Difference between revisions of "Spring 2017 Analysis Launch Cuts"

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* For a given DNeutralShower, it must at least have a shower energy of 100 MeV/c.  
 
* For a given DNeutralShower, it must at least have a shower energy of 100 MeV/c.  
 
* For neutral showers in the BCAL, they must have hits in at least 2 cells.  
 
* For neutral showers in the BCAL, they must have hits in at least 2 cells.  
 +
 +
== Timing Cuts ==
 +
* Timing cuts are applied only on the system with the best timing information available, in the order: BCAL/TOF/FCAL/SC.  In other words, if a track has a hit in the TOF, then no cut is applied on the FCAL or SC time. 
 +
* Note that some hypotheses may not have a hit in any system and thus survive all of these cuts.
 +
* Also, even if the SC is the best-available detector, no cut is placed on the timing if the track has been matched to more than one SC hit, UNLESS it's the only track in the combo.
 +
** This is because the SC timing is not really good enough for PID over such a short flight distance, so the cut is primarily used to reject tracks from other beam bunches or ghost tracks.
 +
* Also, all kaons are cut that:
 +
** Do not have a hit in one of these timing detectors, AND
 +
** Do not have enough hits in the CDC to compute dE/dx
 +
** This is because their background is huge already, without letting these combos through.
 +
{| border="1" cellpadding="2" align="left" valign="top" style="text-align:center;"
 +
!width="50"| PID
 +
!width="150"| BCAL/RF Δt (ns)
 +
!width="150"| TOF/RF Δt (ns)
 +
!width="150"| FCAL/RF Δt (ns)
 +
!width="150"| SC/RF Δt (ns)
 +
|-
 +
! γ
 +
| ±1.5 || NA || ±2.5 || NA
 +
|-
 +
! e<sup>+</sup>
 +
| ±1.0 || ±2.5 || ±2.5 || ±2.0
 +
|-
 +
! e<sup>-</sup>
 +
| ±1.0 || ±2.5 || ±2.5 || ±2.0
 +
|-
 +
! &mu;<sup>+</sup>
 +
| ±1.0 || ±2.5 || ±2.5 || ±2.0
 +
|-
 +
! &mu;<sup>-</sup>
 +
| ±1.0 || ±2.5 || ±2.5 || ±2.0
 +
|-
 +
! &pi;<sup>+</sup>
 +
| ±1.0 || ±0.5 || ±2.0 || ±2.0
 +
|-
 +
! &pi;<sup>-</sup>
 +
| ±1.0 || ±0.5 || ±2.0 || ±2.0
 +
|-
 +
! K<sup>+</sup>
 +
| ±0.75 || ±2.0 || ±2.5 || ±2.0
 +
|-
 +
! K<sup>-</sup>
 +
| ±0.75 || ±2.0 || ±2.5 || ±2.0
 +
|-
 +
! p
 +
| ±1.0 || ±0.6 || ±2.0 || ±2.0
 +
|-
 +
! p&#773;
 +
| ±1.0 || ±0.6 || ±2.0 || ±2.0
 +
|}
 +
<br style="clear:both;"/>
 +
 +
== Track Energy Cuts ==
 +
 +
{| border="1" cellpadding="2" align="left" valign="top" style="text-align:center;"
 +
!width="50"| PID
 +
!width="300"| CDC dE/dx (keV/cm)
 +
!width="300"| FDC dE/dx (keV/cm)
 +
!width="300"| SC dE/dx (MeV/cm)
 +
!width="300"| TOF dE/dx (MeV/cm)
 +
!width="200"| BCAL Shower_E/Track_p (c)
 +
!width="200"| FCAL Shower_E/Track_p (c)
 +
|-
 +
! p
 +
| dE/dx > e^(-3.93024*p + 3.0) + 1.0  || None || None || None || None || None
 +
|-
 +
! p&#773;
 +
| dE/dx > e^(-3.93024*p + 3.0) + 1.0 || None || None || None || None || None
 +
|-
 +
! &pi;<sup>+</sup>
 +
| dE/dx < e^(-6.0*p + 2.80149) + 2.55 || None || None || None || None || None
 +
|-
 +
! &pi;<sup>-</sup>
 +
| dE/dx < e^(-6.0*p + 2.80149) + 2.55 || None || None || None || None || None
 +
|-
 +
! K<sup>+</sup>
 +
| dE/dx < e^(-6.0*p + 2.80149) + 2.55 || None || None || None || None || None
 +
|-
 +
! K<sup>-</sup>
 +
| dE/dx < e^(-6.0*p + 2.80149) + 2.55 || None || None || None || None || None
 +
|-
 +
! e<sup>+</sup>
 +
| dE/dx < 5.5 || dE/dx < 3.5 || None || None || None || None
 +
|-
 +
! e<sup>-</sup>
 +
| dE/dx < 5.5 || dE/dx < 3.5 || None || None || None || None
 +
|}
 +
<br style="clear:both;"/>
  
 
== Mass Cuts ==
 
== Mass Cuts ==
Line 106: Line 194:
 
! &Lambda;<sub>c</sub>
 
! &Lambda;<sub>c</sub>
 
| 2.0 < IM < 2.6 || None
 
| 2.0 < IM < 2.6 || None
−
|}
 
−
<br style="clear:both;"/>
 
−
 
−
== Timing Cuts ==
 
−
* Timing cuts are applied only on the system with the best timing information available, in the order: BCAL/TOF/FCAL/SC.  In other words, if a track has a hit in the TOF, then no cut is applied on the FCAL or SC time. 
 
−
* Note that some hypotheses may not have a hit in any system and thus survive all of these cuts.
 
−
* Also, even if the SC is the best-available detector, no cut is placed on the timing if the track has been matched to more than one SC hit, UNLESS it's the only track in the combo.
 
−
** This is because the SC timing is not really good enough for PID over such a short flight distance, so the cut is primarily used to reject tracks from other beam bunches or ghost tracks.
 
−
* Also, all kaons are cut that:
 
−
** Do not have a hit in one of these timing detectors, AND
 
−
** Do not have enough hits in the CDC to compute dE/dx
 
−
** This is because their background is huge already, without letting these combos through.
 
−
{| border="1" cellpadding="2" align="left" valign="top" style="text-align:center;"
 
−
!width="50"| PID
 
−
!width="150"| BCAL/RF &Delta;t (ns)
 
−
!width="150"| TOF/RF &Delta;t (ns)
 
−
!width="150"| FCAL/RF &Delta;t (ns)
 
−
!width="150"| SC/RF &Delta;t (ns)
 
−
|-
 
−
! &gamma;
 
−
| ±1.5 || NA || ±2.5 || NA
 
−
|-
 
−
! e<sup>+</sup>
 
−
| ±1.0 || ±2.5 || ±2.5 || ±2.0
 
−
|-
 
−
! e<sup>-</sup>
 
−
| ±1.0 || ±2.5 || ±2.5 || ±2.0
 
−
|-
 
−
! &mu;<sup>+</sup>
 
−
| ±1.0 || ±2.5 || ±2.5 || ±2.0
 
−
|-
 
−
! &mu;<sup>-</sup>
 
−
| ±1.0 || ±2.5 || ±2.5 || ±2.0
 
−
|-
 
−
! &pi;<sup>+</sup>
 
−
| ±1.0 || ±0.5 || ±2.0 || ±2.0
 
−
|-
 
−
! &pi;<sup>-</sup>
 
−
| ±1.0 || ±0.5 || ±2.0 || ±2.0
 
−
|-
 
−
! K<sup>+</sup>
 
−
| ±0.75 || ±2.0 || ±2.5 || ±2.0
 
−
|-
 
−
! K<sup>-</sup>
 
−
| ±0.75 || ±2.0 || ±2.5 || ±2.0
 
−
|-
 
−
! p
 
−
| ±1.0 || ±0.6 || ±2.0 || ±2.0
 
−
|-
 
−
! p&#773;
 
−
| ±1.0 || ±0.6 || ±2.0 || ±2.0
 
−
|}
 
−
<br style="clear:both;"/>
 
−
 
−
== Track Energy Cuts ==
 
−
 
−
{| border="1" cellpadding="2" align="left" valign="top" style="text-align:center;"
 
−
!width="50"| PID
 
−
!width="300"| CDC dE/dx (keV/cm)
 
−
!width="300"| FDC dE/dx (keV/cm)
 
−
!width="300"| SC dE/dx (MeV/cm)
 
−
!width="300"| TOF dE/dx (MeV/cm)
 
−
!width="200"| BCAL Shower_E/Track_p (c)
 
−
!width="200"| FCAL Shower_E/Track_p (c)
 
−
|-
 
−
! p
 
−
| dE/dx > e^(-3.93024*p + 3.0) + 1.0  || None || None || None || None || None
 
−
|-
 
−
! p&#773;
 
−
| dE/dx > e^(-3.93024*p + 3.0) + 1.0 || None || None || None || None || None
 
−
|-
 
−
! &pi;<sup>+</sup>
 
−
| dE/dx < e^(-6.0*p + 2.80149) + 2.55 || None || None || None || None || None
 
−
|-
 
−
! &pi;<sup>-</sup>
 
−
| dE/dx < e^(-6.0*p + 2.80149) + 2.55 || None || None || None || None || None
 
−
|-
 
−
! K<sup>+</sup>
 
−
| dE/dx < e^(-6.0*p + 2.80149) + 2.55 || None || None || None || None || None
 
−
|-
 
−
! K<sup>-</sup>
 
−
| dE/dx < e^(-6.0*p + 2.80149) + 2.55 || None || None || None || None || None
 
−
|-
 
−
! e<sup>+</sup>
 
−
| dE/dx < 5.5 || dE/dx < 3.5 || None || None || None || None
 
−
|-
 
−
! e<sup>-</sup>
 
−
| dE/dx < 5.5 || dE/dx < 3.5 || None || None || None || None
 
 
|}
 
|}
 
<br style="clear:both;"/>
 
<br style="clear:both;"/>

Revision as of 13:57, 28 July 2017

PreSelect Cuts

  • For a given DChargedTrack, at least one hypothesis must have a hit in either: BCAL/FCAL/TOF/SC.
  • For a given DNeutralShower, it must at least have a shower energy of 100 MeV/c.
  • For neutral showers in the BCAL, they must have hits in at least 2 cells.

Timing Cuts

  • Timing cuts are applied only on the system with the best timing information available, in the order: BCAL/TOF/FCAL/SC. In other words, if a track has a hit in the TOF, then no cut is applied on the FCAL or SC time.
  • Note that some hypotheses may not have a hit in any system and thus survive all of these cuts.
  • Also, even if the SC is the best-available detector, no cut is placed on the timing if the track has been matched to more than one SC hit, UNLESS it's the only track in the combo.
    • This is because the SC timing is not really good enough for PID over such a short flight distance, so the cut is primarily used to reject tracks from other beam bunches or ghost tracks.
  • Also, all kaons are cut that:
    • Do not have a hit in one of these timing detectors, AND
    • Do not have enough hits in the CDC to compute dE/dx
    • This is because their background is huge already, without letting these combos through.
PID BCAL/RF Δt (ns) TOF/RF Δt (ns) FCAL/RF Δt (ns) SC/RF Δt (ns)
γ ±1.5 NA ±2.5 NA
e+ ±1.0 ±2.5 ±2.5 ±2.0
e- ±1.0 ±2.5 ±2.5 ±2.0
μ+ ±1.0 ±2.5 ±2.5 ±2.0
μ- ±1.0 ±2.5 ±2.5 ±2.0
π+ ±1.0 ±0.5 ±2.0 ±2.0
π- ±1.0 ±0.5 ±2.0 ±2.0
K+ ±0.75 ±2.0 ±2.5 ±2.0
K- ±0.75 ±2.0 ±2.5 ±2.0
p ±1.0 ±0.6 ±2.0 ±2.0
p̅ ±1.0 ±0.6 ±2.0 ±2.0


Track Energy Cuts

PID CDC dE/dx (keV/cm) FDC dE/dx (keV/cm) SC dE/dx (MeV/cm) TOF dE/dx (MeV/cm) BCAL Shower_E/Track_p (c) FCAL Shower_E/Track_p (c)
p dE/dx > e^(-3.93024*p + 3.0) + 1.0 None None None None None
p̅ dE/dx > e^(-3.93024*p + 3.0) + 1.0 None None None None None
π+ dE/dx < e^(-6.0*p + 2.80149) + 2.55 None None None None None
π- dE/dx < e^(-6.0*p + 2.80149) + 2.55 None None None None None
K+ dE/dx < e^(-6.0*p + 2.80149) + 2.55 None None None None None
K- dE/dx < e^(-6.0*p + 2.80149) + 2.55 None None None None None
e+ dE/dx < 5.5 dE/dx < 3.5 None None None None
e- dE/dx < 5.5 dE/dx < 3.5 None None None None


Mass Cuts

  • Note that if there are no particles missing, there is also a cut on the missing energy: -3.0 < Missing Energy (GeV) < 3.0
  • Detected Particles
PID Invariant Mass (GeV/c2) Missing Mass2 (GeV/c2)2
None NA -0.1 < MM2 < 0.1
γ NA -0.1 < MM2 < 0.1
e+ NA None
e- NA None
π- None -1.0 < MM2 < 1.0
π+ None -1.0 < MM2 < 1.0
K+ None None
K- None None
p NA -0.5 < MM2 < 4.41
p̅ NA -0.5 < MM2 < 4.41
n None -0.5 < MM2 < 4.41


  • Decaying Mesons
PID Invariant Mass (GeV/c2) Missing Mass2 (GeV/c2)2
π0 0.08 < IM < 0.19 -1.0 < MM2 < 1.0
KS 0.3 < IM < 0.7 None
η 0.4 < IM < 0.7 None
η' 0.6 < IM < 1.3 None
φ 0.8 < IM < 1.2 None
D0 1.8 < IM < 1.92 None
J/ψ None None


  • Decaying Baryons
PID Invariant Mass (GeV/c2) Missing Mass2 (GeV/c2)2
Λ 1.0 < IM < 1.2 None
Σ0 1.1 < IM < 1.3 None
Σ+ 1.1 < IM < 1.3 None
Σ- 1.1 < IM < 1.3 None
Ξ0 1.1 < IM < 1.5 None
Ξ- 1.1 < IM < 1.5 None
Ω- None None
Λc 2.0 < IM < 2.6 None


Kinematic Fit

  • If a kinematic fit has been performed, it must have converged.
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