Mass methods
From Wiki Les Houches 09
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- | | | + | | Mass differences in leptonic decays. |
- | | | + | | Dependence on mass scale is weak. |
| Intermediate 3-body decays? Combinatoric (other side) jets not considered. Calorimeter nonlinearity? | | Intermediate 3-body decays? Combinatoric (other side) jets not considered. Calorimeter nonlinearity? | ||
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Revision as of 08:14, 23 June 2009
Variable/Method | Reference(s)/Code | Realm of Applicability | Precision | Good for | Fails for | Unknown/Future directions |
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MT | (ancient) | one missing particle | ||||
Meff | always | does not identify process in any way | ||||
HT | always | does not identify process in any way | ||||
Edges | (lots) | Mass differences in leptonic decays. | Dependence on mass scale is weak. | Intermediate 3-body decays? Combinatoric (other side) jets not considered. Calorimeter nonlinearity? | ||
MT2 | hep-ph/9906349 | |||||
MT2 kink ("stransverse" mass) | arXiv:0709.0288 | 4-body final state, 2 missing | large mass differences and large pT | small mass differences or no pT | ||
MTn | 4-body final state, n missing | |||||
MTgen | arXiv:0708.1028 | |||||
M2C | arXiv:0712.0943 | |||||
M3C | arXiv:0811.2138 | |||||
arXiv:0812.1042 | ||||||
Exactly-constrained Polynomials | arXiv:0707.0030 | 4 on-shell intermediate resonances, 2 missing | Apply to squark-neutralino2-slepton-neutralino1 cascade where other side is squark-neutralino1. | |||
Multi-event Polynomial intersection | arXiv:0802.4290 | 5 or more on-shell intermediate resonances, 2 missing | Statistics of histograms created with n-event subsets; If mass differences are fixed and the masses are increased, what happens? (Sabine Kraml); Develop methods for asymmetric chains and < 6 intermediate resonances. |
- How can we define "Precision" in a manner that lets us meaningfully compare different methods? A lot of process-specific assumptions and backgrounds usually enter the application of each method.
- In general, all methods need to be systematically tested in cases where the assumptions needed for the method are not satisfied.
- Appropriate consideration of ISR/FSR jets is not usually considered. Requires 2->3 matrix elements where the hard scattering process includes a possible extra hard quark/gluon radiation.