# Setting limits and making discoveries in CDF

## Abstract

This paper presents the statistical methods used in setting limits and discovery significances in the search for new particles in the CDF experiment at the Fermilab Tevatron. For single-channel counting experiments the collaboration employs the classical Helene formula, with Bayesian integration over systematic uncertainties in the signal acceptance and background. For more complex cases such as spectral fits and combining channels, likelihood-based methods are used. In the discoveries of the top quark and B{sub c} meson, the significance was estimated from the probability of the null hypothesis, using toy Monte Carlo methods. Lastly, in the recent SUSY/Higgs Workshop the Higgs Working Group used a method of combining channels and experiments based on the calculation of the joint likelihood for a particular experimental outcome, and averaging over all possible outcomes.

- Authors:

- Publication Date:

- Research Org.:
- Fermi National Accelerator Lab., Batavia, IL (US)

- Sponsoring Org.:
- USDOE Office of Energy Research (ER) (US)

- OSTI Identifier:
- 754856

- Report Number(s):
- FERMILAB-Conf-00/048-E

TRN: US0002392

- DOE Contract Number:
- AC02-76CH03000

- Resource Type:
- Conference

- Resource Relation:
- Conference: Workshop on Confidence Limits, Geneva (CH), 01/17/2000--01/18/2000; Other Information: PBD: 15 May 2000

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 43 PARTICLE ACCELERATORS; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; FERMILAB TEVATRON; PARTICLE IDENTIFICATION; STATISTICS; LIMITING VALUES; FERMILAB COLLIDER DETECTOR; SUPERSYMMETRY; HIGGS BOSONS; HIGH ENERGY PHYSICS; EXPERIMENT PLANNING

### Citation Formats

```
J. Conway.
```*Setting limits and making discoveries in CDF*. United States: N. p., 2000.
Web.

```
J. Conway.
```*Setting limits and making discoveries in CDF*. United States.

```
J. Conway. Mon .
"Setting limits and making discoveries in CDF". United States. https://www.osti.gov/servlets/purl/754856.
```

```
@article{osti_754856,
```

title = {Setting limits and making discoveries in CDF},

author = {J. Conway},

abstractNote = {This paper presents the statistical methods used in setting limits and discovery significances in the search for new particles in the CDF experiment at the Fermilab Tevatron. For single-channel counting experiments the collaboration employs the classical Helene formula, with Bayesian integration over systematic uncertainties in the signal acceptance and background. For more complex cases such as spectral fits and combining channels, likelihood-based methods are used. In the discoveries of the top quark and B{sub c} meson, the significance was estimated from the probability of the null hypothesis, using toy Monte Carlo methods. Lastly, in the recent SUSY/Higgs Workshop the Higgs Working Group used a method of combining channels and experiments based on the calculation of the joint likelihood for a particular experimental outcome, and averaging over all possible outcomes.},

doi = {},

journal = {},

number = ,

volume = ,

place = {United States},

year = {2000},

month = {5}

}