Difference between revisions of "JEF meeting Jul 13, 2015"

From GlueXWiki
Jump to: navigation, search
(→‎Agenda)
(→‎Minutes)
 
(8 intermediate revisions by the same user not shown)
Line 21: Line 21:
 
=Agenda=
 
=Agenda=
 
*[https://halldweb1.jlab.org/wiki/index.php/JEF_meeting_Jun_8,_2015#Agenda Task list] updates
 
*[https://halldweb1.jlab.org/wiki/index.php/JEF_meeting_Jun_8,_2015#Agenda Task list] updates
−
* η→3γ [Dave]
+
*[https://cnidlamp.jlab.org/RareEtaDecay/JDocDB/node/75 η→3γ] [Dave]
 
*[https://cnidlamp.jlab.org/RareEtaDecay/JDocDB/node/73# Size of PWO Insertion in FCAL-II]; [Liping]
 
*[https://cnidlamp.jlab.org/RareEtaDecay/JDocDB/node/73# Size of PWO Insertion in FCAL-II]; [Liping]
 
*[https://cnidlamp.jlab.org/RareEtaDecay/JDocDB/node/74# Tulin's talk at Patras Workshop]
 
*[https://cnidlamp.jlab.org/RareEtaDecay/JDocDB/node/74# Tulin's talk at Patras Workshop]
 +
 +
=Minutes=
 +
Attendees:  D. Dutta, L. Gan, M. Kamel, B. Karki, D. Mack, J. Roche, A. Somov, I. Strakovsky, S. Taylor, J. Stevens
 +
*Ilya has obtained the hybrid version of simulation/reconstruction code and will work on implementing the island code in this context. Next step is to make a factory for reconstruction of FCALI/II hits using reconstruction algorithm.
 +
** [https://halldweb.jlab.org/wiki/index.php/Gams_reconstruction Web page] with some details about Ilya's code
 +
*L. Gan gave a brief update about the insert.
 +
** A 60x60 cm^2 insert as a starting point appears to already part of the plan (radiation hardness)
 +
** Liping looked at effect of background for hybrid in the η→π0γγ channel due to η→3π0 as a function of insert size.
 +
*** Eγ=9-11.7 GeV; 3σ cuts for invariant mass and ΔE; parametrized position resolutions for lead glass and lead tungstate
 +
*** FOM=S/sqrt(B) increases with insert size:  120x120 cm^2 is about 2.5 times better than 60x60 cm^2
 +
* Liping reported that Eugene talked to Rolf regarding a small-scale (20 crystal) prototype. 
 +
** Hall C has already purchased several crystals -- arrange to share? 
 +
** Length has not been optimized yet (Primex length 18 cm vs 20 cm for Hall C; may need to make the face larger than Hall C's 2x2 cm^2 to accommodate shielding for PMT).
 +
** Sasha contacted Hamamatsu about PMTs -- no word yet?
 +
** DM suggested should get engineer to simulate magnetic shielding for expected conditions for insert
 +
** Calorimeter could in principle be moved further downstream...
 +
* Dave showed some slides regarding the impact of η(')→3γ based on some early work by Tarasov.
 +
** Probe C-violating/Parity conserving amplitudes.
 +
** Ratio of BR(3γ)/BR(2γ) depends on (unknown) loop mass -- if loop mass ~ m_π, a tight constraint can be obtained; if loop mass ~ m_ρ (for example) this decay is not interesting...
 +
** Should ask theorists to revisit η→3γ
 +
*Liping highlighted some slides from one of Tulin's workshop presentations on astrophysics.
 +
** Self-interacting dark matter may resolve some astrophysical discrepancies associated with cold collision-less dark matter  -- may have implications for our B-boson search?

Latest revision as of 09:19, 14 July 2015

Meeting time and location= 13:30 EST (JLab time) CC F326-327

=Connection instructions=

We are using BlueJeans Video/Audio conferencing. Our meeting ID number is 370588741. Click "Expand" for more details.

  • Make sure you have created a BlueJeans account via your JLab CUE account using this link:
  • If connecting via Web Browser: click this link (no passcode is needed):
  • If connecting via Phone: Dial one of the following numbers and then enter the meeting ID above and hit "#" or "##"
  • If connecting via Polycom unit:
    • Dial 199.48.152.152 or bjn.vc
    • Enter meeting ID above

Agenda

Minutes

Attendees: D. Dutta, L. Gan, M. Kamel, B. Karki, D. Mack, J. Roche, A. Somov, I. Strakovsky, S. Taylor, J. Stevens

  • Ilya has obtained the hybrid version of simulation/reconstruction code and will work on implementing the island code in this context. Next step is to make a factory for reconstruction of FCALI/II hits using reconstruction algorithm.
    • Web page with some details about Ilya's code
  • L. Gan gave a brief update about the insert.
    • A 60x60 cm^2 insert as a starting point appears to already part of the plan (radiation hardness)
    • Liping looked at effect of background for hybrid in the η→π0γγ channel due to η→3π0 as a function of insert size.
      • Eγ=9-11.7 GeV; 3σ cuts for invariant mass and ΔE; parametrized position resolutions for lead glass and lead tungstate
      • FOM=S/sqrt(B) increases with insert size: 120x120 cm^2 is about 2.5 times better than 60x60 cm^2
  • Liping reported that Eugene talked to Rolf regarding a small-scale (20 crystal) prototype.
    • Hall C has already purchased several crystals -- arrange to share?
    • Length has not been optimized yet (Primex length 18 cm vs 20 cm for Hall C; may need to make the face larger than Hall C's 2x2 cm^2 to accommodate shielding for PMT).
    • Sasha contacted Hamamatsu about PMTs -- no word yet?
    • DM suggested should get engineer to simulate magnetic shielding for expected conditions for insert
    • Calorimeter could in principle be moved further downstream...
  • Dave showed some slides regarding the impact of η(')→3γ based on some early work by Tarasov.
    • Probe C-violating/Parity conserving amplitudes.
    • Ratio of BR(3γ)/BR(2γ) depends on (unknown) loop mass -- if loop mass ~ m_π, a tight constraint can be obtained; if loop mass ~ m_ρ (for example) this decay is not interesting...
    • Should ask theorists to revisit η→3γ
  • Liping highlighted some slides from one of Tulin's workshop presentations on astrophysics.
    • Self-interacting dark matter may resolve some astrophysical discrepancies associated with cold collision-less dark matter -- may have implications for our B-boson search?
Retrieved from "https://halldweb.jlab.org/wiki/index.php?title=JEF_meeting_Jul_13,_2015&oldid=68623"