Measurements of hadron production in $\pi^{+}$ + C and $\pi^{+}$ + Be interactions at 60 GeV/$c$

The NA61/SHINE collaboration Aduszkiewicz, A. ; Andronov, E.V. ; Antićić, T. ; et al.
Phys.Rev. D100 (2019) 112004, 2019.
Inspire Record 1754136 DOI 10.17182/hepdata.91220

Precise knowledge of hadron production rates in the generation of neutrino beams is necessary for accelerator-based neutrino experiments to achieve their physics goals. NA61/SHINE, a large-acceptance hadron spectrometer, has recorded hadron+nucleus interactions relevant to ongoing and future long-baseline neutrino experiments at Fermi National Accelerator Laboratory. This paper presents three analyses of interactions of 60 GeV/$c$ $\pi^+$ with thin, fixed carbon and beryllium targets. Integrated production and inelastic cross sections were measured for both of these reactions. In an analysis of strange, neutral hadron production, differential production multiplicities of $K^0_{S}$, $\Lambda$ and anti-$\Lambda$ were measured. Lastly, in an analysis of charged hadron production, differential production multiplicities of $\pi^+$, $\pi^-$, $K^+$, $K^-$ and protons were measured. These measurements will enable long-baseline neutrino experiments to better constrain predictions of their neutrino flux in order to achieve better precision on their neutrino cross section and oscillation measurements.

16 data tables

Doubly differential multiplicity measurements of produced pi+ from 60 GeV/c pi+ + C interactions. Statistical and systematic uncertainties are shown. Additionally, a normalization uncertainty of [-1.1%,+1.9%] applies to all of the measurements for this reaction.

Doubly differential multiplicity measurements of produced pi- from 60 GeV/c pi+ + C interactions. Statistical and systematic uncertainties are shown. Additionally, a normalization uncertainty of [-1.1%,+1.9%] applies to all of the measurements for this reaction.

Doubly differential multiplicity measurements of produced K+ from 60 GeV/c pi+ + C interactions. Statistical and systematic uncertainties are shown. Additionally, a normalization uncertainty of [-1.1%,+1.9%] applies to all of the measurements for this reaction.

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Measurement of $\phi$ Meson Production in p + p Interactions at 40, 80 and 158 GeV/c with the NA61/SHINE Spectrometer at the CERN SPS

The NA61/SHINE collaboration Aduszkiewicz, A. ; Andronov, E.V. ; Antićić, T. ; et al.
2019.
Inspire Record 1749613 DOI 10.17182/hepdata.93228

Results on $\phi$ meson production in inelastic p+p collisions at CERN SPS energies are presented. They are derived from data collected by the NA61/SHINE fixed target experiment, by means of invariant mass spectra fits in the $\phi \to K^+K^-$ decay channel. They include the first ever measured double differential spectra of $\phi$ mesons as a function of rapidity $y$ and transverse momentum $p_T$ for proton beam momenta of 80 GeV/c and 158 GeV/c, as well as single differential spectra of $y$ or $p_T$ for beam momentum of 40 GeV/c. The corresponding total $\phi$ yields per inelastic p+p event are obtained. These results are compared with existing data on $\phi$ meson production in p+p collisions. The comparison shows consistency but superior accuracy of the present measurements. The emission of $\phi$ mesons in p+p reactions is confronted with that occurring in Pb+Pb collisions, and the experimental results are compared with model predictions. It appears that none of the considered models can properly describe all the experimental observables.

17 data tables

Double differential multiplicity of $\phi$ mesons produced in minimum bias p+p collisions at beam momentum of 158 GeV/c, as a function of transverse momentum $p_T$ and rapidity $y$.

Double differential multiplicity of $\phi$ mesons produced in minimum bias p+p collisions at beam momentum of 80 GeV/c, as a function of transverse momentum $p_T$ and rapidity $y$.

Transverse momentum $p_T$ spectrum of $\phi$ mesons produced in minimum bias p+p collisions at beam momentum of 40 GeV/c, in a broad rapidity $y$ bin of (0, 1.5).

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Measurements of $\pi ^\pm $ , $K^\pm $ and proton double differential yields from the surface of the T2K replica target for incoming 31 GeV/c protons with the NA61/SHINE spectrometer at the CERN SPS

The NA61/SHINE collaboration Abgrall, N. ; Aduszkiewicz, A. ; Andronov, E.V. ; et al.
Eur.Phys.J. C79 (2019) 100, 2019.
Inspire Record 1687433 DOI 10.17182/hepdata.88360

Measurements of the $\pi^{\pm}$, $K^{\pm}$, and proton double differential yields emitted from the surface of the 90-cm-long carbon target (T2K replica) were performed for the incoming 31 GeV/c protons with the NA61/SHINE spectrometer at the CERN SPS using data collected during 2010 run. The double differential $\pi^{\pm}$ yields were measured with increased precision compared to the previously published NA61/SHINE results, while the $K^{\pm}$ and proton yields were obtained for the first time. A strategy for dealing with the dependence of the results on the incoming proton beam profile is proposed. The purpose of these measurements is to reduce significantly the (anti)neutrino flux uncertainty in the T2K long-baseline neutrino experiment by constraining the production of (anti)neutrino ancestors coming from the T2K target.

272 data tables

Double differential yiedls of positively charged pions emitted from the surface of the T2K replica target, in the polar angle range from 0 to 20 mrad and in the longitudinal range from 0 to 18cm, as a function of momentum. The normalization is per proton on target.

Double differential yiedls of positively charged pions emitted from the surface of the T2K replica target, in the polar angle range from 20 to 40 mrad and in the longitudinal range from 0 to 18cm, as a function of momentum. The normalization is per proton on target.

Double differential yiedls of positively charged pions emitted from the surface of the T2K replica target, in the polar angle range from 40 to 60 mrad and in the longitudinal range from 0 to 18cm, as a function of momentum. The normalization is per proton on target.

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Study of the process $e^+e^-\to\omega\eta\pi^0$ in the energy range $\sqrt{s} <2$ GeV with the SND detector

Achasov, M.N. ; Aulchenko, V.M. ; Barnyakov, A.Yu. ; et al.
Phys.Rev. D94 (2016) 032010, 2016.
Inspire Record 1471515 DOI 10.17182/hepdata.82577

The process e+e-→ωηπ0 is studied in the energy range 1.45–2.00 GeV using data with an integrated luminosity of 33  pb-1 accumulated by the SND detector at the e+e- collider VEPP-2000. The e+e-→ωηπ0 cross section is measured for the first time. The cross section has a threshold near 1.75 GeV. Its value is about 2 nb in the energy range 1.8–2.0 GeV. The dominant intermediate state for the process e+e-→ωηπ0 is found to be ωa0(980).

1 data table

The energy interval, integrated luminosity ($L$), number of selected events ($N$), estimated number of background events ($N_{bkg}$), detection efficiency for $e^+e^-\to\omega\eta\pi^0\to 7\gamma$ events ($\epsilon$), radiative correction ($\delta+1$), and $e^+e^-\to\omega\eta\pi^0$ Born cross section ($\sigma$). The shown cross-section errors are statistical. The systematic error is 4.2%. The 90% confidence level upper limits are listed for the first two energy intervals.


Study of the reaction $e^+e^- \to \pi^0\gamma$ with the SND detector at the VEPP-2M collider

The SND collaboration Achasov, M.N. ; Beloborodov, K.I. ; Berdyugin, A.V. ; et al.
Phys.Rev. D93 (2016) 092001, 2016.
Inspire Record 1418483 DOI 10.17182/hepdata.77047

The process e+e-→π0γ is studied with the SND detector at the VEPP-2M e+e- collider. The e+e-→π0γ cross section is measured in the center-of-mass energy range from 0.60 to 1.38 GeV. The cross section is well described by the vector meson dominance model. From the fit to the cross-section data we determine the branching fractions B(ρ→π0γ)=(4.20±0.52)×10-4, B(ω→π0γ)=(8.88±0.18)%, and B(ϕ→π0γ)=(1.367±0.072)×10-3, and the relative phase between the ρ and ω amplitudes φρ=(-12.7±4.5)°. Our data on the process e+e-→π0γ are the most accurate to date.

1 data table

The c.m.energy ($E$), integrated luminosity ($L$), detection efficiency ($\varepsilon$), number of selected signal events ($N_{\rm sig}$), radiative-correction factor ($1+\delta$), measured Born cross section ($\sigma$). For the cross section the first error is statistical, the second is systematic.


Measurement of $R_{\text{uds}}$ and $R$ between 3.12 and 3.72 GeV at the KEDR detector

Anashin, V.V. ; Aulchenko, V.M. ; Baldin, E.M. ; et al.
Phys.Lett. B753 (2016) 533-541, 2016.
Inspire Record 1397002 DOI 10.17182/hepdata.76727

Using the KEDR detector at the VEPP-4M e+e− collider, we have measured the values of Ruds and R at seven points of the center-of-mass energy between 3.12 and 3.72 GeV. The total achieved accuracy is about or better than 3.3% at most of energy points with a systematic uncertainty of about 2.1% . At the moment it is the most accurate measurement of R(s) in this energy range.

1 data table

Measured values of $R_{\rm{uds}}(s)$ and $R(s)$ with statistical and systematic uncertainties.


Measurement of the $K_L$ nuclear interaction length in the NaI(Tl) calorimeter

Achasov, M.N. ; Beloborodov, K.I. ; Berdyugin, A.V. ; et al.
JINST 10 (2015) P09006, 2015.
Inspire Record 1392011 DOI 10.17182/hepdata.69471

In the study of the reaction e(+)e(−)→ KSKL at the VEPP-2M e(+)e(−) collider with the SND detector the nuclear interaction length of KL meson in NaI(Tl) has been measured. Its value is found to be 30–50 cm in the KL momentum range 0.11–0.48 GeV/c. The results are compared with the values used in the simulation programs GEANT4 and UNIMOD.

1 data table

The energy interval ($\sqrt{s}$), integrated luminosity ($IL$), number of selected events ($N$), number of background events ($N_{\rm bkg}$), number of events with five or more photons ($N_{5\gamma}$, $N_{5\gamma,{\rm bkg}}$), and the measured $K_L$ nuclear interaction length in NaI(Tl) ($\lambda_{\rm int}$).


Measurement of the $e^+e^- \to \eta\pi^+\pi^-$ cross section in the center-of-mass energy range 1.22-2.00 GeV with the SND detector at the VEPP-2000 collider

The SND collaboration Aulchenko, V.M. ; Achasov, M.N. ; Barnyakov, A.Yu. ; et al.
Phys.Rev. D91 (2015) 052013, 2015.
Inspire Record 1332929 DOI 10.17182/hepdata.73176

<p>In the experiment with the SND detector at the VEPP-2000 <inline-formula><mml:math display="inline"><mml:msup><mml:mi>e</mml:mi><mml:mo>+</mml:mo></mml:msup><mml:msup><mml:mi>e</mml:mi><mml:mo>-</mml:mo></mml:msup></mml:math></inline-formula> collider the cross section for the process <inline-formula><mml:math display="inline"><mml:msup><mml:mi>e</mml:mi><mml:mo>+</mml:mo></mml:msup><mml:msup><mml:mi>e</mml:mi><mml:mo>-</mml:mo></mml:msup><mml:mo stretchy="false">→</mml:mo><mml:mi>η</mml:mi><mml:msup><mml:mi>π</mml:mi><mml:mo>+</mml:mo></mml:msup><mml:msup><mml:mi>π</mml:mi><mml:mo>-</mml:mo></mml:msup></mml:math></inline-formula> has been measured in the center-of-mass energy range from 1.22 to 2.00 GeV. Obtained results are in agreement with previous measurements and have better accuracy. The energy dependence of the <inline-formula><mml:math display="inline"><mml:mrow><mml:msup><mml:mrow><mml:mi>e</mml:mi></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msup><mml:msup><mml:mrow><mml:mi>e</mml:mi></mml:mrow><mml:mrow><mml:mo>-</mml:mo></mml:mrow></mml:msup><mml:mo stretchy="false">→</mml:mo><mml:mi>η</mml:mi><mml:msup><mml:mrow><mml:mi>π</mml:mi></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msup><mml:msup><mml:mrow><mml:mi>π</mml:mi></mml:mrow><mml:mrow><mml:mo>-</mml:mo></mml:mrow></mml:msup></mml:mrow></mml:math></inline-formula> cross section has been fitted with the vector-meson dominance model. From this fit the product of the branching fractions <inline-formula><mml:math display="inline"><mml:mrow><mml:mi>B</mml:mi><mml:mo stretchy="false">(</mml:mo><mml:mi>ρ</mml:mi><mml:mo stretchy="false">(</mml:mo><mml:mn>1450</mml:mn><mml:mo stretchy="false">)</mml:mo><mml:mo stretchy="false">→</mml:mo><mml:mi>η</mml:mi><mml:msup><mml:mrow><mml:mi>π</mml:mi></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msup><mml:msup><mml:mrow><mml:mi>π</mml:mi></mml:mrow><mml:mrow><mml:mo>-</mml:mo></mml:mrow></mml:msup><mml:mo stretchy="false">)</mml:mo><mml:mi>B</mml:mi><mml:mo stretchy="false">(</mml:mo><mml:mi>ρ</mml:mi><mml:mo stretchy="false">(</mml:mo><mml:mn>1450</mml:mn><mml:mo stretchy="false">)</mml:mo><mml:mo stretchy="false">→</mml:mo><mml:msup><mml:mrow><mml:mi>e</mml:mi></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msup><mml:msup><mml:mrow><mml:mi>e</mml:mi></mml:mrow><mml:mrow><mml:mo>-</mml:mo></mml:mrow></mml:msup><mml:mo stretchy="false">)</mml:mo></mml:mrow></mml:math></inline-formula> has been extracted and compared with the same products for <inline-formula><mml:math display="inline"><mml:mrow><mml:mi>ρ</mml:mi><mml:mo stretchy="false">(</mml:mo><mml:mn>1450</mml:mn><mml:mo stretchy="false">)</mml:mo><mml:mo stretchy="false">→</mml:mo><mml:mi>ω</mml:mi><mml:msup><mml:mrow><mml:mi>π</mml:mi></mml:mrow><mml:mrow><mml:mn>0</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:math></inline-formula> and <inline-formula><mml:math display="inline"><mml:mrow><mml:mi>ρ</mml:mi><mml:mo stretchy="false">(</mml:mo><mml:mn>1450</mml:mn><mml:mo stretchy="false">)</mml:mo><mml:mo stretchy="false">→</mml:mo><mml:msup><mml:mrow><mml:mi>π</mml:mi></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msup><mml:msup><mml:mrow><mml:mi>π</mml:mi></mml:mrow><mml:mrow><mml:mo>-</mml:mo></mml:mrow></mml:msup></mml:mrow></mml:math></inline-formula> decays. The obtained cross section data have been also used to test the conservation of vector current hypothesis.</p>

1 data table

The c.m. energy ($\sqrt{s}$), integrated luminosity ($L$), detection efficiency ($\varepsilon$), number of selected signal events ($N$), radiative-correction factor ($1 + \delta$), measured $e^+e^- \to \eta \pi^+\pi^-$ Born cross section ($\sigma_B$). For the number of events and cross section the statistical error is quoted. The systematic uncertainty on the cross section is 8.3% at $\sqrt{s}<1.45$ GeV, 5.0% at $1.45<\sqrt{s}<1.60$ GeV, and 7.8% at $\sqrt{s}>1.60$ GeV.


Study of the process $e^+e^-\to n\bar{n}$ at the VEPP-2000 $e^+e^-$ collider with the SND detector

Achasov, M.N. ; Barnyakov, A.Yu. ; Beloborodov, K.I. ; et al.
Phys.Rev. D90 (2014) 112007, 2014.
Inspire Record 1321689 DOI 10.17182/hepdata.71416

<p>The process <inline-formula><mml:math display="inline"><mml:msup><mml:mi>e</mml:mi><mml:mo>+</mml:mo></mml:msup><mml:msup><mml:mi>e</mml:mi><mml:mo>-</mml:mo></mml:msup><mml:mo stretchy="false">→</mml:mo><mml:mi>n</mml:mi><mml:mover accent="true"><mml:mi>n</mml:mi><mml:mo accent="true" stretchy="false">¯</mml:mo></mml:mover></mml:math></inline-formula> has been studied at the VEPP-2000 <inline-formula><mml:math display="inline"><mml:msup><mml:mi>e</mml:mi><mml:mo>+</mml:mo></mml:msup><mml:msup><mml:mi>e</mml:mi><mml:mo>-</mml:mo></mml:msup></mml:math></inline-formula> collider with the SND detector in the energy range from threshold up to 2 GeV. As a result of the experiment, the <inline-formula><mml:math display="inline"><mml:msup><mml:mi>e</mml:mi><mml:mo>+</mml:mo></mml:msup><mml:msup><mml:mi>e</mml:mi><mml:mo>-</mml:mo></mml:msup><mml:mo stretchy="false">→</mml:mo><mml:mi>n</mml:mi><mml:mover accent="true"><mml:mi>n</mml:mi><mml:mo accent="true" stretchy="false">¯</mml:mo></mml:mover></mml:math></inline-formula> cross section and effective neutron form factor have been measured.</p>

2 data tables

The $e^+e^-\to n\bar{n}$ cross section ($\sigma_{n\bar{n}}$) and neutron effective form factor ($F_n$) measured in 2011. The quoted errors are statistical. The systematic error is 17$\%$ for the cross section and 9$\%$ for the form factor.

The $e^+e^-\to n\bar{n}$ cross section ($\sigma_{n\bar{n}}$) and neutron effective form factor ($F_n$) measured in 2012. The quoted errors are statistical. The systematic error is 17$\%$ for the cross section and 9$\%$ for the form factor. NOTE: corrected an apparent typo in paper for second-last data point (1990 $\to$ 1960) to make the numbers consistent with the plot in Figure 9.


Search for neutrino emission from relic dark matter in the Sun with the Baikal NT200 detector

The Baikal collaboration Avrorin, A.D. ; Avrorin, A.V. ; Aynutdinov, V.M. ; et al.
Astropart.Phys. 62 (2015) 12-20, 2015.
Inspire Record 1296058 DOI 10.17182/hepdata.64126
6 data tables

Process: DM DM --> BOTTOM BOTTOMBAR. Half-cone angle GAMMA, 90% upper limit N(SIGNAL) on the number of signal events, the muon flux PHI(MU), the dark matter annihilation rate in the Sun GAMMA(ANN), the dark matter-proton spin-dependent SIG(SD) and spin-independent SIG(SI) scattering cross sections and neutrino flux PHI(NU).

Process: DM DM --> TAU+ TAU-. Half-cone angle GAMMA, 90% upper limit N(SIGNAL) on the number of signal events, the muon flux PHI(MU), the dark matter annihilation rate in the Sun GAMMA(ANN), the dark matter-proton spin-dependent SIG(SD) and spin-independent SIG(SI) scattering cross sections and neutrino flux PHI(NU).

Process: DM DM --> W+ W-. Half-cone angle GAMMA, 90% upper limit N(SIGNAL) on the number of signal events, the muon flux PHI(MU), the dark matter annihilation rate in the Sun GAMMA(ANN), the dark matter-proton spin-dependent SIG(SD) and spin-independent SIG(SI) scattering cross sections and neutrino flux PHI(NU).

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Study of the process $e^+e^-\to\eta\gamma$ in the center-of-mass energy range 1.07--2.00 GeV

Achasov, M.N. ; Aulchenko, V.M. ; Barnyakov, A.Yu. ; et al.
Phys.Rev. D90 (2014) 032002, 2014.
Inspire Record 1275333 DOI 10.17182/hepdata.62279
2 data tables

The energy interval and E+ E- --> ETA GAMMA Born cross section(SIG). The first error in the cross section is statistical, the second systematic. For the last two energy intervals, the upper limits at the 90 PCT confidence level are listed for the cross section.

The fitted values of the cross sections at the resonance peaks.


Study of $e^+e^- \to \omega\pi^0 \to \pi^0\pi^0\gamma$ in the energy range $1.05-2.00$ GeV with SND

Achasov, M.N. ; Aulchenko, V.M. ; Barnyakov, A.Yu. ; et al.
Phys.Rev. D88 (2013) 054013, 2013.
Inspire Record 1224801 DOI 10.17182/hepdata.62287

The cross section for the process e+e- --> omega pi0 --> pi0 pi0 gamma has been measured in the energy range 1.05--2.00 GeV. The experiment has been performed at the e+e- collider VEPP-2000 with the SND detector. The measured e+e- --> omega pi0 cross section above 1.4 GeV is the most accurate to date. Below 1.4 GeV our data are in good agreement with the previous SND and CMD-2 measurements. Data on the e+e- --> omega pi0 cross section are well described by the VMD model with two excited rho-like states. From the measured cross section we have extracted the gamma^* --> omega pi0 transition form factor. It has been found that the VDM model cannot describe simultaneously our data and data obtained from the omega --> pi0 mu+ mu- decay. We have also tested CVC hypothesis comparing our results on the e+e- --> omega pi0 cross section with data on the tau- --> omega pi- nu_{tau} decay.

1 data table

The c.m. energy(E) and measured Born cross section(SIG). For the cross section, the first error is statistical, the second is systematic.


System size and energy dependence of near-side di-hadron correlations

The STAR collaboration Agakishiev, G. ; Aggarwal, M.M. ; Ahammed, Z. ; et al.
Phys.Rev. C85 (2012) 014903, 2012.
Inspire Record 943192 DOI 10.17182/hepdata.77720

Two-particle azimuthal ($\Delta\phi$) and pseudorapidity ($\Delta\eta$) correlations using a trigger particle with large transverse momentum ($p_T$) in $d$+Au, Cu+Cu and Au+Au collisions at $\sqrt{s_{{NN}}}$ =\xspace 62.4 GeV and 200~GeV from the STAR experiment at RHIC are presented. The \ns correlation is separated into a jet-like component, narrow in both $\Delta\phi$ and $\Delta\eta$, and the ridge, narrow in $\Delta\phi$ but broad in $\Delta\eta$. Both components are studied as a function of collision centrality, and the jet-like correlation is studied as a function of the trigger and associated $p_T$. The behavior of the jet-like component is remarkably consistent for different collision systems, suggesting it is produced by fragmentation. The width of the jet-like correlation is found to increase with the system size. The ridge, previously observed in Au+Au collisions at $\sqrt{s_{{NN}}}$ = 200 GeV, is also found in Cu+Cu collisions and in collisions at $\sqrt{s_{{NN}}}$ =\xspace 62.4 GeV, but is found to be substantially smaller at $\sqrt{s_{{NN}}}$ =\xspace 62.4 GeV than at $\sqrt{s_{{NN}}}$ = 200 GeV for the same average number of participants ($ \langle N_{\mathrm{part}}\rangle$). Measurements of the ridge are compared to models.

40 data tables

Parameterizations of the transverse momentum dependence of the reconstruction efficiency of charged particles in the TPC in various collision systems, energies and centrality bins for the track selection cuts used in this analysis.

The raw correlation in $\Delta\eta$ for di-hadron correlations for 3 $<$ $p_T^{trigger}$ $<$ 6 GeV/$c$ and 1.5 GeV/$c$ $<$ $p_T^{associated}$ $<$ $p_T^{trigger}$ for 0-12% central \Au collisions for $|\Delta\phi|<$ 0.78 before and after the track merging correction is applied. The data have been reflected about $\Delta\eta$=0.

Sample correlations in $\Delta\eta$ ($|\Delta\phi|<$ 0.78) for 3 $<$ $p_T^{trigger}$ $<$ 6 GeV/$c$ and 1.5 GeV/$c$ $<$ $p_T^{associated}$ $<$ $p_T^{trigger}$ for 0-60% Cu+Cu at $\sqrt{s_{NN}}$ = 62.4 GeV, 0-80% Au+Au at $\sqrt{s_{NN}}$ = 62.4 GeV, 0-95% $d$+Au at $\sqrt{s_{NN}}$ = 200 GeV, 0-60% Cu+Cu at $\sqrt{s_{NN}}$ = 200 GeV, 40-80% Au+Au at $\sqrt{s_{NN}}$ = 200 GeV, and 0-12% central Au+Au at $\sqrt{s_{NN}}$ = 200 GeV. The data are averaged between positive and negative $\Delta\eta$. 5% systematic uncertainty due to track reconstruction efficiency not listed below.

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Observation of the antimatter helium-4 nucleus

The STAR collaboration Agakishiev, H. ; Aggarwal, M.M. ; Ahammed, Z. ; et al.
Nature 473 (2011) 353, 2011.
Inspire Record 893021 DOI 10.17182/hepdata.58495
1 data table

Differential invariant yields of (anti)baryons evaluated at pT/B =0.875 GeV/c, in central 200 GeV Au+Au collisions.


Study of Jet Shapes in Inclusive Jet Production in $pp$ Collisions at $\sqrt{s}=7$ TeV using the ATLAS Detector

The ATLAS collaboration Aad, G. ; Abbott, B. ; Abdallah, J. ; et al.
Phys.Rev. D83 (2011) 052003, 2011.
Inspire Record 882984 DOI 10.17182/hepdata.63511

Jet shapes have been measured in inclusive jet production in proton-proton collisions at sqrt(s) = 7 TeV using 3 pb^{-1} of data recorded by the ATLAS experiment at the LHC. Jets are reconstructed using the anti-kt algorithm with transverse momentum 30 GeV < pT < 600 GeV and rapidity in the region |y| < 2.8. The data are corrected for detector effects and compared to several leading-order QCD matrix elements plus parton shower Monte Carlo predictions, including different sets of parameters tuned to model fragmentation processes and underlying event contributions in the final state. The measured jets become narrower with increasing jet transverse momentum and the jet shapes present a moderate jet rapidity dependence. Within QCD, the data test a variety of perturbative and non-perturbative effects. In particular, the data show sensitivity to the details of the parton shower, fragmentation, and underlying event models in the Monte Carlo generators. For an appropriate choice of the parameters used in these models, the data are well described.

124 data tables

Measured Differential Jet Shape RHO as a function of r for jet transverse momentum from 30 to 40 GeV and absolute values of the jet rapidity from 0 to 2.8.

Measured Differential Jet Shape RHO as a function of r for jet transverse momentum from 40 to 60 GeV and absolute values of the jet rapidity from 0 to 2.8.

Measured Differential Jet Shape RHO as a function of r for jet transverse momentum from 60 to 80 GeV and absolute values of the jet rapidity from 0 to 2.8.

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Charged-particle multiplicities in pp interactions measured with the ATLAS detector at the LHC

The ATLAS collaboration Aad, G. ; Abbott, B. ; Abdallah, J. ; et al.
New J.Phys. 13 (2011) 053033, 2011.
Inspire Record 882098 DOI 10.17182/hepdata.57077

Measurements are presented from proton-proton collisions at centre-of-mass energies of sqrt(s) = 0.9, 2.36 and 7 TeV recorded with the ATLAS detector at the LHC. Events were collected using a single-arm minimum-bias trigger. The charged-particle multiplicity, its dependence on transverse momentum and pseudorapidity and the relationship between the mean transverse momentum and charged-particle multiplicity are measured. Measurements in different regions of phase-space are shown, providing diffraction-reduced measurements as well as more inclusive ones. The observed distributions are corrected to well-defined phase-space regions, using model-independent corrections. The results are compared to each other and to various Monte Carlo models, including a new AMBT1 PYTHIA 6 tune. In all the kinematic regions considered, the particle multiplicities are higher than predicted by the Monte Carlo models. The central charged-particle multiplicity per event and unit of pseudorapidity, for tracks with pT >100 MeV, is measured to be 3.483 +- 0.009 (stat) +- 0.106 (syst) at sqrt(s) = 0.9 TeV and 5.630 +- 0.003 (stat) +- 0.169 (syst) at sqrt(s) = 7 TeV.

41 data tables

Charged-particle multiplicities in proton-proton collisions at a centre-of mass energy of 900 GeV as a function of pseudorapidity for events with the number of charged particles >=1 having transverse momentum >500 MeV and absolute(pseudorapidity) <2.5.

Charged-particle multiplicities in proton-proton collisions at a centre-of mass energy of 2360 GeV as a function of pseudorapidity for events with the number of charged particles >=1 having transverse momentum >500 MeV and absolute(pseudorapidity) <2.5.

Charged-particle multiplicities in proton-proton collisions at a centre-of mass energy of 7000 GeV as a function of pseudorapidity for events with the number of charged particles >=1 having transverse momentum >500 MeV and absolute(pseudorapidity) <2.5.

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Measurement of the inclusive isolated prompt photon cross section in $pp$ collisions at $\sqrt{s}=7$ TeV with the ATLAS detector

The ATLAS collaboration Aad, G. ; Abbott, B. ; Abdallah, J. ; et al.
Phys.Rev. D83 (2011) 052005, 2011.
Inspire Record 882463 DOI 10.17182/hepdata.57465

A measurement of the cross section for the inclusive production of isolated prompt photons in pp collisions at a centre-of-mass energy sqrt(s) = 7TeV is presented. The measurement covers the pseudorapidity ranges |eta|<1.37 and 1.52<|eta|<1.81 in the transverse energy range 15 < E_T <100 GeV. The results are based on an integrated luminosity of 880 nb-1, collected with the ATLAS detector at the Large Hadron Collider. Photon candidates are identified by combining information from the calorimeters and from the inner tracker. Residual background in the selected sample is estimated from data based on the observed distribution of the transverse isolation energy in a narrow cone around the photon candidate. The results are compared to predictions from next-to-leading order perturbative QCD calculations.

3 data tables

The measured prompt photon cross section as a function of transverse energy for the |pseudorapidity| range < 0.6.

The measured prompt photon cross section as a function of transverse energy for the |pseudorapidity| range 0.6 to 1.37.

The measured prompt photon cross section as a function of transverse energy for the |pseudorapidity| range 1.52 to 1.81.


Measurement of the $W \to \ell\nu$ and $Z/\gamma^* \to \ell\ell$ production cross sections in proton-proton collisions at $\sqrt{s} = 7$ TeV with the ATLAS detector

The ATLAS collaboration Aad, G. ; Abbott, B. ; Abdallah, J. ; et al.
JHEP 1012 (2010) 060, 2010.
Inspire Record 872570 DOI 10.17182/hepdata.56744

First measurements of the W -> lnu and Z/gamma* -> ll (l = e, mu) production cross sections in proton-proton collisions at sqrt(s) = 7 TeV are presented using data recorded by the ATLAS experiment at the LHC. The results are based on 2250 W -> lnu and 179 Z/gamma* -> ll candidate events selected from a data set corresponding to an integrated luminosity of approximately 320 nb-1. The measured total W and Z/gamma*-boson production cross sections times the respective leptonic branching ratios for the combined electron and muon channels are $\stotW$ * BR(W -> lnu) = 9.96 +- 0.23(stat) +- 0.50(syst) +- 1.10(lumi) nb and $\stotZg$ * BR(Z/gamma* -> ll) = 0.82 +- 0.06(stat) +- 0.05(syst) +- 0.09(lumi) nb (within the invariant mass window 66 < m_ll < 116 GeV). The W/Z cross-section ratio is measured to be 11.7 +- 0.9(stat) +- 0.4(syst). In addition, measurements of the W+ and W- production cross sections and of the lepton charge asymmetry are reported. Theoretical predictions based on NNLO QCD calculations are found to agree with the measurements.

35 data tables

Measured fiducial cross section times leptonic branching ratio for W+ production in the W+ -> e+ nu final state.

Measured fiducial cross section times leptonic branching ratio for W- production in the W- -> e- nubar final state.

Measured fiducial cross section times leptonic branching ratio for W+/- production in the combined W+ -> e+ nu and W- -> e- nubar final state.

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Measurement of inclusive jet and dijet cross sections in proton-proton collisions at 7 TeV centre-of-mass energy with the ATLAS detector

The ATLAS collaboration Aad, G. ; Abbott, B. ; Abdallah, J. ; et al.
Eur.Phys.J. C71 (2011) 1512, 2011.
Inspire Record 871366 DOI 10.17182/hepdata.56004

Jet cross sections have been measured for the first time in proton-proton collisions at a centre-of-mass energy of 7 TeV using the ATLAS detector. The measurement uses an integrated luminosity of 17 nb-1 recorded at the Large Hadron Collider. The anti-kt algorithm is used to identify jets, with two jet resolution parameters, R = 0.4 and 0.6. The dominant uncertainty comes from the jet energy scale, which is determined to within 7% for central jets above 60 GeV transverse momentum. Inclusive single-jet differential cross sections are presented as functions of jet transverse momentum and rapidity. Dijet cross sections are presented as functions of dijet mass and the angular variable $\chi$. The results are compared to expectations based on next-to-leading-order QCD, which agree with the data, providing a validation of the theory in a new kinematic regime.

26 data tables

Inclusive jet double-differential cross sections in the |rapidity| range 0 to 0.3, using a jet resolution R value of 0.4. The three (sys) errors are respectively, the Absolute JES, the Unfolding and the Luminosity uncertainties.

Inclusive jet double-differential cross sections in the |rapidity| range 0.3 to 0.8, using a jet resolution R value of 0.4. The three (sys) errors are respectively, the Absolute JES, the Unfolding and the Luminosity uncertainties.

Inclusive jet double-differential cross sections in the |rapidity| range 0.8 to 1.2, using a jet resolution R value of 0.4. The three (sys) errors are respectively, the Absolute JES, the Unfolding and the Luminosity uncertainties.

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Search for quark contact interactions in dijet angular distributions in $pp$ collisions at $\sqrt{s}=7$ TeV measured with the ATLAS detector

The ATLAS collaboration Aad, G. ; Abbott, B. ; Abdallah, J. ; et al.
Phys.Lett. B694 (2011) 327-345, 2011.
Inspire Record 871487 DOI 10.17182/hepdata.57022

Dijet angular distributions from the first LHC pp collisions at center-of-mass energy sqrt(s) = 7 TeV have been measured with the ATLAS detector. The dataset used for this analysis represents an integrated luminosity of 3.1 pb-1. Dijet $\chi$ distributions and centrality ratios have been measured up to dijet masses of 2.8 TeV, and found to be in good agreement with Standard Model predictions. Analysis of the $\chi$ distributions excludes quark contact interactions with a compositeness scale $\Lambda$ below 3.4 TeV, at 95% confidence level, significantly exceeding previous limits.

5 data tables

CHI distribution for mass bin 340 to 520 GeV.

CHI distribution for mass bin 520 to 800 GeV.