1 / 11

w and r ± sources of p 0 background in PRIMEX

w and r ± sources of p 0 background in PRIMEX. p 0 elasticity distribution observed in PRIMEX (crystal part of Hycal). Calculation of number of p 0 near the elastic peak is not enough. We have to know their spectrum to check how they affect fit which we are using to

xerxes
Download Presentation

w and r ± sources of p 0 background in PRIMEX

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. w and r± sources of p0 background in PRIMEX

  2. p0 elasticity distribution observed in PRIMEX (crystal part of Hycal) Calculation of number of p0 near the elastic peak is not enough. We have to know their spectrum to check how they affect fit which we are using to separate our elastic peak !

  3. The following sources of quasielastic p0s were studied: • Coherent w: g A -> w A • Incoherent w: g A -> w N A’ g A -> wD A’ • Incoherent r±: g A -> r± N A’ g A -> r±D A’ With consequent decays: w/r0 -> p0g; w -> p0p-p+; r± -> p0p±

  4. w/r decays kinematics:E(p0) / E(w/r) distribution

  5. t’ distributions for w and r production used in MC t’ = |t – tmin|

  6. production angle distributions for w and r used in MC

  7. cos(qGJ) distributions for w and r used in MC 1+x2 1-x2

  8. Distributions obtained from MC were scaled and subtracted from the data Scale factor for MC data: Kscale = FMC / Fdata FMC = Nevent NC / (L Br s) L – number of atoms per sq. unit Br – decay branching ratio s – production cross section

  9. p0 elasticity distribution observed (crystal part of Hycal) with simulated background from w and r+ - w and r+ - contribution r+ - only contribution

  10. p0 elasticity distribution with subtracted background from w and r+ - Elastic peak parameters improved

  11. dN/dq for original data and with background subtraction (on the level of gg invariant mass spectrum, bin by bin basis) original rad. width changes by ~ -0.8%; more calculations will be performed Subtracted part

More Related