon, and Planets (Vol. 95, Nos. 1–4) and also in the form of an associated book published by Springer: Modern Meteor Science: An Interdisciplinary View which was edited by R.Hawkes, I. Mann and P. Brown (ISBN 1-4020-4374-0). The book will be accompanied by a CD-ROM which includes a selection of conference photographs and the complete abstracts of all papers from the conference. As is reflected in the title of the spin-off book, this field is becoming increasingly interdisciplinary in nature, with researchers from astronomy, astrophysics, space science, space engineering, cosmochemistry, atmospheric science and geophysics, as well as others, now contributing to research in the field.
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Goudfrooij, Paul, and Ginevra Trinchieri. "The Nature of the Dusty Ionized Gas in NGC 5846: (And Other Elliptical Galaxies ?)." Symposium - International Astronomical Union 186 (1999): 199. http://dx.doi.org/10.1017/s0074180900112598.

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We present new optical imagery and ROSAT HRI X-ray imagery of the elliptical galaxy NGC 5846. A filamentary dust lane is detected in its central region, with a morphology strikingly similar to that observed for the optical nebulosity and the X-ray emission (cf. Fig. 1). A physical connection between the different phases of the interstellar medium therefore seems likely. The energy deposited from the hot gas into heating of the dust grains is consistent with the temperature distribution of the X-ray-emitting gas, which is found to be lowest in the dusty regions. The optical extinction of the dust is consistent with the Galactic extinction curve. We argue that the dust as well as the optical nebulosity are products of an interaction with a small, gas-rich galaxy, not remnants of a cooling flow. A full account of this work is currently in press in Astronomy and Astrophysics, and a preprint is available through http://www.stsci.edu/science/preprints/prep1191/prep1191.html.
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Fanelli, C., L. Origlia, E. Oliva, et al. "Stellar population astrophysics (SPA) with the TNG." Astronomy & Astrophysics 645 (December 22, 2020): A19. http://dx.doi.org/10.1051/0004-6361/202039397.

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Context. High-resolution spectroscopy in the near-infrared (NIR) is a powerful tool for characterising the physical and chemical properties of cool-star atmospheres. The current generation of NIR echelle spectrographs enables the sampling of many spectral features over the full 0.9–2.4 μm range for a detailed chemical tagging. Aims. Within the Stellar Population Astrophysics Large Program at the TNG, we used a high-resolution (R = 50 000) NIR spectrum of Arcturus acquired with the GIANO-B echelle spectrograph as a laboratory to define and calibrate an optimal line list and new diagnostic tools to derive accurate stellar parameters and chemical abundances. Methods. We inspected several hundred NIR atomic and molecular lines to derive abundances of 26 different chemical species, including CNO, iron-group, alpha, Z-odd, and neutron-capture elements. We then performed a similar analysis in the optical using Arcturus VLT-UVES spectra. Results. Through the combined NIR and optical analysis we defined a new thermometer and a new gravitometer for giant stars, based on the comparison of carbon (for the thermometer) and oxygen (for the gravitometer) abundances, as derived from atomic and molecular lines. We then derived self-consistent stellar parameters and chemical abundances of Arcturus over the full 4800–24 500 Å spectral range and compared them with previous studies in the literature. We finally discuss a number of problematic lines that may be affected by deviations from thermal equilibrium and/or chromospheric activity, as traced by the observed variability of He I at 10 830 Å.
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Mendillo, Michael. "The Appearance of the Medicean Moons in 17thCentury Charts and Books—How Long Did It Take?" Proceedings of the International Astronomical Union 6, S269 (2010): 33–41. http://dx.doi.org/10.1017/s1743921310007246.

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AbstractGalileo's talents in perspective andchiaroscurodrawing led to his images of the Moon being accepted relatively quickly as the naturalistic portrayal of a truly physical place. In contrast to his resolved views of the Moon, Galileo saw the satellites of Jupiter as only points of light (as with stars). He thus used star symbols inSidereus Nuncius(1610) for the moons, in constrast to an open disk for Jupiter. In this paper, I describe methods used in subsequent decades to portray objects that could not be seen in any detail but whose very existence challenged the scholastic approach to science. Within fifty years, the existence of the moons was such an accepted component of astronomy that they were depicted in the highly decorative “textbook”Atlas Coelestis seu Harmonia Macrocosmicaby Andreas Cellarius (1660). Other symbolic methods, ranging from the routine to the dramatic, were used in subsequent centuries to portray the moons. Actual photographs using ground-based telescopes were not possible until the 20thcentury, just years before cameras on spaceflight missions captured the true details of the Medicean Stars.
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Karshenboim, S. G., and E. Peik. "Astrophysics, atomic clocks and fundamental constants." European Physical Journal Special Topics 163, no. 1 (2008): 1–7. http://dx.doi.org/10.1140/epjst/e2008-00805-9.

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31

Wahsner, R. "Physical means of cognition and physical reality." Astronomische Nachrichten: A Journal on all Fields of Astronomy 307, no. 5 (1986): 351. http://dx.doi.org/10.1002/asna.2113070537.

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32

Mastichiadis, Apostolos, Ioulia Florou, Elina Kefala, Stella S. Boula, and Maria Petropoulou. "A roadmap to hadronic supercriticalities: a comprehensive study of the parameter space for high-energy astrophysical sources." Monthly Notices of the Royal Astronomical Society 495, no. 2 (2020): 2458–74. http://dx.doi.org/10.1093/mnras/staa1308.

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ABSTRACT Hadronic supercriticalities are radiative instabilities that appear when large amounts of energy are stored in relativistic protons. When the proton energy density exceeds some critical value, a runaway process is initiated resulting in the explosive transfer of the proton energy into electron–positron pairs and radiation. The runaway also leads to an increase of the radiative efficiency, namely the ratio of the photon luminosity to the injected proton luminosity. We perform a comprehensive study of the parameter space by investigating the onset of hadronic supercriticalities for a wide range of source parameters (i.e. magnetic field strengths of 1 G−100 kG and radii of 1011−1016 cm) and maximum proton Lorentz factors (103−109). We show that supercriticalities are possible for the whole range of source parameters related to compact astrophysical sources, like gamma-ray bursts and cores and jets of active galactic nuclei. We also provide an in-depth look at the physical mechanisms of hadronic supercriticalities and show that magnetized relativistic plasmas are excellent examples of non-linear dynamical systems in high-energy astrophysics.
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33

Picquenot, A., F. Acero, J. Bobin, P. Maggi, J. Ballet, and G. W. Pratt. "Novel method for component separation of extended sources in X-ray astronomy." Astronomy & Astrophysics 627 (July 2019): A139. http://dx.doi.org/10.1051/0004-6361/201834933.

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In high-energy astronomy, spectro-imaging instruments such as X-ray detectors allow investigation of the spatial and spectral properties of extended sources including galaxy clusters, galaxies, diffuse interstellar medium, supernova remnants, and pulsar wind nebulae. In these sources, each physical component possesses a different spatial and spectral signature, but the components are entangled. Extracting the intrinsic spatial and spectral information of the individual components from this data is a challenging task. Current analysis methods do not fully exploit the 2D-1D (x, y, E) nature of the data, as spatial information is considered separately from spectral information. Here we investigate the application of a blind source separation (BSS) algorithm that jointly exploits the spectral and spatial signatures of each component in order to disentangle them. We explore the capabilities of a new BSS method (the general morphological component analysis; GMCA), initially developed to extract an image of the cosmic microwave background from Planck data, in an X-ray context. The performance of the GMCA on X-ray data is tested using Monte-Carlo simulations of supernova remnant toy models designed to represent typical science cases. We find that the GMCA is able to separate highly entangled components in X-ray data even in high-contrast scenarios, and can extract the spectrum and map of each physical component with high accuracy. A modification of the algorithm is proposed in order to improve the spectral fidelity in the case of strongly overlapping spatial components, and we investigate a resampling method to derive realistic uncertainties associated to the results of the algorithm. Applying the modified algorithm to the deep Chandra observations of Cassiopeia A, we are able to produce detailed maps of the synchrotron emission at low energies (0.6–2.2 keV), and of the red- and blueshifted distributions of a number of elements including Si and Fe K.
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34

Cappi, Alberto. "The Cosmology of Edgar Allan Poe." Proceedings of the International Astronomical Union 5, S260 (2009): 315–20. http://dx.doi.org/10.1017/s1743921311002468.

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AbstractEureka is a “prose poem” published in 1848, where Edgar Allan Poe presents his original cosmology. While starting from metaphysical assumptions, Poe develops an evolving Newtonian model of the Universe which has many and non casual analogies with modern cosmology. Poe was well informed about astronomical and physical discoveries, and he was influenced by both contemporary science and ancient ideas. For these reasons, Eureka is a unique synthesis of metaphysics, art and science.
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35

Hallett, J. T., D. E. Shemansky, and X. Liu. "A Rotational‐Level Hydrogen Physical Chemistry Model for General Astrophysical Application." Astrophysical Journal 624, no. 1 (2005): 448–61. http://dx.doi.org/10.1086/428935.

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36

Felber, Hans-Joachim. "B. STEPHENSON: Kepler's physical astronomy. Studies in the History of Mathematics and Physical Sciences, Vol. 13. Springer-Verlag New York, Berlin, Heidelberg. London. Paris, Tokyo 1987, 217 Seiten. Preis: DM 118,-. ISBN 0-387-96541-6." Astronomische Nachrichten: A Journal on all Fields of Astronomy 311, no. 2 (1990): 132. http://dx.doi.org/10.1002/asna.2113110213.

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37

Bernabei, R. "Physics and Astrophysics with low background scintillators." European Physical Journal Special Topics 163, no. 1 (2008): 207–26. http://dx.doi.org/10.1140/epjst/e2008-00821-9.

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38

Aliotta, M. "Experimental nuclear astrophysics with radioactive ion beams." European Physical Journal Special Topics 150, no. 1 (2007): 201–6. http://dx.doi.org/10.1140/epjst/e2007-00304-7.

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39

Deka-Szymankiewicz, B., A. Niedzielski, M. Adamczyk, M. Adamów, G. Nowak, and A. Wolszczan. "The Penn State - Toruń Centre for Astronomy Planet Search stars." Astronomy & Astrophysics 615 (July 2018): A31. http://dx.doi.org/10.1051/0004-6361/201731696.

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Context. Our knowledge of the intrinsic parameters of exoplanets is as precise as our determinations of their stellar hosts parameters. In the case of radial velocity searches for planets, stellar masses appear to be crucial. But before estimating stellar masses properly, detailed spectroscopic analysis is essential. With this paper we conclude a general spectroscopic description of the Pennsylvania-Toruń Planet Search (PTPS) sample of stars. Aims. We aim at a detailed description of basic parameters of stars representing the complete PTPS sample. We present atmospheric and physical parameters for dwarf stars observed within the PTPS along with updated physical parameters for the remaining stars from this sample after the first Gaia data release. Methods. We used high resolution (R = 60 000) and high signal-to-noise-ratio (S/N = 150–250) spectra from the Hobby-Eberly Telescope and its High Resolution Spectrograph. Stellar atmospheric parameters were determined through a strictly spectroscopic local thermodynamic equilibrium analysis (LTE) of the equivalent widths of Fe I and Fe II lines. Stellar masses, ages, and luminosities were estimated through a Bayesian analysis of theoretical isochrones. Results. We present Teff, log g, [Fe/H], microturbulence velocities, absolute radial velocities, and rotational velocities for 156 stars from the dwarf sample of PTPS. For most of these stars these are the first determinations. We refine the definition of PTPS subsamples of stars (giants, subgiants, and dwarfs) and update the luminosity classes for all PTPS stars. Using available Gaia and HIPPARCOS parallaxes, we redetermine the stellar parameters (masses, radii, luminosities, and ages) for 451 PTPS stars. Conclusions. The complete PTPS sample of 885 stars is composed of 132 dwarfs, 238 subgiants, and 515 giants, of which the vast majority are of roughly solar mass; however, 114 have masses higher than 1.5 M⊙ and 30 of over 2 M⊙. The PTPS extends toward much less metal abundant and much more distant stars than other planet search projects aimed at detecting planets around evolved stars; 29% of our targets belong to the Galactic thick disc and 2% belong to the halo.
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40

Burchell, Mark J. "W(h)ither the Drake equation?" International Journal of Astrobiology 5, no. 3 (2006): 243–50. http://dx.doi.org/10.1017/s1473550406003107.

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For over 40 years the formalism known as the Drake equation has helped guide speculation about the likelihood of intelligent extraterrestrial life contacting us. Since the equation was formulated there have been significant advances in astronomy and astrophysics, sufficient to merit a review of the significance of the Drake equation. The equation itself is as a series of terms which, when combined, allow an informed discussion of the likelihood of contact with an alien intelligence. However, whilst it has a mathematical form (i.e. a series of terms multiplied together to give an overall probability) it is best understood not as an equation in the strictly mathematical sense. Some of the terms have a physically quantifiable, numerically based meaning (e.g. obtainable from astronomy) and some are more social in content in that they describe the behaviour and evolution of societies and thus are more social science in nature and not truly estimable without observation of a set of societies. Initially, almost all the terms had to be estimated based on informed guesswork or belief. However, in the intervening period since the early 1960s, many of the a priori scientific terms which were themselves initially so uncertain as to require estimation by guess work or belief are now, or will soon be, directly measurable from current or planned astronomical projects. This leaves the non-scientific terms as a distinct class of their own, still subject to analysis only by discussion. Thus observational astronomy has nearly caught up with parts of the Drake equation and will soon quantify the purely physical science parts of the equation. The social parts (concerning intelligent societies, etc.) are still a priori unknowable. In addition, the growth of the subject called astrobiology (i.e. the study of life in the Universe) has developed so fast that communicating with intelligent life is now increasingly seen as just one small part of a much larger discipline. The knowledge as to whether there is life per se (apart from on Earth) in our galactic neighbourhood may be obtainable in the near future directly from observation. Such knowledge will have a profound impact on mankind and will be obtained without the form of communication envisaged by the Drake equation.
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41

Krafft, C., and A. Volokitin. "Interaction of suprathermal solar wind electron fluxes with sheared whistler waves: fan instability." Annales Geophysicae 21, no. 7 (2003): 1393–403. http://dx.doi.org/10.5194/angeo-21-1393-2003.

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Abstract. Several in situ measurements performed in the solar wind evidenced that solar type III radio bursts were some-times associated with locally excited Langmuir waves, high-energy electron fluxes and low-frequency electrostatic and electromagnetic waves; moreover, in some cases, the simultaneous identification of energetic electron fluxes, Langmuir and whistler waves was performed. This paper shows how whistlers can be excited in the disturbed solar wind through the so-called "fan instability" by interacting with energetic electrons at the anomalous Doppler resonance. This instability process, which is driven by the anisotropy in the energetic electron velocity distribution along the ambient magnetic field, does not require any positive slope in the suprathermal electron tail and thus can account for physical situations where plateaued reduced electron velocity distributions were observed in solar wind plasmas in association with Langmuir and whistler waves. Owing to linear calculations of growth rates, we show that for disturbed solar wind conditions (that is, when suprathermal particle fluxes propagate along the ambient magnetic field), the fan instability can excite VLF waves (whistlers and lower hybrid waves) with characteristics close to those observed in space experiments.Key words. Space plasma physics (waves and instabilities) – Radio Science (waves in plasma) – Solar physics, astrophysics and astronomy (radio emissions)
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42

Sandford, S. A., and L. J. Allamandola. "The physical and infrared spectral properties of CO2 in astrophysical ice analogs." Astrophysical Journal 355 (May 1990): 357. http://dx.doi.org/10.1086/168770.

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43

Cowie, Lennox L., and Antoinette Songaila. "Astrophysical Limits on the Evolution of Dimensionless Physical Constants over Cosmological Time." Astrophysical Journal 453 (November 1995): 596. http://dx.doi.org/10.1086/176422.

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44

Squire, Jonathan, and Philip F. Hopkins. "Physical models of streaming instabilities in protoplanetary discs." Monthly Notices of the Royal Astronomical Society 498, no. 1 (2020): 1239–51. http://dx.doi.org/10.1093/mnras/staa2311.

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ABSTRACT We develop simple, physically motivated models for drag-induced dust–gas streaming instabilities, which are thought to be crucial for clumping grains to form planetesimals in protoplanetary discs. The models explain, based on the physics of gaseous epicyclic motion and dust–gas drag forces, the most important features of the streaming instability and its simple generalization, the disc settling instability. Some of the key properties explained by our models include the sudden change in the growth rate of the streaming instability when the dust-to-gas mass ratio surpasses one, the slow growth rate of the streaming instability compared to the settling instability for smaller grains, and the main physical processes underlying the growth of the most unstable modes in different regimes. As well as providing helpful simplified pictures for understanding the operation of an interesting and fundamental astrophysical fluid instability, our models may prove useful for analysing simulations and developing non-linear theories of planetesimal growth in discs.
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45

Maia, Francisco F. S., João F. C. Santos, Wagner J. B. Corradi, and Andrés E. Piatti. "Open cluster characterization via cross-correlation with a spectral library." Proceedings of the International Astronomical Union 5, S266 (2009): 458–61. http://dx.doi.org/10.1017/s1743921309991694.

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AbstractWe present a characterization method based on spectral cross-correlation to obtain the physical parameters of the controversial stellar aggregate ESO442–SC04. The data used was obtained with GMOS at the Gemini South telescope, and includes spectra of 17 stars in the central region of the object and 6 standard stars. fxcor was used iteratively to obtain self-consistent radial velocities for the standard stars and average radial velocities for the science spectra. Spectral types, effective temperatures, surface gravities and metallicities were determined using fxcor to correlate cluster spectra with the ELODIE spectral library and select the best correlation matches using the Tonry & Davis ratio. Analysis of the results suggests that the stars in ESO442–SC04 are not bound and, therefore, they do not constitute a physical system.
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46

STAMATIKOS, MICHAEL. "GRB ASTROPHYSICS IN THE SWIFT ERA AND BEYOND." International Journal of Modern Physics D 18, no. 10 (2009): 1567–70. http://dx.doi.org/10.1142/s0218271809015631.

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Gamma-ray Bursts (GRBs) are relativistic cosmological beacons of transient high energy radiation whose afterglows span the electromagnetic spectrum. Theoretical expectations of correlated neutrino emission position GRBs at an astrophysical nexus for a metamorphosis in our understanding of the Cosmos. This new dawn in the era of experimental (particle) astrophysics and cosmology is afforded by current facilities enabling the novel astronomy of high energy neutrinos, in concert with unprecedented electromagnetic coverage. In that regard, GRBs represent a compelling scientific theme that may facilitate fundamental breakthroughs in the context of Swift, Fermi and IceCube. Scientific synergy will be achieved by leveraging the combined sensitivity of contemporaneous ground-based and satellite observatories, thus optimizing their collective discovery potential. Hence, the advent of GRB multi-messenger astronomy may cement an explicit connection to fundamental physics, via nascent cosmic windows, throughout the next decade.
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47

Padovani, Paolo. "Towards a VO compliant ESO science archive." Proceedings of the International Astronomical Union 2, no. 14 (2006): 585. http://dx.doi.org/10.1017/s1743921307011830.

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Data centres have a major role in the Virtual Observatory (VO), as they are the primary source of astronomical data. The VO cannot (and does not) dictate how a data centre handles its own archive. However, ‘VO-layer’ is needed to ‘translate’ any locally defined parameter to the standard (i.e., International Virtual Observatory Alliance compliant) ones. The longer term vision of the VO is also to hide away any observatory/telescope/instrument specific detail and work in astronomical units, for example, ‘wavelength range’ and not grism or filter name. Data providers are then advised to systematically collect metadata (‘data about data’) about the curation process, assign unique identifiers, describe the general content (e.g., physical coverage) of a collection, and provide interface and capability parameters of public services. Finally, the VO will work at its best with high-level (‘science-ready’) data, so that the VO user is spared as much as possible any complex and time consuming data reduction. Data centres should then make an effort to provide such data.
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48

Figueiredo, Fernando B., and João Fernandes. "José Monteiro da Rocha (1734–1819) and His 1782 Work on the Determination of Comet Orbits." Journal for the History of Astronomy 51, no. 4 (2020): 461–81. http://dx.doi.org/10.1177/0021828620947844.

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In 1782 José Monteiro da Rocha, astronomer and professor at the University of Coimbra, presented, in a public session of the Royal Academy of Sciences of Lisbon, a memoire on the problem of the determination of the orbits of comets. Only in 1799 would the “ Determinação das Orbitas dos Cometas” (Determination of the orbits of comets) be published in the Academy’s memoires. In that work, Monteiro da Rocha presents a method for solving the problem of the determination of the parabolic orbit of a comet making use of three observations. Monteiro da Rocha’s method is essentially the same as the method proposed by Olbers and published under von Zach’s sponsorship 2 years before, in 1797. Having been written and published in Portuguese was certainly a hindrance for its dissemination among the international astronomical community. In this paper, we intend to present Monteiro da Rocha’s method and try to explain to what extent we can justify Gomes Teixeira’s assertion that Monteiro da Rocha and Olbers must figure together in the history of astronomy, as the first inventors of a practical and easy method for the determination of parabolic orbits of comets.
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Belyaev, Vadim S., Anatoly P. Matafonov, and Boris V. Zagreev. "Investigations of the physical nature of the emergence and spread of relativistic astrophysical jets." International Journal of Modern Physics D 27, no. 10 (2018): 1844002. http://dx.doi.org/10.1142/s0218271818440029.

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A series of experiments were carried out at the TSNIIMASH laser facility “Neodym” with a radiation power of 10 TW and an intensity of [Formula: see text]–[Formula: see text][Formula: see text]W/cm2 to simulate the formation and development of astrophysical relativistic jets. It was shown that proton beams are emitted symmetrically in the forward and backward directions to the normal of the target surface. The maximum energy of fast protons and electrons was 5 and 8[Formula: see text]MeV, respectively. At energies in the 0.8–1.7[Formula: see text]MeV range, the ring structures of proton beams are clearly distinguishable with an angular divergence in the range of 3–250. The numerical magnetohydrodynamic calculations have shown that such laboratory experiments can simulate the formation of astrophysical jets with an anomalously small divergence. Moreover, such a plasma stream can form a distinct circular structure. These structures also can be explained as Alfven vortex solitons formed under the conditions of a quasi-stationary superstrong ([Formula: see text]100 MG) magnetic field spontaneously generated in laser produced plasma. It is shown that this model can be used as a model of astrophysical relativistic jets.
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Gangopadhyay, Gautam. "Hundred years of the Saha equation and astrophysics." European Physical Journal Special Topics 230, no. 2 (2021): 495–503. http://dx.doi.org/10.1140/epjs/s11734-021-00005-3.

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