SeSAM Documentation

Content:

1.      Registration

2.      Go to our page

3.      Choose a default model

4.      Modify parameters and run

5.      Check results and download

6.      More details

Back to SeSAM main

 
 

 

 

 

 

 

 

 

 

 


Here we provide some details on how to run models with our public tool.

This application was designed and built by Gerard Lemson and Laurent Bourges.

 

1.   Registration

You need to register in order to run models on our server. Please send an email to Gerard Lemson

(“gerard.lemson” at domain “mpe.mpg.de”). You only need to ask for “sesam permission”

and specify your full name and institute. 

 

2.   Go to our page

 

Follow this link to GAVO, and press “Go” as shown below:

 

 

 

3. Choose a default model

 

Choose one of our default models using the scroll-down list button and press “Choose”.

The parameters within this page are updated only when “Choose” is pressed.

 

 

 

 

4.   Modify parameters and run

 

You can now modify all the parameters within this page, for more details see section #6.

When you are ready, press “Submit” as shown below. Your model is now being run on GAVO

servers.

 

 

 

 

5.   Check results and download catalogs

 

Wait ~30 seconds, “reload” the web-page and click “result.zip” to download galaxy catalogs.

 

The “Detail” page contains results of your run; use the “reload” button in order to update this page.

Each model takes ~20 seconds to run, and a few more seconds to write the output data. It may take

more when the server is busy, in this case your job will be added to a job queue. You can check the

queue by clicking “Job Queue”. Once the run is done and “reload” was pressed, the page will look

like the example below. It provides a few plots which compare your model to the observational data.

Click “result.zip” in order to download full catalogs of galaxies. For more details on this page see section #6.

 

Files to

download

 

The status of

 your run

 

 

 

 

6.   More details

 

6.1  How to modify parameters

                       

-         Each line includes a set of parameters that are used to fix one quantity (e.g. “f_s”).

-         The quantity name is the same as is used in the paper.

-         A full description of each parameter appears at the same line. For example,

the picture below shows the part which is used to fix the behavior of the SF efficiency.

The first number on the left corresponds to f_s[0], the second to f_s[1], etc.

-         In some cases (f_s, f_d, f_c) the user can specify a file name. These files are the ones

used by our default models, and their values are given in the appendix of the paper.

Choose “-1” is you do not want to use a file; in this case the value of f_s will be fixed

by the parameters f_s[0] – f_s[3]. On the other hand, choosing a file name will force the

model to use numerical values from the file, and ignore the parameters f_s[0] – f_s[3].

 

 

-         In the future we will allow users to upload their own parameter files.

-         Make sure that the parameter values you use are reasonable. We do not check these values

before running your model.

-         All the parameters used by the model are saved to the file: “esam_params”. This file is included

within the archive “results.zip”, but you can download it separately.

 

 

          6.2  How to interpret the results

 

-         The results of the public runs are based on merger-trees from the Milli-Millennium simulation.

This simulation is based on a 62.5 Mpc/h box size, a volume that is 512 times smaller than

the full Millennium simulation used in the paper. For this reason there might be differences between

results obtained here and the results shown in the paper.

-         We provide a few plots to compare the model results to observations. These plots are done in the

same way as was done in the paper. For more details on these plots, please refer to the paper. In all

plots the model results are shown in red.

-         In order to fully evaluate your model, we recommend downloading the galaxy catalogs. The *.zip file,

“result.zip”, includes all galaxies at the following redshifts:

0 0.2 0.4 0.6 0.8 1.0 1.2 1.5 2.0 2.5 3.0 3.5 4.0 5.0

 

 

 

          6.3  Errors

 

                         The most common error is obtained when the efficiencies values are too high.

                         In this case the error message will look like the example below. You would need

 to check yourself that the values of each efficiency (i.e. f_s, f_c, f_d, f_e, f_r)

                         do not exceed the limit of ~100. Such high efficiencies mean that drastic changes

                         in the mass component of a galaxy will occur on time scales of ~10 Myr, which is not

                         allowed by this public tool.

 

 

 

 

6.4     Manage your runs

 

-         Each user can add no more than 6 jobs to the queue system.

-         You can view all your previous runs using the “history” link.

We will try to keep the full data from each run for at least one day,

      after this time only the parameter file, “esam_params”, will be saved.

 

 

6.5     Tell us what you think!

 

This is the first application done by GAVO “Jobrunner” so we need your feedback!

Please let us know if you have any comments, questions or problems.

 

 

Goto: top of this page,  SeSAM main

 

This page was last modified on February 10, 2009