The Spin Physics Detector collaboration proposes to install a universal detector in the second interaction point of the NICA collider under construction (JINR, Dubna) to study the spin structure of the proton and deuteron and other spin-related phenomena using a unique possibility to operate with polarized proton and deuteron beams at a collision energy up to 27 GeV and a luminosity up to 10^32 cm^-2 s^-1. As the main goal, the experiment aims to provide access to the gluon TMD PDFs in the proton and deuteron, as well as the gluon transversity distribution and tensor PDFs in the deuteron, via the measurement of specific single and double spin asymmetries using different complementary probes such as charmonia, open charm, and prompt photon production processes. Other polarized and unpolarized physics is possible, especially at the first stage of NICA operation with reduced luminosity and collision energy of the proton and ion beams. This document is dedicated exclusively to technical issues of the SPD setup construction.

M.M. Aggarwal, Z. Ahammed, A.L.S. Angelis, V. Antonenko, V. Arefiev, V. Astakhov, V. Avdeitchikov, T.C. Awes, P.V.K.S. Baba, S.K. Badyal, S. Bathe, B. Batiounia, C. Baumann, T. Bernier, K.B. Bhalla, V.S. Bhatia, C. Blume, D. Bucher, H. Büsching, L. Carlén, S. Chattopadhyay, M.P. Decowski, H. Delagrange, P. Donni, M.R. Dutta Majumdar, K. El Chenawi, A.K. Dubey, K. Enosawa, S. Fokin, V. Frolov, M.S. Ganti, S. Garpman, O. Gavrishchuk, F.J.M. Geurts, T.K. Ghosh, R. Glasow, B. Guskov, H. Å.Gustafsson, H. H.Gutbrod, I. Hrivnacova, M. Ippolitov, H. Kalechofsky, R. Kamermans, K. Karadjev, K. Karpio, B. W. Kolb, I. Kosarev, I. Koutcheryaev, A. Kugler, P. Kulinich, M. Kurata, A. Lebedev, H. Löhner, L. Luquin, D.P. Mahapatra, V. Manko, M. Martin, G. Mart́ınez, A. Maximov, Y. Miake, G.C. Mishra, B. Mohanty, M.-J. Mora, D. Morrison, T. Mukhanova, D. S. Mukhopadhyay, H. Naef, B. K. Nandi, S. K. Nayak, T. K. Nayak, A. Nianine, V. Nikitine, S. Nikolaev, P. Nilsson, S. Nishimura, P. Nomokonov, J. Nystrand, A. Oskarsson, I. Otterlund, S. Pavliouk, T. Peitzmann, D. Peressounko, V. Petracek, S.C. Phatak, W. Pinganaud, F. Plasil, M.L. Purschke, J. Rak, M. Rammler, R. Raniwala, S. Raniwala, N.K. Rao, F. Retiere, K. Reygers, G. Roland, L. Rosselet, I. Roufanov, C. Roy, J.M. Rubio, S.S. Sambyal, R. Santo, S. Sato, H. Schlagheck, H.-R. Schmidt, Y. Schutz, G. Shabratova, T.H. Shah, I. Sibiriak, T. Siemiarczuk, D. Silvermyr, B.C. Sinha, N. Slavine, K. Söderström, G. Sood, S.P. Sørensen, P. Stankus, G. Stefanek, P. Steinberg, E. Stenlund, M. Sumbera, T. Svensson, A. Tsvetkov, L. Tykarski, E.C.v.d. Pijll, N.v. Eijndhoven, G.J.v. Nieuwenhuizen, A. Vinogradov, Y.P. Viyogi, A. Vodopianov, S. Vörös, B. Wys louch, G.R. Young 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22 (WA98 Collaboration) 21 University of Panjab, Chandigarh 160014, India 32 Variable Energy Cyclotron Centre, Calcutta 700064, India 43 University of Geneva, CH-1211 Geneva 4,Switzerland 54 RRC “Kurchatov Institute”, RU-123182 Moscow 65 Joint Institute for Nuclear Research, RU-141980 Dubna, Russia 76 Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6372, USA 87 University of Jammu, Jammu 180001, India 98 University of Münster, D-48149 Münster, Germany 109 SUBATECH, Ecole des Mines, Nantes, France 1110 University of Rajasthan, Jaipur 302004, Rajasthan, India 1211 University of Lund, SE-221 00 Lund, Sweden 1312 MIT Cambridge, MA 02139 1413 Institute of Physics, Bhubaneswar 751005, India 1514 University of Tsukuba, Ibaraki 305, Japan 1615 Universiteit Utrecht/NIKHEF, NL-3508 TA Utrecht, The Netherlands 1716 KVI, University of Groningen, NL-9747 AA Groningen, The Netherlands 1817 Gesellschaft für Schwerionenforschung (GSI), D-64220 Darmstadt, Germany 1918 Nuclear Physics Institute, CZ-250 68 Rez, Czech Rep. 2019 Institute for Nuclear Studies, 00-681 Warsaw, Poland 2120 University of Tennessee, Knoxville, Tennessee 37966, USA Deceased (Dated: May 17, 2021)

. The results of the SERP-E-184 experiment at the U-70 accelerator (IHEP, Protvino) are presented. Interactions of the 70GeV proton beam with carbon, silicon and lead targets were studied to detect decays of charmed D^0 , D̅^0 , D^+ , D^- mesons and Λ_c^+ baryon near their production threshold. Measurements of lifetimes and masses have shown a good agreement with PDG data. The inclusive cross-sections of charm production and their A -dependences have been obtained. The yields of these particles are compared with the theoretical predictions and the data of other experiments. The measured cross-section of the total open charm production ( σ_ tot(cc̅) = 7.1 ± 2.3( stat) ± 1.4( syst) μb/nucleon) at the collision c.m. energy √ s = 11.8 GeV is well above the QCD model predictions. The contributions of different kinds of charmed particles to the total cross-section of the open charm production in proton-nucleus interactions vary with energy.

The results of the SERP-E-184 experiment at the U-70 accelerator (IHEP, Protvino) are presented. Interactions of the 70GeV proton beam with carbon, silicon and lead targets were studied to detect decays of charmed \(D^{0}\), \(\bar{D}^{0}\), \(D^{+}\), \(D^{-}\) mesons and \(\Lambda_{c}^{+}\) baryon near their production threshold. Measurements of lifetimes and masses have shown a good agreement with PDG data. The inclusive cross-sections of charm production and their A-dependences have been obtained. The yields of these particles are compared with the theoretical predictions and the data of other experiments. The measured cross-section of the total open charm production ( \(\sigma_{\rm tot}(c\bar{c}) = 7.1 \pm 2.3({\rm stat}) \pm 1.4({\rm syst})\) μb/nucleon) at the collision c.m. energy \(\surd s = 11.8\) GeV is well above the QCD model predictions. The contributions of different kinds of charmed particles to the total cross-section of the open charm production in proton-nucleus interactions vary with energy.

he results of the SERP-E-184 experiment at the U-70 accelerator (IHEP, Protvino) are presented. Interactions of the 70 GeV proton beam with C, Si and Pb targets were studied to detect decays of charmed $D^0$, $\overline D^0$, $D^+$, $D^-$ mesons and $\Lambda _c^+$ baryon near their production threshold. Measurements of lifetimes and masses are shown a good agreement with PDG data. The inclusive cross sections of charm production and their A-dependencies were obtained. The yields of these particles are compared with the theoretical predictions and the data of other experiments. The measured cross section of the total open charm production ($\sigma _{\mathrm {tot}}(c\overline c)$ = 7.1 $\pm $ 2.3(stat) $\pm $1.4(syst) $\mu $b/nucleon) at the collision c.m. energy $\sqrt {s}$ = 11.8 GeV is well above the QCD model predictions. The contributions of different species of charmed particles to the total cross section of the open charm production in proton-nucleus interactions vary with energy.

Experimental and theoretical studies of direct photon production in hadronic collisions essentially expand our insights in multiparticle production mechanisms. These photons are useful probes to investigate nuclear matter at all stages of the interaction. Soft photons play a particular role in these studies. Until now we have no explanation for the experimentally observed excess of soft photons. These photons have low transverse momenta \( p_{T} < 0.1\) GeV/c, \( \vert x\vert < 0.01\) . In this domain their yield exceeds the theoretical estimates by 5-8 times. The registration of soft photons at Nuclotron (LHEP, JINR) has been carried out by the electromagnetic calorimeter built by the SVD-2 Collaboration. Soft photon electromagnetic calorimeter was tested at U-70, IHEP (Protvino). For the first time the soft photon yield at interactions of 3.5A GeV/c per nucleon deuterium and lithium beams has been measured. The obtained energy spectra confirm the increased yield of soft photons with their energy less than 50MeV (in the laboratory system) in comparison with theoretical predictions and agree with previous experiments at high-energy interactions. It is planned to continue soft photon study at the future accelerator complex NICA with heavy-ion beams.

First results of a soft photon yield in nucleus-nuclear interactions at 3.5 GeV per nucleon are presented. These photons have been registered at Nuclotron (LHEP, JINR) by an electromagnetic calorimeter built in the SVD Collaboration. The obtained spectra confirm the excess yield in the energy region less than 50 MeV in comparison with theoretical predictions and agree with previous experiments at high-energy interactions.

M.M. Aggarwal, Z. Ahammed, A.L.S. Angelis, V. Antonenko, V. Arefiev, V. Astakhov, V. Avdeitchikov, T.C. Awes, P.V.K.S. Baba, S.K. Badyal, S. Bathe, B. Batiounia, T. Bernier, K.B. Bhalla, V.S. Bhatia, C. Blume, D. Bucher, H. Büsching, L. Carlén, S. Chattopadhyay, M.P. Decowski, H. Delagrange, P. Donni, M.R. Dutta Majumdar, K. El Chenawi, A.K. Dubey, K. Enosawa, S. Fokin, V. Frolov, M.S. Ganti, S. Garpman, O. Gavrishchuk, F.J.M. Geurts, T.K. Ghosh, R. Glasow, B. Guskov, H. Å.Gustafsson, H. H.Gutbrod, I. Hrivnacova, M. Ippolitov, H. Kalechofsky, K. Karadjev, K. Karpio, B. W. Kolb, I. Kosarev, I. Koutcheryaev, A. Kugler, P. Kulinich, M. Kurata, A. Lebedev, H. Löhner, L. Luquin, D.P. Mahapatra, V. Manko, M. Martin, G. Mart́ınez, A. Maximov, Y. Miake, G.C. Mishra, B. Mohanty, M.-J. Mora, D. Morrison, T. Mukhanova, D. S. Mukhopadhyay, H. Naef, B. K. Nandi, S. K. Nayak, T. K. Nayak, A. Nianine, V. Nikitine, S. Nikolaev, P. Nilsson, S. Nishimura, P. Nomokonov, J. Nystrand, A. Oskarsson, I. Otterlund, T. Peitzmann, D. Peressounko, V. Petracek, W. Pinganaud, F. Plasil, M.L. Purschke, J. Rak, R. Raniwala, S. Raniwala, N.K. Rao, F. Retiere, K. Reygers, G. Roland, L. Rosselet, I. Roufanov, C. Roy, J.M. Rubio, S.S. Sambyal, R. Santo, S. Sato, H. Schlagheck, H.-R. Schmidt, Y. Schutz, G. Shabratova, T.H. Shah, I. Sibiriak, T. Siemiarczuk, D. Silvermyr, B.C. Sinha, N. Slavine, K. Söderström, G. Sood, S.P. Sørensen, P. Stankus, G. Stefanek, P. Steinberg, E. Stenlund, M. Sumbera, T. Svensson, A. Tsvetkov, L. Tykarski, E.C.v.d. Pijll, N.v. Eijndhoven, G.J.v. Nieuwenhuizen, A. Vinogradov, Y.P. Viyogi, A. Vodopianov, S. Vörös, B. Wys louch, G.R. Young (WA98 Collaboration) 1 University of Panjab, Chandigarh 160014, India 2 Variable Energy Cyclotron Centre, Calcutta 700064, India 3 University of Geneva, CH-1211 Geneva 4,Switzerland 4 RRC “Kurchatov Institute”, RU-123182 Moscow 5 Joint Institute for Nuclear Research, RU-141980 Dubna, Russia 6 Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6372, USA 7 University of Jammu, Jammu 180001, India 8 University of Münster, D-48149 Münster, Germany 9 SUBATECH, Ecole des Mines, Nantes, France 10 University of Rajasthan, Jaipur 302004, Rajasthan, India 11 University of Lund, SE-221 00 Lund, Sweden 12 MIT Cambridge, MA 02139 13 Institute of Physics, Bhubaneswar 751005, India 14 University of Tsukuba, Ibaraki 305, Japan 15 Universiteit Utrecht/NIKHEF, NL-3508 TA Utrecht, The Netherlands 16 KVI, University of Groningen, NL-9747 AA Groningen, The Netherlands 17 Gesellschaft für Schwerionenforschung (GSI), D-64220 Darmstadt, Germany 18 Nuclear Physics Institute, CZ-250 68 Rez, Czech Rep. 19 Institute for Nuclear Studies, 00-681 Warsaw, Poland and 20 University of Tennessee, Knoxville, Tennessee 37966, USA (Dated: February 14, 2014)

The new-generation high-granularity Shashlyk EM calorimeter readout by micropixel avalanche photodiodes (MAPD) with precision thermostabilization based on the Peltier element is designed, constructed end tested. MAPD-3N with superhigh pixel density 1.5×104 mm−2 and area 3×3 mm2 manufactured by the Zecotek Company were used in the photodetector unit.

Measurements of direct photon production in p+Pb and p+C collisions at $\sqrt{s_\mathrm{NN}} = 17.4\mathrm{GeV}$ are presented. Upper limits on the direct photon yield as a function of $p_\mathrm{T}$ are derived and compared to the results for Pb+Pb collisions at $\sqrt{s_\mathrm{NN}} = 17.3$ GeV. The production of the $\eta$ meson, which is an important input to the direct photon signal extraction, has been determined in the $\eta \rightarrow 2\gamma$ channel for p+C collisions at $\sqrt{s_\mathrm{NN}} = 17.4\mathrm{GeV}$.

A double polarized measurement of quasi-elastic electron scattering in the 2H(−→e , e′−→n ) reaction is proposed at values of negative four-momentum transfer Q = 1.5, 2.0, 2.5, 3.0, 4.0, 6.0 (GeV/c). The ratio of electric to magnetic elastic form factors GE/G n M will be extracted from the ratio of transverse and longitudinal components of the spin polarization Px/Pz, which is transferred to the recoiling neutron from an incident, longitudinally polarized electron. The experiment will be performed in Hall-A of Je erson Laboratory, as part of the program to measure the four nucleon Sachs form factors, and will utilize many of the common components of the Super BigBite apparatus. Scattered electrons will be detected in the BigBite large acceptance spectrometer and recoiling neutrons in a polarimeter consisting of plastic scintillator analyzers and the HCAL hadron calorimeter. The 48D48 dipole will perform neutron spin precession and sweeping of charged background out of the neutron arm acceptance. The array of plastic scintillator bars, in which neutrons will scatter in order to analyze the incident spin orientation, will be a new addition to the Super BigBite apparatus.. This experiment will complement experiments E02-013 and E12-09-016, where the struck neutron is polarized in the initial state in a −−→ He target. It employs an independent experimental technique to extract a fundamental observable which is highly challenging to measure. In addition the necessary corrections for bound-neutron e ects and nal state interactions in H and He will be rather di erent and in principle more straight forward for A=2 system. We estimate, for the employed parametrization of form-factor (BLAST), that the ratio GE/G n M will be measured to a relative (statistical) precision of 2.5 to 5%, up to 4 (GeV/c) and 10% at 6 (GeV/c). The systematic uncertainty will be ∼ 3%. A total beam time of 1054 hr to measure the ratio and perform all necessary commissioning and calibration of apparatus is requested.

In many detectors based on scintillators the photomultiplier tubes (PMTs) are used as photodetectors. At present photodiodes are finding wide application. Solid state photodetectors allow operation in strong magnetic fields that are often present in applications, e.g. some calorimeters operating near magnets, combined PET and MRT, etc. The photon detection efficiency (PDE) of photodiodes may reach values a few times higher than that of PMTs. Also, they are rigid, compact and have relatively low operating voltage. In the last few years Micropixel Avalanche PhotoDiodes (MAPD) have been developed and started to be used. The MAPD combines a lot of advantages of semiconductor photodetectors and has a high gain, which is close to that of the PMT. Yet, they have some disadvantages, and one of them is a limited dynamic range that corresponds to a total number of pixels. The novel deep microwell MAPD with high pixel density produced by the Zecotek Company partially avoids this disadvantage. In this paper characteristics of these photodetectors are presented in comparison with the PMT characteristics. The results refer to measurements of the gain, PDE, cross-talks, photon counting and applications: beam test results of two different “Shashlyk” EM calorimeters for COMPASS (CERN) and NICA-MPD (JINR) with the MAPD readout and a possibility of using the MAPD in PET.

The main properties of two different Shashlyk EM calorimeter modules readout by novel micropixel avalanche photodiodes (MAPD) with microwell structure and very high density of pixels were studied at the T9 CERN PS test-beam facility. A MAPD-3A with density of pixels 1.5×104 mm−2 and area 3×3 mm2 manufactured by Zecotek Company was used in our test.

M.M. Aggarwal, Z. Ahammed, A.L.S. Angelis, V. Antonenko, V. Arefiev , V. Astakhov , V. Avdeitchikov , T.C. Awes, P.V.K.S. Baba, S.K. Badyal, S. Bathe, B. Batiounia , T. Bernier, K.B. Bhalla, V.S. Bhatia, C. Blume, D. Bucher, H. Büsching, L. Carlen, S. Chattopadhyay, A.C. Das, M.P. Decowski, P. Donni, A.K. Dubey, M.R. Dutta Majumdar, K. Enosawa, S. Fokin, V. Frolov , M.S. Ganti, S. Garpman, O. Gavrishchuk , F.J.M. Geurts, R. Glasow, B. Guskov , H.A. Gustafsson, H.H. Gutbrod , I. Hrivnacova, M. Ippolitov, H. Kalechofsky, R. Kamermans, K. Karadjev, K. Karpio, B.W. Kolb, I. Kosarev , I. Koutcheryaev, A. Kugler, P. Kulinich, M. Kurata, A. Lebedev, H. Löhner , D.P. Mahapatra, V. Manko, M. Martin, Y. Miake, G.C. Mishra, B. Mohanty, D. Morrison, D.S. Mukhopadhyay, H. Naef, B.K. Nandi, S.K. Nayak, T.K. Nayak, A. Nianine, V. Nikitine , S. Nikolaev, S. Nishimura, P. Nomokov , J. Nystrand, A. Oskarsson, I. Otterlund, S.C. Phatak, S. Pavliouk , T. Peitzmann, V. Petracek, F. Plasil, M.L. Purschke, J. Rak, R. Raniwala, S. Raniwala, N.K. Rao, F. Retiere , K. Reygers, G. Roland, L. Rosselet, I. Roufanov , J.M. Rubio, S.S. Sambyal, R. Santo, S. Sato, H. Schlagheck, H.-R. Schmidt, Y. Schutz , G. Shabratova , I. Sibiriak, T. Siemiarczuk, B.C. Sinha, N. Slavine , K. Söderström, G. Sood, S.P. Sørensen, P. Stankus, G. Stefanek, P. Steinberg, E. Stenlund, M. Sumbera, T. Svensson, M.D. Trivedi, A. Tsvetkov, L. Tykarski, J. Urbahn, N.v. Eijndhoven, G.J.v. Nieuwenhuizen, A. Vinogradov, Y.P. Viyogi, A. Vodopianov , S. Vörös, B. Wyslouch, and G.R. Young

Several hadronic observables have been studied in central 158A GeV Pb+Pb collisions using data measured by the WA98 experiment at CERN: single π and K production, as well as twoand three-pion interferometry. The Wiedemann-Heinz hydrodynamical model has been fitted to the pion spectrum, giving an estimate of the temperature and transverse flow velocity. Bose-Einstein correlations between two identified π have been analysed as a function of kT , using two different parameterizations. The results indicate that the source does not have a strictly boost invariant expansion or spend time in a long-lived intermediate phase. A comparison between data and a hydrodynamical based simulation shows very good agreement for the radii parameters as a function of kT . The pion phase-space density at freeze-out has been measured and agrees well with the Tomás̆ik-Heinz model. A large pion chemical potential close to the condensation limit of mπ seems to be excluded. The threepion Bose-Einstein interferometry shows a substantial contribution of the genuine three-pion correlation, but not quite as large as expected for a fully chaotic and symmetric source.

Neutral pion transverse momentum spectra were measured in p+C and p+Pb collisions at sqrt[S{NN}]=17.4 GeV at midrapidity (2.3 less than or approximately equal eta{lab} less than or approximately equal 3.0) over the range 0.7 less than or approximately equal p{T} less than or approximately equal 3.5 GeV/c. The spectra are compared to pi{0} spectra measured in Pb+Pb collisions at sqrt[S{NN}]=17.3 GeV in the same experiment. For a wide range of Pb+Pb centralities (N{part} less than or approximately equal 300), the yield of pi{0}'s with p{T} greater than or approximately equal 2 GeV/c is larger than or consistent with the p+C or p+Pb yields scaled with the number of nucleon-nucleon collisions (N{coll}), while for central Pb+Pb collisions with N{part}greater than or approximately equal 350, the pi{0} yield is suppressed.

The effect of the final state Coulomb interaction on particles produced in Pb+Pb collisions at 158 A GeV/c has been investigated in the WA98 experiment through the study of the pi-/pi+ and K-/K+ ratios measured as a function of transverse mass. While the ratio for kaons shows no significant transverse mass dependence, the pi-/pi+ ratio is enhanced at small transverse mass values with an enhancement that increases with centrality. A silicon pad detector located near the target is used to estimate the contribution of hyperon decays to the pi-/pi+ ratio. The comparison of results with predictions of the RQMD model in which the Coulomb interaction has been incorporated allows to place constraints on the time of the pion freeze-out.