marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 1 Transmittance, scraping and maximum radii for MICE STEPVI M. Apollonio – University of Oxford
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 2 Amplitude – a single particle concept Amplitude – also known as ‘single particle emittance’ = SPE Focussing magnetic field Particle (muon) performs oscillations about beam axis x’’ + k 2 (s) x = 0 (Hill’s eqn) k 2 (s) = focussing strength A = amplitude of betatron oscillations A is constant of motion in linear system Particle moves on ellipse of fixed area = A in x, x’ space x x’
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 3 Amplitude (single particle property) A = x xx’ + x’ 2 are optical (Twiss) parameters Emittance (many particle description) rms amplitude of beam Normalise by multiplying by p/mc Optical parameters from covariance matrix of a set of muons or from magnetic field At focus or in uniform field: A = x 2 / + x’ 2 A n = (p/mc) A = p x 2 /( mc) + p t 2 / (p mc) = p / (150 [MeV ] B [T] ) in uniform field x x’ x max = sqrt ( A) (ECALC9 does all this) MICE can measure single muon amplitudes
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 4 Scattering HEATS on average COOL by reducing p t Increase central phase space density, i.e. increase density at low amplitudes x ptpt
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 5 Abs RF Abs RF Abs Absorbers & RF cavities in channel scrape beam Scraping can be described in terms of normalised amplitude A n = (p/m) R 2 / p = 200 MeV/c R (cm) (cm) A n max (cm) Absorber RF Tracker Tracker is ‘bigger’ than channel – good! 2.Note: Full scraping will be seen only in a long channel (1 betatron oscillation)
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 6 parameters used in simulation (ICOOL) TRANSMITTANCE Define a VACUUM channel (NO ABS, NO RF) and a large aperture upstream/downstream trackers 40cm + vacuum channel + 40cm + 90cm Evaluate amplitude upstream/downstream and do the ratio=transmission/amplitude Max radius (effect of scraping) and cooling Use the realistic channel (real radii) Select throughoing muons Record the max radius for every z-slice Parameters used in ICOOL simulation Pz=240, 200, (170) MeV/c with no gaussian spread initial emittances: 0.1, 0.3, 0.6, 1.0, 2.0, 3.0 (cm rad) generated muons per initial emittance 128 positions along Z to study the amplitudes of the beam (Single Particle Emittance)
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 7 NuNu NdNd T=N d /N u Scheme for transmission study: No selection on muons Ratio between downstream and upstream particles Scheme for max radius and cooling study: selection on muons only throughgoing accepted Search for max value of radial distribution R=40 cm R=90 cm Z u =-5.2 mZ d =-5.2 m
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 8 RF ABS Tracker TRANSMISSION Amplitude ICOOL NO material or RF Soft edge Compare with long channel
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 9 the case of a LONG channel (a la NF), ~90 m of MICE repeated cells Bz (T) Pz (GeV/c) Beta (m)m
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 10 P Z =200 MeV/c, abs =42 cm e=2.0cm rad e=3.0cm rad Long channel Harder edge as expected
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 11 MICE STEP VI ~90m of MICE Channel
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 12 CAVEAT: The RF is designed to work with a beam of ~200 MeV/c When working with 240/170 MeV/c the RF config should be changed properly I did it “by hand” changing the phase and the peak voltage Discovered recently (last analysis PC) COOLING USING AMPLITUDE
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 13 N.B. 200 MeV/c: 8.74 MV/m – 90 deg P (GeV/c) Z (m) Still not perfect … 9.1 MV/m – ph.shift=30 deg Pz=170 MeV/c emi=1 mm rad Z (m) P (GeV/c) 8.74 MV/m – ph.shift=130 deg Pz=240 MeV/c emi=1 mm rad 8.74 MV/m ph.shift=90
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 14 beam maximum radius + cooling
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) cm rad 0.3 cm rad 0.6 cm rad 1.0 cm rad 2.0 cm rad 3.0 cm rad P Z =200 MeV/c, abs =42 cm MICE profile in ICOOL sim
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 16 =0.1cm rad =0.3cm rad downstream P Z =200 MeV/c, abs =42 cm ratio 40K heating cooling
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 17 =1.0 cm rad =0.6cm rad P Z =200 MeV/c, abs =42 cm
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 18 =2.0 cm rad =3.0 cm rad P Z =200 MeV/c, abs =42 cm
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) cm rad 0.3 cm rad 0.6 cm rad 1.0 cm rad 2.0 cm rad 3.0 cm rad P Z =240 MeV/c, abs =42 cm
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 20 =0.1cm rad downstream =0.3cm rad P Z =240 MeV/c, abs =42 cm 40K
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 21 e=0.6cm rad e=1.0cm rad P Z =240 MeV/c, abs =42 cm
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 22 e=3.0cm rad e=2.0cm rad P Z =240 MeV/c, abs =42 cm
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) cm rad 0.3 cm rad 0.6 cm rad 1.0 cm rad 2.0 cm rad 3.0 cm rad P Z =170 MeV/c, abs =15 cm
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 24 =0.1cm rad downstream =0.3cm rad P Z =170 MeV/c, abs =15 cm 40K
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 25 =0.6cm rad downstream =1.0cm rad P Z =170 MeV/c, abs =15 cm
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 26 =2.0 cm rad downstream =3.0 cm rad P Z =170 MeV/c, abs =15 cm
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 27 transmittance
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 28 P Z =200 MeV/c, abs =42 cm =0.1cm rad =0.3cm rad
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 29 P Z =200 MeV/c, abs =42 cm e=0.6cm rad e=1.0cm rad
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 30 P Z =200 MeV/c, abs =42 cm e=2.0cm rad e=3.0cm rad
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 31 P Z =170 MeV/c, abs =15 cm !!!! 4K !!!!
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 32 P Z =170 MeV/c, abs =15 cm
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 33 P Z =170 MeV/c, abs =15 cm
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 34 P Z =240 MeV/c, abs =42 cm
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 35 P Z =240 MeV/c, abs =42 cm
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 36 P Z =240 MeV/c, abs =42 cm
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 37 the case of a LONG channel (a la NF), ~90 m of MICE repeated cells Bz (T) Pz (GeV/c) Beta (m)m
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 38 P Z =200 MeV/c, abs =42 cm =0.1cm rad =0.3cm rad
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 39 P Z =200 MeV/c, abs =42 cm e=0.6cm rad e=1.0cm rad
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 40 P Z =200 MeV/c, abs =42 cm e=2.0cm rad e=3.0cm rad
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 41
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 42
marco apollonio/J.CobbMICE coll. meeting 16- RAL - (10/10/2006) 43