- Welcome to Beam Diagnostics Forum (beamdiag.net).
Diagnostics for Electron beam of light sources
Recent posts
#41
General Discussion / Re: BPM system in different in...
Last post by Laura - September 30, 2021, 03:39:11 PMHello,
At ALBA we have in total 120 BPMs (Libera Brilliance) in the storage ring and we use 88 for feedback to have squared matrix, since we have 88 correctors (WEPD23 https://www.slac.stanford.edu/econf/C140914/papers/wepd23.pdf).
They are doing quite well after ~ 10 years operation but this year fans started to fail consistently and we decided to perform a full replacement campaign.
We are also testing 2 Libera Brimmiance+ and Libera Spark+Pilot-tone in some special BPMs.
In the Booster, we have 44 BPMs, 24 of them are equipped with a Libera Brilliance but we really only use 8. One BPM (the first after injection) is equipped with a Libera Spark Single pass and we use it for Linac to Booster injection efficiency measurements.
In the Linac and in the transfer lines we iindeed use Libra Spark Single Pass (Upgrade of BPMs and SRMs for the ALBA Booster to Storage Ring transfer line, DEELS 2017 https://www.synchrotron-soleil.fr/fr/evenements/deels-diagnostics-experts-european-light-sources).
At ALBA we have in total 120 BPMs (Libera Brilliance) in the storage ring and we use 88 for feedback to have squared matrix, since we have 88 correctors (WEPD23 https://www.slac.stanford.edu/econf/C140914/papers/wepd23.pdf).
They are doing quite well after ~ 10 years operation but this year fans started to fail consistently and we decided to perform a full replacement campaign.
We are also testing 2 Libera Brimmiance+ and Libera Spark+Pilot-tone in some special BPMs.
In the Booster, we have 44 BPMs, 24 of them are equipped with a Libera Brilliance but we really only use 8. One BPM (the first after injection) is equipped with a Libera Spark Single pass and we use it for Linac to Booster injection efficiency measurements.
In the Linac and in the transfer lines we iindeed use Libra Spark Single Pass (Upgrade of BPMs and SRMs for the ALBA Booster to Storage Ring transfer line, DEELS 2017 https://www.synchrotron-soleil.fr/fr/evenements/deels-diagnostics-experts-european-light-sources).
#42
Need help? / Re: Coupling Synchrotron Radia...
Last post by Johannes Steinmann - September 20, 2021, 05:34:44 PMDear Kees and Ji-Gwang,
thanks much for your comments.
We will not be able to avoid setting up a test setup in the lab. If we find something useful you will hear about it ;-)
Cheers,
Johannes
thanks much for your comments.
Quote from: Ji-Gwang Hwang on September 17, 2021, 11:56:25 AMThis is an option we did not think about. Thanks!
[...] we tried a proof-of-principle using a liquid light guide (something like: https://www.edmundoptics.com/f/liquid-light-guides/11425) at an optical table with SR since the liquid cable has a large inlet aperture, high transmission, and a large numerical aperture (for easy coupling).
We will not be able to avoid setting up a test setup in the lab. If we find something useful you will hear about it ;-)
Cheers,
Johannes
#43
Need help? / Re: Coupling Synchrotron Radia...
Last post by Ji-Gwang Hwang - September 17, 2021, 11:56:25 AM Dear Johannes
Our group had the idea to couple SR light into an optical fiber to convey the light to a fast photodiode (with an active area of 200 um^2) and we tried a proof-of-principle using a liquid light guide (something like: https://www.edmundoptics.com/f/liquid-light-guides/11425) at an optical table with SR since the liquid cable has a large inlet aperture, high transmission, and a large numerical aperture (for easy coupling).
In the test, the transmission was okay and input coupling was easy since that light guide has a large aperture.
But it is difficult to get proper outcoupling optics for the small active area. Due to the large NA, the light is quickly diverse and then it demands a lens close to the output port of the light guide. But this leads to a small magnification that causes the loss of a lot of light intensity. I guess this is the same issue for the streak camera.
Best regards
Ji-Gwang Hwang
Our group had the idea to couple SR light into an optical fiber to convey the light to a fast photodiode (with an active area of 200 um^2) and we tried a proof-of-principle using a liquid light guide (something like: https://www.edmundoptics.com/f/liquid-light-guides/11425) at an optical table with SR since the liquid cable has a large inlet aperture, high transmission, and a large numerical aperture (for easy coupling).
In the test, the transmission was okay and input coupling was easy since that light guide has a large aperture.
But it is difficult to get proper outcoupling optics for the small active area. Due to the large NA, the light is quickly diverse and then it demands a lens close to the output port of the light guide. But this leads to a small magnification that causes the loss of a lot of light intensity. I guess this is the same issue for the streak camera.
Best regards
Ji-Gwang Hwang
#44
General Discussion / Re: BPM system in different in...
Last post by Benoît Roche - September 16, 2021, 11:00:17 AMThanks Lorraine, I added your contribution to the list.
I see that you plan to upgrade the performances of your Fast Orbit Feedback quite a bit! Increasing the correction bandwidth by a factor 7 is not negligible.
It's a good time to join your team to work on this new and exciting project
I see that you plan to upgrade the performances of your Fast Orbit Feedback quite a bit! Increasing the correction bandwidth by a factor 7 is not negligible.
It's a good time to join your team to work on this new and exciting project
#45
Need help? / Re: Coupling Synchrotron Radia...
Last post by Kees Scheidt - September 16, 2021, 10:34:14 AMHi Johannes,
I read and understand your problem, and I think your approach of using a fiber to get the light from the tunnel
to your lab is feasible, but I have no direct experience with it. Stay in touch, and share your future experience,
it is certainly relevant.
I read and understand your problem, and I think your approach of using a fiber to get the light from the tunnel
to your lab is feasible, but I have no direct experience with it. Stay in touch, and share your future experience,
it is certainly relevant.
#46
Need help? / Coupling Synchrotron Radiation...
Last post by Johannes Steinmann - September 16, 2021, 09:34:17 AMHi all,
in our booster we can't install a streak camera / beam line. So, we are thinking about coupling light from a view port into a fiber and transport it to the streak camera (~20m). Does someone have experience with coupling bending magnet radiation into a fiber? Which coupler to use, how to focus, which fiber, which frequency (range)?
I appreciate any suggestions.
Thanks,
Johannes
in our booster we can't install a streak camera / beam line. So, we are thinking about coupling light from a view port into a fiber and transport it to the streak camera (~20m). Does someone have experience with coupling bending magnet radiation into a fiber? Which coupler to use, how to focus, which fiber, which frequency (range)?
I appreciate any suggestions.
Thanks,
Johannes
#47
Need help? / Re: Microscope for X-ray imagi...
Last post by LorraineBobb - September 15, 2021, 05:30:43 PMHi Cigdem,
I've used a reflective microscope with 25um LuAg in the pinhole camera, but beamsizes would be approx. (sigma_x, sigma_y) =(15um, 45um), 300mA beam, peak energy 25keV.
PERFORMANCE OF A REFLECTIVE MICROSCOPE OBJECTIVE IN AN X-RAY PINHOLE CAMERA, IBIC2018
A few thoughts:
Have you measured the MTF or PSF of the scintillator using a knife-edge? Beamlines tend to have decent targets for this.
Also have you verified the PSF from the optical system (microscope)? Just to sanity check how much PSF comes from the optics?
If you think it's an energy density issue on the scintillator, have you tried attenuating the X-ray beam or using low beam current?
Good luck! ;-)
L.
I've used a reflective microscope with 25um LuAg in the pinhole camera, but beamsizes would be approx. (sigma_x, sigma_y) =(15um, 45um), 300mA beam, peak energy 25keV.
PERFORMANCE OF A REFLECTIVE MICROSCOPE OBJECTIVE IN AN X-RAY PINHOLE CAMERA, IBIC2018
A few thoughts:
Have you measured the MTF or PSF of the scintillator using a knife-edge? Beamlines tend to have decent targets for this.
Also have you verified the PSF from the optical system (microscope)? Just to sanity check how much PSF comes from the optics?
If you think it's an energy density issue on the scintillator, have you tried attenuating the X-ray beam or using low beam current?
Good luck! ;-)
L.
#48
General Discussion / Re: BPM system in different in...
Last post by LorraineBobb - September 15, 2021, 05:11:18 PMDiamond Light Source
BPM System: 172 BPMs on storage ring (168 orginally); Libera Brilliance and Libera Electron
References: Performance of the FOFB with DDBA in Diamond Light Source, IPAC2017, TUPIK113
Diamond Light Source Electron Beam Position Feedback: Design, Realization and Performance, ICALEPCS2009, THB003
Comments:
For D-II, number of BPMs on storage ring increases to 252 and we intend to use pilot tone with analog front end in-tunnel and digital signal processing using mTCA platform in the Control and Instrumentation Areas [Diamond-II CDR ].
BPM System: 172 BPMs on storage ring (168 orginally); Libera Brilliance and Libera Electron
References: Performance of the FOFB with DDBA in Diamond Light Source, IPAC2017, TUPIK113
Diamond Light Source Electron Beam Position Feedback: Design, Realization and Performance, ICALEPCS2009, THB003
Comments:
For D-II, number of BPMs on storage ring increases to 252 and we intend to use pilot tone with analog front end in-tunnel and digital signal processing using mTCA platform in the Control and Instrumentation Areas [Diamond-II CDR ].
#49
Announcements / Job: (Senior) Diagnostics Phys...
Last post by LorraineBobb - September 13, 2021, 03:12:20 PMDear all,
I hope you are all keeping well and will have a fruitful IBIC'2021!
I'd like to let you know of the following position at Diamond Light Source, UK:
https://vacancies.diamond.ac.uk/vacancy/senior-diagnostics-physicist-engineer-448352.html
This role will define, design and deploy state-of-the-art custom RF instrumentation for world leading beam diagnostics. A key element of the role is the delivery of new diagnostics instrumentation for the future accelerator upgrade Diamond-II featuring RF design and characterisation, electronics design including PCB layouts, and developing prototypes to ensure suitability for production at scale.
Duties also include the maintenance, research and development of existing diagnostics instrumentation and feedback systems. Within this role, candidates will apply knowledge and do hands-on practical work in the lab, on the accelerator and beamlines.
Please feel free to share and apply.
Best regards,
Lorraine
Head of Diagnostics
I hope you are all keeping well and will have a fruitful IBIC'2021!
I'd like to let you know of the following position at Diamond Light Source, UK:
https://vacancies.diamond.ac.uk/vacancy/senior-diagnostics-physicist-engineer-448352.html
This role will define, design and deploy state-of-the-art custom RF instrumentation for world leading beam diagnostics. A key element of the role is the delivery of new diagnostics instrumentation for the future accelerator upgrade Diamond-II featuring RF design and characterisation, electronics design including PCB layouts, and developing prototypes to ensure suitability for production at scale.
Duties also include the maintenance, research and development of existing diagnostics instrumentation and feedback systems. Within this role, candidates will apply knowledge and do hands-on practical work in the lab, on the accelerator and beamlines.
Please feel free to share and apply.
Best regards,
Lorraine
Head of Diagnostics
#50
Need help? / Re: Microscope for X-ray imagi...
Last post by cozkan - September 13, 2021, 11:34:01 AMHi Friederike,
We didnt have any other way of checking the spot size but knowing the optics well, and having scanned the beam size we know where it stops measuring.
The depth of field of the imaging setup is sufficient and not smaller than the scintillator thickness.
I have considered the influence of the substrate (and literature informs me it is possible) but dont have the substrate separately to test, nor do I have the scintillator on a glass substrate.
Having spoken to Crytur, we think the scintillator is the bottleneck. Have decided to build an x-ray microscope and relax the imaging requirements, instead. Will test the x-ray micropscope hopefully this year.
Thanks for taking the time to respond.
Cheers,
Cigdem
We didnt have any other way of checking the spot size but knowing the optics well, and having scanned the beam size we know where it stops measuring.
The depth of field of the imaging setup is sufficient and not smaller than the scintillator thickness.
I have considered the influence of the substrate (and literature informs me it is possible) but dont have the substrate separately to test, nor do I have the scintillator on a glass substrate.
Having spoken to Crytur, we think the scintillator is the bottleneck. Have decided to build an x-ray microscope and relax the imaging requirements, instead. Will test the x-ray micropscope hopefully this year.
Thanks for taking the time to respond.
Cheers,
Cigdem