This shows you the differences between two versions of the page.
Next revision | Previous revision | ||
2017:groups:higgs:powhegpt [2017/07/19 08:32] robert.harlander created |
2017:groups:higgs:powhegpt [2017/11/20 12:18] (current) gudrun.heinrich |
||
---|---|---|---|
Line 1: | Line 1: | ||
- | ==== Large pT in POWHEG ==== | + | ===== Large pT in POWHEG ===== |
The issue is a significant hardening of the pT-spectrum after showering in POWHEG+Pythia8 for certain observables, even for non-zero values of the POWHEG damping factor (specific examples are gg->HH, see [[http://arxiv.org/abs/arXiv:1703.09252|arXiv:1703.09252]], or gg->H, see [[http://arxiv.org/abs/arXiv:1510.08850|arXiv:1510.08850]]). | The issue is a significant hardening of the pT-spectrum after showering in POWHEG+Pythia8 for certain observables, even for non-zero values of the POWHEG damping factor (specific examples are gg->HH, see [[http://arxiv.org/abs/arXiv:1703.09252|arXiv:1703.09252]], or gg->H, see [[http://arxiv.org/abs/arXiv:1510.08850|arXiv:1510.08850]]). | ||
Line 7: | Line 7: | ||
* Can one identify classes of observables where the effect is more prominent than in others? | * Can one identify classes of observables where the effect is more prominent than in others? | ||
* Is the effect specific to Pythia8, or is it observed also with Pythia6? | * Is the effect specific to Pythia8, or is it observed also with Pythia6? | ||
+ | Here are example plots {{2017:working_groups:sm:nlo_swr_hdamp_pthh_full_py6.pdf| hdamp=250}},{{2017:working_groups:sm:nlo_swr_pthh_full_py6.pdf| hdamp=infty}} from gg to HH which suggest that the effect is more pronounced with Pythia8 than with Pythia6. The plots are also in version 2 (journal version) of [[http://arxiv.org/abs/arXiv:1703.09252|arXiv:1703.09252]]. | ||
+ | |||
* Is the effect specific to POWHEG? | * Is the effect specific to POWHEG? | ||
* In [[http://arxiv.org/abs/arXiv:1510.08850|arXiv:1510.08850]], it was proposed to restrict the shower scale in the remnant events: is this legitimate for all observables? | * In [[http://arxiv.org/abs/arXiv:1510.08850|arXiv:1510.08850]], it was proposed to restrict the shower scale in the remnant events: is this legitimate for all observables? |