New Astronomy Reviews最新文献

{"title":"Numerical simulations of jets","authors":"S. Komissarov, O. Porth","doi":"10.1016/J.NEWAR.2021.101610","DOIUrl":"https://doi.org/10.1016/J.NEWAR.2021.101610","url":null,"abstract":"","PeriodicalId":19718,"journal":{"name":"New Astronomy Reviews","volume":null,"pages":null},"PeriodicalIF":6.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84769501","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"15 years of galactic surveys and hard X-ray background measurements","authors":"Roman A. Krivonos ,&nbsp;Antony J. Bird ,&nbsp;Eugene M. Churazov ,&nbsp;John A. Tomsick ,&nbsp;Angela Bazzano ,&nbsp;Volker Beckmann ,&nbsp;Guillaume Bélanger ,&nbsp;Arash Bodaghee ,&nbsp;Sylvain Chaty ,&nbsp;Erik Kuulkers ,&nbsp;Alexander Lutovinov ,&nbsp;Angela Malizia ,&nbsp;Nicola Masetti ,&nbsp;Ilya A. Mereminskiy ,&nbsp;Rashid Sunyaev ,&nbsp;Sergey S. Tsygankov ,&nbsp;Pietro Ubertini ,&nbsp;Christoph Winkler","doi":"10.1016/j.newar.2021.101612","DOIUrl":"10.1016/j.newar.2021.101612","url":null,"abstract":"<div><p>The <em>INTEGRAL</em> hard X-ray surveys have proven to be of fundamental importance. <em>INTEGRAL</em><span><span><span> has mapped the Galactic plane with its large field of view and excellent sensitivity. Such hard X-ray snapshots of the whole </span>Milky Way on a time scale of a year are beyond the capabilities of past and current narrow-FOV </span>grazing incidence X-ray telescopes. By expanding the </span><em>INTEGRAL</em> X-ray survey into shorter timescales, a productive search for transient X-ray emitters was made possible. In more than fifteen years of operation, the <em>INTEGRAL</em> observatory has given us a sharper view of the hard X-ray sky, and provided the triggers for many follow-up campaigns from radio frequencies to gamma-rays. In addition to conducting a census of hard X-ray sources across the entire sky, <em>INTEGRAL</em> has carried out, through Earth occultation manoeuvres, unique observations of the large-scale cosmic X-ray background, which will without question be included in the annals of X-ray astronomy as one of the mission’s most salient contribution to our understanding of the hard X-ray sky.</p></div>","PeriodicalId":19718,"journal":{"name":"New Astronomy Reviews","volume":null,"pages":null},"PeriodicalIF":6.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.newar.2021.101612","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"107318268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The INTEGRAL view of the pulsating hard X-ray sky: from accreting and transitional millisecond pulsars to rotation-powered pulsars and magnetars","authors":"A. Papitto ,&nbsp;M. Falanga ,&nbsp;W. Hermsen ,&nbsp;S. Mereghetti ,&nbsp;L. Kuiper ,&nbsp;J. Poutanen ,&nbsp;E. Bozzo ,&nbsp;F. Ambrosino ,&nbsp;F. Coti Zelati ,&nbsp;V. De Falco ,&nbsp;D. de Martino ,&nbsp;T. Di Salvo ,&nbsp;P. Esposito ,&nbsp;C. Ferrigno ,&nbsp;M. Forot ,&nbsp;D. Götz ,&nbsp;C. Gouiffes ,&nbsp;R. Iaria ,&nbsp;P. Laurent ,&nbsp;J. Li ,&nbsp;D.F. Torres","doi":"10.1016/j.newar.2020.101544","DOIUrl":"10.1016/j.newar.2020.101544","url":null,"abstract":"<div><p><span><span><span><span>In the last 25 years a new generation of X-ray satellites imparted a significant leap forward in our knowledge of X-ray pulsars. The discovery of accreting and transitional millisecond pulsars proved that </span>disk accretion<span> can spin up a neutron star to a very high rotation speed. The detection of MeV-GeV pulsed emission from a few hundreds of rotation-powered pulsars probed </span></span>particle acceleration in the outer </span>magnetosphere<span>, or even beyond. Also, a population of two dozens of magnetars has emerged. </span></span><em>INTEGRAL</em> played a central role to achieve these results by providing instruments with high temporal resolution up to the hard X-ray/soft, <em>γ</em><span>-ray band and a large field of view imager with good angular resolution to spot hard X-ray transients. In this article we review the main contributions by </span><em>INTEGRAL</em> to our understanding of the pulsating hard X-ray sky, such as the discovery and characterization of several accreting and transitional millisecond pulsars, the generation of the first catalog of hard X-ray/soft <em>γ</em>-ray rotation-powered pulsars, the detection of polarization in the hard X-ray emission from the Crab pulsar, and the discovery of persistent hard X-ray emission from several magnetars.</p></div>","PeriodicalId":19718,"journal":{"name":"New Astronomy Reviews","volume":null,"pages":null},"PeriodicalIF":6.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.newar.2020.101544","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79735482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"INTEGRAL View on cataclysmic variables and symbiotic binaries","authors":"Alexander Lutovinov ,&nbsp;Valery Suleimanov ,&nbsp;Gerardo Juan Manuel Luna ,&nbsp;Sergey Sazonov ,&nbsp;Domitilla de Martino ,&nbsp;Lorenzo Ducci ,&nbsp;Victor Doroshenko ,&nbsp;Maurizio Falanga","doi":"10.1016/j.newar.2020.101547","DOIUrl":"10.1016/j.newar.2020.101547","url":null,"abstract":"<div><p><span>Accreting white dwarfs (WDs) constitute a significant fraction of the hard X-ray sources detected by the </span><em>INTEGRAL</em><span><span> observatory. Most of them are magnetic Cataclysmic Variables (CVs) of the intermediate polar (IP) and polar types, but the contribution of the Nova-likes systems and the systems with optically thin boundary layers, </span>Dwarf Novae<span> (DNs) and Symbiotic Binaries (or Symbiotic Stars, SySs) in quiescence is also not negligible. Here we present a short review of the results obtained from the observations of cataclysmic variables and symbiotic binaries by </span></span><em>INTEGRAL</em><span>. The highlight results include the significant increase of the known IP population, determination of the WD mass for a significant fraction of IPs, the establishment of the luminosity function of magnetic CVs, and uncovering origin of the Galactic ridge X-ray emission which appears to largely be associated with hard emission from magnetic CVs.</span></p></div>","PeriodicalId":19718,"journal":{"name":"New Astronomy Reviews","volume":null,"pages":null},"PeriodicalIF":6.0,"publicationDate":"2020-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.newar.2020.101547","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90196245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Steady-state nucleosynthesis throughout the Galaxy","authors":"R. Diehl, M. Krause, K. Kretschmer, M. Lang, Moritz M. M. Pleintinger, T. Siegert, Wei Wang, L. Bouchet, Pierrick Martin","doi":"10.1016/j.newar.2020.101608","DOIUrl":"https://doi.org/10.1016/j.newar.2020.101608","url":null,"abstract":"","PeriodicalId":19718,"journal":{"name":"New Astronomy Reviews","volume":null,"pages":null},"PeriodicalIF":6.0,"publicationDate":"2020-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86966033","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"OB Associations and their origins","authors":"Nicholas J. Wright","doi":"10.1016/j.newar.2020.101549","DOIUrl":"10.1016/j.newar.2020.101549","url":null,"abstract":"<div><p><span><span>OB associations are unbound groups of young stars made prominent by their bright OB members, and have long been thought to be the expanded remnants of dense star clusters. They have been important in astrophysics for over a century thanks to their luminous </span>massive stars<span>, though their low-mass members have not been well studied until the last couple of decades. This has changed thanks to data from X-ray observations, spectroscopic surveys and astrometry from </span></span><em>Gaia</em><span> that allows their full stellar content to be identified and their dynamics to be studied, which in turn is leading to changes in our understanding of these systems and their origins, with the old picture of Blaauw (1964a) now being superseded. It is clear now that OB associations have considerably more substructure than once envisioned, both spatially, kinematically and temporally. These changes have implications for the star formation<span><span> process, the formation and evolution of planetary systems, and the build-up of </span>stellar populations across galaxies.</span></span></p></div>","PeriodicalId":19718,"journal":{"name":"New Astronomy Reviews","volume":null,"pages":null},"PeriodicalIF":6.0,"publicationDate":"2020-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.newar.2020.101549","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80323867","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"INTEGRAL results on the electron-positron annihilation radiation and X-ray & Gamma-ray diffuse emission of the Milky Way","authors":"Eugene Churazov ,&nbsp;Laurent Bouchet ,&nbsp;Pierre Jean ,&nbsp;Elisabeth Jourdain ,&nbsp;Jürgen Knödlseder ,&nbsp;Roman Krivonos ,&nbsp;Jean-Pierre Roques ,&nbsp;Sergey Sazonov ,&nbsp;Thomas Siegert ,&nbsp;Andrew Strong ,&nbsp;Rashid Sunyaev","doi":"10.1016/j.newar.2020.101548","DOIUrl":"10.1016/j.newar.2020.101548","url":null,"abstract":"<div><p>This review summarizes <em>INTEGRAL</em><span> results on two topics: the electron-positron annihilation line and X-ray &amp; Gamma-ray diffuse emission of the Milky Way.</span></p><p>The electron-positron annihilation line at 511 keV is the most prominent spectral feature in the gamma-ray spectrum of the Milky Way. From the observational perspective, <em>INTEGRAL</em> has already provided constraints on the total flux, morphology of the annihilation line distribution, the spectral shape of the line and the strength of the three-photon annihilation continuum. In particular, the most salient morphological feature in the all-sky map of the annihilation emission based on <em>INTEGRAL</em> data is the so-called ”Bulge” component, with the characteristic size of <span><math><mrow><mo>∼</mo><mn>6</mn><mo>−</mo><msup><mn>10</mn><mo>∘</mo></msup></mrow></math></span> and the positrons’ annihilation rate of <span><math><mrow><mo>∼</mo><msup><mn>10</mn><mn>43</mn></msup><mspace></mspace><msup><mi>s</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></math></span><span><span>. A more extended ”Disc” component is also present, although its total luminosity is model dependent. The brightness of the Bulge component compared to the Disc is in contrast with other multi-wavelength images of the Milky Way. The annihilation spectrum consists of a line centered at 511 keV and the ortho-positronium continuum. The strength of the latter indicates that the majority of annihilations go via the positronium formation channel. The shape of the annihilation spectrum is consistent with the assumption that most of the </span>positrons<span> annihilate in a warm and partly ionized medium, although more complicated scenarios are also possible. From the theoretical point of view, a successful model should answer three main questions: (i) physical mechanism(s) responsible for production of positrons, (ii) positrons spatial migration (if any) from the production sites, and (iii) physics of annihilation. Remarkably, despite significant progress provided by </span></span><em>INTEGRAL</em> in the characterization of the Milky Way annihilation emission, the origin of positrons remains an open question. The essence of the problem is the abundance of positron production channels and the uncertainty in the distance positrons can travel before annihilation.</p><p>The spectral-imaging mapping of the Milky Way by <em>INTEGRAL</em><span> provides important constraints on the nature of the Galactic diffuse continuum hard X-rays and soft gamma-rays in the 20 keV – 2  MeV band. Below  ~ 60 keV, numerous unresolved objects (accreting white dwarfs) dominate the flux, but their contribution fades away at higher energies. Models of cosmic-ray induced emission suggest that the dominant diffuse component above  ~ 60 keV (excluding annihilation emission) is inverse Compton scattering<span> from GeV electrons on interstellar radiation fields<span>. Non-thermal bremsstrahlung contributes at a lo","PeriodicalId":19718,"journal":{"name":"New Astronomy Reviews","volume":null,"pages":null},"PeriodicalIF":6.0,"publicationDate":"2020-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.newar.2020.101548","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73341138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"INTEGRAL view of AGN","authors":"Angela Malizia ,&nbsp;Sergey Sazonov ,&nbsp;Loredana Bassani ,&nbsp;Elena Pian ,&nbsp;Volker Beckmann ,&nbsp;Manuela Molina ,&nbsp;Ilya Mereminskiy ,&nbsp;Guillaume Belanger","doi":"10.1016/j.newar.2020.101545","DOIUrl":"10.1016/j.newar.2020.101545","url":null,"abstract":"<div><p><span>AGN<span> are among the most energetic phenomena in the Universe and in the last two decades </span></span><em>INTEGRAL</em>’s contribution in their study has had a significant impact. Thanks to the <em>INTEGRAL</em><span> extragalactic sky surveys<span>, all classes of soft X-ray detected (in the 2-10 keV band) AGN have been observed at higher energies as well. Up to now, around 450 AGN have been catalogued and a conspicuous part of them are either objects observed at high-energies for the first time or newly discovered AGN. The high-energy domain (20-200 keV) represents an important window for spectral studies of AGN and it is also the most appropriate for AGN population studies, since it is almost unbiased against obscuration and therefore free of the limitations which affect surveys at other frequencies. Over the years, </span></span><em>INTEGRAL</em> data have allowed to characterise AGN spectra at high energies, to investigate their absorption properties, to test the AGN unification scheme and to perform population studies. In this review the main results are reported and <em>INTEGRAL</em>’s contribution to AGN science is highlighted for each class of AGN. Finally, new perspectives are provided, connecting <em>INTEGRAL</em>’s science with that at other wavelengths and in particular to the GeV/TeV regime which is still poorly explored.</p></div>","PeriodicalId":19718,"journal":{"name":"New Astronomy Reviews","volume":null,"pages":null},"PeriodicalIF":6.0,"publicationDate":"2020-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.newar.2020.101545","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76695712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The case for jets in cataclysmic variables","authors":"Deanne L. Coppejans ,&nbsp;Christian Knigge","doi":"10.1016/j.newar.2020.101540","DOIUrl":"10.1016/j.newar.2020.101540","url":null,"abstract":"<div><p>For decades cataclysmic variables<span> (CVs) were thought to be one of the few classes of accreting compact objects to not launch jets, and have consequently been used to constrain jet launching models. However, recent theoretical and observational advances indicate that CVs do in fact launch jets. Specifically, it was demonstrated that their accretion-outflow cycle is analogous to that of their higher mass cousins – the X-ray Binaries (XRBs). Subsequent observations of the CV SS Cygni confirmed this and have consistently shown radio flaring equivalent to that in the XRBs that marks a transient jet. Based on this finding and the emission properties, several studies have concluded that the radio emission is most likely from a transient jet. Observations of other CVs, while not conclusive, are consistent with this interpretation. However, the issue is not yet settled. Later observations have raised a number of questions about this model, as well as about potential alternative radio emission mechanisms. CVs are non-relativistic and many have well-determined distances; these properties would make them ideal candidates with which to address many of our outstanding questions about fundamental jet physics. Here we review the case for jets in CVs, discuss the outstanding questions and issues, and outline the future work necessary to conclusively answer the question of whether CVs launch jets.</span></p></div>","PeriodicalId":19718,"journal":{"name":"New Astronomy Reviews","volume":null,"pages":null},"PeriodicalIF":6.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.newar.2020.101540","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74449779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Particle acceleration in astrophysical jets","authors":"James H. Matthews ,&nbsp;Anthony R. Bell ,&nbsp;Katherine M. Blundell","doi":"10.1016/j.newar.2020.101543","DOIUrl":"10.1016/j.newar.2020.101543","url":null,"abstract":"<div><p><span>In this chapter, we review some features of particle acceleration in astrophysical jets. We begin by describing four observational results relating to the topic, with particular emphasis on jets in </span>active galactic nuclei<span> and parallels between different sources. We then discuss the ways in which particles can be accelerated to high energies in magnetised plasmas, focusing mainly on shock acceleration, second-order Fermi and magnetic reconnection; in the process, we attempt to shed some light on the basic conditions that must be met by any mechanism for the various observational constraints to be satisfied. We describe the limiting factors for the maximum particle energy and briefly discuss multimessenger signals from neutrinos and ultrahigh energy cosmic rays, before describing the journey of jet plasma from jet launch to cocoon with reference to the different acceleration mechanisms. We conclude with some general comments on the future outlook.</span></p></div>","PeriodicalId":19718,"journal":{"name":"New Astronomy Reviews","volume":null,"pages":null},"PeriodicalIF":6.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.newar.2020.101543","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80717316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}