# Comparison of ZEUS data with standard model predictions for e{sup +}p {yields} e{sup +}X scattering at high x and Q{sup 2}.

## Abstract

Using the ZEUS detector at HERA, we have studied the reaction e{sup +} {rho}{yields} e{sup +}X for Q2 > 5000 GeV2 with a 20.1 pb-1 data sample collected during the years 1994 to 1996. For Q2 below 15000 GeV2, the data are in good agreement with Standard Model expectations. For Q2 > 35000 GeV2, two events are observed while 0.145 {+-}0.013 events are expected. A statistical analysis of a large ensemble of simulated Standard Model experiments indicates that with probability 6.0%, an excess at least as unlikely as that observed would occur above some Q2 cut. For x > 0.55 and y > 0.25, four events are observed where 0.91{+-}0.08 events are expected. A statistical analysis of the two-dimensional distribution of the events in x and y yields a probability of 0.72% for the region x > 0.55 and y > 0.25 and a probability of 7.8% for the entire Q2 > 5000 GeV2 data sample. The observed excess above Standard Model expectations is particularly interesting because it occurs in a previously unexplored kinematic region.

- Authors:

- Publication Date:

- Research Org.:
- Argonne National Lab. (ANL), Argonne, IL (United States)

- Sponsoring Org.:
- ER

- OSTI Identifier:
- 938399

- Report Number(s):
- ANL-HEP-PR-98-57

Journal ID: ISSN 0170-9739; ZPCFD2; TRN: US200908%%328

- DOE Contract Number:
- DE-AC02-06CH11357

- Resource Type:
- Journal Article

- Journal Name:
- Z. Phys. C

- Additional Journal Information:
- Journal Volume: 74; Journal Issue: 2 ; 1997; Journal ID: ISSN 0170-9739

- Country of Publication:
- United States

- Language:
- ENGLISH

- Subject:
- 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; DISTRIBUTION; PROBABILITY; SCATTERING; STANDARD MODEL

### Citation Formats

```
Breitweg, J., Derrick, M., Krakauer, D., Magill, S., Mikunas, D., Musgrave, B., Repond, J., Stanek, R., Talaga, R. L., Yoshida, R., Zhang, H., ZEUS Collaboration, and High Energy Physics.
```*Comparison of ZEUS data with standard model predictions for e{sup +}p {yields} e{sup +}X scattering at high x and Q{sup 2}.*. United States: N. p., 1997.
Web. doi:10.1007/s002880050384.

```
Breitweg, J., Derrick, M., Krakauer, D., Magill, S., Mikunas, D., Musgrave, B., Repond, J., Stanek, R., Talaga, R. L., Yoshida, R., Zhang, H., ZEUS Collaboration, & High Energy Physics.
```*Comparison of ZEUS data with standard model predictions for e{sup +}p {yields} e{sup +}X scattering at high x and Q{sup 2}.*. United States. doi:10.1007/s002880050384.

```
Breitweg, J., Derrick, M., Krakauer, D., Magill, S., Mikunas, D., Musgrave, B., Repond, J., Stanek, R., Talaga, R. L., Yoshida, R., Zhang, H., ZEUS Collaboration, and High Energy Physics. Wed .
"Comparison of ZEUS data with standard model predictions for e{sup +}p {yields} e{sup +}X scattering at high x and Q{sup 2}.". United States. doi:10.1007/s002880050384.
```

```
@article{osti_938399,
```

title = {Comparison of ZEUS data with standard model predictions for e{sup +}p {yields} e{sup +}X scattering at high x and Q{sup 2}.},

author = {Breitweg, J. and Derrick, M. and Krakauer, D. and Magill, S. and Mikunas, D. and Musgrave, B. and Repond, J. and Stanek, R. and Talaga, R. L. and Yoshida, R. and Zhang, H. and ZEUS Collaboration and High Energy Physics},

abstractNote = {Using the ZEUS detector at HERA, we have studied the reaction e{sup +} {rho}{yields} e{sup +}X for Q2 > 5000 GeV2 with a 20.1 pb-1 data sample collected during the years 1994 to 1996. For Q2 below 15000 GeV2, the data are in good agreement with Standard Model expectations. For Q2 > 35000 GeV2, two events are observed while 0.145 {+-}0.013 events are expected. A statistical analysis of a large ensemble of simulated Standard Model experiments indicates that with probability 6.0%, an excess at least as unlikely as that observed would occur above some Q2 cut. For x > 0.55 and y > 0.25, four events are observed where 0.91{+-}0.08 events are expected. A statistical analysis of the two-dimensional distribution of the events in x and y yields a probability of 0.72% for the region x > 0.55 and y > 0.25 and a probability of 7.8% for the entire Q2 > 5000 GeV2 data sample. The observed excess above Standard Model expectations is particularly interesting because it occurs in a previously unexplored kinematic region.},

doi = {10.1007/s002880050384},

journal = {Z. Phys. C},

issn = {0170-9739},

number = 2 ; 1997,

volume = 74,

place = {United States},

year = {1997},

month = {1}

}