The MEG detector for μ+→e+γ decay search Adam, J.; Bai, X.; Baldini, A. M. ...
The European physical journal. C, Particles and fields,
04/2013, Letnik:
73, Številka:
4
Journal Article
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Odprti dostop
The MEG (Mu to Electron Gamma) experiment has been running at the Paul Scherrer Institut (PSI), Switzerland since 2008 to search for the decay
μ
+
→e
+
γ
by using one of the most intense continuous
μ
...+
beams in the world. This paper presents the MEG components: the positron spectrometer, including a thin target, a superconducting magnet, a set of drift chambers for measuring the muon decay vertex and the positron momentum, a timing counter for measuring the positron time, and a liquid xenon detector for measuring the photon energy, position and time. The trigger system, the read-out electronics and the data acquisition system are also presented in detail. The paper is completed with a description of the equipment and techniques developed for the calibration in time and energy and the simulation of the whole apparatus.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Fermilab is developing a new generation of high-field superconducting magnets for future accelerators based on Nb3Sn. Rutherford-type cables of 27 and 28 strands of various structures, packing ...factors, with and without a stainless steel core, were fabricated at Fermilab out of Cu, NbTi and various Nb3Sn strands. The effect of cabling degradation was measured. A method was developed to simulate cabling and possibly understand the strains applied during the process. This paper summarizes the results of such R&D efforts at Fermilab.
The critical current of Nb/sub 3/Sn strands used in Fermilab's high field magnets was measured at low and high fields under various experimental conditions using the voltage-current (V-I) and ...voltage-field (V-H) methods. The strands were produced using Modified Jelly Roll, Restacked Rod Process and Powder-in-Tube technologies. V-I characteristics at fields above 10-12 T with a smooth transition from the superconducting to normal phase allowed determining strand critical current. V-I and V-H measurements at low fields showed premature quenches due to magnetic instability in strands with high critical current density and large effective filament size. The results of the strand critical current measurements at low and high fields are herein presented.
The MEG (Mu to Electron Gamma) experiment has been running at the Paul Scherrer Institut (PSI), Switzerland since 2008 to search for the decay μ.sup.+ → e.sup.+γ by using one of the most intense ...continuous μ.sup.+ beams in the world. This paper presents the MEG components: the positron spectrometer, including a thin target, a super-conducting magnet, a set of drift chambers for measuring the muon decay vertex and the positron momentum, a timing counter for measuring the positron time, and a liquid xenon detector for measuring the photon energy, position and time. The trigger system, the read-out electronics and the data acquisition system are also presented in detail. The paper is completed with a description of the equipment and techniques developed for the calibration in time and energy and the simulation of the whole apparatus.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The MEG (Mu to Electron Gamma) experiment has been running at the Paul Scherrer Institut (PSI), Switzerland since 2008 to search for the decay mu ^sup +^arrow righte^sup +^ γ by using one of the most ...intense continuous mu ^sup +^ beams in the world. This paper presents the MEG components: the positron spectrometer, including a thin target, a superconducting magnet, a set of drift chambers for measuring the muon decay vertex and the positron momentum, a timing counter for measuring the positron time, and a liquid xenon detector for measuring the photon energy, position and time. The trigger system, the read-out electronics and the data acquisition system are also presented in detail. The paper is completed with a description of the equipment and techniques developed for the calibration in time and energy and the simulation of the whole apparatus.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The critical current of Nb sub(3)Sn strands used in Fermilab's high field magnets was measured at low and high fields under various experimental conditions using the voltage-current (V-I) and ...voltage-field (V-H) methods. The strands were produced using Modified Jelly Roll, Restacked Rod Process and Powder-in-Tube technologies. V-I characteristics at fields above 10-12 T with a smooth transition from the superconducting to normal phase allowed determining strand critical current. V-I and V-H measurements at low fields showed premature quenches due to magnetic instability in strands with high critical current density and large effective filament size. The results of the strand critical current measurements at low and high fields are herein presented.
Ionization cooling, a method for shrinking the size of a muon beam, requires a low Z energy absorber, high-field magnets, and high gradient RF. We have studied the use of hydrogen systems to provide ...ionization energy loss for muon beam cooling, breakdown suppression for pressurized high-gradient RF cavities, and refrigeration for superconducting magnets and cold RF cavities. We report progress on the designs of cryostat and refrigeration systems for different sections of muon cooling channels to achieve safe and robust means to enable exceptionally bright muon beams. We find that engineering designs can be greatly simplified if high temperature superconductor can be used that has the capability to carry adequate current in fields above 10 T for temperatures above 33 K for the use of integrated pressurized RF cavities, or for temperatures above 16 K for designs where the RF and cooling sections are sequential.
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