# Presentation: 415394

## NA48 Future Plans

**RHIC & AGS Annual Users Meeting - Brookhaven**
**Giuseppe Ruggiero **
**University of Firenze**
- On behalf of NA48 – Future Working Group

- Giuseppe Ruggiero

## Outline

**From the address of Aymar (CERN CEO) 13/1/2004:**

***“******...***
**Another goal [for 2004-2010] would be: ****to define possible new fixed-target experiments ****(praised in another Cogne* meeting in September 2004).**
**To decide**** ****in 2006 ****(...) any proposed R&D or ****experiment**** depending on the ****funds available or expected ****at that time.**
***...”***

***Cogne=Villars**

- Giuseppe Ruggiero

## Proposal (NA48/3)

**NA48 detector upgrading to study**
**         **
**High Physical potential**
**Aim to a 10 % measurement of                                  **
**Availability of experimental infrastructures (NA48/2):**
**Location for the experiment (ECN3 – high radiation area)**
**Beam line (**_***high intensity***_**, slowly extracted protons from SPS)**
**Subdetectors (e.g. LKr calorimeter)**
**2004 run (beam test)**
**Goal:**
_***About 50 Events with a S/B of 10:1 in 2 years of data taking ***_

**CERN–SPSC–2004–010  / SPSC–EOI–002  **

- Giuseppe Ruggiero

## Experimental features

**Experimental features**

**decay in flight**

**High energy**

**Region I**

**Region II**

**Super-rare decay:**
**BR ~ 10********10**

** ****Kinematical cuts**
** ****Veto systems**
** ****Particle ID**

- Giuseppe Ruggiero

## Experimental Layout

***Vacuum***

- Giuseppe Ruggiero

## Beam Layout

**Beam line:**
**Unseparated**** positive                        beam **
** ****P = 75 GeV/c,  ********P/P ~ 1%     ****(P****p****= 400 GeV/c**** ****)**
**Beam detectors:**
**Differential Cerenkov detector (CEDAR) **
**Tag Kaons (made blind to ********+ ****and p)**
**Beam spectrometer (KABES): **
**Redundant measurement of beam momentum**
**Measurement of the kaon direction**

**Micromega-type chambers (already employed in NA48/2)**
**Silicon – pixel detector**

- Giuseppe Ruggiero

## Beam Layout 

**Beam-line **
**102 m long**

**about 17%**
**K****+ ****lost**

**Dipoles**

**Dipoles**

- Giuseppe Ruggiero

## New high-intensity beam (1)

| BEAM | NA48/2 | NA48/3 | Factor |
| --- | --- | --- | --- |
| SPS protons per pulse | 1x1012 | 3x1012 | 3 |
| Duty cicle (s/s) | 4.8/16.8 |  | 1 |
| Beam acceptance (mrad) |  |  |  |
| Solid angle ( sterad) | 0.40 | 16 | 40 |
|  | 60 | 75 | 1.35 |
| 
RMS (P/P  %) | 6
4 | 1.5
0.95 | 0.375
0.25 |
| Beam size (cm)
Area at KABES (cm2) | 
7.0 | 
20 | 2.8 |
| Divergence (mrad) | 0.05 | 0.1 | 2 |

- Giuseppe Ruggiero

## New high-intensity beam (2)

| BEAM | NA48/2 | NA48/3 | Factor |
| --- | --- | --- | --- |
| Decay fiducial length () | 50 m  (0.11) | 50 m  (0.09) | (0.8) |
| Beam flux / pulse 
           p (x 107)
K+
+
e+ | 
0.86
0.31
3.32
0.95 | 
49
15
150
35 | 

50
45 |
| Total per pulse (x 107)
per spill lentgh (MHz)
 @ KABES / cm2 (MHz) | 5.5
18
2.5 | 250
800
40 | 45
45
16 |
| Eff. Run time / days | 0.5 x 120 | 2/3 x 90 | 1 |
| K+  decays per year 
(inside fiducial length)  | 1 x 1011 | 4 x 1012 | 40 |

- Giuseppe Ruggiero

## Cerenkov (CEDAR)

**K/******

**Cedar-W**

**Cedar-N**

**Test foreseen during 2004 run**

** ****Cerenkov differential counter**
** ****Highly parallel beam**

- Giuseppe Ruggiero

## Kaon Spectrometer (KABES)

**Kaon Spectrometer (KABES)**

**Currently used in NA48/2 **
**@ 2 MHz/strip**

** ****Resolution strips    80 ********m**
** ****Resolution drift      50 ********m**
** ****Time resolution      0.7 ns **
** ****Dead time/strip      40 ns**
** ********P/P                           0.5 %**

** ****Improvement for NA48/3 **
**(expected**** ****20 MHz/strip)**

** ****New micro-mesh  25 ********m**
** ****New gas**
** ****FADC **
** ****Smaller strip size**
** ****Si micro-pixels (sub-ns time resol.)**

**Old NA48 Tagger readout (1 GHz FADC) **

**Test foreseen during 2004 run**

- Giuseppe Ruggiero

## Detector Layout

**Subdetectors downstream the beginning of the fiducial region:**
**Double spectrometer**
**6 drift chambers (4 chambers already employed in NA48)**
**2 magnet (1 magnet already employed in NA48)**
**Momentum redundant measurements**
**Photon veto: **
**LKr calorimeter (already in NA48) + charged particle sweeping magnet**
**2 small angle vetoes (CMS prototypes)**
**8 rings as large angle vetoes (upgrade of AKL detectors in NA48)**
**Hadron calorimeter**
**Muon veto**

- Giuseppe Ruggiero

## Detector Layout

**Detector Layout**

- Giuseppe Ruggiero

## Kinematical rejection

**Events accepted**

- Region I

**Measured quantities**

- Giuseppe Ruggiero

## Acceptance

**20 events per year**
**@ BR = 10 ****-10**** (Region I)**

**Acceptance**

**Acceptance**

**Region I**

**Region II**

- 75 GeV/c

- Giuseppe Ruggiero

## Double spectrometer layout

**Double spectrometer layout**

**DCH1**

**DCH2**

**DCH3**

**DCH4**

**DCH5**

**DCH6**

**Kevlar**

**Mag1**

**Mag2**

***z***

***x***

**Vacuum**

**He**

**NA48 Wire chambers 0.004 X****0**

**Kevlar**

***z***

***x***

**Vacuum**

**He**

**NA48 Wire chambers 0.004 X****0**

**Straw tube 0.0025 X****0**

- Giuseppe Ruggiero

## Double spectrometer performance

**DCH1 in**
**vacuum**

**Single **
**configuration**

**Double**
**configuration**

**Two independent measurement of P******

**Simulation with gaussian MS**

**  ****Much higher intensity on **
**     ****DCH in NA48/3  **

**Intensity and performance **
**vs HV tests**
**foreseen in 2004 run**

****

- Giuseppe Ruggiero

## Photon rejection

**KAMI**

**KAMI**

** ****Aim to reach 10****-6**** inefficiency**
** ****For P********< ****40 GeV/c there are at least 35 GeV/c in the e.m. calorimeters**

** ****Plans to study**** **_**our inefficiency**_** (LKr calorimeter + small angle veto) **
**    ****by collecting a large sample of ********************events in 2004 run**

- Giuseppe Ruggiero

## Small angle photon veto

**PbWO****4 **** crystals (CMS)**
** ****Dimension of crystals **
**    ****2x2x23 cm****3****                                        **
** ****7 x 7 cm matrix**
** ****~ 25 X****0**
** ****Readout with light **
**    ****guides and PMT**
** ****Hard to radiation **
**    ****damage **

**Low intensity hermetic**
**photon veto test foreseen **
**in 2004 run**

- Giuseppe Ruggiero

## Muon rejection

**Better than 10****-5**** rejection inefficiency mandatory**
** ****10****-5 ****obtained by NOMAD**
**Present detector **_**not enough efficient**_
**    ****(5****x****10****-3**** inefficient)**
**3 scintillator arrays separated by iron planes 80 cm thick.**
**We are planning to build a new detector**
**     ****(Hadron calorimeter + muon detector)**

- Giuseppe Ruggiero

## Tests in 2004 run

**Muon sweeping**
**CEDAR ****(with COMPASS collaboration)**
**KABES (micromega):**
**FADC readout**
**25 ********m mesh**
**Si pixel chip**
**High Intensity DCH test**
**Low intensity hermetic  ********-veto test**

- Giuseppe Ruggiero

## Conclusions

**We are working on the upgrade of the NA48  detector to study the                        decay.  **
**We have established a Working Group.**
**Fundamental tests foreseen in 2004 run.**
**We plan to contribute to the Villars SPSC meeting (22-28 september).**

- Giuseppe Ruggiero