668 citations
Counting papers with at most 25 authors, so collaboration author lists do not stand in for the people here.
- Institute for Research in Fundamental SciencesIR108 papers
- Damghan UniversityIR31 papers
- Islamic Azad University, MashhadIR13 papers
- K. N. Toosi University of TechnologyIR13 papers
- Farhangian UniversityIR12 papers
- Shahid Beheshti UniversityIR11 papers
- University of TehranIR11 papers
- Dublin City UniversityIE10 papers
- Golestan UniversityIR10 papers
- Centre National de la Recherche ScientifiqueFR9 papers
- Deakin UniversityAU9 papers
- Institute of Metal Superplasticity ProblemsRU9 papers
35 papers · 1 filter
Braking indices as probes of r-mode spin-down in young pulsars
Shahram Abbassi, Armin Memarian, Evelyn Sophia Guest +1
We present a timing-based framework for interpreting braking-index measurements in young pulsars using a four-channel spin-down model that includes particle-wind, magnetic-dipole,…
Global Transonic Solution of Hot Accretion Flow with Thermal Conduction
Samik Mitra, Sayyedeh Masoumeh Ghoreyshi, Amin Mosallanezhad +2
We examine the effect of thermal conduction on the low-angular momentum hot accretion flow (HAF) around non-rotating black holes accreting mass at very low rate. While doing so, we…
Self-gravitating collapsing star and black hole spin-up in long gamma ray bursts
Agnieszka Janiuk, Narjes Shahamat Dehsorkh, Dominika Krol
Long Gamma Ray Bursts (GRBs) originate from the collapse of massive, rotating stars. We aim to model the process of stellar collapse in the scenario of a self-gravitating collapsin…
Thermal Conduction in Clumpy Disks and BLR clouds
Hussein Ayad, Maryam Samadi, Shahram Abbassi
We investigate the dynamics of clumps that coexisted with/in advection-dominated accretion flows by considering thermal conductivity. Thermal conduction can be one of the effective…
Global structure and dynamics of slowly rotating accretion flows
Razieh Ranjbar, Amin Mosallanezhad, Shahram Abbassi
We study the global solutions of slowly rotating accretion flows around the supermassive black hole in the nucleus of an elliptical galaxy. The velocity of accreted gas surrounding…
GRB variabilities and following gravitational waves induced by gravitational instability in NDAFs
Narjes Shahamat, Shahram Abbassi, Tong Liu
The present work proposes a new formalism for the inner regions of a neutrino-dominated accretion flows (NDAFs) by considering the self-gravity, where the neutrino opacity is high…
Analytical Solutions of Radiative Transfer Equations in Accretion Discs with Finite Optical Depth
Maryam Samadi, Fahimeh Habibi, Shahram Abbassi
The main purpose of this paper is to obtain analytical solutions for radiative transfer equations related to the vertical structure of accretion discs with finite optical depth. In…
Gravitational radiation by magnetic field: application to millisecond magnetars
Elham Nazari, Mahmood Roshan
We investigate the direct contribution of the magnetic field to the gravitational wave generation. To do so, we study the post-Newtonian energy-momentum tensor of the magnetized fl…
Viscous Evolution of Magnetized Clumps: a Source for X-ray Flares in Gamma-ray Bursts
Narjes Shahamat, Shahram Abbassi
X-ray flares can be accounted for a hint to the late time activity of Gamma-ray bursts (GRBs) central engines. Such a long term activity has been described through some models, one…
Bondi accretion in the finite luminous region of elliptical galaxies
M. Samadi, S. Zangeneh, S. Abbassi
The classical Bondi model is adopted to study accretion onto the finite luminous region around the central massive black hole (MBH) in an elliptical galaxy. Unlike Bondi (1952), we…
Accretion flows with comparable radiation and gas pressures
Maryam Samadi, Shahram Abbassi, Wei-Min Gu
By taking into account photon absorption, we investigate the vertical structure of accretion flows with comparable radiation and gas pressures. We consider two separate energy equa…
Post-Newtonian corrections to Toomre's criterion
Ali Kazemi, Mahmood Roshan, Elham Nazari
The gravitational stability of a two-dimensional self-gravitating and differentially rotating gaseous disk in the context of post-Newtonian (hereafter PN) theory is studied. Using…
Local fragmentation of thin disks in Eddington-inspired gravity
Mahmood Roshan, Ali Kazemi, Ivan De Martino
We find the generalized version of the Toomre's criterion for the stability of a rotating thin disk in the context of Eddington inspired Born-Infeld (EiBI) gravity which possesses…
Fourier analysis of advection-dominated accretion flows
Asiyeh Habibi, Shahram Abbassi, Mohsen Shadmehri
We implement a new semi-analytical approach to investigate radially self-similar solutions for the steady-state advection-dominated accretion flows (ADAFs). We employ the usual …
The effects of toroidal magnetic field on the vertical structure of hot accretion flows
Fatemeh Zahra Zeraatgari, Amin Mosallanezhad, Shahram Abbassi +1
We solved the set of two-dimensional magnetohydrodynamic (MHD) equations for optically thin black hole accretion flows incorporating toroidal component of magnetic field. Following…
Anchoring polar magnetic field in a stationary thick accretion disk
Maryam Samadi, Shahram Abbassi
We investigate the properties of a hot accretion flow bathed in a poloidal magnetic field. We consider an axisymmetric viscous resistive flow in the steady state configuration. We…
Self-Gravity in Magnetized Neutrino-Dominated Accretion Discs
Narjes Shahamat, Shahram Abbassi
What is conducted in the present work is the study of self-gravity effects on vertical structure of magnetized neutrino-dominated accretion disc (termed NDAF and considered as a ce…
The influence of outflow and global magnetic field on the structure and spectrum of resistive CDAFs
Maryam Ghasemnezhad, Shahram Abbassi
We examine the effects of a global magnetic field and outflow on radiatively inefficient accretion flow (RIAF) in the presence of magnetic resistivity. We find a self-similar solut…
The influence of large scale magnetic field in the structure of supercritical accretion flow with outflow
Maryam Ghasemnezhad, Shahram Abbassi
We present the effects of ordered large scale magnetic field on the structure of supercritical accretion flow in the presence of outflow. In the cylindrical coordinates (),…
How does an asymmetric magnetic field change the vertical structure of a hot accretion flow?
Maryam Samadi, Shahram Abbassi, Richard Lovelace
This paper explores the effects of large-scale magnetic fields in hot accretion flows for asymmetric configurations with respect to the equatorial plane. The solutions that we have…
Post-Newtonian Jeans analysis
Elham Nazari, Ali Kazemi, Mahmood Roshan +1
The Jeans analysis is studied in the first post-Newtonian limit. In other words, the relativistic effects on the local gravitational instability are considered for systems where ch…
The influence of outflow in supercritical accretion flows
Fatemeh Zahra Zeraatgari, Shahram Abbassi, Amin Mosallanezhad
We solve the radiation-hydrodynamic (RHD) equations of supercritical accretion flows in the presence of radiation force and outflow by using self similar solutions. Compare with th…
The Effect of Large Scale Magnetic Field on Outflow in ADAFs: an Odd Symmetry Configuration
Maryam Samadi, Shahram Abbassi
We construct self-similar inflow-outflow solutions for a hot viscous-resistive accretion flow with large scale magnetic fields that have odd symmetry with respect to the equatorial…
Hydrodynamical wind on vertically self-gravitating ADAFs in the presence of toroidal magnetic field
Maryam Ghasemnezhad, Shahram Abbassi
We present the effect of a hydrodynamical wind on the structure and the surface temperature of a vertically self-gravitating magnetized ADAFs using self-similar solutions. Also a m…