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arXiv · 1509.06727

Transverse energy production and charged-particle multiplicity at midrapidity in various systems from $\sqrt{s_{NN}}=7.7$ to 200 GeV

A. Adare·S. Afanasiev·C. Aidala·N. N. Ajitanand·Y. Akiba·R. Akimoto·H. Al-Bataineh·J. Alexander·M. Alfred·A. Al-Jamel·H. Al-Ta'ani·A. Angerami·K. Aoki·N. Apadula·L. Aphecetche·Y. Aramaki·R. Armendariz·S. H. Aronson·J. Asai·H. Asano·E. C. Aschenauer·E. T. Atomssa·R. Averbeck·T. C. Awes·B. Azmoun·V. Babintsev·M. Bai·X. Bai·G. Baksay·L. Baksay·A. Baldisseri·N. S. Bandara·B. Bannier·K. N. Barish·P. D. Barnes·B. Bassalleck·A. T. Basye·S. Bathe·S. Batsouli·V. Baublis·F. Bauer·C. Baumann·S. Baumgart·A. Bazilevsky·M. Beaumier·S. Beckman·S. Belikov·R. Belmont·R. Bennett·A. Berdnikov·Y. Berdnikov·J. H. Bhom·A. A. Bickley·M. T. Bjorndal·D. Black·D. S. Blau·J. G. Boissevain·J. S. Bok·H. Borel·K. Boyle·M. L. Brooks·D. S. Brown·J. Bryslawskyj·D. Bucher·H. Buesching·V. Bumazhnov·G. Bunce·J. M. Burward-Hoy·S. Butsyk·S. Campbell·A. Caringi·P. Castera·J. -S. Chai·B. S. Chang·J. -L. Charvet·C. -H. Chen·S. Chernichenko·C. Y. Chi·J. Chiba·M. Chiu·I. J. Choi·J. B. Choi·S. Choi·R. K. Choudhury·P. Christiansen·T. Chujo·P. Chung·A. Churyn·O. Chvala·V. Cianciolo·Z. Citron·C. R. Cleven·Y. Cobigo·B. A. Cole·M. P. Comets·Z. Conesa del Valle·M. Connors·P. Constantin·N. Cronin·N. Crossette
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Abstract

Measurements of midrapidity charged particle multiplicity distributions, $dN_{\rm ch}/dη$, and midrapidity transverse-energy distributions, $dE_T/dη$, are presented for a variety of collision systems and energies. Included are distributions for Au$+$Au collisions at $\sqrt{s_{_{NN}}}=200$, 130, 62.4, 39, 27, 19.6, 14.5, and 7.7 GeV, Cu$+$Cu collisions at $\sqrt{s_{_{NN}}}=200$ and 62.4 GeV, Cu$+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV, U$+$U collisions at $\sqrt{s_{_{NN}}}=193$ GeV, $d$$+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV, $^{3}$He$+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV, and $p$$+$$p$ collisions at $\sqrt{s_{_{NN}}}=200$ GeV. Centrality-dependent distributions at midrapidity are presented in terms of the number of nucleon participants, $N_{\rm part}$, and the number of constituent quark participants, $N_{q{\rm p}}$. For all $A$$+$$A$ collisions down to $\sqrt{s_{_{NN}}}=7.7$ GeV, it is observed that the midrapidity data are better described by scaling with $N_{q{\rm p}}$ than scaling with $N_{\rm part}$. Also presented are estimates of the Bjorken energy density, $\varepsilon_{\rm BJ}$, and the ratio of $dE_T/dη$ to $dN_{\rm ch}/dη$, the latter of which is seen to be constant as a function of centrality for all systems.

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A. Adare, S. Afanasiev, C. Aidala, N. N. Ajitanand, Y. Akiba, R. Akimoto, H. Al-Bataineh, J. Alexander, M. Alfred, A. Al-Jamel, H. Al-Ta'ani, A. Angerami, K. Aoki, N. Apadula, L. Aphecetche, Y. Aramaki, R. Armendariz, S. H. Aronson, J. Asai, H. Asano, E. C. Aschenauer, E. T. Atomssa, R. Averbeck, T. C. Awes, B. Azmoun, V. Babintsev, M. Bai, X. Bai, G. Baksay, L. Baksay, A. Baldisseri, N. S. Bandara, B. Bannier, K. N. Barish, P. D. Barnes, B. Bassalleck, A. T. Basye, S. Bathe, S. Batsouli, V. Baublis, F. Bauer, C. Baumann, S. Baumgart, A. Bazilevsky, M. Beaumier, S. Beckman, S. Belikov, R. Belmont, R. Bennett, A. Berdnikov, Y. Berdnikov, J. H. Bhom, A. A. Bickley, M. T. Bjorndal, D. Black, D. S. Blau, J. G. Boissevain, J. S. Bok, H. Borel, K. Boyle, M. L. Brooks, D. S. Brown, J. Bryslawskyj, D. Bucher, H. Buesching, V. Bumazhnov, G. Bunce, J. M. Burward-Hoy, S. Butsyk, S. Campbell, A. Caringi, P. Castera, J. -S. Chai, B. S. Chang, J. -L. Charvet, C. -H. Chen, S. Chernichenko, C. Y. Chi, J. Chiba, M. Chiu, I. J. Choi, J. B. Choi, S. Choi, R. K. Choudhury, P. Christiansen, T. Chujo, P. Chung, A. Churyn, O. Chvala, V. Cianciolo, Z. Citron, C. R. Cleven, Y. Cobigo, B. A. Cole, M. P. Comets, Z. Conesa del Valle, M. Connors, P. Constantin, N. Cronin, N. Crossette. 2016-02-23. Transverse energy production and charged-particle multiplicity at midrapidity in various systems from $\sqrt{s_{NN}}=7.7$ to 200 GeV. https://doi.org/10.1103/physrevc.93.024901

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