Quartet Meeting in Paris

7 Nov 2022, 09:00 → 8 Nov 2022, 13:55 Europe/Zurich

room 210 (Laboratoire Kastler Brossel)

Monday 7 November

Welcome and Overview

Reminder of QUARTET goals, timeline, and goals for meeting

Convener: Nancy Paul (Laboratoire Kastler Brossel)

1 Report on recent MuX results and status of PSI beamline

Speakers: Frederik Wauters (Johannes Gutenberg University Mainz), Katharina von Schoeler (PSI - Paul Scherrer Institut)

Lithium2022.pdf

muXforMMCParis.pdf

What can we learn and use from MuX experience and equipment?

 

1. MuX have been measuring Muonic x-rays with a ton of Germanium detectors for a while.
    
2. One lesson learned: Don't be your setup in lead! because electrons from muon decay will radiate
    
3. Rise time of Germanium detectors is order 100ns, and MuX are experienced in reading the timing of each signal.
    
4. For High Z nuclei, the muon energy is of order of nuclear excited states, making the analysis messy. Lesson is we should look into the energy scale of excited states of our nuclei. Although it looks complex, but there are not many free parameters.
    
5. In 2019, they showed that they can keep a large system running for 7 weeks.
    
6. They learned it is hard to hold a beamtime with long shifts at PSI. And what helps is sharing resources.
    
7. MuX runs at Pie1, which is where we will probably end up in a test beamtime
    
8. You always have electrons with the same momentum as Michelle electrons.
    
9. The Pie1 beam is about 2x2 cm.
    
10. July is a good time to come and prepare. We should discuss at what stage to crane in.
     
11. Stuff from MuX that can maybe be used: HPGes, DAQ, slow control, tagging detector, electron detectors.
     
12. MIDAS can be controlled from outside PSI.
     
13. You want to stay light in the materials around the target. 

%%% Katharina's talk

 

1. Active area of SD is 70mm^2, and detector thickness is 500um. Be window thickness 12.5um.
    
2. Lithium targets in aluminum-plastic pouch.
    
3. Rough calibration with 55Fe, 241Am, 109Cd
    
4. 5 hours measurement time.
    
5. Seeing lines from C, Al, Nitrogen (background)
    
6. 8000 counts in 2p-1s in 5 hours. 2-3eV in 5 hours in few Hz.

 

2 Moments of the charge distribution

Speaker: Ben Ohayon (ETH Zurich)

Moments of the charge distribution.pdf

--Differences in languages coming from both light and heavy radius analysis, and also from nuclear and atomic physicists

--Non trivial comparison between muonic atoms and electron scattering

--The RMS charge radius is the first term of the FF expansion

--the SOG or FB doesn't really work with low Q2, Randolf says it's all bullshit, extremely difficult to get reliable charge radii from electron scattering---> this is why we need muonic atom spectroscopy

 

-muonic atoms measure something like the Barrett radius, transition dependent

-angeli paper has no uncertainties

-Ben has been recalculating the radii with v-factor analysis combining muonic and electron scattering with bootstrapped uncertainties

 

-Who has access to Ingo Sick's data ? 

 

--Paul has a good recipe where he tested the effect of the nuclear charge distribution for 12C, should be published and redone for other elements

--Randolf used a gaussian charge distribution, but it didn't really matter because the TPE limited everything, the different coefficients don't have a big effect on the RMS charge radius.

 

--measure the slope of the FF at q2=0, we call it radius.

--Convince Paul to publish his analysis of 12C and extend the methodology to other nuclei

 

 

 

 

12:10 Lunch

How to measure?: Needs for MMC before beamtime--calibration, testing

Plan experimental setup for 2023

Convener: Andreas Fleischmann

2022-11-07 Setup.pdf

MMCs_for_Exotic_Atoms.pdf

MMCs_for_Exotic_Atoms.pptx

1. The signal size is a function of the bath temperature. They record the temperature for each event and correct for the fluctuations.
    
2. Some events make a peak to the left of the main line. Could be improved.
    
3. The rise time would be around a microsecond in our application
    
4. Order of few ms of decay time is a good compromise for low rate experiments like ours.
    
5. The signal analysis is not so sensitive to the filtering mechanism.
    
6. For the MaXs-20, can see up to 60keV but the resolution deteriorates above 10keV.
    
7. For the larger detectors, the response is more linear.
    
8. When averaging out pixel, it is typically ok to sum up scaled pixels.
    
9. MaXs-100, is 10x10, around 40eV resolution. can go up to around 200keV.
    
10. Takes about 2.5 days between disassembling at Heidelberg and pressing "start" at GSI.
     
11. Some calibration linecenters depend on the chemistry. They like gamma lines, which some to agree to around 0.5eV.
     
12. The deviation from better calibration are ascribed to effects of ADC nonlinearity. 
     
13. There may be better ADC around. 
     
14. "in principle you can eliminate this problem on a voltage level".
     
15. This limits the ability to do "sparse calibration". We probably need close calibration lines until ADC upgrade.

 

Setup:
 

1.  

 

 

3 Lessons learned with TES detectors at J-PARC

Speaker: Nancy Paul (Laboratoire Kastler Brossel)

1. By choosing the correct calibration lines, can be known to 10meV...!

How to measure?: Experimental setup at PSI

Plan experimental setup for 2023

Convener: Andreas Knecht (Paul Scherrer Institut)

2022-11-07 Setup.pdf

MMCs_for_Exotic_Atoms.pdf

MMCs_for_Exotic_Atoms.pptx

1. The signal size is a function of the bath temperature. They record the temperature for each event and correct for the fluctuations.
    
2. Some events make a peak to the left of the main line. Could be improved.
    
3. The rise time would be around a microsecond in our application
    
4. Order of few ms of decay time is a good compromise for low rate experiments like ours.
    
5. The signal analysis is not so sensitive to the filtering mechanism.
    
6. For the MaXs-20, can see up to 60keV but the resolution deteriorates above 10keV.
    
7. For the larger detectors, the response is more linear.
    
8. When averaging out pixel, it is typically ok to sum up scaled pixels.
    
9. MaXs-100, is 10x10, around 40eV resolution. can go up to around 200keV.
    
10. Takes about 2.5 days between disassembling at Heidelberg and pressing "start" at GSI.
     
11. Some calibration linecenters depend on the chemistry. They like gamma lines, which some to agree to around 0.5eV.
     
12. The deviation from better calibration are ascribed to effects of ADC nonlinearity. 
     
13. There may be better ADC around. 
     
14. "in principle you can eliminate this problem on a voltage level".
     
15. This limits the ability to do "sparse calibration". We probably need close calibration lines until ADC upgrade.

 

Setup:
 

1.  

 

 

16:25 Coffee

What will we measure?: Theoretical contributions to systematics and uncertainties

4 Discussion on letter of interest

Speaker: Andreas Knecht (Paul Scherrer Institut)

2022-11-07 LOI.pdf

1. Put the global physics not for the first test beamtime.
    
2. Can use Martiyenko's paper and scale 2S by 8 to 1S
    
3. Have to think of the timeline.
    
4. Collaboration: as we will use a lot of technology from MuX, we should offer some of them to join.
    
5. Available PhD. from Nancy.
    
6. Spokesperson(s): Nancy and Ben in the beginning. 
    
7. Andreas suggests a Board

What will we measure?: Experimental contributions to systematics and uncertainties

Discussion

19:00 Drinks and Dinner--LE PETIT PONTOISE

9 Rue de Pontoise
75005 Paris, France

http://www.lepetitpontoise.fr/

Tuesday 8 November

5 Funding for 2023 and beyond

Speakers: Ben Ohayon (ETH Zurich), Frederik Wauters (Johannes Gutenberg University Mainz), Nancy Paul (Laboratoire Kastler Brossel)

Structure of Test beam time request

Convener: Andreas Knecht (Paul Scherrer Institut)

6 Planning and to-do list

Distribution of tasks for LOI to request test beam in 2023

Speaker: Nancy Paul (Laboratoire Kastler Brossel)