Arindam Basu - Academia.edu (original) (raw)

Papers by Arindam Basu

Electron-positronium scattering and doubly excited autodetaching states of the positronium negati... more Electron-positronium scattering and doubly excited autodetaching states of the positronium negative ion AS GHOSH and ARINDAM BASU Department of Theoretical Physics, Indian Association for the Cultivation of Science, 2A&B Raja SC Mullick Road, Jadavpur, Kolkata-700 032, ...

Physical Review A, 2005

ABSTRACT

Physical Review A, 2001

Scattering of a Ps atom off a He target has been investigated in the framework of the close-coupl... more Scattering of a Ps atom off a He target has been investigated in the framework of the close-coupling approximation using two basis sets: (a) Ps(1s)+He(1s 2 ,1s2 1 s,1s2 1 p) and (b) Ps(1s,2p)+He (1s 2 ,1s2 1 s,1s2 1 p). Target inelastic channels reduce the elastic cross sections ...

Physical Review A, 2000

Projectile elastic close-coupling method is employed to investigate the positronium-hydrogen scat... more Projectile elastic close-coupling method is employed to investigate the positronium-hydrogen scattering using different basis sets to find the rate of convergence with added eigenstates and pseudostates. We report s-, p-, and d-wave phase shifts below the first positronium ...

Physical Review A, 2001

Scattering of orthopositronium off helium target has been investigated using close-coupling metho... more Scattering of orthopositronium off helium target has been investigated using close-coupling method in the energy range 0–110 eV. Two basis sets, (a) Ps(1s)+He(1s 2 , 1s2 1 s, 1s2 1 p) and (b) Ps(1s,2p)+He(1s 2 , 1s2 1 s, 1s2 1 p), have been employed to find the scattering ...

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2008

The effect of external environments such as that of plasma on atomic systems are currently intere... more The effect of external environments such as that of plasma on atomic systems are currently interesting topics of research [1], [2] and [3]. Some theoretical studies have been performed to estimate the ground states [1] and [2] and resonant states [3] and [4] of two electron atoms in Debye ...

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2004

Ortho-positronium–ortho-positronium (o-Ps–o-Ps) scattering is investigated using close coupling m... more Ortho-positronium–ortho-positronium (o-Ps–o-Ps) scattering is investigated using close coupling model. The following four basis sets have been employed: (1) Ps(1s) + Ps(1s) (2) Ps(1s,2s,2p ) + Ps(1s,2s,2p) (3) Ps(1s,2s,2 ) + Ps(1s,2s,2 ) and (4) Ps(1s,2s,2 , 3 ) + Ps(1s,2s,2 , 3 ) ...

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2004

Collisions involving atoms and antiatoms have been investigated at low incident energies using cl... more Collisions involving atoms and antiatoms have been investigated at low incident energies using close-coupling approximation (CCA). We investigate ortho-positronium-ortho-positronium (o-Ps-o-Ps) scattering up to incident energy 3.4 eV. Antihydrogen-hydrogen elastic scattering has been studied in the energy range 10 À10 to 10 À2 a.u., whereas antihydrogen-helium system has been investigated in the range 10 À16 to 10 À2 a.u. The s-wave elastic scattering parameters, viz., scattering length, effective range, phase shift, cross section etc., have been reported. The present predictions have been compared with the other corresponding theoretical predictions wherever available. Usefulness of CCA model to investigate these systems at thermal energies has been emphasized.

Journal of Physics B: Atomic, Molecular and Optical Physics, 2004

Page 1. Positronium–alkali atom scattering at medium energies This article has been downloaded fr... more Page 1. Positronium–alkali atom scattering at medium energies This article has been downloaded from IOPscience. Please scroll down to see the full text article. 2004 J. Phys. B: At. Mol. Opt. Phys. 37 1709 (http://iopscience.iop.org/0953-4075/37/8/012) ...

Journal of Physics B: Atomic, Molecular and Optical Physics, 2010

... Opt. Phys. 43 (2010) 115202 A Basu Table 1. The resonance positions and widths for the lowest... more ... Opt. Phys. 43 (2010) 115202 A Basu Table 1. The resonance positions and widths for the lowest lying 1,3Po auto-detaching resonances of H − under various plasma conditions. ... (E r) D in au 30 40 50 60 70 80 90 100 4.0 4.4 4.8 5.2 5.6 6.0 6.4 6.8 7.2 7.6 R e sona nce width (Γ ) ...

Europhysics Letters (EPL), 2002

... and the close-coupling model Arindam Basu and AS Ghosh( ∗ ) Department of Theoretical Physics... more ... and the close-coupling model Arindam Basu and AS Ghosh( ∗ ) Department of Theoretical Physics, Indian Association for the Cultivation of Science Jadavpur, Kolkata 700 032, India ... Page 3. ArindamBasu et al.: Feshbach resonances in electron-positronium etc. 47 ...

EPL (Europhysics Letters), 2009

... 2s2 1Se resonance of H− in a Debye plasma Arindam Basu(a) Department of Physics, Maheshtala C... more ... 2s2 1Se resonance of H− in a Debye plasma Arindam Basu(a) Department of Physics, Maheshtala College - Budge Budge Trunk Road, Kolkata – 700 141, West Bengal, India ... Arindam Basu studied the collisional dynamics of electron scattering off hydrogenic ions in plasmas. ...

The European Physical Journal D, 2011

The lowest-lying 1, 3 P o and 1 D e resonances of positronium negative ion, Ps − , in weakly coup... more The lowest-lying 1, 3 P o and 1 D e resonances of positronium negative ion, Ps − , in weakly coupled plasmas have been investigated employing the close-coupling approximation. Three different basis sets have been employed in the present study. The plasma screening condition obtained from the Debye-Hückel type potential is used to represent the interaction between the charged particles. The resonance energies and the corresponding widths of one 1 P o , two 3 P o , and one 1 D e resonant states associated with the n = 2 threshold of the positronium atom for various Debye lengths ranging from infinity to small values are reported. The 1 P o resonance as well as the higher lying 3 P o resonant state transforms to a shape resonance for denser plasma conditions. The 1 D e resonant state also changes to a shape-type resonance for very dense plasmas.

The European Physical Journal D, 2011

Electron-hydrogen scattering has been investigated in Debye plasma environment employing the clos... more Electron-hydrogen scattering has been investigated in Debye plasma environment employing the close-coupling approximation. Two models, viz., 6-state CCA and 9-state CCA have been used. Plasma screening has been taken into account via Debye-Hückel model potential. The lowest lying 1 D e autodetaching resonance of the hydrogen negative ion has been successfully predicted for various plasma conditions. The resonant state changes to shape resonance for Debye scattering lengths less than a critical value.

Electron-positronium scattering and doubly excited autodetaching states of the positronium negati... more Electron-positronium scattering and doubly excited autodetaching states of the positronium negative ion AS GHOSH and ARINDAM BASU Department of Theoretical Physics, Indian Association for the Cultivation of Science, 2A&B Raja SC Mullick Road, Jadavpur, Kolkata-700 032, ...

Physical Review A, 2005

ABSTRACT

Physical Review A, 2001

Scattering of a Ps atom off a He target has been investigated in the framework of the close-coupl... more Scattering of a Ps atom off a He target has been investigated in the framework of the close-coupling approximation using two basis sets: (a) Ps(1s)+He(1s 2 ,1s2 1 s,1s2 1 p) and (b) Ps(1s,2p)+He (1s 2 ,1s2 1 s,1s2 1 p). Target inelastic channels reduce the elastic cross sections ...

Physical Review A, 2000

Projectile elastic close-coupling method is employed to investigate the positronium-hydrogen scat... more Projectile elastic close-coupling method is employed to investigate the positronium-hydrogen scattering using different basis sets to find the rate of convergence with added eigenstates and pseudostates. We report s-, p-, and d-wave phase shifts below the first positronium ...

Physical Review A, 2001

Scattering of orthopositronium off helium target has been investigated using close-coupling metho... more Scattering of orthopositronium off helium target has been investigated using close-coupling method in the energy range 0–110 eV. Two basis sets, (a) Ps(1s)+He(1s 2 , 1s2 1 s, 1s2 1 p) and (b) Ps(1s,2p)+He(1s 2 , 1s2 1 s, 1s2 1 p), have been employed to find the scattering ...

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2008

The effect of external environments such as that of plasma on atomic systems are currently intere... more The effect of external environments such as that of plasma on atomic systems are currently interesting topics of research [1], [2] and [3]. Some theoretical studies have been performed to estimate the ground states [1] and [2] and resonant states [3] and [4] of two electron atoms in Debye ...

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2004

Ortho-positronium–ortho-positronium (o-Ps–o-Ps) scattering is investigated using close coupling m... more Ortho-positronium–ortho-positronium (o-Ps–o-Ps) scattering is investigated using close coupling model. The following four basis sets have been employed: (1) Ps(1s) + Ps(1s) (2) Ps(1s,2s,2p ) + Ps(1s,2s,2p) (3) Ps(1s,2s,2 ) + Ps(1s,2s,2 ) and (4) Ps(1s,2s,2 , 3 ) + Ps(1s,2s,2 , 3 ) ...

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2004

Collisions involving atoms and antiatoms have been investigated at low incident energies using cl... more Collisions involving atoms and antiatoms have been investigated at low incident energies using close-coupling approximation (CCA). We investigate ortho-positronium-ortho-positronium (o-Ps-o-Ps) scattering up to incident energy 3.4 eV. Antihydrogen-hydrogen elastic scattering has been studied in the energy range 10 À10 to 10 À2 a.u., whereas antihydrogen-helium system has been investigated in the range 10 À16 to 10 À2 a.u. The s-wave elastic scattering parameters, viz., scattering length, effective range, phase shift, cross section etc., have been reported. The present predictions have been compared with the other corresponding theoretical predictions wherever available. Usefulness of CCA model to investigate these systems at thermal energies has been emphasized.

Journal of Physics B: Atomic, Molecular and Optical Physics, 2004

Page 1. Positronium–alkali atom scattering at medium energies This article has been downloaded fr... more Page 1. Positronium–alkali atom scattering at medium energies This article has been downloaded from IOPscience. Please scroll down to see the full text article. 2004 J. Phys. B: At. Mol. Opt. Phys. 37 1709 (http://iopscience.iop.org/0953-4075/37/8/012) ...

Journal of Physics B: Atomic, Molecular and Optical Physics, 2010

... Opt. Phys. 43 (2010) 115202 A Basu Table 1. The resonance positions and widths for the lowest... more ... Opt. Phys. 43 (2010) 115202 A Basu Table 1. The resonance positions and widths for the lowest lying 1,3Po auto-detaching resonances of H − under various plasma conditions. ... (E r) D in au 30 40 50 60 70 80 90 100 4.0 4.4 4.8 5.2 5.6 6.0 6.4 6.8 7.2 7.6 R e sona nce width (Γ ) ...

Europhysics Letters (EPL), 2002

... and the close-coupling model Arindam Basu and AS Ghosh( ∗ ) Department of Theoretical Physics... more ... and the close-coupling model Arindam Basu and AS Ghosh( ∗ ) Department of Theoretical Physics, Indian Association for the Cultivation of Science Jadavpur, Kolkata 700 032, India ... Page 3. ArindamBasu et al.: Feshbach resonances in electron-positronium etc. 47 ...

EPL (Europhysics Letters), 2009

... 2s2 1Se resonance of H− in a Debye plasma Arindam Basu(a) Department of Physics, Maheshtala C... more ... 2s2 1Se resonance of H− in a Debye plasma Arindam Basu(a) Department of Physics, Maheshtala College - Budge Budge Trunk Road, Kolkata – 700 141, West Bengal, India ... Arindam Basu studied the collisional dynamics of electron scattering off hydrogenic ions in plasmas. ...

The European Physical Journal D, 2011

The lowest-lying 1, 3 P o and 1 D e resonances of positronium negative ion, Ps − , in weakly coup... more The lowest-lying 1, 3 P o and 1 D e resonances of positronium negative ion, Ps − , in weakly coupled plasmas have been investigated employing the close-coupling approximation. Three different basis sets have been employed in the present study. The plasma screening condition obtained from the Debye-Hückel type potential is used to represent the interaction between the charged particles. The resonance energies and the corresponding widths of one 1 P o , two 3 P o , and one 1 D e resonant states associated with the n = 2 threshold of the positronium atom for various Debye lengths ranging from infinity to small values are reported. The 1 P o resonance as well as the higher lying 3 P o resonant state transforms to a shape resonance for denser plasma conditions. The 1 D e resonant state also changes to a shape-type resonance for very dense plasmas.

The European Physical Journal D, 2011

Electron-hydrogen scattering has been investigated in Debye plasma environment employing the clos... more Electron-hydrogen scattering has been investigated in Debye plasma environment employing the close-coupling approximation. Two models, viz., 6-state CCA and 9-state CCA have been used. Plasma screening has been taken into account via Debye-Hückel model potential. The lowest lying 1 D e autodetaching resonance of the hydrogen negative ion has been successfully predicted for various plasma conditions. The resonant state changes to shape resonance for Debye scattering lengths less than a critical value.