• S. M. Chitre

      Articles written in Journal of Astrophysics and Astronomy

    • Convective instability in the solar envelope

      D. Narasimha S. K. Pandey S. M. Chitre

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      The characteristics of the most unstable fundamental mode and the first harmonic excited in the convection zone of a variety of solar envelope models are shown to be in reasonable agreement with the observed features of granulation and supergranulation.

    • The role of proton cyclotron emission near acereting magnetic neutron stars

      K. M. V. Apparao S. M. Chitre M. J. Rees

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      The process of coherent and incoherent protonn cyyclotron emission occurring near the polar regions of a strongly magnetic accreting neutron star is considered. The soft X-ray flux resulting from the incoherent emission process is calculated for application to Her X-1 and also to gamma ray bursts, a consequence of which is that gamma ray bursts will be accompanied by soft X-ray bursts.

    • Faster-than-light motion in quasars

      J. V. Narlikar S. M. Chitre

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      Over the past fifteen years, observations of some quasars with the techniques of very-long-baseline interferometry have shown that the angular separation between pairs of radio-emitting regions in their cores is increasing year after year. If the quasars are indeed as far away as implied by Hubble’s law, then these angular motions translate into linear speeds several times the speed of light. Several theoretical scenarios have been proposed to show that the observed motions are illusory. The leading contender in this field — the relativistic beam model — and an alternative offered by the concept of a gravitational screen are described and compared in the light of recent observational data.

    • Straight Arc in abell 2390

      D. Narasimha S. M. Chitre

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      The straight arc in the galaxy-cluster Abell 2390 is investigated in the framework of a gravitational lens model that invokes a single background source galaxy. An extended source galaxy at a redshift of 0.913 is being marginally lensed by the foreground X-ray cluster of galaxies at a redshift of 0.231. It is demonstrated that a single lensed galaxy lying on or very near to the lip caustic of the cluster lens is capable of reproducing the linear morphology with the observed breaks.

    • Perspectives on the interior of the Sun

      S. M. Chitre

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      The interior of the Sun is not directly accessible to observations. Nonetheless, it is possible to infer the physical conditions inside the Sun with the help of structure equations governing its equilibrium and with the powerful observational tools provided by the neutrino fluxes and oscillation frequencies. The helioseismic data show that the internal constitution of the Sun can be adequately represented by a standard solar model. It turns out that a cooler solar core is not a viable solution for the measured deficit of neutrino fluxes, and the resolution of the solar neutrino puzzle should be sought in the realm of particle physics.

    • Helioseismic search for magnetic field in the solar interior

      H. M. Antia S. M. Chitre M. J. Thompson

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      The observed splittings of solar oscillation frequencies can be utilized to study possible large-scale magnetic fields present in the solar interior. Using the GONG data on frequency splittings an attempt is made to infer the strength of magnetic fields inside the Sun.

  • Journal of Astrophysics and Astronomy | News

    • Continuous Article Publication

      Posted on January 27, 2016

      Since January 2016, the Journal of Astrophysics and Astronomy has moved to Continuous Article Publishing (CAP) mode. This means that each accepted article is being published immediately online with DOI and article citation ID with starting page number 1. Articles are also visible in Web of Science immediately. All these have helped shorten the publication time and have improved the visibility of the articles.

    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

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