This page aims to give an overview of the necessary steps and links to get started relatively quickly in the UZH's CMS group.
If you are a Bachelor's or Master's student, you can best get an external CERN account, a CMS account and an account at PSI's Tier3.
If you already have a CERN account, you can change your status and home institute as described here.
It is possible to register as an external CERN collaborator if you only require a computing account (lxplus
) and other electronic services. With such an external CERN account you do not need to go to CERN, but you do need a CMS registration.
You will receive a reply outlining the next steps for CMS registration which are also described in the section about CMS below.
Follow these steps of CERN's User Office to register as a full CERN member. You will need to
After this, you will receive a confirmation e-mail with an attestation of pre-registration. To complete the registration, go to the CERN Users' Office in Geneva. You will need to bring your identity card or passport, Home Institution Declaration, attestation of pre-registration and if you are staying in Switzerland a visa or residence permit (Ausländerausweis / Livret pour étrangers).
When this is completed you will get more instructions (cyber-security exam, emergency contacts form, …), but most of all a CERN e-mail address and a CERN computing account at the CERN lxplus cluster!
More information on
You can request CMS registration by filling in this form. (For the “Main project at CMS” field, choose “Tracker”.) Upon submission, you will receive an e-mail with a link to upload a scan of an identity card or passport, and a link to a registration form. After submitting all of that, ask the team leader of our CMS group (Florencia at the moment of writing) to confirm your CMS registration. Then you will get information on how to activate your account.
After all that, you should register with VOMS, get and install GRID certificates on your local computer and computing accounts. These certificates give you authorized acces to a number of grid computing services. Follow the steps lined out here and here. In summary:
cert.p12
.scp
for example). From these .p12
files, create .pem
files to install them.
To create the .pem
files from the .p12
certicicate, and set the correct permissions:
# if needed: copy the cert.p12 file to lxplus/t3ui03/... using scp mkdir $HOME/.globus openssl pkcs12 -in cert.p12 -clcerts -nokeys -out $HOME/.globus/usercert.pem openssl pkcs12 -in cert.p12 -nocerts -out $HOME/.globus/userkey.pem chmod go-rw $HOME/.globus/userkey.pem # set read permissions
Test with
voms-proxy-init -voms cms
This will also create a file like /tmp/x509up.u<user-id>
, where <user-id>
is your user ID, found with the id -u
command. You can specify the proxy's location by including the following in your .bashrc
:
export X509_USER_PROXY=~/.x509up_u`id -u`
Our UZH group uses PSI's servers for computing (since it has more storage space than CERN's lxplus). To get a computing account at Tier3, you first need a CERN lxplus account. Please follow these steps to get an PSI T3 account. You will need to send a formatted e-mail, for example:
User's first name: John User's last name: Doe Institute/group: Physik-Institute/Kilminster Institution: UniZ group leader: Ben Kilminster CMS hypernews name: jdoe physics group: uniz-higgs Grid cert subject: /DC=ch/DC=cern/OU=Organic Units/OU=Users/CN=jdoe/CN=137035/CN=john doe User's phone number: +41 7 13 70 35 99 PSI AFS account (if existing): login shell: /bin/bash mail: john.doe@uzh.ch secondary mail address: john137@hotmail.com leaving date: -1
uniz-higgs
.bash
(which is also standard on Mac OS. Z shell zsh
is more customizable and interactive and so a bit more complicated for beginners.)usercert.pem
) installed yet, and share it with the T3 admins later. Until then, you will not be able to make use of certain services such as acces to T3's storage element (/pnfs
). Otherwise, use one of the following commands on your lxplus
or local certificate file usercert.pem
:openssl x509 -subject -dates -noout -in ~/.globus/usercert.pem voms-proxy-info --subject
CMS Hypernews is used as a mailing list for CMS groups, a discussion forum for review (approval) of CMS papers and a inbox spamming device. You can create an account and password in the lxplus command line:
ssh hypernews.cern.ch
and voluntarily sign up for several forums (your favorite analyses, CMS groups, etc.)
Note: Hypernews will be archived and replaced by CMS Talk at the end of 2021, see this tutorial.
Indico is used by CERN for video conferences and meetings. Install Vidyo after singing up with your CERN account. Links to the UZH CMS Group meetings and other can be found here.
If you are a non-doctoral student you are likely not on the author list for CMS publications (yet). If you do not have access to CMS physics meetings on Indico with your CERN account, you might not be in the cms-physics-access
e-group. You can verify by going to your CERN account page,
to, “My Accounts”
to “Check account status...”, under “E-Group membership”. If you are not part of cms-physics-access
, ask you group leader to add you as an exception via http://cms.cern.ch/iCMS/admin/newexception.
For renewal, please get a signed Home Institute Declaration (from Regina at the moment of writing), and fill out the this EDH form.
After registering you need to know how to acces and setup your account.
As a student, you can make an account here, and more info here.
To connect remotely to UZH's physics linux cluster, CERN's lxplus or PSI T3 servers, use the secure shell command ssh
in a Terminal:
ssh <username>@linux.physik.uzh.ch ssh <username>@lxplus.cern.ch ssh <username>@t3ui03.psi.ch
Where <username>
is you username. On a Mac OS, you should use ssh -Y
and make sure that XQuartz is installed (this is a X Window System tool, formerly X11, allowing you to run remote linux applications with GUI's on your Mac OS).
At the time of writing, UZH members should use T3's User Interface server ui03
.
Protip: Connecting to the UZH or PSI T3 can be done passwordlessly (at your own risk). Follow these instruction. (CERN is more difficult; please let me know if you find a way.)
From your local computer, you can copy stuff to a remote account or vice versa with secure copy scp
, for example:
scp <username>@linux.physik.uzh.ch:~/somefile.txt ./ # UZH to local scp foo.txt <username>@linux.physik.uzh.ch:~/ # local to UZH scp <username>@ineuteli@t3ui03.psi.ch:~/foo.txt ./ # PSI to local scp foo.txt <username>@ineuteli@t3ui03.psi.ch:~/ # local to PSI
Where <username>
is your username. Use the recursive flag -r
to copy directories like you would with the standard copy command cp
. It will ask your password, unless you have setup a passwordless ssh
login.
Please read How to set up your account at PSI Tier-3 and make note of the PSI Tier-3 policies about disk quotas and more; at the moment:
/shome/$USER
: 400 GB (current data, including past data saved in snapshots /shome/$USER/.zfs/snapshot
)/scratch
: 4TBCheck your currently used and available space here.
To use CMS-related commands and root
at PSI T3, you will need to first run
source $VO_CMS_SW_DIR/cmsset_default.sh
at every login. The environmental variable VO_CMS_SW_DIR
should be /cvmfs/cms.cern.ch
.
If you want to use root
, you first need to get a CMSSW
release and run cmsenv
in its src
directory with every login. Check the next subsection.
Furthermore, to make use of certain services such as acces to T3's storage element (/pnfs
), you will need to initiate a VOMS proxy certificate every once in a while:
voms-proxy-init -voms cms -valid 200:0 # valid for 200 hours
To use root
on the UZH cluster, first run these two commands:
cd /cern/root_v5.34.25 source bin/thisroot.sh
Beginner's tip: In any shell you can have user defined commands with alias
and argument-taking functions using function
. For example:
alias sshp='ssh <username>@t3ui03.psi.ch' alias cdA='cd ~/analysis/' function cppl { scp -r <username>@t3ui03.psi.ch:~/"$1" ./; } # copy first argument from PSI to local
These command line definitions and the root
setup scripts above can be saved in the start-up file, which are located in your home directory ~/
and are run everytime you log into a new session. In a bash
shell these are .bashrc
and .bash_profile
, in the Z shell zsh
it is .zshrc
. Check whether they exist with ls -a ~/
and use Google for more information.
CMSSW
is a framework that is used for many different CMS related analyses. More information on the recommended version can be found here (existing releases are found with scram list -a
). To get for example CMSSW 8.0.20
on lxplus or T3, use:
cmsrel CMSSW_8_0_20 cd CMSSW_8_0_20/src cmsenv
After this you can run root
. Every time you start a new session, you will need to run
cd CMSSW_8_0_20/src cmsenv
When you use other packages, it can be installed in the CMSSW
's src
directory, after which you compile everything with scram
:
cd CMSSW_8_0_20/src scram b distclean scram b -j8
As a UZH member, you have acces to freely view article in large journals such as Physics Letters and APS from a UZH netwerk. When you are not connected to a UZH network, you can still get acces with a VPN proxy.
With CMS hypernews you can follow discussions on papers and much more.
Internal CMS documents can be found on iCMS under CMS Publications. Public articles such as Public Analysis Summaries (PAS) and much more can be found on the CERN Document Server (CDS).
On iCMS you can also request new Analysis Notes (AN).
This TWiki page summarizes the procedure to request a CMS note or paper. This TWiki pages summarizes how to use Apache Subversion's svn
(similar to git
) and the Technical Document Register's tdr
system. Guidelines for authors can be found here, here and here.
CERN members have access to professional accounts on the online LaTeX editor Overleaf, see here. With this editor, it is possible to edit LaTeX files simultaneously with other people. However, to compile CMS documents, a few steps are involved, see this or this TWiki page.
For approval, authors need to find a language editor themselves, see this TWiki page with CMS certified language editors
CMS analysis and physics symmary notes automatically complies with the CMS house style when using the LaTeX template of the tdr
system. For more info, see:
To make CMS plots, use the mentioned macros. You may have to update CMSStyle.py
for you needs and preferences. In python
for example, use it like this:
import CMSStyle CMSStyle.extraText = "Preliminary" CMSStyle.outOfFrame = True CMSStyle.lumi_13TeV = "" CMSStyle.setTDRStyle() CMSStyle.setCMSEra(2018) # or CMSStyle.setCMSEra(2018,lumi=59.7,cme=13,extra="Preliminary") # make TCanvas, TH1, ... CMSStyle.setCMSLumiStyle(canvas,0)
Once you have started your position as a PhD student or higher, check if you are on the CMS author list.
To be include its members to the author list, the group needs to have enough EPR points. Each member can perform some service works to gain EPR. You can pledge for EPRs for tasks here. You can sign up for shifts on CMS online.
Every six months a CMS induction course is organized for new members. Here are the slides of the one in January of 2020.
CERN provides several safety course, some of which are mandatory for beginners or for access to CMS. You can enroll on the Learning Hub. Other courses, including those for CMS underground guides, are provided.
Here is kept a list of CMS schools, (e.g. DAS School), and here is the CERN school.
Once you are here, make sure you receive a key and a validated student/staff card (legi) to acces the building and get discount at lunch. Also ask Roland to put you on the e-mail lists for our UZH CMS group.
Internal information:
Each time you travel, you can get reimbursed with one of these forms (“Dienstreise-Abrechnung”).
Traveling by public transport in Switzerland is cheaper with the half-fare pass (Halbtax). The half-fare pass can be reimbursed by the UZH, but only after your rail travel expenses have exceed double the cost of the half-fare pass. (This corresponds to about CHF 330–370, or at least four round trips between CERN and Zurich).
Some rules for meals:
Some rules for travel:
Each PhD student has teaching studies as outlined in the general regulations (linked above):
In the Student Admin tool (link above) you have to enter the number of hours you spend on teaching during you PhD. This is one of the milestones towards you graduation. Before you can book the date of your defense, your supervisor (i.e. Ben, Florencia, …) has to approve your numbers.
Protip: Try to keep your hours in the Student Admin Tool updated every 1–2 semesters, and same for the credit points.
To give a rough rule of thumb for calculating your hours to enter into the Student Admin tool:
Internal Information
> Corporate Design UZH
(may require log-in, or UZH network / VPN).ROOT
are linked to on this page.git
comes pre-installed in most command lines. This group has its own GitHub repository. Check this page out for more information./afs
./afs
or /eos
directory.