ATLAS E&O 18.06.2013, CERN

Report

International Masterclasses Uta Bilow, TU Dresden

www.physicsmasterclasses.org

International Masterclasses 2013

• 25.2. – 22.3.2013 (22 days)

• 161 MCs (Fermilab-based: 29) – ATLAS W: 55 – ATLAS Z: 58 (12)– CMS: 38 (17)– ALICE: 10

• 37 VCs with CERN (12)

• 130 institutes registered (29)

+ local Masterclasses, teachers´ days

~ 10 % growth for 2013

Further growth extended period

Running in 37 countries!New countries:

Romania Turkey

Cyprus Palestine

Egypt Australia

Video ConferencesCERN-based:• Test period 4.2. – 15.2. (Vidyo support

team)• 86 institutes tested (14 new institutes)• WG VC preparing:

– Manuals for VC for local organisers– Manual and twiki for moderators – Training for mod. at CERN 18.2.– Rooms (teachers´ lab, CMS centre)

• 33 Moderators! Rewarded with a Polar from the CERN shop

Vidyo worked well Institutes are clearly better trained in

2013 Still lacking: chat, visual indication of

speaker

Fermilab-based:• Crew of 3-4:

- Facilitator- Moderator (FNAL/ANL)- Tech- (Featured scientist)

• Icebreaker questions• No quiz

Improvements– 2011 real data: 693 WW/Higgs

candidates (from released 1fb-1) mixed with 900 W and 4047 background events, password protected, split up into subsamples

– Histogram tool developed• significance of data excess can be

calculated with any cut on (ll)– spreadsheet and histogram

websites connected with database

New ATLAS W-path with real WW (+H) events

MINERVA event display

Measurement– Wl– W+/W- ratio– WWll – Angular distribution

between leptons

http://atlas.physicsmasterclasses.org/en/wpath.htm

New ATLAS W-path

6

W+/W- ratio: 1.25

WW pairs recognition: quota too low, affects W+/W- ratio!

master thesis in physics didactics running

no new preselection necessary

revise cuts in decision tree for students

New ATLAS ZpathMaster the invariant mass technique

– categorise events: l+l-, mumu, 4l

– to study and measure the Z boson and other resonances (J/) decaying to l+l-

– to search for new physics (Z’)

– to search for the Higgs boson in and l+l-l+l-

Data from 2011– 10.000 l+l- events (password protected, 100 free)

– 1.000 fully simulated Z’ events

– 13 data groups/directories, 20 subgroups (A-T), and 50 events/mixed sample/2 students

– 50% Z, 30% 10% (J/, 5% Z', 5% l+l-l+l-

– Higgs candidate events:

– 1 fb-1 and cuts according to ATLAS publication

– corresponding Higgs MC signals (125 GeV )

M()=125 GeV

M(ee)=123 GeV

HYPATIA event display

http://atlas.physicsmasterclasses.org/en/zpath.htm

New ATLAS Zpath

OPloT: – Mll and/or M and/or Mllll

– discussed locally and in VC– Invariant mass as a tool to

identify particles, to discover new particles, and to search for exotic particles

Measurements• J/ for schools, workshops• W/Z for IMCEvent display• iSpy-online with capabilities to

zoom, rotate, switch objects on/offImprovements• Better transfer of results• Now in 11 languages• Add a small number of Higgs

candidates (4 leptons only)

CMS measurements

9

Measurement• Option 1

– Strangeness: decay patterns of V0s: K0s, Λ, anti-Λ from p-p collisions

• Option 2– Measure nuclear suppression factor RAA

New and noteworthy• visual analysis:

– 30 events (2012) , 15 events (2013)

• Samples– Small p-p at 7 TeV – large pb-pb at 2.76 TeV

• p-Pb collisions in 2012 – show different result from Pb-Pb samples:

evidence of hot plasma?

ALICE measurements

10

Organisation, Funding, Support• Central organisation at TU Dresden

Michael Kobel, Uta Bilow (financed by CERN until 2015), student assistants

• Coordination Fermilab-based MCs (America, Far East, Australia) Ken Cecire (supported by QuarkNet)

• WG Video conference (Kate Shaw, Michael Hauschild, Laurenz Widhalm†, Uta Bilow)

• Steering group (Farid Ould-Saada, Michael Kobel, Ken Cecire, Pete Watkins, Despina Hatzifotiadou, Yiota Foka, Ralf Averbeck, Uta Bilow)

• Funding from EPS HEPP Division• in kind contributions (CERN, Fermilab, Vidyo team, moderators, …)

IMC steering group and the IPPOG co-chairs working to establish a document: mandate of group, membership, quality assurance, procedure for new measurements,

Currently, measurements from ALICE, ATLAS, CMSLHCb measurement (Lifetime of D0) expected in 2014 – not yet approved by IMC SGTOTEM preparing measurementAMS expressed interest in participation

Summary Measurements and tools improved, better

combination, no last-minute aid

Very positive feedback, esp. from newcomers

„smooth as silk“, „great“, „excellent“

„very nice opportunity to share our science with young students and it also produces some common goals for our team of researchers“

Most feedback on VC: too long / too short, earlier / later