Higgs to di-photon workshop hosted by ATLAS

CERN has recently hosted an HGamma workshop at the Business Center in St-Genis. This 2.5 day workshop (from Monday April 27th to Wednesday April 29th) was intended to assess the readiness of HGamma analyses for run2. HGamma is the name given to this particular decay channel being studied. A walkthrough for early analyses was given followed by a review of the status of combined performance and common tools. This was followed by a look at all longer term analyses which require more data.

The Wits members involved in the HGamma group include:

1. Luis March 
2. Mthokozisi Masuku 
3. Bruce Mellado 
4. Stefan von Buddenbrock 
5. Deepak Kar 
6. Oscar Kureba 
7. Shell-May Liao 
8. Robert Graham Reed 
9. Xifeng Ruan 
10. Kehinde Gbenga Tomiwa

The University of the Witwatersrand had a total of five presentations. The presenters and topic overviews were:

• Luis March - This talk discussed the new Missing Transverse Momentum (ETmiss) definition that will combat the issues associated with the increase in collision energy. The presentation showed the status and development of the ETmiss for Run-II, comparing the performance of two ET miss definitions by using Monte Carlo datasets. In addition, the status of an ETmiss tool which will be used by the missing energy groups was shown.

• Robert Reed - An overview talk about the status of the analysis framework for the Higgs to di-photon and di-bjet decay channel. This is a sub analysis of the HGamma channel. The talk included a short tutorial on how to run the analysis and the selection criteria involved. Further studies were presented regarding jet energy resolutions as well as simulation type comparisons.

• Xifeng Ruan - Presented three talks:

1. This talk presented the inauguration of a new study involving the Higgs and missing transverse energy (ETmiss). This is a primary candidate in the study for beyond the Standard Model. The talk involved the understanding of the missing transverse energy from the 2011, 2012 and 2015 data to look for new physics. 
2. A summary of the recent simulation samples was shown. The simulation samples are the theoretical estimates we should observe during data taking. The ETmiss group has requested new samples for study for the new data period in 2015. 
3. A detailed look at the future prospects of the ETmiss study was discussed. This included the intermediate and high ETmiss/BSM groups. This also included all the ongoing efforts in the group.