Difference: OldFiles (1 vs. 2)

• Set MYTITLE = CLIC Muon Background Simulation Using BDSIM - History

File 1 - BUGS

• muons_e-_1500GeV.dat: Muons at the entrance to QD0 from 1500 G eV halo electrons hitting YSP1. File format:

Energy[GeV] x[m] y[m] x' y' partID z0[m] weight

Energy is the energy of the particle in G eV. x and y are the positions of the particle from the reference trajectory in metres. x' and y' are the normalised components of the momentum vector along the two axes. partID is the PDG particle code (for muons, partID=-13, for antimuons partID=13). z0 is the position along the z axis of the last interaction of the particle. weight is the weight factor, which depends upon the cross section biasing factor of the process in which the particle was generated and the weight of the parent particle.

At 1.5 T eV, the dominant process is gamma-> mu- mu+ and electron positron annihilation can be ignored. Therefore electrons incident and positrons incident produce similar numbers of muons.

The number of primaries used to generate this file was N_p = 51232, with the cross sections weighted by the following factors:

gamma -> muons: 1e4 annihilation -> muons: 1e6

The number of muons/antimuons per primary halo particle hitting the sampler at QD0 is (1.949 +/- 0.033) X 10^(-5). Assuming 2 X 10^(10) particles per bunch, and a halo population factor of 10^(-3), there are 389.8 +/- 6.6 muons/antimuons per bunch (here +/- is the statistical uncertainty in the estimate of the mean).

<--
 Settings just to customise this page 
 

 Set STYLESIDEBAR = off
 
 Set ALLOWTOPICVIEW = TWikiGuest, JohnAdamsInstituteGroup
 
 Set MYTITLE = CLIC Muon Background Simulation Using BDSIM
 
-->

File 2 18th March 2010 - BUGS

• muons_3m_upstream_qd0_e-_1500GeV.txt: Muons 3m upstream of the entrance to QD0 from 1500 G eV halo electrons hitting YSP1. File format:

x' y' z' x[mum] y[mum] z[m] charge[e] energy[GeV]

Energy is the energy of the particle in G eV. x and y are the positions of the particle from the reference trajectory in mum. x' y' and z' are the normalised components of the momentum vector along the three axes.

At 1.5 T eV, the dominant process is gamma-> mu- mu+ and electron positron annihilation can be ignored. Therefore electrons incident and positrons incident produce similar numbers of muons.

The number of primaries used to generate this file was N_p = 46569, with the cross sections weighted by the following factors:

gamma -> muons: 1e4

annihilation -> muons: 1e4

The number of muons/antimuons per primary halo particle hitting the sampler at QD0 is (1.616 +/- 0.012) X 10^(-5). Assuming 2 X 10^(10) particles per bunch, and a halo population factor of 10^(-3), there are 323.2 +/- 2.4 muons/antimuons per bunch (here +/- is the statistical uncertainty in the estimate of the mean).

File 3 30th March 2010

• muons_e-_30_03.txt: Muons at the exit of QF1 (~3m upstream of the entrance to the final quadrupole QD0) from 1.5 T eV halo electrons hitting YSP1.

There are several changes and bug fixes.

• The beam line is now based on the latest MAD deck, v_10_01_25.
• A problem with the interface between the HTGEN output and BDSIM has been resolved.
• The width of the samplers has been increased.

The file format and cross section biasing are the same as for file 2.

The number of primaries used to generate this file was N_p = 30789

The number of muons/antimuons per primary halo particle hitting the sampler at QD0 is (5.98+/-0.04) X 10^(-5). Assuming 2 X 10^(10) particles per bunch, and a halo population factor of 10^(-3), there are 1196 +/- 8 muons/antimuons per bunch (here +/- is the statistical uncertainty in the estimate of the mean).

File 4 30th March 2010 - BUGS

===CORRECTION 9th April 2010=== * muons_swap_e-_30_03.txt: Muons at the exit of magnet QF1 from 1.5 T eV halo electrons hitting first vertical spoiler ysp1. Betatron and energy collimation section ordering is reversed.

This file was created under the same conditions as file 3, with the exception that the energy and betatron collimation sections are swapped. Therefore, muons created in the betatron collimation section have further to travel in order to reach the detector.

To swap the collimation sections the following line in the MAD file is changed:

noentrcolsys: line:=(sentr,trans1,nlcecoll,trans2,etbcoll, sexit, trans3,nlcbcoll,trans4,btff, trans5);

is changed to

noentrcolsysswap: line:=(sentr,trans1,etbcoll,trans2, nlcbcoll,sexit,trans3,nlcecoll,trans4,btff, trans5);

This keeps approximately the correct beam size at the IP (sigma x 39 nm -> 45 nm, sigma y remains at 1nm) while swapping the ordering of the betatron collimation section (nlcbcoll) and the energy collimation section (nlcecoll).

The number of primaries used to generate this file was N_p = 30386

Below is an outline file showing the layout.

* swap_v1_outline.txt: All components, positions and settings for the swapped beam line, v1

===CORRECTION 9th April 2010=== The number of muons/antimuons per primary halo particle hitting the sampler at QD0 is (9.77 +/- 0.11) X 10^(-6). Assuming 2 X 10^(10) particles per bunch, and a halo population factor of 10^(-3), there are 195 +/- 2 muons/antimuons per bunch (here +/- is the statistical uncertainty in the estimate of the mean). This is a ~84% reduction compared to file 3.

Files 5 and 6 13th April 2010

These are identical to files 3 and 4 but with additional columns:

z0[m] weight (see File 1 for explaination).

~1% of the muons are produced by gamma -> mu+ mu- from gammas emitted by muons and therefore have a weight of 1e-4*1e-4 = 1e-8.

• muons_e-_30_03_format2.txt
• muons_swap_e-_30_03_format2.txt - BUGS

Files 7 and 8 13th April 2010 - BUGS - INCORRECT APERTURES - INCORRECT LOW ENERGY CUTOFF

ALL APERTURES WERE 8mm APART FROM THE COLLIMATORS

The same as File 4 but with an improved swapped collimation sections beam delivery system layout (layout produced by Rogelio Garcia). The files are in two different formats. Format 1 is the same format as Files 3 and 4. Format 2 is the same format as Files 5 and 6 and contains extra data columns (z0, weight).

• muons_swap_e-_12_04_format1.txt: Improved swapped BDS layout (layout produced by Rogelio Garcia). Format 1.

• muons_swap_e-_12_04_format2.txt: Improved swapped BDS layout (layout produced by Rogelio Garcia). Format 2.

The number of primaries used to generate this file was N_p = 14912

The number of muons/antimuons per primary halo particle hitting the sampler at QD0 is (1.37 +/- 0.05) X 10^(-6). Assuming 2 X 10^(10) particles per bunch, and a halo population factor of 10^(-3), there are 27 +/- 1 muons/antimuons per bunch (here +/- is the statistical uncertainty in the estimate of the mean). This is a ~98% reduction compared to file 3.

Files 9 and 10 14th April 2010 BUGS - INCORRECT LOW ENERGY CUTOFF

Like files 7 and 8 but with the correct apertures.

• muons_swap_e-_14_04_format1.txt: Apertures correction

• muons_swap_e-_14_04_format2.txt: Apertures correction.

The number of primaries used to generate this file was N_p = 18600

CORRECTION 16th April 2010 The number of muons/antimuons per primary halo particle hitting the sampler at QD0 is (2.50 +/- 0.22) X 10^(-6). Assuming 2 X 10^(10) particles per bunch, and a halo population factor of 10^(-3), there are 50 +/- 4 muons/antimuons per bunch (here +/- is the statistical uncertainty in the estimate of the mean). This is a ~96% reduction compared to file 3.

Below is an outline file showing the layout for files 7, 8 ,9 and 10.

* swap_v2_outline.txt: All components, positions and settings for the swapped beam line, v2

Files 11 and 12 16th April 2010 - BUGS - INCORRECT LOW ENERGY CUTOFF

CORRECTION 16th April 2010 Files 3 - 10 did not start at the first spoiler but 57.42 metres upstream, at the start of the betatron collimation section (see outline files above).

Corrected muon and outline files are below. These are the same as files 9 and 10 but with the correct starting position.

The number of primaries used to generate this file was N_p = 14479

CORRECTION 16th April 2010 The number of muons/antimuons per primary halo particle hitting the sampler at QD0 is (2.10 +/- 0.14) X 10^(-6). Assuming 2 X 10^(10) particles per bunch, and a halo population factor of 10^(-3), there are 44 +/- 2 muons/antimuons per bunch (here +/- is the statistical uncertainty in the estimate of the mean).

CORRECTION 20 April 2010 - the wrong files were attached

• muons_e-_swap_16_04_format1.txt: muons_e-_swap_16_04_format1.txt

• muons_e-_swap_16_04_format2.txt: muons_e-_swap_16_04_format2.txt

• swap_v2_corrected_outline.txt: All components, positions and settings for the swapped beam line, v2. Corrected layout, starting at YSP1.

• CLIC_bds_swap_from_ysp1.eps: A diagram showing locations of components along the beam line. The betratron spoilers are omitted.

Files 13 and 14 16th April 2010

CORRECTION 16th April 2010 Files 3 - 10 did not start at the first spoiler but 57.42 metres upstream, at the start of the betatron collimation section (see outline files above).

Corrected muon and outline files are below. Original collimation layout.

The number of primaries used to generate this file was N_p = 30130

The number of muons/antimuons per primary halo particle hitting the sampler at QD0 is (5.56 +/- 0.01) X 10^(-5). Assuming 2 X 10^(10) particles per bunch, and a halo population factor of 10^(-3), there are 1113 +/- 2 muons/antimuons per bunch (here +/- is the statistical uncertainty in the estimate of the mean).

• muons_e-_16_04_format1.txt: muons_e-_16_04_format1.txt

• muons_e-_16_04_format2.txt: muons_e-_16_04_format2.txt

• corrected_outline.txt: Outline of BDS from first spoiler YSP1

Files 15 and 16 27th April 2010

Swapped layout. Correct 500 Me V low energy cutoff for electrons, positrons and photons.

The number of primaries used to generate this file was N_p = 12059

The number of muons/antimuons per primary halo particle hitting the sampler at QD0 is (2.274 +/- 0.09) X 10^(-5). Assuming 2 X 10^(10) particles per bunch, and a halo population factor of 10^(-3), there are 455 +/- 2 muons/antimuons per bunch (here +/- is the statistical uncertainty in the estimate of the mean). This is a 41% reduction compared to file 13.

• muons_swap_e-_27_04_format1.txt: Corrected low energy cutoff for electrons, positrons and photons.

• muons_swap_e-_27_04_format2.txt: Corrected low energy cutoff for electrons, positrons and photons.