From richard.t.jones at uconn.edu Thu Oct 9 14:20:25 2025 From: richard.t.jones at uconn.edu (Richard T. Jones) Date: Thu, 9 Oct 2025 14:20:25 -0400 Subject: [Halld-tagger] [EXTERNAL] notes from tagger working group meeting this morning Message-ID: Hello all, We had a special meeting this morning at 10:00 devoted to a review of everything we know regarding the degrading response of the tagger microscope over the last few run periods. A new logbook entry has been added containing a historical record of the photon yield and other calibration constants for the TAGM which presents clear evidence of significant loss of scintillation photon yields over the past 5 years, with most of the loss occurring in the rows that saw the greatest flux of electrons. - gain and photon yield history of the tagger microscope Ideas to further investigate the exact reasons for the decrease, as well as ideas for recovering and sustaining good performance during Phase 3 running are still in process, with follow-up to happen in the next Photon Beam working group mtg next week. -Richard Jones -------------- next part -------------- An HTML attachment was scrubbed... URL: From jrsteven at jlab.org Fri Oct 10 08:36:24 2025 From: jrsteven at jlab.org (Justin Stevens) Date: Fri, 10 Oct 2025 12:36:24 +0000 Subject: [Halld-tagger] [EXTERNAL] notes from tagger working group meeting this morning In-Reply-To: References: Message-ID: <0840C242-5EDD-4244-8875-74F803C24016@jlab.org> Hi Richard, All, Thanks for the summary of yesterday?s discussion and sorry I had to leave a bit early for the DNP practice talks. While we continue to investigate the exact reason for the loss of light yield, I suggest we begin planning a test that can be performed in 2026 to evaluate the options for potential replacement of the scintillating fibers before GlueX-III. One possibility would be a small test setup on one of the PS arms with candidates for the 2x2 mm scintillators that can be tested with real signals from energy-tagged electrons. We would need an equivalent readout to the existing TAGM bundles, but most of the electronics infrastructure: f250 and f1TDC boards, crates, LV, etc. should already be available in that area for the PS/ST/TPOL readout. So, I believe we would need the TAGM preamp boards with SiPMs and light guide fibers to couple to the candidate scintillators we want to evaluate. Do we have spares of those items that could be used for such a test starting in early 2026? There is also the potentially more important question of what are the options for replacement scintillators with the appropriate shape that may be more radiation resistant and how can we test that radiation hardness? I understood from Malte that there may be some LYSO crystals with an appropriate profile and Eljen https://eljentechnology.com/products/fibers may have some appropriate fibers, but we should consider procuring these and other options soon if we aim to test them next year. More thoughts, suggestions, corrections are welcome. I just think we need to keep brainstorming on this to keep up the momentum towards finding a solution for GlueX-III. -Justin On Oct 9, 2025, at 2:20?PM, Richard T. Jones via Halld-tagger wrote: Hello all, We had a special meeting this morning at 10:00 devoted to a review of everything we know regarding the degrading response of the tagger microscope over the last few run periods. A new logbook entry has been added containing a historical record of the photon yield and other calibration constants for the TAGM which presents clear evidence of significant loss of scintillation photon yields over the past 5 years, with most of the loss occurring in the rows that saw the greatest flux of electrons. * gain and photon yield history of the tagger microscope Ideas to further investigate the exact reasons for the decrease, as well as ideas for recovering and sustaining good performance during Phase 3 running are still in process, with follow-up to happen in the next Photon Beam working group mtg next week. -Richard Jones _______________________________________________ Halld-tagger mailing list Halld-tagger at jlab.org https://mailman.jlab.org/mailman/listinfo/halld-tagger -------------- next part -------------- An HTML attachment was scrubbed... URL: From zihlmann at jlab.org Fri Oct 10 10:15:14 2025 From: zihlmann at jlab.org (zihlmann) Date: Fri, 10 Oct 2025 10:15:14 -0400 Subject: [Halld-tagger] [EXTERNAL] notes from tagger working group meeting this morning In-Reply-To: <0840C242-5EDD-4244-8875-74F803C24016@jlab.org> References: <0840C242-5EDD-4244-8875-74F803C24016@jlab.org> Message-ID: Hi All, regarding scintillator alternatives (proposed by Malte, Arshak, ...) I am investigating several paths to obtain LYSO crystals with 2mm by 2mm cross section and a length of 20mm or thereabouts. I think the length is not that important but the cross section is to fit the current geometry. I contacted two companies in the US and waiting responses. There is a company in China where one could buy online such crystals right away with a cost of 39$ per piece (excluding taxes and tarifs). So my hope is that we could get our hands on some such crystals on a rather short time scale. My basic idea is to equip the last "bundle" (most downstream), 3 columns with 5 scintillators each, with such crystals (the coupling has not yet been evaluated) till February and run with that in the next run period. If that is possible we would learn likely quite a lot about the usefulness of such crystals and hopefully a path forward to "upgrade" the full microscope. cheers, Beni On 10/10/25 08:36, Justin Stevens via Halld-tagger wrote: > Hi Richard, All, > > Thanks for the summary of yesterday?s discussion and sorry I had to > leave a bit early for the DNP practice talks. ?While we continue to > investigate the exact reason for the loss of light yield, I suggest we > begin planning a test that can be performed in 2026 to evaluate the > options for potential replacement of the scintillating fibers before > GlueX-III. > > One possibility would be a small test setup on one of the PS arms with > candidates for the 2x2 mm scintillators that can be tested with real > signals from energy-tagged electrons. ?We would need an equivalent > readout to the existing TAGM bundles, but most of the electronics > infrastructure: f250 and f1TDC boards, crates, LV, etc. should already > be available in that area for the PS/ST/TPOL readout. ?So, I believe > we would need the TAGM preamp boards with SiPMs and light guide fibers > to couple to the candidate scintillators we want to evaluate. ?Do we > have spares of those items that could be used for such a test starting > in early 2026? > > There is also the potentially more important question of what are the > options for replacement scintillators with the appropriate shape that > may be more radiation resistant and how can we test that radiation > hardness? ?I understood from Malte that there may be some LYSO > crystals with an appropriate profile and Eljen > https://eljentechnology.com/products/fibers?may have some appropriate > fibers, but we should consider procuring these and other options soon > if we aim to test them next year. > > More thoughts, suggestions, corrections are welcome. ?I just think we > need to keep brainstorming on this to keep up the momentum towards > finding a solution for GlueX-III. > > -Justin > >> On Oct 9, 2025, at 2:20?PM, Richard T. Jones via Halld-tagger >> wrote: >> >> Hello all, >> >> We had a special meeting this morning at 10:00 devoted to a review of >> everything we know regarding the degrading response of the tagger >> microscope over the last few run periods. A new logbook entry has >> been added containing a historical record of the photon yield and >> other calibration constants for the TAGM which presents clear >> evidence of significant loss of scintillation photon yields over the >> past 5 years, with most of the loss occurring in the rows that saw >> the greatest flux of electrons. >> >> * gain and photon yield history of the tagger microscope >> >> >> Ideas to further investigate the exact reasons for the decrease, as >> well as ideas for recovering and sustaining good performance during >> Phase 3 running are still in process, with follow-up to happen in the >> next Photon Beam working group mtg next week. >> >> -Richard Jones >> _______________________________________________ >> Halld-tagger mailing list >> Halld-tagger at jlab.org >> https://mailman.jlab.org/mailman/listinfo/halld-tagger > > > _______________________________________________ > Halld-tagger mailing list > Halld-tagger at jlab.org > https://mailman.jlab.org/mailman/listinfo/halld-tagger -------------- next part -------------- An HTML attachment was scrubbed... URL: From jrsteven at jlab.org Fri Oct 10 15:40:55 2025 From: jrsteven at jlab.org (Justin Stevens) Date: Fri, 10 Oct 2025 19:40:55 +0000 Subject: [Halld-tagger] [EXTERNAL] notes from tagger working group meeting this morning In-Reply-To: References: <0840C242-5EDD-4244-8875-74F803C24016@jlab.org> Message-ID: <187540C8-B42F-43CF-9287-CF98C440E1A3@jlab.org> Hi Beni, All, Thanks for the information about the crystals. I like the idea to replace some of the scintillators directly in the ?production? microscope for the experiment if we?re convinced it will produce usable signals so that we don?t create a loss of acceptance in some region of the tagger. We would learn more about the radiation hardness there than we would in the PS area. A test setup in the PS area would have the advantage that it could be more flexible to evaluate different couplings procedures or other scintillator options which are more speculative, with easier access to adjust the geometry or setup without moving the full microscope. If we have any spare material from the original scintillator from Saint-Gobain, we could also have a control sample to compare with (before radiation). Maybe we want to do both of these tests in 2026? -Justin On Oct 10, 2025, at 10:15?AM, zihlmann via Halld-tagger wrote: Hi All, regarding scintillator alternatives (proposed by Malte, Arshak, ...) I am investigating several paths to obtain LYSO crystals with 2mm by 2mm cross section and a length of 20mm or thereabouts. I think the length is not that important but the cross section is to fit the current geometry. I contacted two companies in the US and waiting responses. There is a company in China where one could buy online such crystals right away with a cost of 39$ per piece (excluding taxes and tarifs). So my hope is that we could get our hands on some such crystals on a rather short time scale. My basic idea is to equip the last "bundle" (most downstream), 3 columns with 5 scintillators each, with such crystals (the coupling has not yet been evaluated) till February and run with that in the next run period. If that is possible we would learn likely quite a lot about the usefulness of such crystals and hopefully a path forward to "upgrade" the full microscope. cheers, Beni On 10/10/25 08:36, Justin Stevens via Halld-tagger wrote: Hi Richard, All, Thanks for the summary of yesterday?s discussion and sorry I had to leave a bit early for the DNP practice talks. While we continue to investigate the exact reason for the loss of light yield, I suggest we begin planning a test that can be performed in 2026 to evaluate the options for potential replacement of the scintillating fibers before GlueX-III. One possibility would be a small test setup on one of the PS arms with candidates for the 2x2 mm scintillators that can be tested with real signals from energy-tagged electrons. We would need an equivalent readout to the existing TAGM bundles, but most of the electronics infrastructure: f250 and f1TDC boards, crates, LV, etc. should already be available in that area for the PS/ST/TPOL readout. So, I believe we would need the TAGM preamp boards with SiPMs and light guide fibers to couple to the candidate scintillators we want to evaluate. Do we have spares of those items that could be used for such a test starting in early 2026? There is also the potentially more important question of what are the options for replacement scintillators with the appropriate shape that may be more radiation resistant and how can we test that radiation hardness? I understood from Malte that there may be some LYSO crystals with an appropriate profile and Eljen https://eljentechnology.com/products/fibers may have some appropriate fibers, but we should consider procuring these and other options soon if we aim to test them next year. More thoughts, suggestions, corrections are welcome. I just think we need to keep brainstorming on this to keep up the momentum towards finding a solution for GlueX-III. -Justin On Oct 9, 2025, at 2:20?PM, Richard T. Jones via Halld-tagger

wrote: Hello all, We had a special meeting this morning at 10:00 devoted to a review of everything we know regarding the degrading response of the tagger microscope over the last few run periods. A new logbook entry has been added containing a historical record of the photon yield and other calibration constants for the TAGM which presents clear evidence of significant loss of scintillation photon yields over the past 5 years, with most of the loss occurring in the rows that saw the greatest flux of electrons. * gain and photon yield history of the tagger microscope Ideas to further investigate the exact reasons for the decrease, as well as ideas for recovering and sustaining good performance during Phase 3 running are still in process, with follow-up to happen in the next Photon Beam working group mtg next week. -Richard Jones _______________________________________________ Halld-tagger mailing list Halld-tagger at jlab.org https://mailman.jlab.org/mailman/listinfo/halld-tagger _______________________________________________ Halld-tagger mailing list Halld-tagger at jlab.org https://mailman.jlab.org/mailman/listinfo/halld-tagger _______________________________________________ Halld-tagger mailing list Halld-tagger at jlab.org https://mailman.jlab.org/mailman/listinfo/halld-tagger -------------- next part -------------- An HTML attachment was scrubbed... URL: From zihlmann at jlab.org Fri Oct 10 16:42:48 2025 From: zihlmann at jlab.org (zihlmann) Date: Fri, 10 Oct 2025 16:42:48 -0400 Subject: [Halld-tagger] [EXTERNAL] notes from tagger working group meeting this morning In-Reply-To: <187540C8-B42F-43CF-9287-CF98C440E1A3@jlab.org> References: <0840C242-5EDD-4244-8875-74F803C24016@jlab.org> <187540C8-B42F-43CF-9287-CF98C440E1A3@jlab.org> Message-ID: <9ef6c666-cf2e-4e41-9981-879539cedcd2@jlab.org> Hi Justin, and All, yes a "two path" approach may give us the most value. The LYSO may not be the best solution either. The advantage is that the geometry is very well defined like the cross section of 2mm by 2mm has a very high accuracy of 0.02mm the potential disadvantages, as pointed out by Eugene, is the potential shower effects as the radiation length of this material is 1.1cm so a 10mm long crystal may be a better choice. Secondly the signal decay time of order 35ns which may be too long at the high rates we can expect in GlueX III. cheers, Beni On 10/10/25 15:40, Justin Stevens wrote: > Hi Beni, All, > > Thanks for the information about the crystals. ?I like the idea to > replace some of the scintillators directly in the ?production? > microscope for the experiment if we?re convinced it will produce > usable signals so that we don?t create a loss of acceptance in some > region of the tagger. ?We would learn more about the radiation > hardness there than we would in the PS area. > > A test setup in the PS area would have the advantage that it could be > more flexible to evaluate different couplings procedures or other > scintillator options which are more speculative, with easier access to > adjust the geometry or setup without moving the full microscope. ?If > we have any spare material from the original scintillator from > Saint-Gobain, we could also have a control sample to compare with > (before radiation). > > Maybe we want to do both of these tests in 2026? > > -Justin > >> On Oct 10, 2025, at 10:15?AM, zihlmann via Halld-tagger >> wrote: >> >> Hi All, >> >> regarding scintillator alternatives (proposed by Malte, Arshak, ...) >> I am investigating several paths to obtain LYSO crystals >> with 2mm by 2mm cross section and a length of 20mm or thereabouts. I >> think the length is not that important but the cross section >> is to fit the current geometry. I contacted two companies in the US >> and waiting responses. There is a company in China where one >> could buy online such crystals right away with a cost of 39$ per >> piece (excluding taxes and tarifs). So my hope is that we could >> get our hands on some such crystals on a rather short time scale. >> >> My basic idea is to equip the last "bundle" (most downstream), 3 >> columns with 5 scintillators each, with such crystals >> (the coupling has not yet been evaluated) till February and run with >> that in the next run period. If that is possible we would learn >> likely quite a lot about the usefulness of such crystals and >> hopefully a path forward to "upgrade" the full microscope. >> >> cheers, >> Beni >> >> On 10/10/25 08:36, Justin Stevens via Halld-tagger wrote: >>> Hi Richard, All, >>> >>> Thanks for the summary of yesterday?s discussion and sorry I had to >>> leave a bit early for the DNP practice talks. ?While we continue to >>> investigate the exact reason for the loss of light yield, I suggest >>> we begin planning a test that can be performed in 2026 to evaluate >>> the options for potential replacement of the scintillating fibers >>> before GlueX-III. >>> >>> One possibility would be a small test setup on one of the PS arms >>> with candidates for the 2x2 mm scintillators that can be tested with >>> real signals from energy-tagged electrons. ?We would need an >>> equivalent readout to the existing TAGM bundles, but most of the >>> electronics infrastructure: f250 and f1TDC boards, crates, LV, etc. >>> should already be available in that area for the PS/ST/TPOL readout. >>> ?So, I believe we would need the TAGM preamp boards with SiPMs and >>> light guide fibers to couple to the candidate scintillators we want >>> to evaluate. ?Do we have spares of those items that could be used >>> for such a test starting in early 2026? >>> >>> There is also the potentially more important question of what are >>> the options for replacement scintillators with the appropriate shape >>> that may be more radiation resistant and how can we test that >>> radiation hardness? ?I understood from Malte that there may be some >>> LYSO crystals with an appropriate profile and Eljen >>> https://eljentechnology.com/products/fibers?may have some >>> appropriate fibers, but we should consider procuring these and other >>> options soon if we aim to test them next year. >>> >>> More thoughts, suggestions, corrections are welcome. ?I just think >>> we need to keep brainstorming on this to keep up the momentum >>> towards finding a solution for GlueX-III. >>> >>> -Justin >>> >>>> On Oct 9, 2025, at 2:20?PM, Richard T. Jones via Halld-tagger >>>> wrote: >>>> >>>> Hello all, >>>> >>>> We had a special meeting this morning at 10:00 devoted to a review >>>> of everything we know regarding the degrading response of the >>>> tagger microscope over the last few run periods. A new logbook >>>> entry has been added containing a historical record of the photon >>>> yield and other calibration constants for the TAGM which presents >>>> clear evidence of significant loss of scintillation photon yields >>>> over the past 5 years, with most of the loss occurring in the rows >>>> that saw the greatest flux of electrons. >>>> >>>> * gain and photon yield history of the tagger microscope >>>> >>>> >>>> Ideas to further investigate the exact reasons for the decrease, as >>>> well as ideas for recovering and sustaining good performance during >>>> Phase 3 running are still in process, with follow-up to happen in >>>> the next Photon Beam working group mtg next week. >>>> >>>> -Richard Jones >>>> _______________________________________________ >>>> Halld-tagger mailing list >>>> Halld-tagger at jlab.org >>>> https://mailman.jlab.org/mailman/listinfo/halld-tagger >>> >>> >>> _______________________________________________ >>> Halld-tagger mailing list >>> Halld-tagger at jlab.org >>> https://mailman.jlab.org/mailman/listinfo/halld-tagger >> >> _______________________________________________ >> Halld-tagger mailing list >> Halld-tagger at jlab.org >> https://mailman.jlab.org/mailman/listinfo/halld-tagger > -------------- next part -------------- An HTML attachment was scrubbed... URL: From malte at jlab.org Sat Oct 11 13:12:29 2025 From: malte at jlab.org (Malte Albrecht) Date: Sat, 11 Oct 2025 17:12:29 +0000 Subject: [Halld-tagger] [EXTERNAL] notes from tagger working group meeting this morning In-Reply-To: <9ef6c666-cf2e-4e41-9981-879539cedcd2@jlab.org> References: <0840C242-5EDD-4244-8875-74F803C24016@jlab.org> <187540C8-B42F-43CF-9287-CF98C440E1A3@jlab.org> <9ef6c666-cf2e-4e41-9981-879539cedcd2@jlab.org> Message-ID: Hi Beni, all, I remembered that Luxium Solutions (formerly Saint Gobin Crystals) produces custom arrays (1D or 2D) of small scintillation crystals for various applications. The whole development is driven by the medical industry, but it was investigated for LHC detectors as well. If the material proves to be useful for us, one could imagine ordering pre-fabricated linear arrays instead of individual little crystals. Here is some more info: https://luxiumsolutions.com/radiation-detector-assemblies/pixellated-arrays I also looked for the radiation hardness: For larger LYSO(Ce) crystals, a test at Caltech for SLHC showed a loss of light yield of about 10% at 1MRad (see http://www.its.caltech.edu/~rzhu/talks/marat_091029_slhc.pdf ) Of course the decay time of the pulse is crucial for us. I checked Alex Barnes dissertation - the current scintillators have a decay time of 2.7ns, so the LYSO would be about a factor 10 worse. That means, at high rates we will have pile-up, that may or may not be recoverable. Another option I came across: Apparently there is a more radiation-hard variant of the scintillating fibers we are using now. Luxium advertises the ones we have now (BCF-20) as well as a slightly slower (7ns decay time), but more radiation hard variant called BCF-60XL. Probably these are not available in a square cross section, but nevertheless worth investigating: https://luxiumsolutions.com/radiation-detection-scintillators/fibers Best, Malte > On Oct 10, 2025, at 4:42?PM, zihlmann via Halld-tagger wrote: > > Hi Justin, and All, > > yes a "two path" approach may give us the most value. > The LYSO may not be the best solution either. The advantage is that the geometry is very well defined > like the cross section of 2mm by 2mm has a very high accuracy of 0.02mm the potential disadvantages, > as pointed out by Eugene, is the potential shower effects as the radiation length of this material is 1.1cm > so a 10mm long crystal may be a better choice. Secondly the signal decay time of order 35ns which may > be too long at the high rates we can expect in GlueX III. > > cheers, > Beni > > > > On 10/10/25 15:40, Justin Stevens wrote: >> Hi Beni, All, >> >> Thanks for the information about the crystals. I like the idea to replace some of the scintillators directly in the ?production? microscope for the experiment if we?re convinced it will produce usable signals so that we don?t create a loss of acceptance in some region of the tagger. We would learn more about the radiation hardness there than we would in the PS area. >> >> A test setup in the PS area would have the advantage that it could be more flexible to evaluate different couplings procedures or other scintillator options which are more speculative, with easier access to adjust the geometry or setup without moving the full microscope. If we have any spare material from the original scintillator from Saint-Gobain, we could also have a control sample to compare with (before radiation). >> >> Maybe we want to do both of these tests in 2026? >> >> -Justin >> >>> On Oct 10, 2025, at 10:15?AM, zihlmann via Halld-tagger wrote: >>> >>> Hi All, >>> >>> regarding scintillator alternatives (proposed by Malte, Arshak, ...) I am investigating several paths to obtain LYSO crystals >>> with 2mm by 2mm cross section and a length of 20mm or thereabouts. I think the length is not that important but the cross section >>> is to fit the current geometry. I contacted two companies in the US and waiting responses. There is a company in China where one >>> could buy online such crystals right away with a cost of 39$ per piece (excluding taxes and tarifs). So my hope is that we could >>> get our hands on some such crystals on a rather short time scale. >>> >>> My basic idea is to equip the last "bundle" (most downstream), 3 columns with 5 scintillators each, with such crystals >>> (the coupling has not yet been evaluated) till February and run with that in the next run period. If that is possible we would learn >>> likely quite a lot about the usefulness of such crystals and hopefully a path forward to "upgrade" the full microscope. >>> >>> cheers, >>> Beni >>> >>> On 10/10/25 08:36, Justin Stevens via Halld-tagger wrote: >>>> Hi Richard, All, >>>> >>>> Thanks for the summary of yesterday?s discussion and sorry I had to leave a bit early for the DNP practice talks. While we continue to investigate the exact reason for the loss of light yield, I suggest we begin planning a test that can be performed in 2026 to evaluate the options for potential replacement of the scintillating fibers before GlueX-III. >>>> >>>> One possibility would be a small test setup on one of the PS arms with candidates for the 2x2 mm scintillators that can be tested with real signals from energy-tagged electrons. We would need an equivalent readout to the existing TAGM bundles, but most of the electronics infrastructure: f250 and f1TDC boards, crates, LV, etc. should already be available in that area for the PS/ST/TPOL readout. So, I believe we would need the TAGM preamp boards with SiPMs and light guide fibers to couple to the candidate scintillators we want to evaluate. Do we have spares of those items that could be used for such a test starting in early 2026? >>>> >>>> There is also the potentially more important question of what are the options for replacement scintillators with the appropriate shape that may be more radiation resistant and how can we test that radiation hardness? I understood from Malte that there may be some LYSO crystals with an appropriate profile and Eljen https://eljentechnology.com/products/fibers may have some appropriate fibers, but we should consider procuring these and other options soon if we aim to test them next year. >>>> >>>> More thoughts, suggestions, corrections are welcome. I just think we need to keep brainstorming on this to keep up the momentum towards finding a solution for GlueX-III. >>>> >>>> -Justin >>>> >>>>> On Oct 9, 2025, at 2:20?PM, Richard T. Jones via Halld-tagger wrote: >>>>> >>>>> Hello all, >>>>> >>>>> We had a special meeting this morning at 10:00 devoted to a review of everything we know regarding the degrading response of the tagger microscope over the last few run periods. A new logbook entry has been added containing a historical record of the photon yield and other calibration constants for the TAGM which presents clear evidence of significant loss of scintillation photon yields over the past 5 years, with most of the loss occurring in the rows that saw the greatest flux of electrons. >>>>> ? gain and photon yield history of the tagger microscope >>>>> Ideas to further investigate the exact reasons for the decrease, as well as ideas for recovering and sustaining good performance during Phase 3 running are still in process, with follow-up to happen in the next Photon Beam working group mtg next week. >>>>> >>>>> -Richard Jones >>>>> _______________________________________________ >>>>> Halld-tagger mailing list >>>>> Halld-tagger at jlab.org >>>>> https://mailman.jlab.org/mailman/listinfo/halld-tagger >>>> >>>> >>>> _______________________________________________ >>>> Halld-tagger mailing list >>>> Halld-tagger at jlab.org >>>> https://mailman.jlab.org/mailman/listinfo/halld-tagger >>>> >>> >>> _______________________________________________ >>> Halld-tagger mailing list >>> Halld-tagger at jlab.org >>> https://mailman.jlab.org/mailman/listinfo/halld-tagger >> > > _______________________________________________ > Halld-tagger mailing list > Halld-tagger at jlab.org > https://mailman.jlab.org/mailman/listinfo/halld-tagger From jrsteven at jlab.org Thu Oct 16 09:16:48 2025 From: jrsteven at jlab.org (Justin Stevens) Date: Thu, 16 Oct 2025 13:16:48 +0000 Subject: [Halld-tagger] Beamline meeting today at 10 am Message-ID: Hi All, We will have a beamline meeting this morning at 10 am to continue our discussion of the tagger microscope status and plans. A wiki page can be found at https://halldweb.jlab.org/wiki/index.php/BLTWG_Meeting_10/16/2025 and we?ll meet in F326 for those at JLab. -Justin -------------- next part -------------- An HTML attachment was scrubbed... URL: From zihlmann at jlab.org Thu Oct 16 16:06:04 2025 From: zihlmann at jlab.org (zihlmann) Date: Thu, 16 Oct 2025 16:06:04 -0400 Subject: [Halld-tagger] microscope pictures with green / blue laser Message-ID: <10d3450f-e860-4ee2-9926-685c3c417ee2@jlab.org> Hi All, I added several more pictures and "movies" to the photo album of the tagger microscope: https://photos.app.goo.gl/Q9To4SutT7854mmV6 I highlighted a few points with three picked out pictures (see attached pdf file) With the green laser shining into the front face of the scintillator one can nicely see where the "losses" are in the fiber front face, in the fused section and along the light guide. In addition, I looked at the timing resolution of the pair spectrometer tiles and I find in my quick and dirty approach very similar timing resolutions as for tagger microscope of order 300ps. cheers, Beni -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: tagger_microscope_laser_light_input.pdf Type: application/pdf Size: 208719 bytes Desc: not available URL: From hovanes.egiyan at gmail.com Thu Oct 16 19:02:19 2025 From: hovanes.egiyan at gmail.com (Hovanes Egiyan) Date: Thu, 16 Oct 2025 19:02:19 -0400 Subject: [Halld-tagger] [EXTERNAL] Re: microscope pictures with green / blue laser In-Reply-To: <10d3450f-e860-4ee2-9926-685c3c417ee2@jlab.org> References: <10d3450f-e860-4ee2-9926-685c3c417ee2@jlab.org> Message-ID: Hi Beni, Thanks for the nice pictures. GlueX NIM paper quotes 230ps for the timing resolution for TAGM. Best, Hovanes. On Thu, Oct 16, 2025 at 4:06?PM zihlmann via Halld-tagger < halld-tagger at jlab.org> wrote: > > Hi All, > > I added several more pictures and "movies" to the photo album of the > tagger microscope: > https://urldefense.proofpoint.com/v2/url?u=https-3A__photos.app.goo.gl_Q9To4SutT7854mmV6&d=DwIFaQ&c=CJqEzB1piLOyyvZjb8YUQw&r=-MwMW0sKroUIjy-Lh9rb3KzmWIgdcbbr9_jez8RLmto&m=NkMwwaoaUBgWwxZsMl8bZrVpWI2--3cseCUiSRuvp3jemr2BhLhci6l_yqd8WeTT&s=9kD-iPlHU_3sreIlCIgihFRcXV3-Cc4uIV0ibXDjLvw&e= > I highlighted a few points with three picked out pictures (see attached > pdf file) > With the green laser shining into the front face of the scintillator one > can nicely see > where the "losses" are in the fiber front face, in the fused section and > along the light guide. > > In addition, I looked at the timing resolution of the pair spectrometer > tiles and I find in > my quick and dirty approach very similar timing resolutions as for tagger > microscope > of order 300ps. > > cheers, > Beni > > > > > _______________________________________________ > Halld-tagger mailing list > Halld-tagger at jlab.org > https://mailman.jlab.org/mailman/listinfo/halld-tagger > -------------- next part -------------- An HTML attachment was scrubbed... URL: From zihlmann at jlab.org Fri Oct 17 06:47:59 2025 From: zihlmann at jlab.org (zihlmann) Date: Fri, 17 Oct 2025 06:47:59 -0400 Subject: [Halld-tagger] [EXTERNAL] Re: microscope pictures with green / blue laser In-Reply-To: References: <10d3450f-e860-4ee2-9926-685c3c417ee2@jlab.org> Message-ID: Hi Hovanes, with my naive plugin looking at tagger time minus RF time I see a sigma of about 400ps. nothing sophisticated to optimize the result. I see similar sigmas for the PS tiles times where I use the PS coarse counters as time reference. Also, the PS tiles do not have TDCs only fADCs. cheers, Beni On 10/16/25 19:02, Hovanes Egiyan wrote: > Hi Beni, > > Thanks for the nice pictures. > > GlueX NIM paper quotes 230ps for the timing resolution for TAGM. > > Best, > ? ? Hovanes. > > On Thu, Oct 16, 2025 at 4:06?PM zihlmann via Halld-tagger > wrote: > > > Hi All, > > I added several more pictures and "movies" to the photo album of > the tagger microscope: > https://photos.app.goo.gl/Q9To4SutT7854mmV6 > I highlighted a few points with three picked out pictures (see > attached pdf file) > With the green laser shining into the front face of the > scintillator one can nicely see > where the "losses" are in the fiber front face, in the fused > section and along the light guide. > > In addition, I looked at the timing resolution of the pair > spectrometer tiles and I find in > my quick and dirty approach very similar timing resolutions as for > tagger microscope > of order 300ps. > > cheers, > Beni > > > > > _______________________________________________ > Halld-tagger mailing list > Halld-tagger at jlab.org > https://mailman.jlab.org/mailman/listinfo/halld-tagger > -------------- next part -------------- An HTML attachment was scrubbed... URL: From richard.t.jones at uconn.edu Fri Oct 17 07:31:23 2025 From: richard.t.jones at uconn.edu (Richard T. Jones) Date: Fri, 17 Oct 2025 07:31:23 -0400 Subject: [Halld-tagger] [EXTERNAL] Re: microscope pictures with green / blue laser In-Reply-To: References: <10d3450f-e860-4ee2-9926-685c3c417ee2@jlab.org>

Message-ID: Beni, Yes we are around 400ps rms in the TAGM now, but as Hovanes says it was closer to 200ps when the device was first installed. This shows the degree to which its light output has now degraded. But I think the PS coarse counters were always at this same level of 400-500ps. -Richard J. On Fri, Oct 17, 2025 at 6:48?AM zihlmann via Halld-tagger < halld-tagger at jlab.org> wrote: > *External sender: This message was not sent through the UConn email > system. It might be safe, but use caution before interacting with links, > attachments, or requests.* > > Hi Hovanes, > with my naive plugin looking at tagger time minus RF time I see a sigma of > about 400ps. > nothing sophisticated to optimize the result. > I see similar sigmas for the PS tiles times where I use the PS coarse > counters as time reference. > Also, the PS tiles do not have TDCs only fADCs. > > cheers, > Beni > > On 10/16/25 19:02, Hovanes Egiyan wrote: > > Hi Beni, > > Thanks for the nice pictures. > > GlueX NIM paper quotes 230ps for the timing resolution for TAGM. > > Best, > Hovanes. > > On Thu, Oct 16, 2025 at 4:06?PM zihlmann via Halld-tagger < > halld-tagger at jlab.org> wrote: > >> >> Hi All, >> >> I added several more pictures and "movies" to the photo album of the >> tagger microscope: >> https://urldefense.proofpoint.com/v2/url?u=https-3A__photos.app.goo.gl_Q9To4SutT7854mmV6&d=DwIFaQ&c=CJqEzB1piLOyyvZjb8YUQw&r=-MwMW0sKroUIjy-Lh9rb3KzmWIgdcbbr9_jez8RLmto&m=rMwvMqK1euAEfP4G46eSIxNr-_ndnPU3anhIfXpXO7yFanAXvm2vQvJ_QGDecThf&s=-gRLmp9sUJvio8g1xpR8DiIQQtFhbKYRciftb9jJN-k&e= >> I highlighted a few points with three picked out pictures (see attached >> pdf file) >> With the green laser shining into the front face of the scintillator one >> can nicely see >> where the "losses" are in the fiber front face, in the fused section and >> along the light guide. >> >> In addition, I looked at the timing resolution of the pair spectrometer >> tiles and I find in >> my quick and dirty approach very similar timing resolutions as for tagger >> microscope >> of order 300ps. >> >> cheers, >> Beni >> >> >> >> >> _______________________________________________ >> Halld-tagger mailing list >> Halld-tagger at jlab.org >> https://mailman.jlab.org/mailman/listinfo/halld-tagger >> >> > > _______________________________________________ > Halld-tagger mailing list > Halld-tagger at jlab.org > https://mailman.jlab.org/mailman/listinfo/halld-tagger > -------------- next part -------------- An HTML attachment was scrubbed... URL: From richard.t.jones at uconn.edu Fri Oct 17 09:12:48 2025 From: richard.t.jones at uconn.edu (Richard T. Jones) Date: Fri, 17 Oct 2025 09:12:48 -0400 Subject: [Halld-tagger] [EXTERNAL] Re: microscope pictures with green / blue laser In-Reply-To: <316b0d03-44be-43e9-9d6e-857a18c9b0de@jlab.org> References: <10d3450f-e860-4ee2-9926-685c3c417ee2@jlab.org>

<316b0d03-44be-43e9-9d6e-857a18c9b0de@jlab.org> Message-ID: Beni and all, Granted 400ps is not great, but I think we can do a lot better using the design we talked about yesterday because: 1. we will have both a tdc and adc for timing 2. we will have 2 channels of wavelength-shifting readout per column instead of 1 3. we will also have direct blue light with much faster rise time on readout rows 2-4, albeit with lower photon statistics In summing mode all 5 channels will be summed in analog to form the pulse, but the blue light should increase the rise time of the leading edge assuming any of this light reaches the SiPMs. -Richard On Fri, Oct 17, 2025 at 8:30?AM zihlmann wrote: > *External sender: This message was not sent through the UConn email > system. It might be safe, but use caution before interacting with links, > attachments, or requests.* > > Hi Richard, > you can make your own conclusions by looking at the two attached root > files. > TAGGER1_ps_test.root for the tagger microscope histogram 2d tagmTmRF > and project any x-channel to the vertical axis and fit the prompt peak. > even > for the good columns the resolution is not better than 400ps. > hdroot_PS_run133180 take 2d histogram psDTpsc and project any x-channel > to the vertical axis you get better than 400ps. And remember, the ps tiles > do not have TDCs, the time comes only from the fADCs. > > cheers, > Beni > > On 10/17/25 07:31, Richard T. Jones wrote: > > Beni, > > Yes we are around 400ps rms in the TAGM now, but as Hovanes says it was > closer to 200ps when the device was first installed. This shows the degree > to which its light output has now degraded. But I think the PS coarse > counters were always at this same level of 400-500ps. > > -Richard J. > > > On Fri, Oct 17, 2025 at 6:48?AM zihlmann via Halld-tagger < > halld-tagger at jlab.org> wrote: > >> *External sender: This message was not sent through the UConn email >> system. It might be safe, but use caution before interacting with links, >> attachments, or requests.* >> >> Hi Hovanes, >> with my naive plugin looking at tagger time minus RF time I see a sigma >> of about 400ps. >> nothing sophisticated to optimize the result. >> I see similar sigmas for the PS tiles times where I use the PS coarse >> counters as time reference. >> Also, the PS tiles do not have TDCs only fADCs. >> >> cheers, >> Beni >> >> On 10/16/25 19:02, Hovanes Egiyan wrote: >> >> Hi Beni, >> >> Thanks for the nice pictures. >> >> GlueX NIM paper quotes 230ps for the timing resolution for TAGM. >> >> Best, >> Hovanes. >> >> On Thu, Oct 16, 2025 at 4:06?PM zihlmann via Halld-tagger < >> halld-tagger at jlab.org> wrote: >> >>> >>> Hi All, >>> >>> I added several more pictures and "movies" to the photo album of the >>> tagger microscope: >>> https://urldefense.proofpoint.com/v2/url?u=https-3A__photos.app.goo.gl_Q9To4SutT7854mmV6&d=DwIFaQ&c=CJqEzB1piLOyyvZjb8YUQw&r=-MwMW0sKroUIjy-Lh9rb3KzmWIgdcbbr9_jez8RLmto&m=TcIvojmxs4CshyHEa8JSkCFYf8deaC455OspNOoo-F5KBB3ORgYyR_M20bQEvRIo&s=BHw0yC4CMsmJqBPShHBoS3wZr_Y4Q-UZPdx8fEQrkDE&e= >>> I highlighted a few points with three picked out pictures (see attached >>> pdf file) >>> With the green laser shining into the front face of the scintillator one >>> can nicely see >>> where the "losses" are in the fiber front face, in the fused section and >>> along the light guide. >>> >>> In addition, I looked at the timing resolution of the pair spectrometer >>> tiles and I find in >>> my quick and dirty approach very similar timing resolutions as for >>> tagger microscope >>> of order 300ps. >>> >>> cheers, >>> Beni >>> >>> >>> >>> >>> _______________________________________________ >>> Halld-tagger mailing list >>> Halld-tagger at jlab.org >>> https://mailman.jlab.org/mailman/listinfo/halld-tagger >>> >>> >> >> _______________________________________________ >> Halld-tagger mailing list >> Halld-tagger at jlab.org >> https://mailman.jlab.org/mailman/listinfo/halld-tagger >> >> > > -------------- next part -------------- An HTML attachment was scrubbed... URL: From zihlmann at jlab.org Thu Oct 23 06:48:41 2025 From: zihlmann at jlab.org (zihlmann) Date: Thu, 23 Oct 2025 06:48:41 -0400 Subject: [Halld-tagger] Beamline meeting today 10am Message-ID: <84b9b60e-e090-4395-9cbb-2f4747b85da9@jlab.org> Hi All, We will have a beamline meeting this morning at 10 am to continue our discussion of the tagger microscope status and plans and most importantly take decisions in preparation for the next run period. A wiki page can be found at https://halldweb.jlab.org/wiki/index.php/BLTWG_Meeting_10/23/2025 and we?ll meet in F326 for those at JLab. cheers, Beni From hovanes.egiyan at gmail.com Thu Oct 23 08:52:26 2025 From: hovanes.egiyan at gmail.com (Hovanes Egiyan) Date: Thu, 23 Oct 2025 08:52:26 -0400 Subject: [Halld-tagger] [EXTERNAL] Re: Beamline meeting today 10am In-Reply-To: <84b9b60e-e090-4395-9cbb-2f4747b85da9@jlab.org> References: <84b9b60e-e090-4395-9cbb-2f4747b85da9@jlab.org> Message-ID: Hi, Is it possible to adjust the time of these meetings? This new schedule of the beamline meetings conflicts with the Hall D Controls meeting which happens once a month? Hovanes. On Thu, Oct 23, 2025 at 6:49?AM zihlmann via Halld-tagger < halld-tagger at jlab.org> wrote: > Hi All, > > We will have a beamline meeting this morning at 10 am to continue our > discussion of the tagger microscope status and plans and most importantly > take decisions in preparation for the next run period. > A wiki page can be found at > https://halldweb.jlab.org/wiki/index.php/BLTWG_Meeting_10/23/2025 > and we?ll meet in F326 for those at JLab. > > > cheers, > Beni > _______________________________________________ > Halld-tagger mailing list > Halld-tagger at jlab.org > https://mailman.jlab.org/mailman/listinfo/halld-tagger > -------------- next part -------------- An HTML attachment was scrubbed... URL: From richard.t.jones at uconn.edu Thu Oct 23 11:42:42 2025 From: richard.t.jones at uconn.edu (Richard T. Jones) Date: Thu, 23 Oct 2025 11:42:42 -0400 Subject: [Halld-tagger] [EXTERNAL] Re: Beamline meeting today 10am In-Reply-To: <84b9b60e-e090-4395-9cbb-2f4747b85da9@jlab.org> References: <84b9b60e-e090-4395-9cbb-2f4747b85da9@jlab.org> Message-ID: Beni and all, I just looked back in our records, and verified that the NIM article is correct, the material we are using in the TAGM is: 1. BCF-20 green scintillator for the scintillator fibers 2. BCF-98 clear fiber for the light guides I was mistaken in my claim that we were using BCF-92 for the scintillating fibers. That makes it more mysterious to me why the fibers have shown such a marked decline in light yield with radiation dose, as compared with blue scintillator that should be more sensitive to radiation damage. I have to look further into this. -Richard On Thu, Oct 23, 2025 at 6:49?AM zihlmann via Halld-tagger < halld-tagger at jlab.org> wrote: > *External sender: This message was not sent through the UConn email > system. It might be safe, but use caution before interacting with links, > attachments, or requests.* > > > Hi All, > > We will have a beamline meeting this morning at 10 am to continue our > discussion of the tagger microscope status and plans and most importantly > take decisions in preparation for the next run period. > A wiki page can be found at > > https://urldefense.proofpoint.com/v2/url?u=https-3A__nam10.safelinks.protection.outlook.com_-3Furl-3Dhttps-253A-252F-252Fhalldweb.jlab.org-252Fwiki-252Findex.php-252FBLTWG-5FMeeting-5F10-252F23-252F2025-26data-3D05-257C02-257Crichard.t.jones-2540uconn.edu-257C3a260bd98eae4331b05e08de1221d301-257C17f1a87e2a254eaab9df9d439034b080-257C0-257C0-257C638968133658451066-257CUnknown-257CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ-253D-253D-257C0-257C-257C-257C-26sdata-3DjKt-252Fqdtd2S9eTNdvSkv0L1ItxM71-252ByuqvJl4E2GBEiY-253D-26reserved-3D0&d=DwIFaQ&c=CJqEzB1piLOyyvZjb8YUQw&r=-MwMW0sKroUIjy-Lh9rb3KzmWIgdcbbr9_jez8RLmto&m=BJtBuntB7A5xb0d04tdMIPm3r_leWN0Pj8Uczk1xpSU-f-8XYjdJ_dllf4rKMyNj&s=9Ajaswm6jicH75ihUZayqohZ_YX9FBpAXpoXr94vgjI&e= > and we?ll meet in F326 for those at JLab. > > > cheers, > Beni > _______________________________________________ > Halld-tagger mailing list > Halld-tagger at jlab.org > > https://urldefense.proofpoint.com/v2/url?u=https-3A__nam10.safelinks.protection.outlook.com_-3Furl-3Dhttps-253A-252F-252Fmailman.jlab.org-252Fmailman-252Flistinfo-252Fhalld-2Dtagger-26data-3D05-257C02-257Crichard.t.jones-2540uconn.edu-257C3a260bd98eae4331b05e08de1221d301-257C17f1a87e2a254eaab9df9d439034b080-257C0-257C0-257C638968133658473395-257CUnknown-257CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ-253D-253D-257C0-257C-257C-257C-26sdata-3DN9qvTTjks1sXzBF-252ByH4fF8-252Fr5HE3aL30zux1O6ezCiw-253D-26reserved-3D0&d=DwIFaQ&c=CJqEzB1piLOyyvZjb8YUQw&r=-MwMW0sKroUIjy-Lh9rb3KzmWIgdcbbr9_jez8RLmto&m=BJtBuntB7A5xb0d04tdMIPm3r_leWN0Pj8Uczk1xpSU-f-8XYjdJ_dllf4rKMyNj&s=jlLjE4NF8YQqG6dbCxKDutH0Hx2HtmVjW7scqE8Nk6w&e= > -------------- next part -------------- An HTML attachment was scrubbed... URL: From somov at jlab.org Thu Oct 23 11:56:43 2025 From: somov at jlab.org (Alexander Somov) Date: Thu, 23 Oct 2025 15:56:43 +0000 Subject: [Halld-tagger] [EXTERNAL] Re: Beamline meeting today 10am In-Reply-To: References: <84b9b60e-e090-4395-9cbb-2f4747b85da9@jlab.org> Message-ID: Hi, For the PS we used: BCF-92 (1 mm x 1 mm square double-clad WLS fibers) EJ - 212 scintillator tiles Cheers, Sasha ________________________________ From: Halld-tagger on behalf of Richard T. Jones via Halld-tagger Sent: Thursday, October 23, 2025 11:42 AM To: Benedikt Zihlmann Cc: halld-tagger at jlab.org Subject: [Halld-tagger] [EXTERNAL] Re: Beamline meeting today 10am Beni and all, I just looked back in our records, and verified that the NIM article is correct, the material we are using in the TAGM is: 1. BCF-20 green scintillator for the scintillator fibers 2. BCF-98 clear fiber for the light guides I was mistaken in my claim that we were using BCF-92 for the scintillating fibers. That makes it more mysterious to me why the fibers have shown such a marked decline in light yield with radiation dose, as compared with blue scintillator that should be more sensitive to radiation damage. I have to look further into this. -Richard On Thu, Oct 23, 2025 at 6:49?AM zihlmann via Halld-tagger > wrote: *External sender: This message was not sent through the UConn email system. It might be safe, but use caution before interacting with links, attachments, or requests.* Hi All, We will have a beamline meeting this morning at 10 am to continue our discussion of the tagger microscope status and plans and most importantly take decisions in preparation for the next run period. A wiki page can be found at https://nam10.safelinks.protection.outlook.com/?url=https%3A%2F%2Fhalldweb.jlab.org%2Fwiki%2Findex.php%2FBLTWG_Meeting_10%2F23%2F2025&data=05%7C02%7Crichard.t.jones%40uconn.edu%7C3a260bd98eae4331b05e08de1221d301%7C17f1a87e2a254eaab9df9d439034b080%7C0%7C0%7C638968133658451066%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=jKt%2Fqdtd2S9eTNdvSkv0L1ItxM71%2ByuqvJl4E2GBEiY%3D&reserved=0 and we?ll meet in F326 for those at JLab. cheers, Beni _______________________________________________ Halld-tagger mailing list Halld-tagger at jlab.org https://nam10.safelinks.protection.outlook.com/?url=https%3A%2F%2Fmailman.jlab.org%2Fmailman%2Flistinfo%2Fhalld-tagger&data=05%7C02%7Crichard.t.jones%40uconn.edu%7C3a260bd98eae4331b05e08de1221d301%7C17f1a87e2a254eaab9df9d439034b080%7C0%7C0%7C638968133658473395%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=N9qvTTjks1sXzBF%2ByH4fF8%2Fr5HE3aL30zux1O6ezCiw%3D&reserved=0 -------------- next part -------------- An HTML attachment was scrubbed... URL: From richard.t.jones at uconn.edu Thu Oct 23 12:17:37 2025 From: richard.t.jones at uconn.edu (Richard T. Jones) Date: Thu, 23 Oct 2025 12:17:37 -0400 Subject: [Halld-tagger] [EXTERNAL] Re: good WSF candidate In-Reply-To: <84df516a-f361-4330-aa47-a8c67cea5067@jlab.org> References: <84df516a-f361-4330-aa47-a8c67cea5067@jlab.org> Message-ID: Hello all, Here is a paper from LHCb with a passing comment at radiation damage sensitivity in BCF-20 that seems highly relevant to what we are seeing in the TAGM. Check out the following comment [p. 12], made in passing, about BCF-20 being ruled out due to radiation damage sensitivity. A significant problem with the 3HF fibre is the long decay time constant of > 7 ns. For the proposed SciFi tracker upgrade, this is a substantial > disadvantage. Including the 15 ns propagation time of the signal from the > furthest positions, it significantly complicates the task of collecting the > signal within a single bunch crossing interval. *Addition of a mirror to > the fibre end further complicates the timing of the signal. Saint-Gobain > has a fast, green (492 nm) scintillating fibre, the BCF-20, but the fluors > were found to be damaged quite easily under irradiation and cannot be > considered* It would be interesting to know more about this. The full paper is attached. -Richard On Thu, Oct 23, 2025 at 12:10?PM zihlmann wrote: > Hi Richard, > > a good WSF candidate is BCF-92XL (seems to be very similar to what is used > in PS) > https://urldefense.proofpoint.com/v2/url?u=https-3A__luxiumsolutions.com_radiation-2Ddetection-2Dscintillators_fibers&d=DwIFaQ&c=CJqEzB1piLOyyvZjb8YUQw&r=-MwMW0sKroUIjy-Lh9rb3KzmWIgdcbbr9_jez8RLmto&m=SmsWm3rOWbDNIfT4O6z0gKZvePuu2wHj_cxxOGNA2vQpZb64JmJKpyzI_7Desv5m&s=_j6qXYSa1bld8Fy72yvfZb-PWvWwApH4d5CL26DS9DY&e= > > [image: WSF parameters] > -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: wsf_parameters.png Type: image/png Size: 78255 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: LHCb-PUB-2014-015.pdf Type: application/pdf Size: 2195535 bytes Desc: not available URL: