共查询到20条相似文献,搜索用时 15 毫秒
1.
Aamodt K Abelev B Quintana AA Adamová D Adare AM Aggarwal MM Rinella GA Agocs AG Salazar SA Ahammed Z Masoodi AA Ahmad N Ahn SU Akindinov A Aleksandrov D Alessandro B Molina RA Alici A Alkin A Aviña EA Alt T Altini V Altinpinar S Altsybeev I Andrei C Andronic A Anguelov V Anson C Antičić T Antinori F Antonioli P Aphecetche L Appelshäuser H Arbor N Arcelli S Arend A Armesto N Arnaldi R Aronsson T Arsene IC Asryan A Augustinus A Averbeck R Awes TC Aystö J Azmi MD Bach M Badalà A Baek YW 《Physical review letters》2010,105(25):252301
The first measurement of the charged-particle multiplicity density at midrapidity in Pb-Pb collisions at a center-of-mass energy per nucleon pair √ S NN = 2.76 TeV is presented. For an event sample corresponding to the most central 5% of the hadronic cross section, the pseudorapidity density of primary charged particles at midrapidity is 1584 ± 4(stat) ± 76(syst), which corresponds to 8.3 ± 0.4(syst) per participating nucleon pair. This represents an increase of about a factor 1.9 relative to pp collisions at similar collision energies, and about a factor 2.2 to central Au-Au collisions at √ S NN = 2.76 TeV. This measurement provides the first experimental constraint for models of nucleus-nucleus collisions at LHC energies. 相似文献
2.
Aamodt K Abelev B Quintana AA Adamová D Adare AM Aggarwal MM Rinella GA Agocs AG Salazar SA Ahammed Z Masoodi AA Ahmad N Ahn SU Akindinov A Aleksandrov D Alessandro B Molina RA Alici A Alkin A Aviña EA Alt T Altini V Altinpinar S Altsybeev I Andrei C Andronic A Anguelov V Anson C Antičić T Antinori F Antonioli P Aphecetche L Appelshäuser H Arbor N Arcelli S Arend A Armesto N Arnaldi R Aronsson T Arsene IC Asryan A Augustinus A Averbeck R Awes TC Aystö J Azmi MD Bach M Badalà A Baek YW 《Physical review letters》2010,105(25):252302
We report the first measurement of charged particle elliptic flow in Pb-Pb collisions at sqrt[S(NN)] =2.76 TeV with the ALICE detector at the CERN Large Hadron Collider. The measurement is performed in the central pseudorapidity region (|η|<0.8) and transverse momentum range 0.2
相似文献
3.
Aad G Abbott B Abdallah J Abdelalim AA Abdesselam A Abdinov O Abi B Abolins M Abramowicz H Abreu H Acerbi E Acharya BS Ackers M Adams DL Addy TN Adelman J Aderholz M Adomeit S Adragna P Adye T Aefsky S Aguilar-Saavedra JA Aharrouche M Ahlen SP Ahles F Ahmad A Ahsan M Aielli G Akdogan T Akesson TP Akimoto G Akimov AV Alam MS Alam MA Albrand S Aleksa M Aleksandrov IN Aleppo M Alessandria F Alexa C Alexander G Alexandre G Alexopoulos T Alhroob M Aliev M Alimonti G Alison J Aliyev M Allport PP 《Physical review letters》2010,105(25):252303
By using the ATLAS detector, observations have been made of a centrality-dependent dijet asymmetry in the collisions of lead ions at the Large Hadron Collider. In a sample of lead-lead events with a per-nucleon center of mass energy of 2.76 TeV, selected with a minimum bias trigger, jets are reconstructed in fine-grained, longitudinally segmented electromagnetic and hadronic calorimeters. The transverse energies of dijets in opposite hemispheres are observed to become systematically more unbalanced with increasing event centrality leading to a large number of events which contain highly asymmetric dijets. This is the first observation of an enhancement of events with such large dijet asymmetries, not observed in proton-proton collisions, which may point to an interpretation in terms of strong jet energy loss in a hot, dense medium. 相似文献
4.
Zhongbao Yin 《Central European Journal of Physics》2012,10(6):1361-1364
We present the results on elliptic flow with multi-strange baryons produced in Pb-Pb collisions at $\sqrt {s_{NN} } $ = 2.76 TeV. The analysis is performed with the ALICE detector at LHC. Multi-strange baryons are reconstructed via their decay topologies and the v 2 measurements are analyzed with the two-particle scalar product method. The p T differential v 2 values are compared to the viscous hydrodynamical (VISH2+1) model calculation and to the STAR measurements in Au-Au collisions at $\sqrt {s_{NN} } $ = 200 GeV. We found that the model describes ?? and ??v 2 measurements within uncertainties. The differential v 2 of ?? and ?? is similar to the STAR measurements at 200 GeV in Au-Au collisions. 相似文献
5.
Arsene I Bearden IG Beavis D Besliu C Budick B Bøggild H Chasman C Christensen CH Christiansen P Cibor J Debbe R Enger E Gaardhøje JJ Germinario M Hagel K Ito H Jipa A Jørdre JI Jundt F Jørgensen CE Karabowicz R Kim EJ Kozik T Larsen TM Lee JH Lee YK Lindal S Lystad R Løvhøiden G Majka Z Makeev A Mikelsen M Murray M Natowitz J Neumann B Nielsen BS Ouerdane D Płaneta R Rami F Ristea C Ristea O Röhrich D Samset BH Sandberg D Sanders SJ Sheetz RA Staszel P Tveter TS Videbaek F Wada R Yin Z 《Physical review letters》2005,94(3):032301
Charged-particle pseudorapidity densities are presented for the d + Au reaction at sqrt[s(NN)] = 200 GeV with -4.2 < or = eta < or = 4.2. The results, from the BRAHMS experiment at BNL Relativistic Heavy-Ion Collider, are shown for minimum-bias events and 0%-30%, 30%-60%, and 60%-80% centrality classes. Models incorporating both soft physics and hard, perturbative QCD-based scattering physics agree well with the experimental results. The data do not support predictions based on strong-coupling, semiclassical QCD. In the deuteron-fragmentation region the central 200 GeV data show behavior similar to full-overlap d+Au results at sqrt[s(NN)] = 19.4 GeV. 相似文献
6.
Back BB Baker MD Ballintijn M Barton DS Becker B Betts RR Bickley AA Bindel R Budzanowski A Busza W Carroll A Decowski MP García E Gburek T George N Gulbrandsen K Gushue S Halliwell C Hamblen J Harrington AS Henderson C Hofman DJ Hollis RS Hołyński R Holzman B Iordanova A Johnson E Kane JL Khan N Kulinich P Kuo CM Lee JW Lin WT Manly S Mignerey AC Noell A Nouicer R Olszewski A Pak R Park IC Pernegger H Reed C Remsberg LP Roland C Roland G Sagerer J Sarin P Sawicki P Sedykh I Skulski W Smith CE 《Physical review letters》2003,91(7):072302
We have measured transverse momentum distributions of charged hadrons produced in d+Au collisions at sqrt[s(NN)]=200 GeV. The spectra were obtained for transverse momenta 0.25
相似文献
7.
Adcox K Adler SS Ajitanand NN Akiba Y Alexander J Aphecetche L Arai Y Aronson SH Averbeck R Awes TC Barish KN Barnes PD Barrette J Bassalleck B Bathe S Baublis V Bazilevsky A Belikov S Bellaiche FG Belyaev ST Bennett MJ Berdnikov Y Botelho S Brooks ML Brown DS Bruner N Bucher D Buesching H Bumazhnov V Bunce G Burward-Hoy J Butsyk S Carey TA Chand P Chang J Chang WC Chavez LL Chernichenko S Chi CY Chiba J Chiu M Choudhury RK Christ T Chujo T Chung MS Chung P Cianciolo V Cole BA D'Enterria DG 《Physical review letters》2001,86(16):3500-3505
We present results for the charged-particle multiplicity distribution at midrapidity in Au-Au collisions at square root of [s(NN)] = 130 GeV measured with the PHENIX detector at RHIC. For the 5% most central collisions we find dN(ch)/d eta(vertical line eta = 0) = 622+/-1(stat)+/-41(syst). The results, analyzed as a function of centrality, show a steady rise of the particle density per participating nucleon with centrality. 相似文献
8.
9.
Adler C Ahammed Z Allgower C Amonett J Anderson BD Anderson M Averichev GS Balewski J Barannikova O Barnby LS Baudot J Bekele S Belaga VV Bellwied R Berger J Bichsel H Billmeier A Bland LC Blyth CO Bonner BE Boucham A Brandin A Bravar A Cadman RV Caines H Calderón de la Barca Sánchez M Cardenas A Carroll J Castillo J Castro M Cebra D Chaloupka P Chattopadhyay S Chen Y Chernenko SP Cherney M Chikanian A Choi B Christie W Coffin JP Cormier TM Cramer JG Crawford HJ Deng WS Derevschikov AA 《Physical review letters》2002,89(20):202301
Inclusive transverse momentum distributions of charged hadrons within 0.2
相似文献
10.
Abe F Albrow M Amidei D Anway-Wiese C Apollinari G Atac M Auchincloss P Azzi P Bacchetta N Baden AR Badgett W Bailey MW Bamberger A de Barbaro P Barbaro-Galtieri A Barnes VE Barnett BA Bauer G Baumann T Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Benjamin D Benlloch J Bensinger J Beretvas A Berge JP Bertolucci S Biery K Bhadra S Binkley M Bisello D Blair R Blocker C Bodek A Bolognesi V Booth AW Boswell C Brandenburg G Brown D Buckley-Geer E Budd HS Busetto G Byon-Wagner A 《Physical review letters》1993,70(26):4042-4046
11.
In this paper, we describe a study of charged particle yield as a function of pT for K*(892)0 and φ (1020) mesons in proton-proton (pp) and Pb-Pb collisions at $\sqrt{{s}_{NN}}$=2.76 TeV in the central rapidity region of ∣y∣<0.5, in a pT range of 0<pT <15 GeV c−1 in pp collisions and in a pT range of 0<pT<20 GeV c−1 in Pb-Pb collisions. We also investigated a very important ratio, the nuclear modification factor, to study the effects of the medium in the most central region, i.e. 0%-5% centrality. For data simulation, we used the EPOS-LHC and EPOS-1.99 models. To check the validity of these models’ simulations, we compared the data obtained from these Monte Carlo simulation programs with ALICE experimental data for $\sqrt{{s}_{NN}}$=2.76 TeV. It was concluded that the models’ predictions for the φ-meson in pp and for the most central Pb-Pb collisions disagreed with the ALICE data, and that the difference increased with pT. This may be connected with the essential role of collective parton behaviors which could not have been taken into account by the models. For K*0 mesons, both programs gave almost the same predictions, and with pT in the interval pT>3 GeV c−1, the predictions were very close to the experimental data. Both models gave higher predictions for the soft pT interval and lower predictions for the hard interactions. The values of the RAA distributions were lower than unity and both models were very close to the ALICE data. It is very interesting that the models were not able to describe the pT distributions, but they gave good predictions for their ratios. This may possibly be due to parton collective behaviors. We observed some additional suppression of K*0 at low values of pT with respect to φ-mesons, which may be related to the role of the masses of the particles in soft interactions. The rising trend for RAA in the region from pT =10 GeV c−1 to 20 GeV c−1 observed by the ALICE experiment was absent for the φ-mesons. 相似文献
12.
Abe F Albrow MG Amendolia SR Amidei D Antos J Anway-Wiese C Apollinari G Areti H Atac M Auchincloss P Azfar F Azzi P Bacchetta N Badgett W Bailey MW Bao J de Barbaro P Barbaro-Galtieri A Barnes VE Barnett BA Bartalini P Bauer G Baumann T Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Benjamin D Benlloch J Bensinger J Benton D Beretvas A Berge JP Bertolucci S Bhatti A Biery K Binkley M Bird F Bisello D Blair RE Blocker C Bodek A Bokhari W Bolognesi V Bortoletto D Boswell C Boulos T 《Physical review letters》1995,75(24):4358-4363
13.
Abe F Amidei D Apollinari G Ascoli G Atac M Auchincloss P Baden AR Barbaro-Galtieri A Barnes VE Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Bensinger J Beretvas A Berge P Bertolucci S Bhadra S Binkley M Blair R Blocker C Bofill J Booth AW Brandenburg G Brown D Byon A Byrum KL Campbell M Carey R Carithers W Carlsmith D Carroll JT Cashmore R Cervelli F Chadwick K Chapin T Chiarelli G Chinowsky W Cihangir S Cline D Connor D Contreras M Cooper J Cordelli M Curatolo M Day C DelFabbro R 《Physical review letters》1990,65(8):968-971
14.
Alexopoulos T Allen C Anderson EW Balamurali V Banerjee S Beery PD Bhat P Biswas NN Bujak A Carmony DD Carter T Cole P Choi Y DeBonte R DeCarlo V Erwin AE Findeisen C Goshaw AT Gutay LJ Hirsch AS Hojvat C Jennings JR Kenney VP Lindsey CS Loomis C LoSecco JM McMahon T McManus AP Morgan N Nelson K Oh SH Porile NT Rimai A Reeves D Robertson WJ Scharenberg RP Stringfellow BC Stampke SR Thompson M Turkot F Walker WD Wang CH Warchol J Wesson DK Zhan Y 《Physical review D: Particles and fields》1992,46(7):2773-2786
15.
16.
Chiu M Denisov A Garcia E Katzy J Makeev A Murray M White S 《Physical review letters》2002,89(1):012302
We report on the first measurement of mutual Coulomb dissociation in heavy-ion collisions. We employ forward calorimeters to measure neutron multiplicity at beam rapidity. The cross section for simultaneous electromagnetic breakup of Au nuclei at a nucleon-nucleon center of mass energy sqrt[s(NN)] = 130 GeV is sigma(MCD) = 3.67+/-0.26 barns, which is comparable to the geometrical cross section. The ratio of the electromagnetic to the total cross section is in good agreement with calculations, as is the neutron multiplicity distribution. 相似文献
17.
Alexopoulos T Allen C Anderson EW Areti H Banerjee S Beery PD Biswas NN Bujak A Carmony DD Carter T Cole P Choi Y De Bonte RJ Erwin AR Findeisen C Goshaw AT Gutay LJ Hirsch AS Hojvat C Kenney VP Lindsey CS LoSecco JM McMahon T McManus AP Morgan N Nelson KS Oh SH Piekarz J Porile NT Reeves D Scharenberg RP Stampke SR Stringfellow BC Thompson MA Turkot F Walker WD Wang CH Wesson DK 《Physical review letters》1990,64(9):991-994
18.
Adler SS Afanasiev S Aidala C Ajitanand NN Akiba Y Alexander J Amirikas R Aphecetche L Aronson SH Averbeck R Awes TC Azmoun R Babintsev V Baldisseri A Barish KN Barnes PD Bassalleck B Bathe S Batsouli S Baublis V Bazilevsky A Belikov S Berdnikov Y Bhagavatula S Boissevain JG Borel H Borenstein S Brooks ML Brown DS Bruner N Bucher D Buesching H Bumazhnov V Bunce G Burward-Hoy JM Butsyk S Camard X Chai JS Chand P Chang WC Chernichenko S Chi CY Chiba J Chiu M Choi IJ Choi J Choudhury RK Chujo T 《Physical review letters》2005,94(8):082301
The PHENIX experiment has measured midrapidity transverse momentum spectra (0.4
相似文献
19.
Abe F Amidei D Anway-Weiss C Apollinari G Atac M Auchincloss P Baden AR Bacchetta N Badgett W Bailey MW Bamberger A de Barbaro P Barbaro-Galtieri A Barnes VE Barnett BA Bauer G Baumann T Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Benjamin D Benlloch J Bensinger J Beretvas A Berge JP Bertolucci S Biery K Bhadra S Binkley M Bisello D Blair R Blocker C Bodek A Bolognesi V Booth AW Boswell C Brandenburg G Brown D Buckley-Geer E Budd HS Busetto G Byon-Wagner A Byrum KL Campagnari C 《Physical review letters》1992,69(20):2896-2900
20.
Alexopoulos T Allen C Anderson EW Balamurali V Banerjee S Beery PD Bhat P Bishop JM Biswas NN Bujak A Carmony DD Carter T Choi Y Cole P DeBonte R DeCarlo V Erwin AR Findeisen C Goshaw AT Gutay LJ Hirsch AS Hojvat C Jennings JR Kenney VP Lindsey CS Loomis C LoSecco JM McMahon T McManus AP Morgan N Nelson K Oh SH Porile NT Reeves D Rimai A Robertson WJ Scharenberg RP Stampke SR Stringfellow BC Thompson M Turkot F Walker WD Wang CH Warchol J Wesson DK Zhan Y 《Physical review letters》1993,71(10):1490-1493