HonexComb meeting #3

Tuesday 31 Mar 2020, 15:00 → 18:00 Europe/Zurich

53/R-044 (CERN)

Attendendance up to 50 people.

 

Comments to the talk of Gian-Michele, Jiayin (total charm cross-section):
• Slide 8, Anton Andronic: dsigma/dy and dsigma/dpT is as important as the pt- and y-integrated cross-section
• Slide 8, Johanna Stachel: start with dsigma/dy and then find a good extrapolation function, dsigma/dy is the basic quantity which should be addressed first
• Slide 8, Francesco Prino: pt-differential requires an extra step from the FF, because the momentum of the c-quark is different (it is an extra step)
• Slide 8, Johanna Stachel: first combine pT-spectra across experiments in a given rapidity interval, this gives dsigma/dy and then one obtains sigma.
• Slide 8, pbm: for total charm cross-section, FF is not needed if all charmed hadrons are measured over a large enough rapidity interval 
• Slide 8, Raph: one goal would be a legacy paper with all charm measurements that go into this.
• Slide 8, Johanna: LHC data is extremely valuable because forward and mid rapidity are available
• Slide 8: Francesco Prino: Baryon measurements at forward rapidity would be crucial.
• Slide 9:
-> LHCb data Lambda_c/D0 on ratios is not published (only integrated cross-sections are available) with systematics that is canceled.
-> Pietro says that it was provided by LHCb Physics Coordinator for ALICE plot in private communication => it would be good to have this officially published=> Jiayin and Giulia looking into that, Pietro to provide information on the analyst involved
• Slide 9 Pietro: pt-dependence is dominated by lowest accessible rapidity interval, interesting to address if this data is newly looked at by LHCb
• Francesco Prino: proposal to establish across experiments a common strategy how to extrapolate to zero pT.
• Pietro Antonioli: define a procedure to find fragmentation fractions that are pt-dependent
• Gian-Michele: produce a summary charm paper as intermediate step and total charm cross-section as derived quantity
• Raph: strong coordination with the heavy quark work package coordinated by Giuseppe Bruno
• Giuseppe Bruno: maybe we want to go back to older (lower energy data) with updated knowledge from LHC; some of these older data is already in HepData

15:00 → 15:10 Welcome

Speakers: Alexander Philipp Kalweit (CERN), Giulia Manca (Universita` degli studi di Cagliari and INFN, Cagliari, IT), Iwona Grabowska-Bold (AGH University of Science and Technology (PL)), Raphael Granier De Cassagnac (Centre National de la Recherche Scientifique (FR))

2020.03.31.HONEXCOMB.pdf

15:10 → 15:40 Towards a charm total cross-section

Speakers: Gian Michele Innocenti (CERN), Jiayin Sun (Tsinghua University)

TotalCharmCrossSection.pdf