sPHENIX MAPS tracker discussion

[Anthony Frawley <afrawley AT fsu.edu>]

Hello Xin and All,

Sorry that I have not been following this discussion closely. 

The numbers that you get for the average offset of the MVTX relative to the beam position are significantly smaller than what I get from a Millepede 2 analysis of the silicon track seeds from runs 41989-41992. I find (X0,Y0) ~ (-6.2 mm, +2 mm). It would be good to understand why there is a difference.

It makes a big difference to account for the simulation geometry error in the φ angle offsets between the layers. This is now fixed by default in the offline tracking, because it has been incorporated into the default tracking alignment parameters. To show the importance of this, I attach a plot of the vertex distribution from silicon track seeds after the rotation misalignments and MVTX translations are corrected at the stave level. The axis scale is cm.

Xin, can you add the layer rotation corrections from Yasser and rerun your analysis?

Thanks

Tony

---

From: sphenix-maps-l-request AT lists.bnl.gov <sphenix-maps-l-request AT lists.bnl.gov> on behalf of Xin Dong <xdong AT lbl.gov>
Sent: Thursday, July 4, 2024 1:15 PM
To: Xu-Dong Yu <yuxd AT stu.pku.edu.cn>
Cc: SPHENIX MVTX <sphenix-maps-l AT lists.bnl.gov>
Subject: Re: [[Sphenix-maps-l] ] [Sphenix-maps-l] [EXTERNAL] Re: MVTX meeting next Monday 7/1 12:30PM/ET

 

Hi Xudong,

Thank you very much for digging into this in detail. Your MC test is quite informative and offers quite new insights.

Hi All,

I attach the latest run-dependent beam line center distributions. They look quite stable. Ming, would you bring this up to the operation team and we should make the request to CAD to shift the beam orbit.

Thanks and Best Regards

/xin

On Wed, Jul 3, 2024 at 11:08 PM Xu-Dong Yu <yuxd AT stu.pku.edu.cn> wrote:

Dear all,

According to the private discussion with Xin, i claim that there is no problem in Xin’s calculation. There are some conclusion

1. my derivation is correct, but it is only for 1D case. Stave has finite length in z direction, so we should also consider z-dimensional solid angle coverage. The Jacobian in z or theta direction is the same factor of 1+d/R cos(phi-phi0) which will make this term squared. Due to small quantity of d/R, we can expand it into 1+2d/R cos(phi-phi0) which is Xin’s formula. If stave is infinite length, it will reduce to 1D case without factor of 2. This has been proved by MC simulation.

2. The hits/clusters distribution on z dimension is important. We have tried different emitting particle eta/theta distribution which makes hits/clusters z distribution different from that in data. The result will deviate from the true value according to the MC simulation. In data, z distribution is flat, which ensure then density in different z is the same, and will keep the formula with factor of 2.

3. A example MC simulation is shown below. Three plots are attached.

  1) eta distribution is assumed to be [exp(-eta) + eta(eta)] / 2 and eta region is [-3,3]

  2) hit z distribution in layer 2 which is uniform same with that in data

  3) Fit to the cluster phi distribution w.r.t. mvtx center. The fit formula is Xin’s with factor of 2. The input value of d is 4mm, and the output value of phi0 is 3rad. The output is consistent with input.

4. In software, mvtx center is placed to sPHENIX center (0,0,0), and we only use single mvtx detector information, we can not extract MVTX global translation information. Therefore, my argument about alignment is wrong.

Sorry to bother those who aren't interested in the details.

Best regards,

Xudong

On Jul 3, 2024, at 01:08, Xin Dong <xdong AT lbl.gov> wrote:

Hi Xudong,

The distribution is plotted as a function phi, but for all the clusters integrated over the full z region. While all staves have the same z length, so it will be a constant scaling factor compared to the hit area density distributions on the cylinder surface.

dN/dz will not be a constant as it also depends on the distance to the beam position while this distance scales with the radial distance (rphi direction and z direction are both orthogonal to the radial direction). Thus, the area density dependence will need to be squared then. For clarification, one may run a MC to test it out.

Feel free to ping me offline if you prefer more detailed discussions.

Thanks and Best Regards

/xin 

On Tue, Jul 2, 2024 at 8:06 PM Xudong Yu <yuxd AT stu.pku.edu.cn> wrote:

Dear Xin,

Thanks for your reply. I don't understand why you said "area density", since you fit to 1D phi distribution. Isn't it only a 1D pdf w.r.t. phi? Even if you consider z distribution, it should be dN/dz=1?

For second question, I mean (-8mm, 2mm) is the position of beam position w.r.t. MVTX center,  and MVTX center is not the same as sPHENIX center. As fas as i know, due to installation, MVTX center is about 5mm west to the sPHENIX center.

MVTX center x + (-8mm) = beam x position ≈ vertex x position. And we know that, according to Hao-Ren's vertex distribution, vertex peak at x=-5mm. Therefore, i said it is consistent with vertex distribution. If i am wrong, please correct me.

Best regards,

Xudong

Original:

• From:Xin Dong < xdong AT lbl.gov>
• Date:2024-07-03 10:28:01
• To:yuxd < yuxd AT stu.pku.edu.cn>
• Cc:SPHENIX MVTX < sphenix-maps-l AT lists.bnl.gov>
• Subject:Re: [Sphenix-maps-l] [EXTERNAL] Re: MVTX meeting next Monday 7/1 12:30PM/ET

Hi Xu-Dong,

Thanks for looking into this. The hit density we are looking at here is the area density. At the leading order, there will be another same factor (1+ d/R * cos(phi-phi0)) for dN/dz, therefore, the hit density we are looking at here would be (1 + d/R *cos(phi-phi0)) ^2.  Keeping the leading term, it will become 1 + 2*d/R*cos(phi-phi0). I think you may also run a MC to test it.

I have one question regarding your statement "... (-8mm, 2mm), ... which is consistent with vertex distribution peak position." What do you mean here? And also MVTX center is not necessary to be the sPHENIX center.

Thanks and Best Regards

/xin

On Tue, Jul 2, 2024 at 6:30 PM Xu-Dong Yu <yuxd AT stu.pku.edu.cn> wrote:

Dear Xin,

Thanks for your very nice and very interesting study. I have a comment that maybe your formula has an extra coefficient of 2. After correcting it, beam position w.r.t. MVTX center should be about (X0,Y0) ~ (-8mm,2mm) which is consistent with vertex distribution peak position which is w.r.t. sPHENIX origin. You can see the attached manuscript. If i am wrong, please refute me. Thanks

Best regards,

Xudong

On Jul 2, 2024, at 16:35, Xin Dong via sPHENIX-MAPS-l <sphenix-maps-l AT lists.bnl.gov> wrote:

Hi Joe and HaoRen,

Thanks a lot. The runs after 47002 contain the MVTX cluster phi distributions. The summary of the run dependence can be found below.

<MVTX_BL_run.png>

I see there are more runs appearing in the directory. I can keep updating the figure with more data coming in.

Thanks and Best Regards

/xin

On Tue, Jul 2, 2024 at 12:16 PM Osborn, Joseph <josborn1 AT bnl.gov> wrote:

Hao-Ren is correct. Those files are being aggregated, they are much larger so they take longer to aggregate. But they show up in the same directory under *CLUSTER* instead of *SEED*.

___________________________

Joe Osborn, Ph.D

Physics Department

Brookhaven National Laboratory

josborn1 AT bnl.gov

---

From: Hao-Ren Jheng
Sent: Tuesday, July 2, 2024 3:02 PM
To: Xin Dong
Cc: Osborn, Joseph; SPHENIX MVTX
Subject: Re: [Sphenix-maps-l] [EXTERNAL] Re: MVTX meeting next Monday 7/1 12:30PM/ET

Hi Xin, all,

I think the MVTX cluster QA module is already merged into the coresoftware: https://github.com/sPHENIX-Collaboration/coresoftware/blob/master/offline/QA/Tracking/MvtxClusterQA.cc

Newer runs should have the cluster histograms from the production.

Best,

Hao-Ren

On Jul 2, 2024, at 14:19, Xin Dong via sPHENIX-MAPS-l <sphenix-maps-l AT lists.bnl.gov> wrote:

Hi Joe,

Thanks. I took a look at several root files. It seems the MVTX cluster QA histograms (cluster vs. phi particularly, not associated with tracking, just all clusters) are not saved in these files. Probably we should encourage Hao-Ren to integrate his code updates into the production so we can monitor them along with the run goes.

Thanks and Best Regards

/xin

On Tue, Jul 2, 2024 at 11:05 AM Osborn, Joseph <josborn1 AT bnl.gov> wrote:

You can find many runs produced as a part of the production here:

/sphenix/data/data02/sphnxpro/QAhtml/aggregated/*SEED*

Take a look and let me know if you find issues,

Joe

___________________________

Joe Osborn, Ph.D

Physics Department

Brookhaven National Laboratory

josborn1 AT bnl.gov

---

From: sPHENIX-MAPS-l <sphenix-maps-l-bounces AT lists.bnl.gov> on behalf of Xin Dong via sPHENIX-MAPS-l <sphenix-maps-l AT lists.bnl.gov>
Sent: Tuesday, July 2, 2024 1:58 PM
To: Liu, Ming Xiong <mliu AT lanl.gov>
Cc: SPHENIX MVTX <sphenix-maps-l AT lists.bnl.gov>
Subject: Re: [Sphenix-maps-l] [EXTERNAL] Re: MVTX meeting next Monday 7/1 12:30PM/ET

 

Hi Ming and All,

I looped through all the runs that Hao-Ren generated (actually turns out only 7 runs have the valid entries). Please see the updated slides in the same indico location

https://indico.bnl.gov/event/24069/contributions/93529/attachments/55585/95138/20240701_MVTX_BeamLine.pdf

The run dependence can be found here. It is reasonably stable up to 46677. 

<MVTX_BL_run.png>

Hi Haoren, if you have new production data, feel free to share. 

I also put the macros and figures in the following Git directory.

https://github.com/starsdong/MVTX/tree/main/2024/BeamLine

Comments are very welcome. Thanks and Regards

/xin

On Tue, Jul 2, 2024 at 8:44 AM Liu, Ming Xiong <mliu AT lanl.gov> wrote:

Hi Xin and Hao-Ren,

 

Nice! 

Yes, I agree we should have the beam centered wrt to MVTX for best physics, and we  

 

Hao-Ren, did you use the ideal geometry or the updated one from Yasser’s corrections?  

 

Cheers,

Ming  

 

 

-- 

Dr. Ming Xiong Liu

P-3, MS H846

Physics Division

 

Office: 505.667.7125

Mobile: 505.412.7396

Los Alamos National Laboratory

 

 

From: Xin Dong <xdong AT lbl.gov>
Date: Monday, July 1, 2024 at 11:59 PM
To: Hao-Ren Jheng <hrjheng AT mit.edu>
Cc: Ming Liu <mliu AT lanl.gov>, SPHENIX MVTX <sphenix-maps-l AT lists.bnl.gov>
Subject: [EXTERNAL] Re: [Sphenix-maps-l] MVTX meeting next Monday 7/1 12:30PM/ET

 

Hi All,

 

Thanks Hao-Ren for generating the QA histograms. Based on his root file, I did a quick analysis and please see the findings below

 

https://indico.bnl.gov/event/24069/contributions/93529/attachments/55585/95095/20240701_MVTX_BeamLine.pdf

The slides are also posted to today's MVTX meeting indico page

 

The proposed actions can be found in the last page:

 

1) W.r.t. the condition for the data that Hao-Ren generated, I would propose we request CAD to move the beam orbit at sPHENIX IR horizontally towards x+ direction by 4mm, and if possible, also vertically downwards by 1mm.

 

2) But, the beam position may change, particularly considering recent changes in terms of beam conditions, we should re-analyze the latest beam data and check again.

 

3) We should continue monitoring the beam position throughout the Run. The MVTX cluster phi distributions are a good measure to monitor this.

 

Comments and suggestions are more than welcome. Thanks and best Regards

 

/xin

 

 

On Mon, Jul 1, 2024 at 8:46 PM Xin Dong <xdong AT lbl.gov> wrote:

Hi Hao-Ren,

 

Thank you. I have one question regarding the MVTX cluster phi distribution. You labeled "w.r.t origin". So what origin was used here for the cluster phi angle calculation? If you can clarify, that would be much appreciated.

 

Thanks and Best Regards

 

/xin

 

On Mon, Jul 1, 2024 at 2:41 PM Hao-Ren Jheng <hrjheng AT mit.edu> wrote:

Hi Xin,

 

I just uploaded my slide to the indico page:https://indico.bnl.gov/event/24069/contributions/93529/attachments/55585/95090/MVTXComm-20240701.pdf.

You can find one of the histogram files under my working directory: /sphenix/user/hjheng/sPHENIXRepo/macros/TrackingProduction/HIST_PHYSICS_run2pp_new_2024p001-00046667-0000.root

(You may find the histograms in this file are not the same as the plots I showed in the meeting. I figure a run without any stave missing is more convenient for you to make use of it.)

 

Please let me know if you have any further suggestion to the QA module.

 

Best,

Hao-Ren

On Jul 1, 2024, at 16:22, Xin Dong via sPHENIX-MAPS-l <sphenix-maps-l AT lists.bnl.gov> wrote:

 

Hi Hao-Ren,

 

Could you post your nice QA slides you showed today at the MVTX meeting to indico? Particularly, if you can also share with me the histogram root files for the MVTX layer cluster density distributions vs. phi and the event Vy vs. Vx, I can try to do a quick calculation on the beam position shift w.r.t to the MVTX center and we may feed back to the operation team and make the request.

 

Thanks and Regards

 

/xin

 

 

On Fri, Jun 28, 2024 at 8:39 AM Liu, Ming Xiong via sPHENIX-MAPS-l <sphenix-maps-l AT lists.bnl.gov> wrote:

Dear all,

We will have MVTX meeting next Monday at the usual time, 12:30PM/ET.

• MVTX operation status 
• Offline analysis- raw data QA & monitoring, noise/threshold, alignment etc.
• AOB

 

Draft agenda, https://indico.bnl.gov/event/24069/

 

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Cheers,

Ming 

 

-- 

Dr. Ming Xiong Liu

P-3 Group, MS H846

Nuclear and Particle Physics & Applications

Physics Division

 

Office: 505.667.7125

Mobile: 505.412.7396

Los Alamos National Laboratory

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--

==================================================
Xin Dong
Nuclear Science Division, Lawrence Berkeley National Laboratory
MS70R0319, One Cyclotron Road
Berkeley, CA 94720, USA
Tel: +1-510-486-4121
Email: XDong AT lbl.gov
==================================================

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--

==================================================
Xin Dong
Nuclear Science Division, Lawrence Berkeley National Laboratory
MS70R0319, One Cyclotron Road
Berkeley, CA 94720, USA
Tel: +1-510-486-4121
Email: XDong AT lbl.gov
==================================================

 

--

==================================================
Xin Dong
Nuclear Science Division, Lawrence Berkeley National Laboratory
MS70R0319, One Cyclotron Road
Berkeley, CA 94720, USA
Tel: +1-510-486-4121
Email: XDong AT lbl.gov
==================================================

-- 

==================================================
Xin Dong
Nuclear Science Division, Lawrence Berkeley National Laboratory
MS70R0319, One Cyclotron Road
Berkeley, CA 94720, USA
Tel: +1-510-486-4121
Email: XDong AT lbl.gov
==================================================

-- 

==================================================
Xin Dong
Nuclear Science Division, Lawrence Berkeley National Laboratory
MS70R0319, One Cyclotron Road
Berkeley, CA 94720, USA
Tel: +1-510-486-4121
Email: XDong AT lbl.gov
==================================================

_______________________________________________
sPHENIX-MAPS-l mailing list
sPHENIX-MAPS-l AT lists.bnl.gov
https://lists.bnl.gov/mailman/listinfo/sphenix-maps-l

-- 

==================================================
Xin Dong
Nuclear Science Division, Lawrence Berkeley National Laboratory
MS70R0319, One Cyclotron Road
Berkeley, CA 94720, USA
Tel: +1-510-486-4121
Email: XDong AT lbl.gov
==================================================

_______________________________________________
sPHENIX-MAPS-l mailing list
sPHENIX-MAPS-l AT lists.bnl.gov
https://lists.bnl.gov/mailman/listinfo/sphenix-maps-l

--

==================================================
Xin Dong
Nuclear Science Division, Lawrence Berkeley National Laboratory
MS70R0319, One Cyclotron Road
Berkeley, CA 94720, USA
Tel: +1-510-486-4121
Email: XDong AT lbl.gov
==================================================

--

==================================================
Xin Dong
Nuclear Science Division, Lawrence Berkeley National Laboratory
MS70R0319, One Cyclotron Road
Berkeley, CA 94720, USA
Tel: +1-510-486-4121
Email: XDong AT lbl.gov
==================================================

--

==================================================
Xin Dong
Nuclear Science Division, Lawrence Berkeley National Laboratory
MS70R0319, One Cyclotron Road
Berkeley, CA 94720, USA
Tel: +1-510-486-4121
Email: XDong AT lbl.gov
==================================================

Attachment: vertex.pdf
Description: vertex.pdf