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Paper page: Inclusive jet cross-section in pp collisions at \sqrt{s} = 200 and 510 GeV

Updated on Mon, 2025-04-21 22:17. Originally created by veprbl on 2023-08-07 15:49.

Title

Inclusive jet cross-section in pp collisions at $\sqrt{s} = 200$ and 510 GeV

PAs

Elke Aschenauer, Zilong Chang, Renee Fatemi, Dmitry Kalinkin, Scott Wissink

Target Journal

Physical Review D

Abstract

Jets, collimated clusters of particles, produced in pp collisions at the Relativistic Heavy Ion Collider (RHIC) are dominated by gg and qg partonic processes. Therefore jet production in pp collisions allows us to directly probe the gluon parton distribution function (PDF) in the proton in a way complementary to deep inelastic scatterings. In this paper, we report the differential inclusive jet cross-sections as a function of jet transverse momentum, pT, and pseudo-rapidity, η, at center-of-mass energy $\sqrt{s} = 200$ and 510 GeV from pp collisions studied with the STAR detector. At mid-pseudorapidity, |η| < 0.9, the kinematic coverages of our data reach $0.07 < x_{\text{T}}{} = 2p_{\text{T}}{} / \sqrt{s} < 0.5$ and 0.03 < xT < 0.31 at $\sqrt{s} = 200$ and 510 GeV, respectively, where the explored gluon PDF is loosely constrained by the TeV-scale pp(p̄) colliders. The jet pT is corrected for underlying event contributions by applying an off-axis cone method. The inclusive jet cross sections are compared to the perturbative quantum chromodynamics calculations at the next-to-next-to-leading order with inputs from several recent PDF sets. These results will further constrain the gluon PDF, tune Monte Carlo generators, and provide critical reference data needed to study the quark-gluon plasma at STAR.

References

Past presentations

pp200:

pp510:

Figures

Jet spectra as a function of reconstructed detector jet pT from combined Jet Patch exclusive triggered sample. The spectra from the simulation are scaled to the sampled luminosities for each trigger during data taking. Left plot is for $\sqrt{s}=200$ GeV and right plot is for 510 GeV. Drop off for the bin at 19 GeV/c for 510 GeV occurs due to a large difference of the prescale factor between JP1 and JP2, and is well reproduced by the Monte Carlo simulation.
A comparison of the charge-separated fh distribution for track with momentum 2  < p< 3 GeV/c between data and simulation, where the data are samples from the 2012 510 GeV pp collisions. The reasons to separate by hadron charged signs are that K− has larger interaction cross section with the electro-magnetic calorimeter materials than K+, and that p̄ can annihilate with p from the Pb plates in the calorimeter.

$\frac{p_{\text{T};\text{detector}}}{p_{\text{T},\text{particle}}}$ at various particle jet pT bins from the embedding sample where the corresponding detector jets must satisfy the exclusive JP0 trigger for the lowest pT bin, exclusive JP1 for intermediate and exclusive JP2 for the highest pT. The exclusive trigger selections are based on the choice made in this analysis to avoid double counting among three jet patch triggered events with increasing thresholds. Left plot is for $\sqrt{s}=200$ GeV and right plot is for 510 GeV.
Hadronization correction factor at $\sqrt{s} = 200$ and 510 GeV. Error bars represent systematic uncertainty obtained from Perugia 2012 tune variations 374, 375, 376, 377 and 383 which are related to alternative values for hadronization parameters.
Jet cross-section predicted by Pythia 6 and Pythia 8 taken in a ratio to the present measurements at $\sqrt{s} = 200$ GeV (on the left) and at $\sqrt{s} = 510$ GeV (on the right).
Ratio of jet cross-section calculated from pQCD at NNLO with hadronization correction applied to cross-section from the present measurements at $\sqrt{s} = 200$ GeV (on the left) and at $\sqrt{s} = 510$ GeV (on the right). The NNLO PDFs include CT18 , MSHT20 , NNPDF4.0 and HEARPDF 2.0 .
$\frac{1}{2\pi}p^3_T\frac{d^2\sigma}{dp_Td\eta}$ vs. xT compared with NNLO pQCD calculations after hadronization corrections and Pythia 6 with STAR tune. The errors on the measured invariant jet cross sections are statistical uncertainties and transferred independently as the error of the invariant jet cross section ratio. The systematic uncertainties from the jet cross sections at $\sqrt{s} =$ 200 and 510 GeV are correlated, and not reflected in the errors of invariant jet cross section ratios.

Tables

Systematics: pp200

Systematic uncertainties in percentage for inclusive jet production cross section at $\sqrt{s}= 200$ GeV.
|η| < 0.5
Bin (GeV/c) Total(%) Energy scale(%) Track eff(%) Unfold(%)
6.9 – 8.2 17.2 16.0 2.1 3.3
8.2 – 9.7 25.3 24.5 1.3 5.6
9.7 – 11.5 12.3 9.5 2.4 5.2
11.5 – 13.6 17.0 15.7 1.5 5.7
13.6 – 16.1 10.1 8.7 2.2 3.9
16.1 – 19.0 11.0 8.8 2.4 4.4
19.0 – 22.5 12.9 12.0 2.5 3.5
22.5 – 26.6 8.6 7.4 2.3 3.9
26.6 – 31.4 21.3 20.6 3.4 2.7
31.4 – 37.2 9.6 8.8 0.8 3.4
37.2 – 44.0 25.5 23.0 5.4 7.6
44.0 – 52.0 20.3 18.8 3.7 6.5
0.5 < |η| < 0.9
Bin (GeV/c) Total(%) Energy scale(%) Track eff(%) Unfold(%)
6.9 – 8.2 18.9 17.0 1.7 4.2
8.2 – 9.7 22.3 21.0 1.8 7.3
9.7 – 11.5 16.2 12.8 2.0 8.1
11.5 – 13.6 14.4 12.7 1.7 6.1
13.6 – 16.1 9.2 7.2 2.4 4.0
16.1 – 19.0 9.7 8.9 2.5 3.0
19.0 – 22.5 11.3 10.5 1.9 2.8
22.5 – 26.6 11.7 11.3 2.9 2.5
26.6 – 31.4 11.5 10.9 2.7 3.2
31.4 – 37.2 15.0 14.1 3.9 4.4
37.2 – 44.0 23.1 21.7 1.0 7.6
44.0 – 52.0 55.7 51.8 4.6 13.5

Systematics: pp510

Systematic uncertainties in percentage for inclusive jet production cross section at $\sqrt{s}= 510$ GeV.
|η|< 0.5
Bin(GeV/c) Total(%) Energy scale(%) Track eff(%) Unfold(%)
8 – 10 9.8 7.3 1.4 6.3
10 – 13 6.9 4.5 1.1 5.1
13 – 17 7.4 4.8 3.0 4.7
17 – 21 9.5 7.0 4.1 4.9
21 – 26 5.8 3.3 1.7 4.4
26 – 32 8.4 5.9 3.1 5.1
32 – 39 10.8 8.5 4.4 5.0
39 – 47 12.1 9.8 5.1 4.9
47 – 57 15.6 12.7 6.6 6.3
57 – 68 23.9 19.7 9.7 9.5
68 – 80 28.4 22.7 11.0 13.0
0.5  < |η|< 0.9
Bin(GeV/c) Total(%) Energy scale(%) Track eff(%) Unfold(%)
8 – 10 10.5 8.5 0.6 6.2
10 – 13 7.0 4.9 0.8 5.0
13 – 17 7.5 4.9 3.3 4.5
17 – 21 9.9 7.3 4.4 5.0
21 – 26 5.4 2.7 1.5 4.5
26 – 32 9.1 6.7 3.6 5.1
32 – 39 12.0 9.5 4.8 5.6
39 – 47 13.5 11.2 5.5 5.3
47 – 57 16.4 13.7 6.6 6.2
57 – 68 27.1 21.6 9.9 13.0
68 – 80 28.4 24.2 10.9 10.3

Results: pp200

Double differential inclusive jet cross-section at $\sqrt{s} = 200$ GeV.
|η| < 0.5
(pT − ΔpTUE) (GeV/c) $\frac{\mathrm{d}\sigma^2}{\mathrm{d}p_{\text{T}}\mathrm{d}\eta} (\text{pb}/\text{GeV})$ ± stat.(%) ± syst. (%)
6.9 – 8.2 5.42 × 106 ± 0.4% ± 17.1%
8.2 – 9.7 1.95 × 106 ± 0.5% ± 25.4%
9.7 – 11.5 7.03 × 105 ± 0.5% ± 12.5%
11.5 – 13.6 2.53 × 105 ± 0.5% ± 17.3%
13.6 – 16.1 9.51 × 104 ± 0.6% ± 10.7%
16.1 – 19.0 3.14 × 104 ± 0.7% ± 8.8%
19.0 – 22.5 1.01 × 104 ± 1.0% ± 13.0%
22.5 – 26.6 3.06 × 103 ± 1.4% ± 9.9%
26.6 – 31.4 8.31 × 102 ± 2.3% ± 12.3%
31.4 – 37.2 2.05 × 102 ± 3.8% ± 12.9%
37.2 – 44.0 4.15 × 101 ± 7.3% ± 16.2%
44.0 – 52.0 5.59 × 100 ± 15.4% ± 26.4%
0.5 < |η| < 0.9
(pT − ΔpTUE) (GeV/c) $\frac{\mathrm{d}\sigma^2}{\mathrm{d}p_{\text{T}}\mathrm{d}\eta} (\text{pb}/\text{GeV})$ ± stat.(%) ± syst. (%)
6.9 – 8.2 4.84 × 106 ± 0.4% ± 19.1%
8.2 – 9.7 1.67 × 106 ± 0.6% ± 20.3%
9.7 – 11.5 6.54 × 105 ± 0.6% ± 19.4%
11.5 – 13.6 2.14 × 105 ± 0.7% ± 16.6%
13.6 – 16.1 7.99 × 104 ± 0.7% ± 9.9%
16.1 – 19.0 2.71 × 104 ± 1.0% ± 12.0%
19.0 – 22.5 7.96 × 103 ± 1.3% ± 9.8%
22.5 – 26.6 2.26 × 103 ± 2.0% ± 12.8%
26.6 – 31.4 5.25 × 102 ± 3.5% ± 10.5%
31.4 – 37.2 1.27 × 102 ± 5.7% ± 15.2%
37.2 – 44.0 1.82 × 101 ± 13.8% ± 17.9%
44.0 – 52.0 1.39 × 100 ± 43.5% ± 35.1%

Results: pp510

Double differential inclusive jet cross-section at $\sqrt{s} = 510$ GeV.
|η|< 0.5
(pT − ΔpTUE) (GeV/c) $\frac{\mathrm{d}\sigma^2}{\mathrm{d}p_{\text{T}}\mathrm{d}\eta} (\text{pb}/\text{GeV})$ ± stat.(%) ± syst. (%)
8 – 10 1.16×107 ± 0.2% ± 9.8 %
10 – 13 3.11×106 ± 0.1% ± 6.9 %
13 – 17 7.65×105 ± 0.2% ± 7.4 %
17 – 21 2.02×105 ± 0.4% ± 9.5 %
21 – 26 6.89×104 ± 0.3% ± 5.8 %
26 – 32 1.95×104 ± 0.4% ± 8.4 %
32 – 39 5.45×103 ± 0.7% ± 10.8 %
39 – 47 1.55×103 ± 1.1% ± 12.1 %
47 – 57 434 ± 1.5% ± 15.6 %
57 – 68 99.2 ± 4.0% ± 23.9 %
68 – 80 30.4 ± 4.1% ± 28.4 %
0.5 < |η|< 0.9
(pT − ΔpTUE) (GeV/c) $\frac{\mathrm{d}\sigma^2}{\mathrm{d}p_{\text{T}}\mathrm{d}\eta} (\text{pb}/\text{GeV})$ ± stat.(%) ± syst. (%)
8 – 10 1.02×107 ± 0.3% ± 10.5 %
10 – 13 2.83×106 ± 0.2% ± 7.0 %
13 – 17 6.99×105 ± 0.3% ± 7.5 %
17 – 21 1.98×105 ± 0.5% ± 9.9 %
21 – 26 5.87×104 ± 0.4% ± 5.4 %
26 – 32 1.75×104 ± 0.6% ± 9.1 %
32 – 39 5.01×103 ± 0.9% ± 12.0 %
39 – 47 1.38×103 ± 1.4% ± 13.5 %
47 – 57 349 ± 2.1% ± 16.4 %
57 – 68 93.4 ± 4.5% ± 27.1 %
68 – 80 18.1 ± 6.9% ± 28.4 %
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