# Presentation: 945301

## MERIT Status  

**     ****NFMCC Collaboration Meeting**
**                        ****FNAL**
**             ****March  17-20, 2008**

## The Collaborating Institutions

**U.S.**
**         ****	****Brookhaven National Laboratory**
**	****Fermi National Accelerator Laboratory**
**     ****	****Oak Ridge National Laboratory**
**	****Princeton**
**Europe**
**	****CERN**
**	****Rutherford Appleton Laboratory**

## MERIT Experiment in the TT2a Area

- Solenoid  & Hg loop

- Upstream beam elements (new)
- Quadrupoles for final focusing
- Collimator
- Beam profile measurement
- Beam intensity measurement

- Beam dump

- Racks & electronics

- N2 Exhaust line

- Material access shaft

- Personnel access

## The Pump/Probe Detectors 

- M. Palm, CERN - AB/ATB/EA

**The Pump/Probe Detectors**** **

- ACEM (Aluminum Cathode Electron Multiplier)Diamond

- +/- 10 degrees

- +/- 20 degrees

- In beam line, upstream of target

- Behind dump in beam line

## Sectional view of the MERIT Experiment

**Sectional view of the MERIT Experiment**

**Beam**
**Window**

**Hg Jet**

## Profile of the Experiment

-  **14 and 24 GeV proton beam**
** ****Up to 30 x 10****12**** protons (TP) per 2.5********s spill**
** ****Proton beam spot with r ****≤ 1.5 mm rms**
** ****1cm diameter Hg Jet**
** ****Hg Jet/proton beam off solenoid axis**
**  ****Hg Jet 33 mrad to solenoid axis**
**  ****Proton beam 67 mrad to solenoid axis**
** ****Test 50 Hz operations**
** ****20 m/s Hg Jet**

## Proton Beam Characteristics

-   **PS was run in a harmonic 4, 8, and 16 mode**
** ****Fast extraction can accommodate entire 2.5 ********s PS fill.**
** ****Full single turn extraction at 24 GeV**
** ****Partial/multiple extraction possible at 14 GeV**
** ****First Beam on Target ****October 17 2007**

## MERIT Beam Shots

**MERIT Beam Shots**

- 30 x 1012 protons/pulse!!!
-  24 GeV
-  115kJ !!! a PS record

## A 3TP Pump Pulse and a 1TP Probe Pulse

**A 3TP Pump Pulse and a 1TP Probe Pulse**
**                ****with 1ms delay**

## 15TP 14GeV Proton Beam

**Beam 5016, Hg 15m/s,  100****μ****s/frame, Total 1.6ms**

**Oct. 27, 2007**
**Solenoid Field **
**at 5T**
**Viewport 2**

**15TP 14GeV Proton Beam**

## Viewport 3: Jet/proton interaction

**Viewport 3: Jet/proton interaction**

**Shot 16014**
** ****14 GeV**
** ****12x10****12**** protons/pulse**
** ****B-field 10 T**
** ****500****μ****s/frame**

**Disruption Length =16.5cm**

******cm**

## Influence of B-field on Jet Disruption

## The 24 GeV 30TP shot

**Beam pulse energy = 115kJ**
**B-field = 15T**
**Jet Velocity = 20 m/s**
**Disruption Length = 16 cm**
**We will replace 2 interaction lengths (28cm)**
**Then the jet transport time is 28cm/20m/s = 14ms**
**Rep rate of 70Hz**
**Proton beam power at that rate is 115kJ *70 = 8MW **

## 4TP + 4TP Delay Study:14 GeV 7T

**Single Turn Extraction**
****** ****0 Delay**

**4TP Probe extracted on **
**subsequent turn**
** ******** ****3.2 ****μ****s Delay**

**4TP Probe extracted **
**after 2nd full turn**
** ******** ****5.8 ****μ****s Delay**

**Target supports 14 GeV 4TP beam at 172kHz rep rate without disruption**

## Decommissioning

-  **Optics has been shipped to BNL**
** ****Pulsed Solenoid ready to be removed from TT2a**
** ****Hg Injection System**
**Hg removed to shipping vessels**
**200 ml of Hg spilled and cleaned up (floor to be repainted)**
**Hydraulic fluid removed to shipping barrel**
** ****Solenoid and Injection System to be removed from TT2a within next 2 weeks**
** ****Solenoid, Cryo-system, Hg Injection system to be shipped to U.S. January 09**

## Data Analysis Activities

**Disruption threshold based on proton beam characteristics**
**	****Intensity variations**
**	****Proton beam harmonic structure**
**Disruption threshold based on solenoid field strength**
**Pump/probe studies**
** ****	****15TP pump + 5TP probe with delays 2 to 700****μ****s**
**	****24 GeV pump/probe studies with delays < 2****μ****s**
**Magnetohydrodynamic studies**
** ****	****Disruption (filamentation) velocities**
**	****Quadruple distortions**
**Proton beam spot size analysis**

## More MERIT Reports to Follow

**Optical Diagnostic Results       ****	****HeeJin Park**
**MERIT Simulations ****	****	****	****Sergei Striganov**