1 / 6

Kaon back pointing

We improved the accuracy in the K extrapolation from one emisphere to the other. Kaon back pointing. The presence of a big De/dx tail ( or of a bad reconstructed momentum ) in the “handle” is signalled by a big impact parameter of the handle track when extrapolated to the IP.

herve
Download Presentation

Kaon back pointing

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. We improved the accuracy in the K extrapolation from one emisphere to the other Kaon back pointing The presence of a big De/dx tail ( or of a bad reconstructed momentum ) in the “handle” is signalled by a big impact parameter of the handle track when extrapolated to the IP Big Landau tail DE/DX on DC wall “handle” K Wrong momentum assigned to the other K Wrong curvature reconstructed

  2. K back pointing improvement |Dpt| f vs DR12 We use a cut on the radial and longitudinal distance of the K track from IP to recover a better resolution. To test it on data we plot the f momentum reconstructed from a couple of K versus the Kaons closest approach distance in r and z plane |Dpz| f vs DZ12 Dpf = pK2+ pK1 - pboost

  3. Dpf resolution improvement (Dpx)f No sel on K PCA (Dpx)f Sel on K PCA: Rmax = 1.5 cm Zmax = 2.0 cm

  4. Dpf resolution improvement 2 (Dpz)f No sel on K PCA (Dpz)f Sel on K PCA: Rmax = 1.5 cm Zmax = 2.0 cm

  5. K streaming vs dedx The aim is to modify the old algo 3 selection. This selection basically asks for a Kaon with right momentum and narrow PCA to IP. The background veto relies on raw hit hinfo and is not effective. Algo 3 is the most populated of the KPM stream We try to use the dedx info of the algo 3 Kaons to reject the background .. 2x2 sample #ADC sample 3x3 sample

  6. K streaming vs dedx 2 We compare the truncated mean for the algo 3 kaons (black) with that of the Kaons from algo 3 X tag (red) . The background pions are clearly visible ALGO 3 ALGO 3 and TAG

More Related