Journal articles: 'Cosmic Explosions'

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Hjorth, Jens, Chryssa Kouveliotou, and Stan Woosley. "Hunting cosmic explosions." Physics World 17, no. 10 (October 2004): 35–39. http://dx.doi.org/10.1088/2058-7058/17/10/31.

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Kulkarni, S. R. "Cosmic Explosions (Optical)." Proceedings of the International Astronomical Union 7, S285 (September 2011): 55–61. http://dx.doi.org/10.1017/s174392131200021x.

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One of the principal motivations of wide-field and synoptic surveys is the search for, and study of, transients. By transients I mean those sources that arise from the background, are detectable for some time, and then fade away to oblivion. Transients in distant galaxies need to be sufficiently bright as to be detectable, and in almost all cases those transients are catastrophic events, marking the deaths of stars. Exemplars include supernovæ and gamma-ray bursts. In our own Galaxy, the transients are strongly variable stars, and in almost all cases are at best cataclysmic rather than catastrophic. Exemplars include flares from M dwarfs, novæ of all sorts (dwarf novæ, recurrent novæ, classical novæ, X-ray novæ) and instabilities in the surface layers of stars such as S Dor or η Carina. In the nearby Universe (say out to the Virgo cluster) we have sufficient sensitivity to see novæ. In 1 I review the history of transients (which is intimately related to the advent of wide-field telescopic imaging). In 2 I summarize wide-field imaging projects, and I then review the motivations that led to the design of the Palomar Transient Factory (PTF). Next comes a summary of the astronomical returns from PTF (3), and that is followed by lessons that I have learnt from PTF (4). I conclude that, during this decade, the study of optical transients will continue to flourish (and may even accelerate as surveys at other wavelengths—notably radio, UV and X-ray—come on-line). Furthermore, it is highly likely that there will be a proliferation of highly-specialized searches for transients. Those searches may well remain active even in the era of LSST (5). I end the article by discussing the importance of follow-up telescopes for transient object studies—a topical issue, given the Portfolio Review that is being undertaken in the US.

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3

Hamuy, Mario. "Cosmic explosions under scrutiny." Nature 480, no. 7377 (December 2011): 328–29. http://dx.doi.org/10.1038/480328a.

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Maslyuh, V. O., and B. I. Hnatyk. "Cosmic rays from hypernovae explosions." Astronomical School’s Report 7, no. 2 (2011): 258–61. http://dx.doi.org/10.18372/2411-6602.07.2258.

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Catanzaro, Michele. "Telescope hunts for cosmic explosions." Physics World 22, no. 05 (May 2009): 7. http://dx.doi.org/10.1088/2058-7058/22/05/10.

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Biermann, Peter L., Philipp P. Kronberg, Michael L. Allen, Athina Meli, and Eun-Suk Seo. "The Origin of the Most Energetic Galactic Cosmic Rays: Supernova Explosions into Massive Star Plasma Winds." Galaxies 7, no. 2 (April 14, 2019): 48. http://dx.doi.org/10.3390/galaxies7020048.

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We propose that the high energy Cosmic Ray particles up to the upturn commonly called the ankle, from around the spectral turn-down commonly called the knee, mostly come from Blue Supergiant star explosions. At the upturn, i.e., the ankle, Cosmic Rays probably switch to another source class, most likely extragalactic sources. To show this we recently compiled a set of Radio Supernova data where we compute the magnetic field, shock speed and shock radius. This list included both Blue and Red Supergiant star explosions; both data show the same magnetic field strength for these two classes of stars despite very different wind densities and velocities. Using particle acceleration theory at shocks, those numbers can be transformed into characteristic ankle and knee energies. Without adjusting any free parameters both of these observed energies are directly indicated by the supernova data. In the next step in the argument, we use the Supernova Remnant data of the starburst galaxy M82. We apply this analysis to Blue Supergiant star explosions: The shock will race to their outer edge with a magnetic field that is observed to follow over several orders of magnitude B ( r ) × r ∼ c o n s t . , with in fact the same magnetic field strength for such stellar explosions in our Galaxy, and other galaxies including M82. The speed is observed to be ∼0.1 c out to about 10 16 cm radius in the plasma wind. The Supernova shock can run through the entire magnetic plasma wind region at full speed all the way out to the wind-shell, which is of order parsec scale in M82. We compare and identify the Cosmic Ray spectrum in other galaxies, in the starburst galaxy M82 and in our Galaxy with each other; we suggest how Blue Supergiant star explosions can provide the Cosmic Ray particles across the knee and up to the ankle energy range. The data from the ISS-CREAM (Cosmic Ray Energetics and Mass Experiment at the International Space Station) mission will test this cosmic ray concept which is reasonably well grounded in two independent radio supernova data sets. The next step in developing our understanding will be to obtain future more accurate Cosmic Ray data near to the knee, and to use unstable isotopes of Cosmic Ray nuclei at high energy to probe the “piston” driving the explosion. We plan to incorporate these data with the physics of the budding black hole which is probably forming in each of these stars.

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de Souza, R. S., E. E. O. Ishida, J. L. Johnson, D. J. Whalen, and A. Mesinger. "Detectability of the first cosmic explosions." Monthly Notices of the Royal Astronomical Society 436, no. 2 (October 16, 2013): 1555–63. http://dx.doi.org/10.1093/mnras/stt1680.

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Smartt, Stephen J. "Cosmic explosions in the young Universe." Nature 491, no. 7423 (October 31, 2012): 205–6. http://dx.doi.org/10.1038/nature11643.

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Melott, Adrian L., and Brian C. Thomas. "From Cosmic Explosions to Terrestrial Fires?" Journal of Geology 127, no. 4 (July 2019): 475–81. http://dx.doi.org/10.1086/703418.

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Wheeler, J. Craig. "Astrophysical explosions: from solar flares to cosmic gamma-ray bursts." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 370, no. 1960 (February 13, 2012): 774–99. http://dx.doi.org/10.1098/rsta.2011.0351.

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Astrophysical explosions result from the release of magnetic, gravitational or thermonuclear energy on dynamical time scales, typically the sound-crossing time for the system. These explosions include solar and stellar flares, eruptive phenomena in accretion discs, thermonuclear combustion on the surfaces of white dwarfs and neutron stars, violent magnetic reconnection in neutron stars, thermonuclear and gravitational collapse supernovae and cosmic gamma-ray bursts, each representing a different type and amount of energy release. This paper summarizes the properties of these explosions and describes new research on thermonuclear explosions and explosions in extended circumstellar media. Parallels are drawn between studies of terrestrial and astrophysical explosions, especially the physics of the transition from deflagration-to-detonation.

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O'Brien, P., and P. Jonker. "Studying stellar explosions with Athena." Proceedings of the International Astronomical Union 11, A29B (August 2015): 243. http://dx.doi.org/10.1017/s1743921316005147.

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AbstractAthena is the second large mission selected in the ESA Cosmic Vision plan. With its large collecting area, high spectral-energy resolution (X-IFU instrument) and impressive grasp (WFI instrument), Athena will truly revolutionise X-ray astronomy. The most prodigious sources of high-energy photons are often transitory in nature. Athena will provide the sensitivity and spectral resolution coupled with rapid response to enable the study of the dynamic sky. Potential sources include: distant Gamma-Ray Bursts to probe the reionisation epoch and find missing baryons in the cosmic web; tidal disruption events to reveal dormant supermassive and intermediate-mass black holes; and supernova explosions to understand progenitors and their environments. We illustrate Athenas capabilities and show how it will be able to constrain the nature of explosive transients including gas metallicity and dynamics.

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Hinton, J. A., and R. L. C. Starling. "High-energy emission from transients." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 371, no. 1992 (June 13, 2013): 20120279. http://dx.doi.org/10.1098/rsta.2012.0279.

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Cosmic explosions dissipate energy into their surroundings on a very wide range of time scales: producing shock waves and associated particle acceleration. The historical culprits for the acceleration of the bulk of Galactic cosmic rays are supernova remnants: explosions on approximately 10 4 year time scales. Increasingly, however, time-variable emission points to rapid and efficient particle acceleration in a range of different astrophysical systems. Gamma-ray bursts have the shortest time scales, with inferred bulk Lorentz factors of approximately 1000 and photons emitted beyond 100 GeV, but active galaxies, pulsar wind nebulae and colliding stellar winds are all now associated with time-variable emission at approximately teraelectron volt energies. Cosmic photons and neutrinos at these energies offer a powerful probe of the underlying physical mechanisms of cosmic explosions, and a tool for exploring fundamental physics with these systems. Here, we discuss the motivations for high-energy observations of transients, the current experimental situation, and the prospects for the next decade, with particular reference to the major next-generation high-energy observatory, the Cherenkov Telescope Array.

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13

Diehl, Roland. "Gamma-ray observations of cosmic nuclei." EPJ Web of Conferences 260 (2022): 10001. http://dx.doi.org/10.1051/epjconf/202226010001.

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Gamma rays from nuclear processes such as radioactive decay and de-excitations are among the most-direct tools to witness the production and existence of speciﬁc nuclei and isotopes in and near cosmic nucleosynthesis sites. With space-borne instrumentation such as NuSTAR and SPI/INTEGRAL, and experimental techniques to handle a substantial instrumental background from cosmic-ray activations of the spacecraft and instrument, unique results have been obtained, from diffuse emissions of nuclei and positrons in interstellar surroundings of sources, as well as from observations of cosmic explosions and their radioactive afterglows. These witness non-sphericity in supernova explosions and a ﬂow of nucleosynthesis ejecta through superbubbles as common source environments. Next-generation experiments that are awaiting space missions promise a next level of observational nuclear astrophysics.

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Kasliwal, M. M. "Systematically Bridging the Gap Between Novae and Supernovae." Publications of the Astronomical Society of Australia 29, no. 4 (2012): 482–88. http://dx.doi.org/10.1071/as11061.

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AbstractThe venerable study of cosmic explosions is over a century old. However, until recently, there has existed a glaring six-magnitude luminosity gap between the brightest novae and faintest supernovae. Serendipitous discoveries, archival searches and ongoing systematic surveys are yielding optical transients that are fainter, faster and rarer than supernovae. Theorists predict a variety of mechanisms to produce transients in the gap and observers have the best chance of finding them in the local Universe. Here I review the discoveries and the unique physics of cosmic explosions that bridge this gap between novae and supernovae.

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de Ugarte Postigo, Antonio, Christina C. Thöne, Antonia Rowllinson, Rubén García Benito, Andrew J. Levan, Javier Gorosabel, Paolo Goldoni, and Steve Schulze. "First spectroscopy of a short-hard GRB: the environment of a compact object merger." Proceedings of the International Astronomical Union 10, S313 (September 2014): 398–99. http://dx.doi.org/10.1017/s1743921315002616.

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AbstractShort gamma-ray bursts (GRBs) are an extremely elusive family of cosmic explosions. They are thought to be related to the violent merger of compact objects (such as a neutron stars or black holes). Their optical counterparts were not discovered until 2005, and since then, there had been no successful spectroscopic observations. Here we present the first spectra of a short GRB, which we use to study the environment and derive implications on the progenitors of these cosmic explosions. This poster is based on the work by de Ugarte Postigoet al. (2014).

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Kasliwal, Mansi M. "Systematically Bridging the Gap between Novae and Supernovae." Proceedings of the International Astronomical Union 7, S281 (July 2011): 9–16. http://dx.doi.org/10.1017/s1743921312014585.

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AbstractThe venerable study of cosmic explosions is over a century old. However, until recently, there has existed a glaring six-magnitude luminosity gap between the brightest novae and faintest supernovae. To find optical transients that are fainter, faster, and rarer than supernovae, we designed a systematic search: the Palomar Transient Factory. Theorists predict a variety of mechanisms to produce transients in the gap and observers have the best chance of finding them in the local universe. Here I present discoveries and unique physics of cosmic explosions that bridge this gap between novae and supernovae.

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17

KUSENKO, ALEXANDER. "COSMIC CONNECTIONS: FROM COSMIC RAYS TO GAMMA RAYS, COSMIC BACKGROUNDS AND MAGNETIC FIELDS." Modern Physics Letters A 28, no. 02 (January 20, 2013): 1340001. http://dx.doi.org/10.1142/s0217732313400014.

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Combined data from gamma-ray telescopes and cosmic-ray detectors have produced some new surprising insights regarding intergalactic and galactic magnetic fields, as well as extragalactic background light. We review some recent advances, including a theory explaining the hard spectra of distant blazars and the measurements of intergalactic magnetic fields based on the spectra of distant sources. Furthermore, we discuss the possible contribution of transient galactic sources, such as past gamma-ray bursts and hypernova explosions in the Milky Way, to the observed flux of ultrahigh-energy cosmic-rays nuclei. The need for a holistic treatment of gamma rays, cosmic rays, and magnetic fields serves as a unifying theme for these seemingly unrelated phenomena.

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Bendre, Abhijit B., Detlef Elstner, and Oliver Gressel. "On the combined role of cosmic rays and supernova-driven turbulence for galactic dynamos." Monthly Notices of the Royal Astronomical Society 500, no. 3 (November 12, 2020): 3527–35. http://dx.doi.org/10.1093/mnras/staa3509.

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ABSTRACT Large-scale coherent magnetic fields observed in the nearby galaxies are thought to originate by a mean-field dynamo. This is governed via the turbulent electromotive force (EMF, $\overline{{\boldsymbol {\cal E}} {}}$) generated by the helical turbulence driven by supernova (SN) explosions in the differentially rotating interstellar medium (ISM). In this paper, we aim to investigate the possibility of dynamo action by the virtue of buoyancy due to a cosmic ray (CR) component injected through the SN explosions. We do this by analysing the magnetohydrodynamic simulations of local shearing box of ISM in which the turbulence is driven via random SN explosions and the energy of the explosion is distributed in the CR and/or thermal energy components. We use the magnetic field aligned diffusion prescription for the propagation of CR. We compare the evolution of magnetic fields in the models with the CR component to our previous models that did not involve the CR. We demonstrate that the inclusion of CR component enhances the growth of dynamo slightly. We further compute the underlying dynamo coefficients using the test-field method and argue that the entire evolution of the large-scale mean magnetic field can be reproduced with an α − Ω dynamo model. We also show that the inclusion of CR component leads to an unbalanced turbulent pumping between magnetic field components and additional dynamo action by the Rädler effect.

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Deschamps, Frédéric, and Fabrice Mottez. "From Cosmic Explosions to Terrestrial Fires? A Discussion." Journal of Geology 128, no. 4 (July 2020): 389–91. http://dx.doi.org/10.1086/709750.

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Melott, Adrian L., and Brian C. Thomas. "From Cosmic Explosions to Terrestrial Fires? A Reply." Journal of Geology 128, no. 4 (July 2020): 393. http://dx.doi.org/10.1086/709751.

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21

Shiga, David. "Gas clouds may have created biggest cosmic explosions." New Scientist 211, no. 2827 (August 2011): 13. http://dx.doi.org/10.1016/s0262-4079(11)62063-0.

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22

Kaper, Lex. "Gamma-ray bursts: the most powerful cosmic explosions." Symposium - International Astronomical Union 212 (2003): 106–14. http://dx.doi.org/10.1017/s0074180900211704.

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With the detection of gamma-ray burst (GRB) afterglows, the cosmological origin of GRBs has been firmly established. Recent observations suggest that (long-duration) GRBs are due to the collapse of a massive star forming a black hole. Besides theoretical arguments, observational evidence supporting this hypothesis comes from the coincidence of several GRBs with a supernova. Also, all accurately located GRBs are contained in the optical (restframe UV) extent of distant, blue galaxies. Some of these host galaxies show relatively high star-formation rates, which is expected when massive stars and GRBs are physically linked. Alternatively, GRBs can be produced by the merging of a binary neutron star system, such as the Hulse-Taylor binary pulsar. Very likely GRBs trace the massive-star populations in distant galaxies. With their enormous brightness, GRBs are powerful probes of the early universe, providing information on the properties of their host galaxies, the cosmic star-formation history, and potentially the first generations of massive stars.

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Biermann, Peter L., Julia Becker Tjus, Wim de Boer, Laurenţiu I. Caramete, Alessandro Chieffi, Roland Diehl, Iris Gebauer, et al. "Supernova explosions of massive stars and cosmic rays." Advances in Space Research 62, no. 10 (November 2018): 2773–816. http://dx.doi.org/10.1016/j.asr.2018.03.028.

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Kasliwal, Mansi M. "Systematically Bridging the Gap between Novæ and Supernovæ." Proceedings of the International Astronomical Union 7, S285 (September 2011): 62. http://dx.doi.org/10.1017/s1743921312000221.

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AbstractUntil recently, the venerable field of cosmic explosions has been plagued with a glaring six-magnitude luminosity gap between the brightest novæ and the faintest supernovæ. A key science driver of the Palomar Transient Factory was a systematic search for optical transients that are fainter, faster and rarer than supernovæ. Theorists predict a variety of mechanisms to produce transients in that “gap”, and observers have the best chance of finding them in the local universe. The talk presented the discoveries and the unique physics of cosmic explosions which bridge that gap between novæ and supernovæ. As Fig. 1 illustrates, there is now evidence of multiple, distinct populations of rare transients in the “gap”.

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Whalen, Daniel J., Candace C. Joggerst, Chris L. Fryer, Massimo Stiavelli, Alexander Heger, and Daniel E. Holz. "FINDING THE FIRST COSMIC EXPLOSIONS. II. CORE-COLLAPSE SUPERNOVAE." Astrophysical Journal 768, no. 1 (April 17, 2013): 95. http://dx.doi.org/10.1088/0004-637x/768/1/95.

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Whalen, Daniel J., Wesley Even, Lucille H. Frey, Joseph Smidt, Jarrett L. Johnson, C. C. Lovekin, Chris L. Fryer, et al. "FINDING THE FIRST COSMIC EXPLOSIONS. I. PAIR-INSTABILITY SUPERNOVAE." Astrophysical Journal 777, no. 2 (October 18, 2013): 110. http://dx.doi.org/10.1088/0004-637x/777/2/110.

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Dopita, Michael A. "Stellar Feedback Through Cosmic Time: Starbursts & Superwinds." Proceedings of the International Astronomical Union 3, S250 (December 2007): 367–78. http://dx.doi.org/10.1017/s1743921308020711.

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AbstractThroughout cosmic time, the feedback of massive star winds and supernova explosions has been instrumental in determining the phase structure of the interstellar medium, controlling important aspects of both the formation and evolution of galaxies, producing galactic winds and enriching the intergalactic medium with heavy elements. In this paper, I review progress made in our theoretical understanding of how these feedback processes have operated throughout cosmic time from the epoch of the first stars through to the present day.

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Nomoto, Ken'ichi, Keiichi Maeda, Hideyuki Umeda, Takuya Ohkubo, Jingsong Deng, and Paolo Mazzali. "Hypernovae and their nucleosynthesis." Symposium - International Astronomical Union 212 (2003): 395–403. http://dx.doi.org/10.1017/s0074180900212485.

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We review the characteristics of nucleosynthesis in ‘hypernovae’, i.e., core-collapse supernovae with very large explosion energies (≳ 1052 ergs). The hypernova yields show the following characteristics: (i) the mass ratio between the complete and incomplete Si burning regions is larger in hypernovae than normal supernovae. As a result, higher energy explosions tend to produce larger [(Zn, Co, V)/Fe] and smaller [(Mn, Cr)/Fe], which could explain the trend observed in very metal-poor stars; (ii) because of enhanced α-rich freeze-out, 44Ca, 48Ti, and 64Zn are produced more abundantly than in normal supernovae. The large [(Ti, Zn)/Fe] ratios observed in very metal poor stars strongly suggest a significant contribution of hypernovae; and (iii) oxygen burning takes place in more extended regions in hypernovae to synthesize a larger amount of Si, S, Ar, and Ca (‘Si’), which makes the ‘Si’/O ratio larger. The abundance pattern of the starburst galaxy M 82 may be attributed to hypernova explosions. We thus suggest that hypernovae make important contribution to the early Galactic (and cosmic) chemical evolution.

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Sakurai, Kunitomo. "The Source Composition of Galactic Cosmic Rays as Possibly Originated from the Dust in the Circumstellar and Interstellar Space." International Astronomical Union Colloquium 126 (1991): 433–36. http://dx.doi.org/10.1017/s0252921100067257.

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AbstractThe chemical composition of galactic cosmic rays in their sources is similar to that of interstellar clouds or grains which are relatively enriched in refractory and siderophile elements as compared with the chemical composition of the solar atmosphere. Taking into account this fact, it is shown that the cosmic ray source matter can be identified as the dust or grains observed in the envelopes of red supergiant stars or the matter originally ejected from supernova explosions.

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Whalen, Daniel J., Joseph Smidt, Wesley Even, S. E. Woosley, Alexander Heger, Massimo Stiavelli, and Chris L. Fryer. "FINDING THE FIRST COSMIC EXPLOSIONS. III. PULSATIONAL PAIR-INSTABILITY SUPERNOVAE." Astrophysical Journal 781, no. 2 (January 15, 2014): 106. http://dx.doi.org/10.1088/0004-637x/781/2/106.

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Domínguez, Inma, Luciano Piersanti, Eduardo Bravo, Oscar Straniero, and Sergio Cristallo. "Type Ia SN progenitors: pre-explosion phase in nearly Chandrasekhar mass WDs." EPJ Web of Conferences 260 (2022): 06001. http://dx.doi.org/10.1051/epjconf/202226006001.

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Type Ia supernovae are used as distance indicators to measure the expansion rate of the Universe and to constrain the nature of dark energy. Current and upcoming surveys will allow to extend supernova Hubble diagrams to higher redshifts and to improve further their statistics. It is accepted that Type Ia supernovae are thermonuclear explosions of carbon-oxygen white dwarfs in binary systems. However, the identification of their progenitors, the evolutionary path leading to the explosion and the explosion mechanism itself have not been identified yet. This is critical, as we need to understand the potential evolution of their luminosity with cosmic time and, thus, with their stellar progenitors. We will review the current situation, considering observational hints. We will focus on our recent models, that follow the evolution of carbon-oxygen white dwarfs accreting mass up to thermonuclear runaway, and on their dependence with the initial metallicity of the white dwarf progenitors.

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Berger, E., S. R. Kulkarni, G. Pooley, D. A. Frail, V. McIntyre, R. M. Wark, R. Sari, et al. "A common origin for cosmic explosions inferred from calorimetry of GRB030329." Nature 426, no. 6963 (November 2003): 154–57. http://dx.doi.org/10.1038/nature01998.

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Mac Low, Mordecai-Mark. "From Gas to Stars Over Cosmic Time." Science 340, no. 6140 (June 27, 2013): 1229229. http://dx.doi.org/10.1126/science.1229229.

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From the time the first stars formed over 13 billion years ago to the present, star formation has had an unexpectedly dynamic history. At first, the star-formation rate density increased dramatically, reaching a peak 10 billion years ago of more than 10 times the present-day value. Observations of the initial rise in star formation remain difficult, poorly constraining it. Theoretical modeling has trouble predicting this history because of the difficulty in following the feedback of energy from stellar radiation and supernova explosions into the gas from which further stars form. Observations from the ground and space with the next generation of instruments should reveal the full history of star formation in the universe, and simulations appear poised to accurately predict the observed history.

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Cucchiara, Antonino, Mark Rafelski, Michele Fumagalli, Daniel Kocevski, Jason X. Prochaska, Ryan J. Cooke, and G. D. Becker. "Exploring the Environment of the most powerful Explosions." Proceedings of the International Astronomical Union 11, A29B (August 2015): 261–62. http://dx.doi.org/10.1017/s1743921316005251.

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AbstractMore than 60 GRBs at z ≳ 1.5 reside in the vicinity of dense, cold gas as probed by the measured neutral hydrogen via afterglow absorption spectroscopy. We present the largest sample of GRB-DLAs to date in comparison with a sample of DLAs along quasars: the metallicity of the GRB hosts represents a unique tool to understand if this particular subset of galaxies can be the key ingredient for GRB formation (and massive stars) at any redshift as well as the overall cosmic star-formation rate. We show that GRB-DLAs live in a metal enriched environment, especially at z ≳ 4, likely the result of recent intense star formation and/or SNe episodes. We also derive that our metallicity measurements are broadly consistent with a mild metallicity bias for the GRB formation.

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Nagai, Tomoyuki, and Vladimir Vassiliev. "Gamma-ray Observation of Nearby Starburst Galaxy IC342." International Journal of Modern Physics A 20, no. 14 (June 10, 2005): 3167–69. http://dx.doi.org/10.1142/s0217751x05026042.

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Regions with high star formation rates (SFR) in starburst galaxies (SBGs) are frequently accompanied by high density clouds of interstellar matter (ISM). This may create nearly perfect conditions for generating diffuse gamma-ray radiation as high energy cosmic rays accelerated in supernovae explosions of massive progenitor stars interact with the ambient protons. If the current paradigm that supernovae are the origin sites of high energy cosmic rays is valid, then the star forming regions rich in supernovae may become the laboratories to test and study this phenomenon. The gamma-ray luminosity of these extragalactic objects is suppressed by a large distance factor compared to supernovae in our own galaxy. However, flux estimates indicate that if star bursting regions have a proper combination of critical parameters (intersteller medium density, age, size, supernova rate, magnetic field strength) the cumulative enhancement of the gamma-ray luminosity resulting from multiple explosions of supernovae into dense ISM may generate an observable flux for nearby SBGs such as M82, IC342. A search for TeV gamma-ray emission from IC342 was conducted with the Whipple 10m gamma-ray telescope from September 2002 to March 2004.

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Tanaka, Hiroyuki K. M. "Japanese volcanoes visualized with muography." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 377, no. 2137 (December 10, 2018): 20180142. http://dx.doi.org/10.1098/rsta.2018.0142.

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High-energy muons that are generated via the reaction between primary cosmic rays and the Earth's atmosphere can be used to map out the density distribution in shallow parts of a volcano's interior. This new subterranean imaging technique called muography has been applied to three different kinds of volcano dynamics in Japan: lava dome formation, vulcanian explosions and magma convection. Taking all of the observational data together, it appears that muography can serve as a new and alternative volcano observation technique, providing a fresh approach to understanding eruption mechanism. This review describes observational studies in which muography has been used to explore the volcano's interior. This article is part of the Theo Murphy meeting issue ‘Cosmic-ray muography’.

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Fields, Brian D., Adrian L. Melott, John Ellis, Adrienne F. Ertel, Brian J. Fry, Bruce S. Lieberman, Zhenghai Liu, Jesse A. Miller, and Brian C. Thomas. "Supernova triggers for end-Devonian extinctions." Proceedings of the National Academy of Sciences 117, no. 35 (August 18, 2020): 21008–10. http://dx.doi.org/10.1073/pnas.2013774117.

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The Late Devonian was a protracted period of low speciation resulting in biodiversity decline, culminating in extinction events near the Devonian–Carboniferous boundary. Recent evidence indicates that the final extinction event may have coincided with a dramatic drop in stratospheric ozone, possibly due to a global temperature rise. Here we study an alternative possible cause for the postulated ozone drop: a nearby supernova explosion that could inflict damage by accelerating cosmic rays that can deliver ionizing radiation for up to∼100ky. We therefore propose that the end-Devonian extinctions were triggered by supernova explosions at∼20 pc, somewhat beyond the “kill distance” that would have precipitated a full mass extinction. Such nearby supernovae are likely due to core collapses of massive stars; these are concentrated in the thin Galactic disk where the Sun resides. Detecting either of the long-lived radioisotopesSm146orPu244in one or more end-Devonian extinction strata would confirm a supernova origin, point to the core-collapse explosion of a massive star, and probe supernova nucleosynthesis. Other possible tests of the supernova hypothesis are discussed.

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Biermann, P. L. "Cosmic ray particles from exploding massive stars with winds." ASTRA Proceedings 1 (June 27, 2014): 29–31. http://dx.doi.org/10.5194/ap-1-29-2014.

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Abstract. The origin of cosmic rays is still unsettled. Many sources have been proposed over the years, and exploding stars still provide the most promising candidates. Here we examine one of these scenarios, and compare the resulting predictions with data: Massive stars have winds, and when these stars explode, the resulting shock runs through the wind. The observable phenomenon is called radio-supernova, and many have been observed in non-thermal radio emission. This emission allows to determine the magnetic field in the wind as a function of radius, and so allows to check, whether such explosions can achieve the high energies required and also explain the flux and the spectra of cosmic rays. The observations show this to be the case, and so we conclude that radio supernovae can explain the high-energy Galactic cosmic rays over the entire energy range, and that the spectral predictions are compatible with observations.

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Sakurai, K. "The source composition of cosmic rays and its relation to supernova explosions." Advances in Space Research 15, no. 1 (January 1995): 35–40. http://dx.doi.org/10.1016/s0273-1177(99)80121-5.

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Kładoczny, Piotr. "Odgłosy wojny w przekazach prasowych i literackich." Oblicza Komunikacji 10 (November 15, 2018): 9–22. http://dx.doi.org/10.19195/2083-5345.10.1.

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Echoes of war in press and literary accountsThe article is devoted to the names of the sounds whose purpose was to describe the hearing of the war in press and literary texts. There are generic names sound, detonation explosives, the sound of strokes, the sounds of people, and the definition of silence in the texts. The research material allows to distinguish three types of wars: a the modern with the sounds of aircraft and other equipment and explosions of bombs; b the old war with the sounds of the weapons, the screams of people and the sounds of animals, and c the war in the future — cosmic and yet not fully documented.The literary text describes more different situations, including more vocabulary and adjective terms. Press releases, albeit more numerous, have a lower number of different sound names and more modest adjectives.

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WOLFENDALE, ARNOLD. "Risks in space." European Review 11, no. 1 (February 2003): 77–90. http://dx.doi.org/10.1017/s1062798703000097.

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The human species is beset by ‘risks’; one of which is related to its exposed position on the Earth as it travels through cosmic space. An examination is made of the major risks – those associated with cometary impact, with solar emissions and with the explosions of nearby stars. Estimates are given of the risks associated with trying to avoid the effect of these phenomena. Not surprisingly it is concluded that more work is necessary.

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Blandford, R. D. "The Phenomena of High Energy Astrophysics." Symposium - International Astronomical Union 214 (2003): 3–20. http://dx.doi.org/10.1017/s0074180900194124.

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A brief summary of some highlights in the study of high energy astrophysical sources over the past decade is presented. It is argued that the great progress that has been made derives largely from the application of new technology to observation throughout all of the electromagnetic and other spectra and that, on this basis, the next decade should be even more exciting. However, it is imperative to observe cosmic sources throughout these spectra in order to obtain a full understanding of their properties. In addition, it is necessary to learn the universal laws that govern the macroscopic and the microscopic behavior of cosmic plasma over a great range of physical conditions by combining observations of different classes of source. These two injunctions are illustrated by discussions of cosmology, hot gas, supernova remnants and explosions, neutron stars, black holes and ultrarelativistic outflows. New interpreations of the acceleration of Galactic cosmic rays, the cooling of hot gas in rich clusters and the nature of ultrarelativistic outflows are outlined. The new frontiers of VHE γ-ray astronomy, low frequency radio astronomy, neutrino astronomy, UHE cosmic ray physics and gravitational wave astronomy are especially promising.

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Troja, E., C. L. Fryer, B. O’Connor, G. Ryan, S. Dichiara, A. Kumar, N. Ito, et al. "A nearby long gamma-ray burst from a merger of compact objects." Nature 612, no. 7939 (December 7, 2022): 228–31. http://dx.doi.org/10.1038/s41586-022-05327-3.

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AbstractGamma-ray bursts (GRBs) are flashes of high-energy radiation arising from energetic cosmic explosions. Bursts of long (greater than two seconds) duration are produced by the core-collapse of massive stars1, and those of short (less than two seconds) duration by the merger of compact objects, such as two neutron stars2. A third class of events with hybrid high-energy properties was identified3, but never conclusively linked to a stellar progenitor. The lack of bright supernovae rules out typical core-collapse explosions4–6, but their distance scales prevent sensitive searches for direct signatures of a progenitor system. Only tentative evidence for a kilonova has been presented7,8. Here we report observations of the exceptionally bright GRB 211211A, which classify it as a hybrid event and constrain its distance scale to only 346 megaparsecs. Our measurements indicate that its lower-energy (from ultraviolet to near-infrared) counterpart is powered by a luminous (approximately 1042 erg per second) kilonova possibly formed in the ejecta of a compact object merger.

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Sinitsyna, V. G., V. Y. Sinitsyna, and Yu I. Stozhkov. "Galactic Cosmic Rays: The first detection of TeV gamma-rays from Red Dwarfs." EPJ Web of Conferences 208 (2019): 14007. http://dx.doi.org/10.1051/epjconf/201920814007.

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The present point of view on the sources of cosmic rays in Galaxy considers explosions of supernovae as sources of these particles up to energies of 1017 eV. However, the experimental data obtained with Pamela, Fermi, AMS-02 spectrometers requires the existence of nearby sources of cosmic rays at distances less then 1 kpc from the solar system. These sources could explain such experimental data as the growth of the ratio of galactic positrons to electrons with increasing energy, the complex dependence of the exponent of the proton and alpha spectra from the energy of these particles, the appearance of an anomaly component in cosmic rays. We consider active dwarf stars as possible sources of galactic cosmic rays in the energy range up to 1014 eV. These stars produce powerful stellar flares. The generation of high-energy cosmic rays has to be accompanied by high-energy gamma-ray emission. Here we present the SHALON long-term observation data aimed at searching for gamma-ray emission above 800 GeV from active red dwarf stars. The data obtained during more than 10 years observations of the dwarf stars V962 Tau, V780 Tau, V388 Cas and V1589 Cyg were analyzed. The high-energy gamma-ray emission in the TeV energy range, mostly of the flaring type from the sources mentioned above, was detected. This result confirms that active dwarf stars are also the sources of high-energy galactic cosmic rays.

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Hasebe, Nobuyuki, Makoto Hareyama, Satoshi Kodaira, and Kunitomo Sakurai. "Are Galactic Cosmic Rays Accelerated inside the Ejectae Expanding just after Supernova Explosions ?" Nuclear Physics A 758 (July 2005): 292–95. http://dx.doi.org/10.1016/j.nuclphysa.2005.05.051.

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Smidt, Joseph, Daniel J. Whalen, E. Chatzopoulos, Brandon Wiggins, Ke-Jung Chen, Alexandra Kozyreva, and Wesley Even. "FINDING THE FIRST COSMIC EXPLOSIONS. IV. 90–140 $\;{{M}_{\odot }}$ PAIR-INSTABILITY SUPERNOVAE." Astrophysical Journal 805, no. 1 (May 19, 2015): 44. http://dx.doi.org/10.1088/0004-637x/805/1/44.

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Erlykin, A. D., and A. W. Wolfendale. "The anisotropy of galactic cosmic rays as a product of stochastic supernova explosions." Astroparticle Physics 25, no. 3 (April 2006): 183–94. http://dx.doi.org/10.1016/j.astropartphys.2006.01.003.

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Frebel, Anna. "Reconstructing the Cosmic Evolution of the Chemical Elements." Daedalus 143, no. 4 (October 2014): 71–80. http://dx.doi.org/10.1162/daed_a_00307.

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The chemical elements are created in nuclear fusion processes in the hot and dense cores of stars. The energy generated through nucleosynthesis allows stars to shine for billions of years. When these stars explode as massive supernovae, the newly made elements are expelled, chemically enriching the surrounding regions. Subsequent generations of stars are formed from gas that is slightly more element-enriched than that from which previous stars formed. This chemical evolution can be traced back to its beginning soon after the Big Bang by studying the oldest and most metal-poor stars still observable in the Milky Way today. Through chemical analysis, they provide the only available tool for gaining information about the nature of the short-lived first stars and their supernova explosions more than thirteen billion years ago. These events set in motion the transformation of the pristine universe into a rich cosmos of chemically diverse planets, stars, and galaxies.

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Kulpa-Dybeł, K., K. Otmianowska-Mazur, B. Kulesza-Żydzik, G. Kowal, D. Wóltański, M. Hanasz, and K. Kowalik. "Cosmic ray driven dynamo in barred and ringed galaxies." Proceedings of the International Astronomical Union 6, S274 (September 2010): 398–400. http://dx.doi.org/10.1017/s1743921311007368.

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AbstractWe study the global evolution of the magnetic field and interstellar medium (ISM) of the barred and ringed galaxies in the presence of non-axisymmetric components of the potential, i.e. the bar and/or the oval perturbations. The magnetohydrodynamical dynamo is driven by cosmic rays (CR), which are continuously supplied to the disk by supernova (SN) remnants. Additionally, weak, dipolar and randomly oriented magnetic field is injected to the galactic disk during SN explosions. To compare our results directly with the observed properties of galaxies we construct realistic maps of high-frequency polarized radio emission. The main result is that CR driven dynamo can amplify weak magnetic fields up to few μG within few Gyr in barred and ringed galaxies. What is more, the modelled magnetic field configuration resembles maps of the polarized intensity observed in barred and ringed galaxies.

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ZANINETTI, LORENZO. "MODELS OF DIFFUSION OF GALACTIC COSMIC RAYS FROM SUPERBUBBLES." International Journal of Modern Physics A 22, no. 05 (February 20, 2007): 995–1026. http://dx.doi.org/10.1142/s0217751x07035215.

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Superbubbles are shells in the interstellar medium produced by the simultaneous explosions of many supernova remnants. The solutions of the mathematical diffusion and of the Fourier expansion in 1D, 2D and 3D were deduced in order to describe the diffusion of nucleons from such structures. The mean number of visits in the the case of the Levy flights in 1D was computed with a Monte Carlo simulation. The diffusion of cosmic rays has its physical explanation in the relativistic Larmor gyro-radius which is energy dependent. The mathematical solution of the diffusion equation in 1D with variable diffusion coefficient was computed. Variable diffusion coefficient means magnetic field variable with the altitude from the Galactic plane. The analytical solutions allow us to calibrate the code that describes the Monte Carlo diffusion. The maximum energy that can be extracted from the superbubbles is deduced. The concentration of cosmic rays is a function of the distance from the nearest superbubble and the selected energy. The interaction of the cosmic rays on the target material allows us to trace the theoretical map of the diffuse Galactic continuum gamma-rays. The streaming of the cosmic rays from the Gould Belts that contains the sun at its internal was described by a Monte Carlo simulation. Ten new formulas are derived.

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Journal articles on the topic 'Cosmic Explosions'

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