Recent changes to Home

Home modified by Jakub Benda

Jakub Benda — Thu, 12 Jun 2014 07:54:14 -0000

--- v4
+++ v5
@@ -19,16 +19,13 @@
 Hex-dwba
 --------

-This is the intermediate-to-high-energy program. The T-matrices are sought using the distorted wave Born approximation of the first order. To evaluate perturbation contributions, a lot of integration is necessary. That is implemented using the Clenshaw-Curtis algorithm assisted by discrete cosine transform computed by the power of [FFTW](http://www.fftw.org/).
+This is the high-energy program. The T-matrices are sought using the distorted wave Born approximation of the first order. To evaluate perturbation contributions, a lot of integration is necessary. That is implemented using the Clenshaw-Curtis algorithm assisted by discrete cosine transform computed by [FFTW](http://www.fftw.org/).

-Hex-pwba
---------
-
-High-energy region (> 100 keV) can be satisfactorily described by the primitive first-order plane wave Born approximation, which, if the exchange is disregarded, is nothing more than a Fourier transform of the potential. 
+High-energy region (> 100 keV) can be satisfactorily described by the primitive first-order plane wave Born approximation, which, if the exchange is disregarded, is nothing more than a Fourier transform of the potential.

 Hex-db
 ------

-The fourth pillar **Hex-db** is a name of the database interface. All above mentioned programs output partial T-matrices that can be easily stored in a common [SQLite](http://www.sqlite.org/) database. **Hex-db** then serves as an easy and script-friendly way of retrieving these numbers. In addition to that, several common derived scattering quantities (like cross sections and collision strengths) are implemented in the code and can be computed on request from the basic data.
+The last pillar **Hex-db** is a name of the database interface. All above mentioned programs output partial T-matrices that can be easily stored in a common [SQLite](http://www.sqlite.org/) database. **Hex-db** then serves as an easy and script-friendly way of retrieving these numbers. In addition to that, several common derived scattering quantities (like cross sections and collision strengths) are implemented in the code and can be computed on request from the basic data.

 **Hex-db** also has a simple HTML form interface for deployment on servers. An example, and official presentation of the results, is on the [UTF web page](http://utf.mff.cuni.cz/~benda).

Home modified by Jakub Benda

Jakub Benda — Thu, 30 Jan 2014 17:21:51 -0000

--- v3
+++ v4
@@ -3,23 +3,23 @@

 (Hydrogen-electron collisions code)

-Jakub Benda, MFF UK (c) 2013
+Jakub Benda, MFF UK (c) 2014

 -------------------------------------------

 Hex is a package of several programs used for computation of T-matrices and derived scattering quantities of a collision of electron with atomic hydrogen. The method used is the non-relativistic quantum mechanics with different approximations depending on the energy of the projectile.

-Hex-main
+Hex-ecs
 --------

-**Hex-main** is the most complex and computationally demanding package of the four. It is used for solving the scattering problem in the low-energy regime, which means situations when the projectile energy is not considerably larger than the ionization threshold of the atom. With thinkable resources, the program can produce valid results for energies up to, say, 100 eV but certainly not higher. Moreover, this optimistic number holds just for scattering on the ground state. Excited states require *much, much* larger temporal and memory requirements.
+**Hex-ecs** is the most complex and computationally demanding package of the four. It is used for solving the scattering problem in the low-energy regime, which means situations when the projectile energy is not considerably larger than the ionization threshold of the atom. With thinkable resources, the program can produce valid results for energies up to, say, 100 eV but certainly not higher. Moreover, this optimistic number holds just for scattering on the ground state. Excited states require *much, much* larger temporal and memory requirements.

 The implemented method is the discretization of the Schrödinger equation in a [B-spline](http://en.wikipedia.org/wiki/B-spline) basis. The whole equation is solved for every global angular symmetry as a set of linear algebraic equations, i.e. using a LU-decomposition. [Umfpack](http://www.cise.ufl.edu/research/sparse/umfpack/) library was chosen for this task. The results are the partial T-matrices for every outgoing particle partial wave.

 Hex-dwba
 --------

-This is the intermediate-to-high-energy program. The T-matrices are sought using the distorted wave Born approximation, either of the first or second order. To evaluate perturbation contributions, a lot of integration is necessary. That is implemented using the Clenshaw-Curtis algorithm assisted by discrete cosine transform computed by the power of [FFTW](http://www.fftw.org/).
+This is the intermediate-to-high-energy program. The T-matrices are sought using the distorted wave Born approximation of the first order. To evaluate perturbation contributions, a lot of integration is necessary. That is implemented using the Clenshaw-Curtis algorithm assisted by discrete cosine transform computed by the power of [FFTW](http://www.fftw.org/).

 Hex-pwba
 --------
@@ -29,6 +29,6 @@
 Hex-db
 ------

-The fourth pillar **Hex-db** is a name of the database interface. All above mentione programs output partial T-matrices that can be easily stored in a common [SQLite](http://www.sqlite.org/) database. **Hex-db** then serves as an easy and script-friendly way of retrieving these numbers. In addition to that, several common derived scattering quantities (like cross sections and collision strengths) are implemented in the code and can be computed on request from the basic data.
+The fourth pillar **Hex-db** is a name of the database interface. All above mentioned programs output partial T-matrices that can be easily stored in a common [SQLite](http://www.sqlite.org/) database. **Hex-db** then serves as an easy and script-friendly way of retrieving these numbers. In addition to that, several common derived scattering quantities (like cross sections and collision strengths) are implemented in the code and can be computed on request from the basic data.

 **Hex-db** also has a simple HTML form interface for deployment on servers. An example, and official presentation of the results, is on the [UTF web page](http://utf.mff.cuni.cz/~benda).

WikiPage Home modified by Jakub Benda

Jakub Benda — Mon, 25 Feb 2013 16:58:56 -0000

--- v2
+++ v3
@@ -31,4 +31,4 @@

 The fourth pillar **Hex-db** is a name of the database interface. All above mentione programs output partial T-matrices that can be easily stored in a common [SQLite](http://www.sqlite.org/) database. **Hex-db** then serves as an easy and script-friendly way of retrieving these numbers. In addition to that, several common derived scattering quantities (like cross sections and collision strengths) are implemented in the code and can be computed on request from the basic data.

-**Hex-db** also has a simple HTML form interface for deployment on servers.
+**Hex-db** also has a simple HTML form interface for deployment on servers. An example, and official presentation of the results, is on the [UTF web page](http://utf.mff.cuni.cz/~benda).

WikiPage Home modified by Jakub Benda

Jakub Benda — Mon, 11 Feb 2013 18:05:28 -0000

--- v1
+++ v2
@@ -1,8 +1,34 @@
-Welcome to your wiki!
+Hex
+===========================================

-This is the default page, edit it as you see fit. To add a new page simply reference it within brackets, e.g.: [SamplePage].
+(Hydrogen-electron collisions code)

-The wiki uses [Markdown](/p/hecs/wiki/markdown_syntax/) syntax.
+Jakub Benda, MFF UK (c) 2013

-[[project_admins]]
-[[download_button]]
+-------------------------------------------
+
+Hex is a package of several programs used for computation of T-matrices and derived scattering quantities of a collision of electron with atomic hydrogen. The method used is the non-relativistic quantum mechanics with different approximations depending on the energy of the projectile.
+
+Hex-main
+--------
+
+**Hex-main** is the most complex and computationally demanding package of the four. It is used for solving the scattering problem in the low-energy regime, which means situations when the projectile energy is not considerably larger than the ionization threshold of the atom. With thinkable resources, the program can produce valid results for energies up to, say, 100 eV but certainly not higher. Moreover, this optimistic number holds just for scattering on the ground state. Excited states require *much, much* larger temporal and memory requirements.
+
+The implemented method is the discretization of the Schrödinger equation in a [B-spline](http://en.wikipedia.org/wiki/B-spline) basis. The whole equation is solved for every global angular symmetry as a set of linear algebraic equations, i.e. using a LU-decomposition. [Umfpack](http://www.cise.ufl.edu/research/sparse/umfpack/) library was chosen for this task. The results are the partial T-matrices for every outgoing particle partial wave.
+
+Hex-dwba
+--------
+
+This is the intermediate-to-high-energy program. The T-matrices are sought using the distorted wave Born approximation, either of the first or second order. To evaluate perturbation contributions, a lot of integration is necessary. That is implemented using the Clenshaw-Curtis algorithm assisted by discrete cosine transform computed by the power of [FFTW](http://www.fftw.org/).
+
+Hex-pwba
+--------
+
+High-energy region (> 100 keV) can be satisfactorily described by the primitive first-order plane wave Born approximation, which, if the exchange is disregarded, is nothing more than a Fourier transform of the potential. 
+
+Hex-db
+------
+
+The fourth pillar **Hex-db** is a name of the database interface. All above mentione programs output partial T-matrices that can be easily stored in a common [SQLite](http://www.sqlite.org/) database. **Hex-db** then serves as an easy and script-friendly way of retrieving these numbers. In addition to that, several common derived scattering quantities (like cross sections and collision strengths) are implemented in the code and can be computed on request from the basic data.
+
+**Hex-db** also has a simple HTML form interface for deployment on servers.

Discussion for Home page

Jakub Benda — Mon, 11 Feb 2013 18:04:41 -0000

Hex

(Hydrogen-electron collisions code)

Hex is a package of several programs used for computation of T-matrices and derived scattering quantities of a collision of electron with atomic hydrogen. The method used is the non-relativistic quantum mechanics with different approximations depending on the energy of the projectile.

Hex-main

Hex-main is the most complex and computationally demanding package of the four. It is used for solving the scattering problem in the low-energy regime, which means situations when the projectile energy is not considerably larger than the ionization threshold of the atom. With thinkable resources, the program can produce valid results for energies up to, say, 100 eV but certainly not higher. Moreover, this optimistic number holds just for scattering on the ground state. Excited states require much, much larger temporal and memory requirements.

The implemented method is the discretization of the Schrödinger equation in a B-spline basis. The whole equation is solved for every global angular symmetry as a set of linear algebraic equations, i.e. using a LU-decomposition. Umfpack library was chosen for this task. The results are the partial T-matrices for every outgoing particle partial wave.

Hex-dwba

This is the intermediate-to-high-energy program. The T-matrices are sought using the distorted wave Born approximation, either of the first or second order. To evaluate perturbation contributions, a lot of integration is necessary. That is implemented using the Clenshaw-Curtis algorithm assisted by discrete cosine transform computed by the power of FFTW.

Hex-pwba

High-energy region (> 100 keV) can be satisfactorily described by the primitive first-order plane wave Born approximation, which, if the exchange is disregarded, is nothing more than a Fourier transform of the potential.

Hex-db

The fourth pillar Hex-db is a name of the database interface. All above mentione programs output partial T-matrices that can be easily stored in a common SQLite database. Hex-db then serves as an easy and script-friendly way of retrieving these numbers. In addition to that, several common derived scattering quantities (like cross sections and collision strengths) are implemented in the code and can be computed on request from the basic data.

Hex-db also has a simple HTML form interface for deployment on servers.

WikiPage Home modified by Jakub Benda

Jakub Benda — Sun, 13 Jan 2013 19:18:54 -0000

Welcome to your wiki!

This is the default page, edit it as you see fit. To add a new page simply reference it within brackets, e.g.: [SamplePage].

The wiki uses Markdown syntax.

Jakub Benda