pp reference

• Consider three types of pp references
  1. using heavy-flavour electrons cross section at pp 7 TeV measured at ATLAS
  2. using heavy-flavour muons cross section at pp 7 TeV measured at ATLAS
  3. using heavy-flavour muons cross section at pp 8 TeV measured at ALICE (2.5 < y < 4)
  4. using heavy-flavour muons cross section at pp 8 TeV measured at ALICE (2.5 < y < 2.8)
• At low pT (1.5 < pT < 4 GeV /c), reanalysed HFE cross section at pp 7 TeV is used in all patterns.
• In case of pattern 1 and 2, HFE cross section at pp 7 TeV measured at ALICE is used at 4 < pT < 8 GeV /c.

Summary of systematic uncertainty of pp references

• Uncertainty from FONLL scaling factor is included.

pp reference (using ATLAS 7 TeV electron data)

• 1.5 < pT < 4 GeV /c : reanalyzed pp cross section 7 TeV at ALICE (scaled to 8 TeV by using FONLL)
• 4 < pT < 8 GeV /c : pp cross section 7 TeV at ALICE (scaled to 8 TeV by using FONLL)
• pT > 8 GeV /c : pp cross section of HFE 7 TeV at ATLAS (scaled to 8 TeV by using FONLL)
  • ATLAS data is sum of electron and positron. So scaled by factor 2.
  • Corrected to invariant differential cross section.

• Strategy for calculating systematic uncertainty from FONLL
  https://arxiv.org/abs/1107.3243
• energy scaling
  • ε(enegy) = FONLL(8 TeV, |y|<0.6) / FONLL(7 TeV, |y|<0.6)
  • applided to all pp data
  • systematic uncertaincy ~ 1 %

• rapidity coverage scaling (ATLAS → ALICE)
  • ε(ATLASto-ALICE) = FONLL(7 TeV, |y|<0.6) / FONLL(7 TeV, |y|<2 excluding 1.37 to 1.52)
  • applided only to ATLAS data
  • systematic uncertaincy ~ 1 %

• boost scaling (|y|<0.6 → -1.065 < y < 0.135)
  • ε(boost) = FONLL(8 TeV, -1.065 < y < 0.135) / FONLL(8 TeV, |y|<0.6)
  • applided to all pp data
  • systematic uncertaincy « 1 %

FONLL / pp reference

• 1.5 < pT < 4 GeV /c : reanalyzed pp cross section 7 TeV at ALICE (scaled to 8 TeV by using FONLL)
  • data × ε(enegy) × ε(boost)
• 4 < pT < 8 GeV /c : pp cross section 7 TeV at ALICE (scaled to 8 TeV by using FONLL)
  • data × ε(enegy) × ε(boost)
• pT > 8 GeV /c : pp cross section of HFE 7 TeV at ATLAS (scaled to 8 TeV by using FONLL)
  • data × ε(ATLAStoALICE) × ε(enegy) × ε(boost)

Nuclear modification factor

pp reference (using ATLAS 7 TeV muon data)

FONLL / pp reference

• 1.5 < pT < 4 GeV /c : reanalyzed pp cross section 7 TeV at ALICE (scaled to 8 TeV by using FONLL)
• 4 < pT < 8 GeV /c : pp cross section 7 TeV at ALICE (scaled to 8 TeV by using FONLL)
• pT > 8 GeV /c : pp cross section of HFM 7 TeV at ATLAS (scaled to 8 TeV by using FONLL)
  • apply corrections of different rapidity range between ALICE (|y| < 0.6) and ATLAS (|y| < 2.0 excluding 1.37 to 1.52)

Nuclear modification factor

pp reference (using ALICE 8 TeV muon data (2.5 < y < 4))

• 1.5 < pT < 4 GeV /c : reanalyzed pp cross section 7 TeV at ALICE (scaled to 8 TeV by using FONLL)
• pT > 4 GeV /c : pp cross section of HFM 8 TeV at ALICE (2.5 < y < 4)
  • Corrected to invariant differential cross section.

FONLL scaling

• energy scaling
  • see above
  • applied only to ALICE electron data
• rapidity coverage scaling (2.5 < y < 4 → -0.6< y < 0.6)
  • ε(forward-to-mid) = FONLL(8 TeV, -0.6< y < 0.6) / FONLL(8 TeV, 2.5 < y < 4)
  • applided only to muon data
  • systematic uncertaincy ~ 3 %

• boost scaling (|y|<0.6 → -1.065 < y < 0.135)
  • see above
  • applided to all pp data

FONLL / pp reference

• 1.5 < pT < 4 GeV /c : reanalyzed pp cross section 7 TeV at ALICE (scaled to 8 TeV by using FONLL)
  • data × ε(enegy) × ε(boost)
• pT > 4 GeV /c : pp cross section of HFM 8 TeV at ALICE (2.5 < y < 4)
  • data × ε(forward-to-mid) × ε(boost)

Nuclear modification factor

• Note that muon cross section is up to 20 GeV /c (missing the last point 20-26 GeV /c)

pp reference (using ALICE 8 TeV muon data (2.5 < y < 2.8))

• 1.5 < pT < 4 GeV /c : reanalyzed pp cross section 7 TeV at ALICE (scaled to 8 TeV by using FONLL)
• pT > 4 GeV /c : pp cross section of HFM 8 TeV at ALICE (2.5 < y < 2.8)
  • Corrected to invariant differential cross section.

FONLL scaling

• energy scaling
  • see above
  • applied only to ALICE electron data
• rapidity coverage scaling (2.5 < y < 2.8 → -0.6< y < 0.6)
  • ε(forward-to-mid) = FONLL(8 TeV, -0.6< y < 0.6) / FONLL(8 TeV, 2.5 < y < 2.8)
  • applided only to muon data
  • systematic uncertaincy ~ 1 %

• boost scaling (|y|<0.6 → -1.065 < y < 0.135)
  • see above
  • applided to all pp data

FONLL / pp reference

• 1.5 < pT < 4 GeV /c : reanalyzed pp cross section 7 TeV at ALICE (scaled to 8 TeV by using FONLL)
  • data × ε(enegy) × ε(boost)
• pT > 4 GeV /c : pp cross section of HFM 8 TeV at ALICE (2.5 < y < 2.8)
  • data × ε(forward-to-mid) × ε(boost)

Nuclear modification factor

• Note that muon cross section is up to 20 GeV /c (missing the last point 20-26 GeV /c)

-- DaichiKawana - 2018-04-09