Methods for a blind analysis of isobar data collected by the STAR collaboration

Introduction: Stroke thrombectomy devices and the experience of neurointerventionists have improved significantly over the last few years making targeting distal occlusions such as of the M2 segment of the middle cerebral artery more feasible. We aimed to study the trend in the successful first pass (SFP) of M2 occlusions over time using the data from a contemporary multicenter registry. Methods: We reviewed the data from the Stroke Thrombectomy and Aneurysm Registry (STAR), which included data from 11 thrombectomy-capable stroke centers to identify stroke patients who underwent mechanical thrombectomy of M2 segment occlusion. SFP was defined by achieving modified Thrombolysis in Cerebral Infarction (mTICI) score≥2b with a single thrombectomy device pass. We analyzed the linear trendline of the rate of SFP over time. Then, we used a logistic regression model to assess predictors of SFP of M2 segment occlusion. Results: We included 401 patients who underwent stroke thrombectomy of M2 occlusion; median age was 71 (IQR 60-80), 212 (52.9%) were females, 174 (43.4%) were white, National Institute of Health stroke scale (NIHSS) was 14 (IQR 8-19), Alberta Stroke Program Early CT (ASPECT) score on presentation was 9 (IQR 7-10) and onset wot groin time was 287 (IQR 181-454). SFP was achieved in 118 (29.4%) patients (linear trendline over time is in Figure 1). Presenting after 2014 was an independent predictor of SFP (OR 1.9, 95% CI 1.1-3.2, P=0.019) after controlling for age, sex, NIHSS on presentation, intravenous alteplase (IV-tPA), and onset to groin time. Conclusion: SFP rate of M2 segment occlusion has increased after 2014 likely secondary the improvement in stroke thrombectomy devices and neurointerventionists experience.

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The STAR Collaboration

Journal of Physics G Nuclear and Particle Physics ◽

10.1088/0954-3899/31/6/m07 ◽

2005 ◽

Vol 31 (6) ◽

pp. S1231-S1233

Keyword(s):

Star Collaboration

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IDENTICAL MESON INTERFEROMETRY IN STAR EXPERIMENT

International Journal of Modern Physics E ◽

10.1142/s0218301307007179 ◽

2007 ◽

Vol 16 (07n08) ◽

pp. 1883-1889 ◽

Cited By ~ 1

Author(s):

◽

DEBASISH DAS

Keyword(s):

Particle Production ◽

Star Collaboration ◽

Heavy Ion ◽

Relativistic Heavy Ion Collisions ◽

Transverse Mass ◽

Particle Multiplicity ◽

Charged Particle Multiplicity ◽

Time Dynamics ◽

Ion Collisions ◽

Freeze Out

The influence of Bose–Einstein statistics on multi-particle production characterized for various systems and energies by the STAR collaboration provides interesting information about the space-time dynamics of relativistic heavy-ion collisions at RHIC. We present the centrality and transverse mass dependence measurements of the two-pion interferometry in Au + Au collisions at [Formula: see text] and Cu + Cu collisions at [Formula: see text] and 200 GeV. We compare the new data with previous STAR measurements from p + p , d + Au and Au + Au collisions at [Formula: see text]. In all systems and centralities, HBT radii decrease with transverse mass in a similar manner, which is qualitatively consistent with collective flow. The scaling of the apparent freeze-out volume with the number of participants and charged particle multiplicity is studied. Measurements of Au + Au collisions at same centralities and different energies yield different freeze-out volumes, which mean that N part is not a suitable scaling variable. The multiplicity scaling of the measured HBT radii is found to be independent of colliding system and collision energy.

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Study of the sign change of the Sivers function from STAR collaboration W/Z production data

Journal of High Energy Physics ◽

10.1007/jhep04(2017)046 ◽

2017 ◽

Vol 2017 (4) ◽

Cited By ~ 24

Author(s):

M. Anselmino ◽

M. Boglione ◽

U. D’Alesio ◽

F. Murgia ◽

A. Prokudin

Keyword(s):

Star Collaboration ◽

Production Data ◽

Sign Change ◽

Sivers Function

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Production of light flavored charged hadron in pp collisions at 900 GeV with hadron production models

Modern Physics Letters A ◽

10.1142/s0217732319501001 ◽

2019 ◽

Vol 34 (13) ◽

pp. 1950100 ◽

Cited By ~ 13

Author(s):

M. Ajaz ◽

M. Tufail ◽

Y. Ali

Keyword(s):

Transverse Momentum ◽

Entire Range ◽

Star Collaboration ◽

Hadron Production ◽

Charged Hadron ◽

Experimental Measurements ◽

Average Transverse Momentum ◽

Production Models ◽

200 Gev ◽

Small Rise

Differential yields of light flavored charged hadrons in [Formula: see text] collision at 0.9 TeV in the transverse momentum [Formula: see text] ranging from 0.1–2.5 GeV/c with pseudorapidity [Formula: see text] are presented here. The spectra obtained by Monte Carlo simulations with event generators — EPOS 1.99, EPOS-LHC, QGSJETII-04 and Sibyll2.3c — are compared with the ALICE measurements. For [Formula: see text] mesons, EPOS1.99, EPOS-LHC and QGSJETII-04 described the ALICE measurement very well almost in the entire [Formula: see text] range except QGSJETII-04 which underpredicts with [Formula: see text] below 0.4 GeV/c. The Sibyll2.3c model slightly overpredicts for [Formula: see text] GeV/c and underpredicts afterwards. For [Formula: see text] mesons, all models describe the experimental data qualitatively, except at high [Formula: see text], where the models slightly underpredict. The EPOS-LHC and QGSJETII-04 models, at low [Formula: see text], describe the distribution of the experimental measurements very well in both cases of protons and anti-protons, whereas the former underpredicts and the latter overpredicts at higher [Formula: see text]. The EPOS1.99 overpredicts at low [Formula: see text] below 1 GeV/c, whereas it reproduces the results well above it. Sibyll2.3c overpredicts the distribution over the entire range of [Formula: see text]. Models described the average transverse momentum [Formula: see text] of these hadron species as a function of their mass, showing small rise in the average [Formula: see text] with the mass of the particles. The same has been observed by the STAR collaboration with measurements in [Formula: see text] reactions at [Formula: see text] = 200 GeV and also in [Formula: see text] collisions at [Formula: see text] = 900 GeV.

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pT spectra of charged hadrons in proton–proton collisions at s = 200 GeV

Modern Physics Letters A ◽

10.1142/s0217732319501487 ◽

2019 ◽

Vol 34 (19) ◽

pp. 1950148 ◽

Cited By ~ 10

Author(s):

M. Ajaz ◽

Maryam

Keyword(s):

Transverse Momentum ◽

Star Collaboration ◽

Hadron Production ◽

Proton Proton ◽

Proton Collisions ◽

Production Models ◽

Momentum Spectra ◽

200 Gev ◽

Transverse Momentum Spectra ◽

Proton Proton Collisions

The transverse momentum spectra of [Formula: see text] mesons, protons and antiprotons produced in proton–proton collisions at 200 GeV with hadron production models are reported. Two tunes of EPOS (EPOS1.99 and EPOS-LHC), three tunes of QGSJET (QGSJETI, QGSJETII-03, QGSJETII-04), DPMJET and HIJING models are used to obtain the spectra. The results are compared with the measurements of STAR collaboration obtained at mid-rapidity of [Formula: see text] in [Formula: see text] range of [Formula: see text]. All models reproduce the ratios [Formula: see text] and [Formula: see text] at low [Formula: see text] but could not predict well at high [Formula: see text]. In addition, EPOS tunes and QGSJET tunes predict well the spectra of [Formula: see text] meson and the ratios [Formula: see text] and [Formula: see text] at low [Formula: see text]. The HIJING and the QGSJET (tune I only) could reproduce all the spectra and all the ratios at a satisfactory level of precision and were found good among the models considered in the current study at RHIC energy.

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Highlights from the STAR experiment

EPJ Web of Conferences ◽

10.1051/epjconf/201920401018 ◽

2019 ◽

Vol 204 ◽

pp. 01018

Author(s):

Alexey Aparin

Keyword(s):

Beam Energy ◽

Star Collaboration ◽

Fixed Target ◽

Directed Flow ◽

Decay Modes ◽

Charm Quarks ◽

Star Experiment ◽

The One ◽

Beam Energy Scan ◽

Program Show

We present an overview of the recent results obtained by the STAR Collaboration at RHIC.We report the beam energy dependence of directed flow of strange particles. These results support the assumption, that directed flow is formed before hadronization and observed particles are formed via coalescence of constituent quarks. First evidence of a non-zero directed flow of D0 meson is reported. We present the precision measurement of elliptic flow of D0 meson and the first measurement of Λc baryon in Au+Au collisions at $\rad{}{s_{NN} } = 200\,{\rm{GeV}}$, which suggests thermalization of charm quarks. We report results of global Λ polarization measurements in Au+Au collisions, together with the investigation of polarization dependence of centrality and transverse momentum pT. Results from the STAR fixed-target program show good agreement with previously obtained results. A precise measurement of the $_{{\rm{\Lambda }}}^{3} H$ lifetime is presented. Mesonic decay modes are used to reconstruct the $_{{\rm{\Lambda }}}^{3} H$ from Au+Au collisions. The measured lifetime is about 50% shorter than the one of a free Λ, indicating a strong hyperon-nucleon interaction in the hypernucleus system. Finally, we give an outlook to detector upgrades for the Beam Energy Scan phase II.

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