ArticlesArchiveAboutEditorial BoardAuthor Guidelines
Call for papersThe 2026 special issue on Climate & Health is open for submissions.Learn more
International Journal of Astronomy and Astrophysics (IJAA) is an international scientific journal dedicated to the publication and public discussion of high quality original research in all the fields of astrophysics and space sciences and related technology. All the manuscripts must be prepared in English and are sub…
Abraham P. Mahtessian, Garen S. Karapetian, Martik A. Hovhannisyan, Lazar A. Mahtessian
In this work, a computer optimization model has been developed that allows one to load the initial data of observations of supernovae 1a into a table and, in simple steps, by searching for the best fit between observations and theory, obtain the values of the…
Bruce Hoeneisen
In the warm dark matter scenario, the Press-Schechter formalism is valid only for galaxy masses greater than the “velocity dispersion cut-off”. In this work we extend the predictions to masses below the velocity dispersion cut-off, and thereby address the “Mi…
Lorenzo Zaninetti
New solutions, for the stationary and temporary states, are derived for the 1D diffusion of cosmic rays in the presence of losses. The new results are applied to the latitude profile of radiation emitted above the galactic plane. Percolation theory for a spir…
Jacques P. Vallée
We compare the observed radial velocity of different arm tracers, taken near the tangent to a spiral arm. A slight difference is predicted by the density wave theory, given the shock predicted at the entrance to the inner spiral arm. In many of these spiral a…
Bruce Hoeneisen
Warm dark matter has, by definition, a velocity dispersion. Let v hms ( a )= v hms (1)/ a be the root-mean-square velocity of non-relativistic warm dark matter particles in the early universe at expansion parameter a . v hms (1) is an adiabatic invariant. We…
Lorenzo Zaninetti
The Frèchet distribution has aided the modelling of scientific data in many contexts. We demonstrate how it can be adapted to model astrophysical data. We analyze the truncated version of the Frèchet distribution deriving the probability density function (PDF…
Lorenzo Zaninetti
What distribution function best fits that of the stars’ heights above the Galactic plane? Can truncated distributions improve the fit? In order to answer the above questions, we derive the probability density function, the distribution function, the average v…
Jacques P. Vallée
To pinpoint the peak location of the synchrotron total intensity emission in a spiral arm, we use a map of the spiralarm locations (from the observed arm tangent). Thus in a typical spiral arm in Galactic Quadrant I, we find the peak of the synchrotron radiat…
Naser Mostaghel
Through an analytical approach, we show that the Hubble constant is not unique and has two distinct values. The first of these values is consistent with the measurements by Riess et al. , while the second value is consistent with the measurements by the Planc…
Bruce Hoeneisen
The root-mean-square of non-relativistic warm dark matter particle velocities scales as v hrms ( a )= v hrms (1)/ a , where a is the expansion parameter of the universe. This velocity dispersion results in a cut-off of the power spectrum of density fluctuatio…
No articles in this issue.
International Journal of Astronomy and Astrophysics (IJAA) is an international scientific journal dedicated to the publication and public discussion of high quality original research in all the fields of astrophysics and space sciences and related technology. All the manuscripts must be prepared in English and are sub… All articles are open access under a CC BY 4.0 licence, with authors retaining copyright.
Authors submit their manuscript, metadata, and declarations through the portal. There is no submission fee.
The editorial office screens the manuscript for scope, completeness, and formatting before assigning a handling editor.
At least two independent reviewers evaluate the manuscript under single-blind review. Where revisions are required, authors respond point by point.
On acceptance the article processing charge is invoiced and the CC BY 4.0 copyright handover is signed.
The article is copyedited, typeset, and given a DOI, then publishes open access with a permanent link.
Manuscripts must be original and not under consideration elsewhere. Submit in Microsoft Word or LaTeX with figures at 300 dpi minimum. Structure research articles as Abstract, Introduction, Methods, Results, Discussion, and References.
Use the journal's numbered (Vancouver) reference style. Cite sources consecutively in the order they appear, and ensure every reference is complete and retrievable.
Declare all funding sources, conflicts of interest, and ethical approvals (including informed consent and animal-care statements where applicable).