Difference between revisions of "Mattione Update 06252012"
From GlueXWiki
(→Analysis Overview) |
|||
| (12 intermediate revisions by the same user not shown) | |||
| Line 4: | Line 4: | ||
*** φ → K<sup>+</sup>, K<sup>-</sup> | *** φ → K<sup>+</sup>, K<sup>-</sup> | ||
* Final State: p, π<sup>+</sup>, π<sup>-</sup>, K<sup>+</sup>, K<sup>-</sup> | * Final State: p, π<sup>+</sup>, π<sup>-</sup>, K<sup>+</sup>, K<sup>-</sup> | ||
| − | * Events Generated using genr8 with: 9 GeV Photons, Γ<sub>Y(2175)</sub> = 61 MeV/c<sup>2</sup>, t-slope = 5.0, 50.0 < Vertex-Z (cm) < 80.0 | + | * ~530,000 Events Generated using genr8 with: 9 GeV Photons, Γ<sub>Y(2175)</sub> = 61 MeV/c<sup>2</sup>, t-slope = 5.0, 50.0 < Vertex-Z (cm) < 80.0 |
| + | * No background generated (all background is from combinatorics) | ||
== Analysis Overview == | == Analysis Overview == | ||
| Line 10: | Line 11: | ||
** e.g. If a q = + track has PID FOM > 1% for both the π<sup>+</sup> & K<sup>+</sup>: allow both combinations (DO NOT take the best FOM as true!) | ** e.g. If a q = + track has PID FOM > 1% for both the π<sup>+</sup> & K<sup>+</sup>: allow both combinations (DO NOT take the best FOM as true!) | ||
* The analysis (cuts/histing/kinfits) is then performed on each possible track combination (events are only cut if every one of their track combinations is cut): | * The analysis (cuts/histing/kinfits) is then performed on each possible track combination (events are only cut if every one of their track combinations is cut): | ||
| + | ** Require the detection of at least 2+ and 2- tracks (proton is treated as missing) | ||
** Require the combined FOM for PID (π<sup>+</sup>, π<sup>-</sup>, K<sup>+</sup>, K<sup>-</sup>) be > 1% | ** Require the combined FOM for PID (π<sup>+</sup>, π<sup>-</sup>, K<sup>+</sup>, K<sup>-</sup>) be > 1% | ||
** Place very loose cuts on the φ invariant mass (0.8 - 1.3) and p missing mass (0.5 - 1.4): reduces # of bogus track combinations to save time / cleanup histograms | ** Place very loose cuts on the φ invariant mass (0.8 - 1.3) and p missing mass (0.5 - 1.4): reduces # of bogus track combinations to save time / cleanup histograms | ||
| Line 40: | Line 42: | ||
== Initial Mass Peaks == | == Initial Mass Peaks == | ||
| − | * | + | * Initial Mass Peaks |
| − | [[Image:Mattione_Update_06252012_Mass_Phi.png|left| | + | {| class="wikitable" |
| − | + | | [[Image:Mattione_Update_06252012_Mass_Phi.png|thumb|left|400px|φ Invariant Mass]] | |
| − | + | | [[Image:Mattione_Update_06252012_Mass_Proton.png|thumb|left|400px|Proton Missing Mass]] | |
| − | + | | [[Image:Mattione_Update_06252012_Mass_Y2175.png|thumb|left|400px|Y(2175) Invariant Mass]] | |
| − | [[Image:Mattione_Update_06252012_Mass_Proton.png|left| | + | |} |
| − | + | ||
| − | + | ||
| − | + | ||
| − | [[Image:Mattione_Update_06252012_Mass_Y2175.png|left| | + | |
<br style="clear:both;"/> | <br style="clear:both;"/> | ||
| Line 87: | Line 85: | ||
! π<sup>-</sup> | ! π<sup>-</sup> | ||
| [[Image:Mattione_Update_06252012_Pull_PiMinusPx.png|left|350px]] || [[Image:Mattione_Update_06252012_Pull_PiMinusPy.png|left|350px]] || [[Image:Mattione_Update_06252012_Pull_PiMinusPz.png|left|350px]] | | [[Image:Mattione_Update_06252012_Pull_PiMinusPx.png|left|350px]] || [[Image:Mattione_Update_06252012_Pull_PiMinusPy.png|left|350px]] || [[Image:Mattione_Update_06252012_Pull_PiMinusPz.png|left|350px]] | ||
| + | |} | ||
| + | <br style="clear:both;"/> | ||
| + | |||
| + | == Final Mass Peaks == | ||
| + | * Final Mass Peaks | ||
| + | ** The Y(2175) Invariant Mass is calculated using the kinematic fit values of the track 3-momenta. | ||
| + | ** The Y(2175) Invariant Mass is fit to Breit-Wigner over a quadratic background (I couldn't get the Voigtian fits to converge), and has Γ = ~80 MeV/c<sup>2</sup> (as opposed to the generated Γ = 61 MeV/<sup>2</sup>) | ||
| + | * ~18.9 % of all events remaining | ||
| + | {| class="wikitable" | ||
| + | | [[Image:Mattione_Update_06252012_Mass_FinalPhi.png|thumb|left|400px|φ Invariant Mass]] | ||
| + | | [[Image:Mattione_Update_06252012_Mass_FinalProton.png|thumb|left|400px|Proton Missing Mass]] | ||
| + | | [[Image:Mattione_Update_06252012_Mass_FinalY2175.png|thumb|left|400px|Y(2175) Invariant Mass]] | ||
| + | |} | ||
| + | <br style="clear:both;"/> | ||
| + | |||
| + | == Track P & PID Fraction vs. p == | ||
| + | |||
| + | * Track P & PID Fraction vs. p | ||
| + | {| border="1" cellpadding="2" align="left" valign="top" style="text-align:center;" | ||
| + | !width="50"| Track | ||
| + | !width="350"| Thrown Track p | ||
| + | !width="350"| Final Track p | ||
| + | !width="350"| PID % vs p | ||
| + | |- | ||
| + | ! K<sup>+</sup> | ||
| + | | [[Image:Mattione_Update_06252012_ThrownP_KPlus.png|left|350px]] || [[Image:Mattione_Update_06252012_ComboP_KPlus.png|left|350px]] || [[Image:Mattione_Update_06252012_PIDFractionVsP_KPlus.png|left|350px]] | ||
| + | |- | ||
| + | ! K<sup>-</sup> | ||
| + | | [[Image:Mattione_Update_06252012_ThrownP_KMinus.png|left|350px]] || [[Image:Mattione_Update_06252012_ComboP_KMinus.png|left|350px]] || [[Image:Mattione_Update_06252012_PIDFractionVsP_KMinus.png|left|350px]] | ||
| + | |- | ||
| + | ! π<sup>+</sup> | ||
| + | | [[Image:Mattione_Update_06252012_ThrownP_PiPlus.png|left|350px]] || [[Image:Mattione_Update_06252012_ComboP_PiPlus.png|left|350px]] || [[Image:Mattione_Update_06252012_PIDFractionVsP_PiPlus.png|left|350px]] | ||
| + | |- | ||
| + | ! π<sup>-</sup> | ||
| + | | [[Image:Mattione_Update_06252012_ThrownP_PiMinus.png|left|350px]] || [[Image:Mattione_Update_06252012_ComboP_PiMinus.png|left|350px]] || [[Image:Mattione_Update_06252012_PIDFractionVsP_PiMinus.png|left|350px]] | ||
|} | |} | ||
<br style="clear:both;"/> | <br style="clear:both;"/> | ||
Latest revision as of 14:21, 25 June 2012
Contents
Reaction
- γ p → Y(2175), p
- Y(2175) → π+, π-, φ
- φ → K+, K-
- Y(2175) → π+, π-, φ
- Final State: p, π+, π-, K+, K-
- ~530,000 Events Generated using genr8 with: 9 GeV Photons, ΓY(2175) = 61 MeV/c2, t-slope = 5.0, 50.0 < Vertex-Z (cm) < 80.0
- No background generated (all background is from combinatorics)
Analysis Overview
- For each q = +/- particle in the reaction, all detected q = +/- tracks are tested as to whether or not they are that particle
- e.g. If a q = + track has PID FOM > 1% for both the π+ & K+: allow both combinations (DO NOT take the best FOM as true!)
- The analysis (cuts/histing/kinfits) is then performed on each possible track combination (events are only cut if every one of their track combinations is cut):
- Require the detection of at least 2+ and 2- tracks (proton is treated as missing)
- Require the combined FOM for PID (π+, π-, K+, K-) be > 1%
- Place very loose cuts on the φ invariant mass (0.8 - 1.3) and p missing mass (0.5 - 1.4): reduces # of bogus track combinations to save time / cleanup histograms
- Kinematic Fit: 4-momentum conservation: p missing mass, φ invariant mass
- Require that the confidence level from the kinematic fit be > 1%
Thrown Track Parameters
- p vs θ
 |
 |
|
 |
 |
 |
PID
- PID FOM
 |
 |
 |
 |
Initial Mass Peaks
- Initial Mass Peaks
Kinematic Fitting Plots
- Confidence Level
- Confidence Level vs. Mass
 |
 |
- Pulls (Confidence Level Cut at 10% for histogramming)
- μ's = ~0.0, σ's = ~1.08
| Track | px Pull | py Pull | pz Pull |
|---|---|---|---|
| γ |  | ||
| K+ |  |
 |
 |
| K- |  |
 |
 |
| π+ |  |
 |
 |
| π- |  |
 |
 |
Final Mass Peaks
- Final Mass Peaks
- The Y(2175) Invariant Mass is calculated using the kinematic fit values of the track 3-momenta.
- The Y(2175) Invariant Mass is fit to Breit-Wigner over a quadratic background (I couldn't get the Voigtian fits to converge), and has Γ = ~80 MeV/c2 (as opposed to the generated Γ = 61 MeV/2)
- ~18.9 % of all events remaining
Track P & PID Fraction vs. p
- Track P & PID Fraction vs. p
| Track | Thrown Track p | Final Track p | PID % vs p |
|---|---|---|---|
| K+ |  |
 |
 |
| K- |  |
 |
 |
| π+ |  |
 |
 |
| π- |  |
 |
 |
