Development of the superconducting solenoid for the CMD-2M detector

AbstractThethinsuperconductingsolenoidfortheCMD-2Mdetectorisdescribed.Thesuperconductingsolenoidproducesamagneticfieldupto1:5Tinavolumeof+0:7 0:9m 2 : ThecoilisindirectlycooledbyLHeat4:2K: Itisalsoshuntedbyuniformlydistributedresistorsthatprovidequenchprotectionofthesolenoid.Theradiationthicknessofthecoilis0:08X 0 : ThesolenoidismanufacturedinBINP.r 2002ElsevierScienceB.V.Allrightsreserved. PACS: 82.25.LyKeywords: Thinsuperconductingsolenoid;Shuntresistorsprotection;Fluxpump 1. IntroductionThe CMD-2M detector [1] is being built inBudkerInstituteofNuclearPhysicsfortheVEPP-2000collider[2].Thesuperconductingsolenoidforthe CMD-2M detector must produce a magneticfieldof1:5T: Itisalmostcommoninhigh-energyphysics that one of the principal demands to thedetectormagnetdesignisthatthecoilmustbeasthin as possible in terms of radiation lengthwithout sacrificing the operational safety andreliabilityofthemagnet.Sothissuperconductingcoil was designed to have 0:08X 0 : Such value isachievable due to the shunt resistors quenchprotection method applied to this design. Thiskind of the quench protection was used for thesuperconducting solenoid of the CMD-2 detector[3].2. Design conception of the superconductingsolenoidThelayoutoftheCMD-2MdetectorisshowninFig.1. The superconducting solenoid is placedbetweentheZ-chamberandtheLXecalorimeter.The vacuum vessel of the solenoid and LXecalorimeter is common that allows eliminatingadditionalmaterialofvacuumwallsandradiationshields.Themainparametersofthesuperconduct-ingsolenoidarelistedinTable1.Thesolenoidtogetherwithradiationshieldsareplaced between the warm walls in the space of28mm that demands the geometric thickness of