# The 2009 Europhysics Conference on High Energy Physics

Jul 16 – 22, 2009
Kraków, Poland
Europe/Warsaw timezone

## Search for single top production at HERA

Jul 16, 2009, 3:49 PM
15m
Middle Lecture Hall A (Kraków, Poland)

### Middle Lecture Hall A

#### Kraków, Poland

The Auditorium Maximum of the Jagiellonian University 33 Krupnicza Street 31-123 Kraków
Standard Model Electroweak Physics

### Speaker

Dr Lorenzo Bellagamba (INFN Bologna)

### Description

Searches for single-top production at the $ep$ collider HERA has been performed using data collected by the H1 and ZEUS Collaborations. The H1 collaboration analyzed the full HERA data sample corresponding to an integrated luminosity of 474 pb^-1 looking both at the leptonic and hadronic decay of the W coming from top decay. The ZEUS collaboration analyzed data collected in the running period 2004-2007 corresponding to an integrated luminosity of 277 pb^-1 looking at the leptonic W decay. New ZEUS results have been also combined with a previous search performed with data collected in 1998-2000 for a total integrated luminosity of 359 pb^-1. The results of the searches have been used to constrain single-top production via flavour changing neutral current (FCNC) transitions. In case of u-t transition mediated by a photon, the HERA constraints are the best to date.

### Primary author

Dr Lorenzo Bellagamba (INFN Bologna)

### Presentation materials

 bellagamba.pdf bellagamba.ppt