CERN Courier October 2018 SUPERCON, Inc. Superconducting Wire and Cable Standard and Specialty designs are available to meet your most demanding Defeating the background in superconductor requirements. SUPERCON, Inc. has been producing niobium-based superconducting wires and cables for half a century. the search for dark matter We are the original SUPERCON – the world’s first commercial producer of niobium-alloy based wire and cable for superconducting applications. Y Suvorov Standard SC Wire Types Product Applications A global effort is under way to carry out a NbTi Wires Magnetic Resonance Imaging complete search for high-mass dark-matter Nb3Sn —Bronze Nuclear Magnetic Resonance Nb3Sn —Internal Tin High Energy Physics particles using an experiment called CuNi resistive matrix wires SC Magnetic Energy Storage DarkSide-20k and its successor, Fine diameter SC Wires Medical Therapeutic Devices Aluminum clad wire Superconducting Magnets and Coils which rely on novel liquid- technologies. Wire-in-Channel Crystal Growth Magnets Innovative composite wires Scientific Projects Compelling cosmological and astrophysical evidence for the existence of dark matter suggests that there is a new world beyond “We deliver superconductivity!” the Standard Model of particle physics still to be discovered and explored. Yet, despite decades of effort, direct searches for dark Contact us at [email protected] matter at particle accelerators and underground laboratories alike www.SUPERCON-WIRE.com have so far come up empty handed. This calls for new and improved methods to spot the mysterious substance thought to make up most of the matter in the universe. ad.indd 1 28/03/2012 09:43 Dark-matter searches using detectors based on liquefied noble gases such as and argon have long demonstrated great dis- Inspecting photomultiplier tubes for the DarkSide-50 detector. covery potential and continue to play a major role in the field. Such experiments use a large volume of material in which nuclei struck by to collect more than 1000 tonne × year, both potentially with no Helping you to build your next a dark-matter particle would create a tiny burst of scintillation light, instrumental background. These experiments promise the most generation control system and the very low expected event rate requires that backgrounds are complete exploration of the mass/parameter range of the present kept to a minimum. Searches employing argon detectors have a dark-matter paradigm. particular advantage because they can significantly reduce events Extended Lifespan FPGA Centric Integration Support from background sources, such as background from the abundant Direct detection with liquid argon Growing User Community Open Standards Modularity radioactive decays from detector materials and from electron scat- One well-considered form of dark matter that matches astro- tering by solar neutrinos. That will leave the low-rate nuclear recoils nomical measurements is weakly interacting massive particles VME64x and MTCA.4 Line of AMCs and µRTMs induced by coherent scattering of atmospheric neutrinos as the sole (WIMPs), which would exist in our galaxy with defined numbers IFC_1211 VME64x Intelligent FMC Carrier SBC residual background – the so-called “neutrino floor”. and velocities. In a dark-matter experiment employing a liquid- Enter the Global Argon Dark Matter Collaboration (GADMC), argon detector, such particles would collide with argon nuclei, IFC_1410 MTCA.4 Intelligent FMC Carrier AMC which was formed in September 2017. Comprising more than 300 causing them to recoil. These nuclear recoils produce ionised and IFC_1420 MTCA.4 High-Performance Digitizer AMC scientists from 15 countries and 60 institutions involved in four excited argon atoms which, after a series of reactions, form short- RSP_1461 MTCA.4 Com Extender µRTM first-generation dark-matter experiments – ArDM at Laborato- lived argon dimers (weakly bonded molecules) that decay and rio Subterráneo de Canfranc in Spain, DarkSide-50 at INFN’s emit scintillation light. The time profile of the scintillation light is Comprehensive Family of FMC Modules Laboratori Nazionali del significantly different from that created by argon-ionising events ADC_3110 8 x ADC 16-bit @ 250 Msps Gran Sasso (LNGS) in Italy, associated with radioactivity in the detector material, and has been ADC_3112 4 x ADC 12-bit @ 1 Gsps DEAP-3600 and MiniCLEAN shown to enable a strong rejection of background sources through DAC_3113 2 x DAC 16-bit Argon-based dark- at SNOLAB in Canada – a technique known as pulse-shape discrimination. GADMC is working towards Located at LNGS, DarkSide-50 is the first physics detector of ADC_3117 20 x ADC 16-bit @ 5 Msps matter searches the immediate deployment of the DarkSide programme for dark-matter detection, with a fidu- FPGA Design Kits & EPICS Integration have had a number a dark-matter detector called cial mass of 50 kg. The experiment produced its first WIMP search of successes in the DarkSide-20k. The experiment results in December 2014 using argon harvested from the atmos- would accumulate an exposure phere and, in October the following year, reported the first ever past two years. of 100 tonne × year and be fol- WIMP search results using lower-radioactivity underground argon. lowed by a much larger detector DarkSide-50 uses a detection scheme based on a dual-phase time http://www.ioxos.ch

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CCOct18_DARKSIDE_v4.indd 21 21/09/2018 13:22 CERNCOURIER www. V o l u m e 5 8 N u m b e r 8 O c t o b e r 2 0 1 8 CERN Courier October 2018 CERN Courier October 2018 Dark matter Dark matter CERN-PHOTO-201711-287-5 projection chamber (TPC), which contains a small region of gase- collab. DarkSide

ous argon above a larger region of liquid argon (figure 1, left). In this Ward M configuration, secondary scintillation light, generated by ionisation electrons that drift up through the liquid region and are accelerated into the gaseous one, are used together with the primary scintilla- tion light to look for a signal. Compared to single-phase detectors using only the pulse-shape discrimination technique, this search method requires even greater care in restricting the radioactive background through detector design and fabrication but provides excellent position resolution. For low-mass (<10 GeV/c2) WIMPs, the primary scintillation light is nearly absent, but the detectors remain sensitive to dark matter through the observation of the sec- Fig. 1. (Left) In a dual-phase TPC, scintillation light (S1) is ondary scintillation light. produced by the bombardment of an argon molecule by a Argon-based dark-matter searches have had a number of suc- dark-matter particle, upon which electrons drift upwards to a cesses in the past two years (figure 2). DarkSide-50 established the second chamber to produce electro-luminescence (S2); the availability of an underground source of argon strongly depleted distribution of S2 light gives the lateral position, while the time in the radioactive isotope 39Ar, while DEAP-3600 (figure 3), the difference between S1 and S2 gives the longitudinal position. largest (3.3 tonnes) single-phase liquid-argon running experiment, (Right) Schematic of DarkSide-50 inside a spherical 30-tonne Fig. 3. The DEAP-3600 detector during construction showing the Fig. 4. The ARIA modules for purifying liquid argon being provided the best value to date on the precision of pulse-shape organic liquid scintillator veto, which itself is contained in a sphere of inward-looking photomultipliers used for light detection. tested at CERN. discrimination for scintillation light, better than 1 part in 109. In 1000 tonne Cherenkov cosmic-ray veto. 39 terms of measurements, DarkSide-50 released results from a 500- collab. DarkSide umes of the gas from underground deposits, as argon in the Earth’s depletion of Ar by cryogenic distillation, which exploits the day detector exposure completely free of instr umental background atmosphere is unsuitable owing to its high content of the radioac- tiny dependence of the vapour pressure upon the atomic number. –38 CRESST–III 2017 10 39

and set the best exclusion limit yet for interactions of WIMPs with ) tive isotope Ar. Second, the scintillation light has to be efficiently Seruci-I is expected to reach a production capacity of 10 kg of 2 masses between 1.8 and 6 GeV/c2. Similar results to those from DarkSide–50 2018 detected, requiring innovative photodetector R&D. argon per day with a factor of 10 of 39Ar depletion per pass. This 2 (cm

SI –41 10 DarkSide–LM proj.

Darkside-50 for the mass region above 40 GeV/c were reported σ is more than sufficient to deliver – starting from the gas extracted DEAP-3600 2017 Sourcing pure argon in the first paper from DEAP-3600, and results from a one-year LUX 2017 with the Urania underground source – a one-tonne ultra-depleted- exposure of DEAP-3600 with a fiducial mass of about 1000 kg are 10–44 DarkSide–50 2018 Focusing on the first need, atmospheric argon has a radioactiv- argon target that could enable a leading programme of searches DEAP–3600LZ proj. 40 expected to be released in the near future. PANDAX II 2017 XENON1T 2018 ity of 1 Bq/kg, which is entirely caused by the activation of Ar for low-mass dark matter. Seruci-I is also expected to perform XENONnT proj. High-sensitivity searches for WIMPs using noble-gas dual- –47 by cosmic rays. Given that the drift time of ionisation electrons strong chemical purification at the rate of several tonnes per day 10 DarkSide–20k 100t yr proj. phase TPC detectors are complementary to searches conducted at DarkSide–20k 200t yr proj. over a length of 1 m is 1 ms, a dual-phase TPC detector reaches a and will be used to perform the final stage of purification for the dark matter–nucleon Future 300 tonne GADMC detector 3 kt yr proj. Future 300 tonne GADMC detector 1 kt yr proj. the Large Hadron Collider (LHC) in the mass region accessible at neutrino floor on xenon complete pile-up condition (i.e. when the event rate exceeds the 50 tonne underground argon batch for DarkSide-20k as well as for –50 the current LHC energy of 13 TeV (which is limited to masses of 10 detector’s ability to read out the information), at a mass of 1 tonne. GADMC’s final detector. 10–3 10–2 10–1 1 10 102 2 2 2 a few TeV/c ) and can reach masses of 100 TeV/c and beyond with Mχ (TeV/c ) Scintillation-only detectors do not fare much better, and given that CERN plays an important role in DarkSide-20k by carrying out very good sensitivity. the scintillation lifetime is 10 μs, they are limited to detectors with vacuum tests of the 30 modules for the Seruci-I column (figure 4) Fig. 2. Current limits on WIMP dark matter, showing the expected a fiducial mass of a few tonnes. The argon road to dark matter has and by hosting the construction of the cryogenics for DarkSide- Leading limits sensitivity from the DarkSide programme (red and green). thus required early concentration on solving the problem of procur- 20k. At the time of its approval in 2017, DarkSide-20k was set to The best limits to date on high-mass WIMPs have been provided ing large batches of argon that are much more depleted in 39Ar than be deployed within a very efficient system of neutron and cosmic- by xenon-based dual-phase TPCs – the leading result given by the tors, which are designed to have pulse-shape discrimination capable atmospheric argon is. The solution came through an unlikely path: ray rejection, based on that used for DarkSide-50 and featuring a

recently released XENON1T exposure of 1 tonne × year (figure 2). of eliminating the background from electron scatters of solar neu- the discovery that underground sources of CO2 originating from large organic liquid scintillator detector hosted within a tank of In spite of a small residual background, they were able to exclude trinos and internal radioactive decays, can provide an advantage. Earth’s mantle carry sizable quantities of noble gases, in reservoirs ultrapure deionised water. But with the deployment of new organic WIMP-nucleon spin-independent elastic-scatter cross-sections GADMC envisages a two-step programme to explore high-mass where secondary production of 39Ar is significantly suppressed. scintillator detectors now discouraged at LNGS due to tightening above 4.1 × 10 –47 cm2 at 30 GeV/c2 at 90% confidence level CERN( dark matter. The first step, DarkSide-20k, has been approved for As part of a project called Urania, funded by INFN, GADMC environmental regulations, GADMC is completing the design of Courier July/August 2018 p9). Larger xenon detectors (XENONnT construction at LNGS by Italy’s National Institute for Nuclear will soon deploy a plant that is able to extract underground argon at a large, and more environmentally friendly, liquid-argon detector and DARWIN) are also planned by the same collaboration (CERN Physics (INFN) and by the US National Science Foundation, a rate of 250 kg per day from the same site in Colorado, US, where for neutron and cosmic-ray rejection based on the cryostat technol- Courier March 2017 p35). with present and potentially future funding from Canada. Also argon for DarkSide-50 was extracted. Argon from this under- ogy developed at CERN to support prototype detector modules The next generation of xenon and argon detectors have the poten- a recognised experiment at CERN called RE-37, DarkSide-20k ground source is more depleted in 39Ar than atmospheric argon by for the future Deep Underground Neutrino Experiment (DUNE) tial to extend the present sensitivity by about a factor of 10. But is designed to collect an exposure of 100 tonne × year in a period a factor of at least 1400, making detectors of hundreds of tonnes in the US. there is still a further factor of of five years (to be possibly extended to 200 tonne × year in 10 possible for high-mass WIMP searches. Turning now to the second need of a background-free search 10 to be increased before one years), completely free of any instrumental background. The start Not content with this gift of nature, another project called for dark matter – the efficient detection of the scintillation light reaches the neutrino floor – the of data taking is foreseen for 2022–2023. The second step of the ARIA, also funded by INFN, by the Italian Ministry of University – researchers are focusing on perfecting existing technology to CERN plays an ultimate level at which interac- programme will involve building an argon detector that is able to and Research (MIUR), and by the local government of the Sar- make low-radioactivity silicon photomultipliers (SiPMs) and using tions of solar and atmospheric collect an exposure of more than 1000 tonne × year. SNOLAB in dinia region, is developing a further innovative plant to actively them to build large-area photosensors that are capable of replacing important role in neutrinos with the detector Canada is a strong candidate to host this second-stage experiment. increase the depletion in 39Ar. The plant will consist of a 350 m-tall the traditional 3ʺ cryogenic photomultipliers. Plans for DarkSide- DarkSide-20k. material become the limiting Argon can deliver the ultimate background-free search for dark cryogenic-distillation tower called Seruci-I, which is under con- 20k settled on the use of so-called NUV-HD-TripleDose SiPMs, background. This is where the matter, but that comes with extensive technological development. struction in the Monte Sinni coal mine in Sardinia operated by designed by Fondazione Bruno Kessler of Trento, Italy, and pro- GADMC liquid-argon detec- First and foremost, researchers need to extract and distill large vol- the Carbosulcis mining company. Seruci-I will study the active duced by LFoundry of Avezzano, also in Italy. In the meantime,

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CCOct18_DARKSIDE_v4.indd 22 21/09/2018 13:22 CCOct18_DARKSIDE_v4.indd 23 21/09/2018 13:23 CERNCOURIER www. V o l u m e 5 8 N u m b e r 8 O c t o b e r 2 0 1 8 CERN Courier October 2018 CERN Courier October 2018 Dark matter Dark matter CERN-PHOTO-201711-287-5 projection chamber (TPC), which contains a small region of gase- collab. DarkSide

ous argon above a larger region of liquid argon (figure 1, left). In this Ward M configuration, secondary scintillation light, generated by ionisation electrons that drift up through the liquid region and are accelerated into the gaseous one, are used together with the primary scintilla- tion light to look for a signal. Compared to single-phase detectors using only the pulse-shape discrimination technique, this search method requires even greater care in restricting the radioactive background through detector design and fabrication but provides excellent position resolution. For low-mass (<10 GeV/c2) WIMPs, the primary scintillation light is nearly absent, but the detectors remain sensitive to dark matter through the observation of the sec- Fig. 1. (Left) In a dual-phase TPC, scintillation light (S1) is ondary scintillation light. produced by the bombardment of an argon molecule by a Argon-based dark-matter searches have had a number of suc- dark-matter particle, upon which electrons drift upwards to a cesses in the past two years (figure 2). DarkSide-50 established the second chamber to produce electro-luminescence (S2); the availability of an underground source of argon strongly depleted distribution of S2 light gives the lateral position, while the time in the radioactive isotope 39Ar, while DEAP-3600 (figure 3), the difference between S1 and S2 gives the longitudinal position. largest (3.3 tonnes) single-phase liquid-argon running experiment, (Right) Schematic of DarkSide-50 inside a spherical 30-tonne Fig. 3. The DEAP-3600 detector during construction showing the Fig. 4. The ARIA modules for purifying liquid argon being provided the best value to date on the precision of pulse-shape organic liquid scintillator veto, which itself is contained in a sphere of inward-looking photomultipliers used for light detection. tested at CERN. discrimination for scintillation light, better than 1 part in 109. In 1000 tonne Cherenkov cosmic-ray veto. 39 terms of measurements, DarkSide-50 released results from a 500- collab. DarkSide umes of the gas from underground deposits, as argon in the Earth’s depletion of Ar by cryogenic distillation, which exploits the day detector exposure completely free of instr umental background atmosphere is unsuitable owing to its high content of the radioac- tiny dependence of the vapour pressure upon the atomic number. –38 CRESST–III 2017 10 39

and set the best exclusion limit yet for interactions of WIMPs with ) tive isotope Ar. Second, the scintillation light has to be efficiently Seruci-I is expected to reach a production capacity of 10 kg of 2 masses between 1.8 and 6 GeV/c2. Similar results to those from DarkSide–50 2018 detected, requiring innovative photodetector R&D. argon per day with a factor of 10 of 39Ar depletion per pass. This 2 (cm

SI –41 10 DarkSide–LM proj.

Darkside-50 for the mass region above 40 GeV/c were reported σ is more than sufficient to deliver – starting from the gas extracted DEAP-3600 2017 Sourcing pure argon in the first paper from DEAP-3600, and results from a one-year LUX 2017 with the Urania underground source – a one-tonne ultra-depleted- exposure of DEAP-3600 with a fiducial mass of about 1000 kg are 10–44 DarkSide–50 2018 Focusing on the first need, atmospheric argon has a radioactiv- argon target that could enable a leading programme of searches DEAP–3600LZ proj. 40 expected to be released in the near future. PANDAX II 2017 XENON1T 2018 ity of 1 Bq/kg, which is entirely caused by the activation of Ar for low-mass dark matter. Seruci-I is also expected to perform XENONnT proj. High-sensitivity searches for WIMPs using noble-gas dual- –47 by cosmic rays. Given that the drift time of ionisation electrons strong chemical purification at the rate of several tonnes per day 10 DarkSide–20k 100t yr proj. phase TPC detectors are complementary to searches conducted at DarkSide–20k 200t yr proj. over a length of 1 m is 1 ms, a dual-phase TPC detector reaches a and will be used to perform the final stage of purification for the dark matter–nucleon Future 300 tonne GADMC detector 3 kt yr proj. Future 300 tonne GADMC detector 1 kt yr proj. the Large Hadron Collider (LHC) in the mass region accessible at neutrino floor on xenon complete pile-up condition (i.e. when the event rate exceeds the 50 tonne underground argon batch for DarkSide-20k as well as for –50 the current LHC energy of 13 TeV (which is limited to masses of 10 detector’s ability to read out the information), at a mass of 1 tonne. GADMC’s final detector. 10–3 10–2 10–1 1 10 102 2 2 2 a few TeV/c ) and can reach masses of 100 TeV/c and beyond with Mχ (TeV/c ) Scintillation-only detectors do not fare much better, and given that CERN plays an important role in DarkSide-20k by carrying out very good sensitivity. the scintillation lifetime is 10 μs, they are limited to detectors with vacuum tests of the 30 modules for the Seruci-I column (figure 4) Fig. 2. Current limits on WIMP dark matter, showing the expected a fiducial mass of a few tonnes. The argon road to dark matter has and by hosting the construction of the cryogenics for DarkSide- Leading limits sensitivity from the DarkSide programme (red and green). thus required early concentration on solving the problem of procur- 20k. At the time of its approval in 2017, DarkSide-20k was set to The best limits to date on high-mass WIMPs have been provided ing large batches of argon that are much more depleted in 39Ar than be deployed within a very efficient system of neutron and cosmic- by xenon-based dual-phase TPCs – the leading result given by the tors, which are designed to have pulse-shape discrimination capable atmospheric argon is. The solution came through an unlikely path: ray rejection, based on that used for DarkSide-50 and featuring a

recently released XENON1T exposure of 1 tonne × year (figure 2). of eliminating the background from electron scatters of solar neu- the discovery that underground sources of CO2 originating from large organic liquid scintillator detector hosted within a tank of In spite of a small residual background, they were able to exclude trinos and internal radioactive decays, can provide an advantage. Earth’s mantle carry sizable quantities of noble gases, in reservoirs ultrapure deionised water. But with the deployment of new organic WIMP-nucleon spin-independent elastic-scatter cross-sections GADMC envisages a two-step programme to explore high-mass where secondary production of 39Ar is significantly suppressed. scintillator detectors now discouraged at LNGS due to tightening above 4.1 × 10 –47 cm2 at 30 GeV/c2 at 90% confidence level CERN( dark matter. The first step, DarkSide-20k, has been approved for As part of a project called Urania, funded by INFN, GADMC environmental regulations, GADMC is completing the design of Courier July/August 2018 p9). Larger xenon detectors (XENONnT construction at LNGS by Italy’s National Institute for Nuclear will soon deploy a plant that is able to extract underground argon at a large, and more environmentally friendly, liquid-argon detector and DARWIN) are also planned by the same collaboration (CERN Physics (INFN) and by the US National Science Foundation, a rate of 250 kg per day from the same site in Colorado, US, where for neutron and cosmic-ray rejection based on the cryostat technol- Courier March 2017 p35). with present and potentially future funding from Canada. Also argon for DarkSide-50 was extracted. Argon from this under- ogy developed at CERN to support prototype detector modules The next generation of xenon and argon detectors have the poten- a recognised experiment at CERN called RE-37, DarkSide-20k ground source is more depleted in 39Ar than atmospheric argon by for the future Deep Underground Neutrino Experiment (DUNE) tial to extend the present sensitivity by about a factor of 10. But is designed to collect an exposure of 100 tonne × year in a period a factor of at least 1400, making detectors of hundreds of tonnes in the US. there is still a further factor of of five years (to be possibly extended to 200 tonne × year in 10 possible for high-mass WIMP searches. Turning now to the second need of a background-free search 10 to be increased before one years), completely free of any instrumental background. The start Not content with this gift of nature, another project called for dark matter – the efficient detection of the scintillation light reaches the neutrino floor – the of data taking is foreseen for 2022–2023. The second step of the ARIA, also funded by INFN, by the Italian Ministry of University – researchers are focusing on perfecting existing technology to CERN plays an ultimate level at which interac- programme will involve building an argon detector that is able to and Research (MIUR), and by the local government of the Sar- make low-radioactivity silicon photomultipliers (SiPMs) and using tions of solar and atmospheric collect an exposure of more than 1000 tonne × year. SNOLAB in dinia region, is developing a further innovative plant to actively them to build large-area photosensors that are capable of replacing important role in neutrinos with the detector Canada is a strong candidate to host this second-stage experiment. increase the depletion in 39Ar. The plant will consist of a 350 m-tall the traditional 3ʺ cryogenic photomultipliers. Plans for DarkSide- DarkSide-20k. material become the limiting Argon can deliver the ultimate background-free search for dark cryogenic-distillation tower called Seruci-I, which is under con- 20k settled on the use of so-called NUV-HD-TripleDose SiPMs, background. This is where the matter, but that comes with extensive technological development. struction in the Monte Sinni coal mine in Sardinia operated by designed by Fondazione Bruno Kessler of Trento, Italy, and pro- GADMC liquid-argon detec- First and foremost, researchers need to extract and distill large vol- the Carbosulcis mining company. Seruci-I will study the active duced by LFoundry of Avezzano, also in Italy. In the meantime,

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CCOct18_DARKSIDE_v4.indd 22 21/09/2018 13:22 CCOct18_DARKSIDE_v4.indd 23 21/09/2018 13:23 CERNCOURIER www. V o l u m e 5 8 N u m b e r 8 O c t o b e r 2 0 1 8 CERN Courier October 2018 Dark matter Introducing...Best Cyclotron & Best Particle Therapy Systems from TeamBest® Companies! researchers at LNGS and other institutions succeeded in overcom- created by low-mass dark matter. On the heels of the SCENE pro- ing the huge capacitance per unit surface (50 pF/mm2) required to gramme that took place at the University of Notre Dame Tandem Best Cyclotron Systems provides 15/20/25/30/35/70 MeV build photosensors that have an area of 25 cm2 and deliver a sig- accelerator in 2013–2015, the R&D programme, developed at the nal-to-noise ratio of 15 or larger. A new INFN facility, the Nuova University of Naples Federico II and now installed at the INFN Proton Cyclotrons as well as 35 & 70 MeV Multi-Particle Officina Assergi, was designed to enable the high-throughput pro- Laboratori Nazionali del Sud, plans to improve the characterisa- (Alpha, Deuterons & Protons) Cyclotrons duction of SiPMs to make such photosensors for DarkSide-20k and tion of the argon response to nuclear recoils. Of special interest is future detectors, and it is now under construction. the extension of measurements to 1 keV, in support of searches for Currents from 100uA to 1000uA (or higher) depending GADMC’s programme is complemented by a world-class effort low-mass dark matter, and the verification of the possible depend- on the particle beam to calibrate noble-liquid detectors for low-energy nuclear recoils ence of the nuclear-recoil signals upon the direction of the initial recoil momentum relative to the drift elec- Best 20u and 30u are fully upgradeable on site tric field, which would enable measurements below the neutrino floor. Directionality in Energy Cyclotron Isotopes Produced PT2026 NMR Precision Teslameter argon has already been established for alpha (MeV) particles, protons and deuterons, and its 18F, 99mTc, 11C, 13N, 15O, presence for nuclear recoils was hinted at by Best 15 15 Reach new heights the last results of the SCENE experiment. 64Cu, 67Ga, 124I, 103Pd Although only recently established, in magnetic eld GADMC is enthusiastically pursuing Best 20u/25 20, 25–15 Best 15 + 123I, 111In, 68Ge/68Ga this long-term, staged approach to dark- measurement matter detection in a background-free mode, Best 30u which has great discovery potential extend- 30 Best 15 + 123I, 111In, 68Ge/68Ga (Upgradeable) The Metrolab PT2026 sets a new ing all the way to the neutrino floor and perhaps beyond. standard for precision magnetometers. Greater production of Best 35 35–15 Best 15, 20u/25 isotopes Leveraging 30 years of expertise building Further reading Installation of Best 70 MeV • plus 201Tl, 81Rb/81Kr the world’s gold standard magnetometers, DEAP-3600 Collaboration 2018 Phys. Rev. Lett. 121 071801. Cyclotron at Italian National it takes magnetic  eld measurement to DarkSide Collaboration 2018 Phys. Rev. Lett. 121 111303. 82Sr/82Rb, 123I, 67Cu, Laboratories (INFN), Legnaro, IT Best 70 70–35 new heights: measuring higher elds with DarkSide Collaboration 2018 Phys. Rev. Lett. 121 081307. 81Kr + research DarkSide Collaboration 2018 Eur. Phys. J. Plus 133 131. better resolution. Résumé Proton-to-Carbon High Energy The PT2026 offers unprecedented  exibility Traquer la matière noire sans bruit de fond Particle Delivery System: in the choice of parameters, interfacing and probe placement, as well as greatly Des laboratoires de plusieurs pays à travers Intrinsically small beams facilitating improved tolerance of inhomogeneous le monde unissent leurs forces en vue d’une beam delivery with precision future expérience, DarkSide-20k, qui mènera elds. And with Ethernet & USB interfaces la quête la plus complète jusqu’ici pour trouver Small beam sizes – small magnets, and LabVIEW software, it  ts perfectly into des particules de matière noire de masse élevée. light gantries – smaller footprint modern laboratory environments. Établie au Laboratoire national du Gran Sasso (Italie), l’expérience utilisera des détecteurs

www.agence-arca.com - Photo: Scott Maxwell, Master le - Photo: Scott Maxwell, Master www.agence-arca.com Highly efficient single turn extraction à argon liquide de pointe afin d’éliminer les sources de bruit de fond et d’accroître ainsi Efficient extraction – less shielding la sensibilité aux particules de matière noire. Pour répondre aux besoins de DarkSide, des Flexibility – protons and/or carbon, technologies pour l’extraction de l’argon future beam delivery modalities purifié sont actuellement développées en partenariat avec le CERN. Un groupe de travail appelé Global Argon Dark Matter ion Rapid Cycling Collaboration et consacré à ce projet a été créé Medical Synchrotron en septembre 2017 et travaille au déploiement (iRCMS) Pantone 286 Pantone 032 imminent du détecteur.

Giuliana Fiorillo, University of Naples Federico II and INFN Napoli; Art McDonald, Queen’s Magnetic precision has a name www.metrolab.com University; and Cristiano Galbiati, and Gran Sasso Science Institute. TeamBest Companies © 2017–2018 Specifications shown are subject to change.

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CCOct18_DARKSIDE_v4.indd 24 21/09/2018 13:23 BCS_BPT_UPDATEDpics_ComboAd_CERNCourier_213x282mm_v22_01022018_press.indd 1 1/2/18 4:35:02 PM CERNCOURIER www. V o l u m e 5 8 N u m b e r 8 O c t o b e r 2 0 1 8 CERN Courier October 2018 Dark matter Introducing...Best Cyclotron & Best Particle Therapy Systems from TeamBest® Companies! researchers at LNGS and other institutions succeeded in overcom- created by low-mass dark matter. On the heels of the SCENE pro- ing the huge capacitance per unit surface (50 pF/mm2) required to gramme that took place at the University of Notre Dame Tandem Best Cyclotron Systems provides 15/20/25/30/35/70 MeV build photosensors that have an area of 25 cm2 and deliver a sig- accelerator in 2013–2015, the R&D programme, developed at the nal-to-noise ratio of 15 or larger. A new INFN facility, the Nuova University of Naples Federico II and now installed at the INFN Proton Cyclotrons as well as 35 & 70 MeV Multi-Particle Officina Assergi, was designed to enable the high-throughput pro- Laboratori Nazionali del Sud, plans to improve the characterisa- (Alpha, Deuterons & Protons) Cyclotrons duction of SiPMs to make such photosensors for DarkSide-20k and tion of the argon response to nuclear recoils. Of special interest is future detectors, and it is now under construction. the extension of measurements to 1 keV, in support of searches for Currents from 100uA to 1000uA (or higher) depending GADMC’s programme is complemented by a world-class effort low-mass dark matter, and the verification of the possible depend- on the particle beam to calibrate noble-liquid detectors for low-energy nuclear recoils ence of the nuclear-recoil signals upon the direction of the initial recoil momentum relative to the drift elec- Best 20u and 30u are fully upgradeable on site tric field, which would enable measurements below the neutrino floor. Directionality in Energy Cyclotron Isotopes Produced PT2026 NMR Precision Teslameter argon has already been established for alpha (MeV) particles, protons and deuterons, and its 18F, 99mTc, 11C, 13N, 15O, presence for nuclear recoils was hinted at by Best 15 15 Reach new heights the last results of the SCENE experiment. 64Cu, 67Ga, 124I, 103Pd Although only recently established, in magnetic eld GADMC is enthusiastically pursuing Best 20u/25 20, 25–15 Best 15 + 123I, 111In, 68Ge/68Ga this long-term, staged approach to dark- measurement matter detection in a background-free mode, Best 30u which has great discovery potential extend- 30 Best 15 + 123I, 111In, 68Ge/68Ga (Upgradeable) The Metrolab PT2026 sets a new ing all the way to the neutrino floor and perhaps beyond. standard for precision magnetometers. Greater production of Best 35 35–15 Best 15, 20u/25 isotopes Leveraging 30 years of expertise building Further reading Installation of Best 70 MeV • plus 201Tl, 81Rb/81Kr the world’s gold standard magnetometers, DEAP-3600 Collaboration 2018 Phys. Rev. Lett. 121 071801. Cyclotron at Italian National it takes magnetic  eld measurement to DarkSide Collaboration 2018 Phys. Rev. Lett. 121 111303. 82Sr/82Rb, 123I, 67Cu, Laboratories (INFN), Legnaro, IT Best 70 70–35 new heights: measuring higher elds with DarkSide Collaboration 2018 Phys. Rev. Lett. 121 081307. 81Kr + research DarkSide Collaboration 2018 Eur. Phys. J. Plus 133 131. better resolution. Résumé Proton-to-Carbon High Energy The PT2026 offers unprecedented  exibility Traquer la matière noire sans bruit de fond Particle Delivery System: in the choice of parameters, interfacing and probe placement, as well as greatly Des laboratoires de plusieurs pays à travers Intrinsically small beams facilitating improved tolerance of inhomogeneous le monde unissent leurs forces en vue d’une beam delivery with precision future expérience, DarkSide-20k, qui mènera elds. And with Ethernet & USB interfaces la quête la plus complète jusqu’ici pour trouver Small beam sizes – small magnets, and LabVIEW software, it  ts perfectly into des particules de matière noire de masse élevée. light gantries – smaller footprint modern laboratory environments. Établie au Laboratoire national du Gran Sasso (Italie), l’expérience utilisera des détecteurs

www.agence-arca.com - Photo: Scott Maxwell, Master le - Photo: Scott Maxwell, Master www.agence-arca.com Highly efficient single turn extraction à argon liquide de pointe afin d’éliminer les sources de bruit de fond et d’accroître ainsi Efficient extraction – less shielding la sensibilité aux particules de matière noire. Pour répondre aux besoins de DarkSide, des Flexibility – protons and/or carbon, technologies pour l’extraction de l’argon future beam delivery modalities purifié sont actuellement développées en partenariat avec le CERN. Un groupe de travail appelé Global Argon Dark Matter ion Rapid Cycling Collaboration et consacré à ce projet a été créé Medical Synchrotron en septembre 2017 et travaille au déploiement (iRCMS) Pantone 286 Pantone 032 imminent du détecteur.

Giuliana Fiorillo, University of Naples Federico II and INFN Napoli; Art McDonald, Queen’s Magnetic precision has a name www.metrolab.com University; and Cristiano Galbiati, Princeton University and Gran Sasso Science Institute. TeamBest Companies © 2017–2018 Specifications shown are subject to change.

24 www.bestcyclotron.com • www.bestproton.com • www.teambest.com

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