Contents of this memo by xzibit

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									Contents of this memo
In the original report (vrvs_2003-09-01.ppt), straight-track-chargedevents are reproduced well whereas bent track events and neutral ones showed some discrepancy, indicating that 2ndary models need to be modified. Referring to papers of Balloon measurements, new proton/e-/e+/muon/gamma 2ndary models are constructed and proposed here. Updated TKR hit distributions and the number of tracks distributions are also presented.

pp. 2-6: New models pp. 7-10: Updated TKR hit distribution pp. 11-12: Updated the number of reconstructed tracks distribution

vrvs_2003-09-01_appendix.ppt

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New model(1): muon
new models

original model(mu-)

Reference: Boezio et al. 2000, Phys. Rev. D 62, 032007vrvs_2003-09-01_appendix.ppt 2

New model (2): proton
original model

new models •downward •upward – keep the original model
Don’t care about vertical line at 4GeV! (This is due to a bug in root.)

Reference: •Alcaratz et al. 2000, Phys. Let. B 472, 215 •Abe et al. 2003, Phys. Let. B. 564, 8 •Verma 1967, JGR 72, 915 •Pennypacker et al. 1973, JGR 78, 1515
vrvs_2003-09-01_appendix.ppt 3

New model (3): gamma 2ndary
Angular distribution (left) and energy spectrum (right). Original model is shown in black line and the new in red.

Due to bug in root. Please ignore…
vrvs_2003-09-01_appendix.ppt 4

New model (4): e-/e+

new model

original model

Please ignore this…

Reference: •Alcaratz et al. 2000, Phys. Letters B 484, 10 •Barwick et al. 1998, JGR 103, 4817 •Verma 1967, JGR 72, 915 •Israel 1969, JGR 74, 4701
vrvs_2003-09-01_appendix.ppt 5

And more…
•Take an attenuation by air into account. Assuming density of air above detector to be 4g/cm^2 and Nuclear collision length 60g/cm^2, use the attenuation factor (for proton and alpha primary) as below. •Exp(-1./15*cos(tehta)) for cos(theta)>=0.2 •Exp(-1./15*0.2) for cos(theta)=0.2 •Reduce primary proton flux by 10%

vrvs_2003-09-01_appendix.ppt

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TKR hit distribution (1)
Hit rate of each layer for charged events.
original model
data muon gamma e-/e+ alpha proton

new model

vrvs_2003-09-01_appendix.ppt

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TKR hit distribution (2)
Hit rate of each layer for neutral events.
original model
gamma upward gamma downward

new model

vrvs_2003-09-01_appendix.ppt

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TKR hit distribution (3)
Hit rate of each layer for charged events, where the primary track (the track the reconstruction program gives back first) is straight. original model
new model

vrvs_2003-09-01_appendix.ppt

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TKR hit distribution (4)
Hit rate of each layer for charged events, where the primary track (the track the reconstruction program gives back first) is bent. original model new model

vrvs_2003-09-01_appendix.ppt

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# of reconstructed tracks (1)
original model
Charged events

new model

original model
Neutral events

new model

vrvs_2003-09-01_appendix.ppt

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# of reconstructed tracks (2)
Charged events The first tracks is straight

original model

new model

original model
Charged events The first track is bent

new model

vrvs_2003-09-01_appendix.ppt

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