6 April 2006, LGStatus Report Beam Working Group1 Beam Working Group Status Report 6 April 2006 Presented by Lau Gatignon Cedar status MNP33-2 Outgassing studies Beam design
6 April 2006, LGStatus Report Beam Working Group2 CEDAR (plur R.Malleyran), picture from 1976:
6 April 2006, LGStatus Report Beam Working Group3 CEDAR internal structure (+ Claude Bovet)
6 April 2006, LGStatus Report Beam Working Group4 Part of diaphragm
6 April 2006, LGStatus Report Beam Working Group5 Beam Diaphragm Many PMT’s Light condensor Cedar design: Use ellipsoidal mirrors (tilted at 45 o ) to produce larger light spot Use segmented photon detectors to lower rate per channel Simulation includes: absolute production rate according to N pe = N o L sin 2 with N o = 370 eV -1 cm -1 e E over range Å parabolic approximation of quantum efficiency: 25% at 4000 Å, 9% at 2000, 6000 Å 10x10 mm 2 PMT’s with 8x8 mm 2 sensitive area Cedar without ‘nose’, realistic beam parameters, scattering in H 2
6 April 2006, LGStatus Report Beam Working Group6
6 April 2006, LGStatus Report Beam Working Group7 100 transverse,140 radial [2800,4400 A] 60x30 mm 2 light spot! X of seen p.e. at PM location [mm] X at PM [mm] Y at PM [mm]
6 April 2006, LGStatus Report Beam Working Group8
6 April 2006, LGStatus Report Beam Working Group9 OR at each PMT location, ‘old logic’ : 50 MHz * 23 PMT out of 8 * 6*3 = 144 8 MHz per PMT
6 April 2006, LGStatus Report Beam Working Group10 Define symmetry of cells hit: Symmetry = 1-(Asym X * Asym Y ) Cut Symmetry Symmetry * #cells hit
6 April 2006, LGStatus Report Beam Working Group11
6 April 2006, LGStatus Report Beam Working Group12 For 1.5 mm diaphragm gap, cut at Symm*Nr cells > 7:
6 April 2006, LGStatus Report Beam Working Group13 Laser +attenuator assembly Alfredo Placci
6 April 2006, LGStatus Report Beam Working Group14 R x10mm2 Specs Alfredo Placci
6 April 2006, LGStatus Report Beam Working Group15 Hamamatsu R2248 Divider HV 1200 V Pulser laser 30 MHz Noise(1 p.e.) 13 mV average, 5 mV sigma Pulse height 66 mV average, 28 mV sigma Alfredo Placci
6 April 2006, LGStatus Report Beam Working Group16 Alfredo Placci
6 April 2006, LGStatus Report Beam Working Group17 MAPM H6568 HV 1000V Left: Pulse rate 30 MHz p.h. 147 mV,sigma 45 mV Right:Pulse rate 50 MHz, p.h. 140 mV, sigma 40 mV Alfredo Placci
6 April 2006, LGStatus Report Beam Working Group18 MAPM pulse height vs laser frequency(1.5 ns width, 0.8 ns rise-time) for various HV’s: move 800 V, yellow 900V,blue 1000 V, upper 1100V Alfredo Placci
6 April 2006, LGStatus Report Beam Working Group19 MNP33-2 requires a field integral times higher ( 1.2 Tm ) with a similar field distribution in between the 2.4 m pole vertical aperture. This can be obtained with a slight increase of the magnet length. The design aim is also to keep the maximum current at a value not too far from that of MNP33-1, for obvious reason of cost optimization the available power is (from J.P. Burnet information): NR A / 600V DC NR31-07+ND A / 600V DC Marcello Losasso
6 April 2006, LGStatus Report Beam Working Group m 4.4 m 4 m 2.5 m MNP33-2 upgraded; how it could be Marcello Losasso
6 April 2006, LGStatus Report Beam Working Group21 Bdl is 1.1 Tm in a range -2.5 m to 2.5 m Bdl is 1.2 Tm in a range -4 m to 4 m Bmax = 0.36 T Marcello Losasso Marcello will provide field map at straw planes – is this acceptable for straws?
6 April 2006, LGStatus Report Beam Working Group22 Total weight of iron is around 130 ton A cost of 3 ckf/Kg (including machining) can be reasonably expected Iron price can be estimated around 400 Kchf Marcello Losasso
6 April 2006, LGStatus Report Beam Working Group23 Coil Cross section: 0.29 m x 0.29 m Current is 2.3 KA Conductor is 21 x 21 mm (with 10 mm cooling hole) Total number of turns x coil is 196 x coil Current density in Cu is about 7 A/mm2 Total length of conductor x coil is about 3 Km (10 ton) Marcello Losasso
Update on outgassing measurements 1. Blue tube 2005 test2006 test Duration of pumping, days1015 Vacuum reached, mbar3 · · Average outgassing, (mbar l)/(sec cm 2 )1.6 · · High vacuum outgassing, (mbar l)/(sec cm 2 )3 · · Outgassing load (high vacuum), (mbar l)/sec1 · Worst (dynamic) outgassing, (mbar l)/(sec cm 2 )6.5 · Worst outgassing load (dynamic), (mbar l)/sec4.8 · Preliminary mass spectrometer measurement shows that the main gas component is water Valeri Falaleev
6 April 2006, LGStatus Report Beam Working Group25 Valeri Falaleev
6 April 2006, LGStatus Report Beam Working Group26 2. Scintillator 20 plate proto in big tank 2 plates in small tank CKM Number of days to reach stable pressure days of pumping Average outgassing, (mbar l)/(sec cm 2 )7 · · ·10-9 Worst outgassing, (mbar l)/(sec cm 2 )2 · Valeri Falaleev
6 April 2006, LGStatus Report Beam Working Group27 Valeri Falaleev
6 April 2006, LGStatus Report Beam Working Group28 3. Blue tube + Scintillator Reasonable case Worst case Blue tube outgassing load (mbar l)/sec1 · · Scintillator outgassing load (mbar l)/sec5.1 · · Total outgassing load (mbar l)/sec6.1 · · Pump power needed to reach 1 · mbar (100% conductance), l/sec 6.1 · · 10 4 Blue tubeScintillator “Reasonable” outgassing, (mbar l)/(sec cm 2 )1.35 · · Surface, cm · · 10 7 Reminder: 5 · 10 4 l/sec pumps are available on the market Valeri Falaleev
6 April 2006, LGStatus Report Beam Working Group29 Niels This is of some importance already now because it impacts on the design of the TAX and the choice of holes
6 April 2006, LGStatus Report Beam Working Group30 Niels
6 April 2006, LGStatus Report Beam Working Group31 Niels
6 April 2006, LGStatus Report Beam Working Group32 Niels
6 April 2006, LGStatus Report Beam Working Group33 Niels