HARP

Collaboration:

- INFN: Bari, Legnaro, Milano, Ferrara, Napoli, Padova, Roma I , Roma III, Trieste
- CERN. Geneva, Switzerland
- Belgium: Louvain-la-Neuve UCL
- Bulgaria: Sofia Academy of Sciences; Sofia University ,
- France: Paris VI-VII University
- Germany: Dortmund University
- Russia: JINR, Dubna; P.N. Lebedev Physical Institute; INR, Moskow; IHEP, Protvino
- Spain: Valencia University
- Switzerland: Geneve University
- United Kingdom: Oxford University; Rutherford Laboratory, Sheffield University

Laboratory and Beam: CERN, CPS protons and pions

National Responsible: V. Palladino (NA)

1 Goal of the Experiment

The HARP experiment is a measurement of hadroproduction, a wide ranging campaign meant to reduce the uncertainties induced by hadroproduction in the field of both accelerator and atmospheric neutrino physics.

The HARP experiment is carrying out, at the CERN PS, a programme of precise measurements of secondary hadrons, over the full solid angle, produced on thin and thick nuclear targets by beams of protons and pions with momentum in the range 2 to 15 GeV/c.

More on the experiment.

2 Activities during 2002

The activity of the Collaboration was focussed on completing the collection of its data, during a data run that took place from early May to early November. All the planned data have been collected with all the foreseen targets material and thicknesses and at all the foreseen beam energies.

In general, all the planned milestones related to hardware & datataking have been fulfilled by the end of the Year 2002:

- Completion of maintenance and repair work for the run in 2002 in the first months of the year.
- Completion of setting up for the run with the help of cosmic ray data early in the spring
- Beginning datataking 2002 in the beam (according to the revised PS schedule that was shifted by a few weeks)
- Completion of datataking in the beam, as of early November.
- Datataking for final calibrations and alignements was almost completely. Only TPC work will have a significant spill over to 2003.
- Completion of dismantling and repatriation of the instrumentation (exception made again for the TPC).

Delay must be acknowledged, however, in the area of data analysis. Our schedule has proven too optimistic and we have been adapting to a somewhat more conventional pace of progress. On one hand, the pressing demand of hardware and datataking effort left very little energies available.On the other, the effort of understanding data quality and detector performances, calibration, evaluation of efficiencies has proven more difficult and time consuming than anticipated. Evaluation and subtraction of cross talk effects among neighbour channels in the main TPC tracker, as well as absolute pad-by-pad recalibration, has also proven necessary. This work is still demanding dedicated attention, now in 2003 and requires also transfer and reinstallation of TPC and its ancillary equipment (magnet, gas system, calibration system etc ) to a neighbouring location in the PS East Hall due to the needs of other users of the Hall. A painful migration from Objectivity to Oracle databases was imposed on us by IT Division policies. The net result will be a significant delay, estimated slightly below one year, with respect to our original hopes for the delivery of both first and final physics results.

Milestones 2003

HARDWARE |
Completion of TPC cross talk measurements | 1-3-2003
Moving of the TPC and its ancillary equipment | 15-6-2003
Completion of TPC recalibration with Mn and Co radioactive sources | 31-7-2003
DATA HANDLING |
Migration of complete 50 TeraByte HARP raw data sample to Oracle | 15-5-2003
FORWARD ANALYSIS |
Completion of realignement of forward detectors | 15-3-2003
Production of n-tuples for detector calibration | 15-4-2003
First complete calibration of forward particle identification detectors (TOF, C, e-id, mu-id) | 30-5-2003
First complete release of forward track reconstruction software | 30-6-2003
First forward DST production | 31-8-2003
First forward results (K2K & MiniBoone and more) | 31-10-2003
LARGE ANGLE ANALYSIS |
Definition of TPC cross talk subtraction algorithms: first results | 30-6-2003
Completion of analysis of TPC calibration data | 30-9-2003
Release of complete large angle (TPC & RPC) reconstruction software | 15-10-2003
First large angle DST | 31-10-2003
First large angle results | 15-12-2003

3 INFN contribution to the experiment

Manpower:

INFN contributes to the experiment about 1/3 of is manpower, with 38 researchers (17.7 FTE) supported by their mechanical and electronics workshops.

Budget for the Year 2003: 1.1% of the total CSNII budget

4 Number of publications in refereed journals (in 2002): 0
5 Number of talks to conferences (in 2002): 2

6 Number of thesis on HARP:

- 4 undergraduate thesis
- no doctoral thesis

7 Leadership roles in the experiment

U. Gastaldi (LNL) is driving the process of full understanding and recalibration of the TPC and E. Radicioni (BA), responsible of HARP DAQ from its realization, carries the large majority of the related responsability in the experimental areas and counting room. INFN groups have large responsabilities in all aspects of software. M. G. Catanesi (BA) is responsible for Large Angle (TPC & RPC) Reconstruction & Analysis. A. Guglielmi (PD), M. Apollonio (TS), D. Orestano (Roma3) are responsible for the software and reconstruction of respectively TOF, Cerenkov, e-identifier. A. Demin (PD) presented the last HARP status report to plenary SPSC and M. G. Catanesi the last report to the SPSC referees.

8 Innovative instruments

The TPC , including its electronics , is a first class modern device, thriving on the experience of the ALEPH and ALICE TPC¤s,among many others.
The DAQ uses a modern LHC-era architecture: it features the possibility of storing raw data in object-oriented format and it is able to read out the TPC at the unprecedented rate of 3KHz. HARP was one of the first experiment that adopt modern software-engineering procedures and an architectural Object-Oriented design was worked out.
All subdetectors are state-of-the-art devices.

9 Competitive experiments: Experiment E910 (R. Raja et al) is preparing datataking in the Meson Lab at Fermilab. It holds comparable promise. Reciprocal validation with HARP will hopefully strenghten our hold on hadronic uncertainties in neutrino physics.

10 International reviews

HARP was reviewed and approved by the CERN SPSC and Research Board. Progress (through construction, datataking and now data analysis) is kept under close scrutiny by all these committees by means of very frequent oral and/or written status reports.