Progress on 2017-LDRD-6: Geometry tagging for heavy ions at JLEIC Guohui Wei (for 2017-LDRD-6 group) JLEIC R&D Meeting, JLAB, Feb. 16, 2017 F. Lin

Outlines Introduction Progress Summary

Geometry tagging at JLEIC Goal Demonstrate that with the full-acceptance detector, JLEIC can realize key EIC physics goals Quark (color-charge) propagation and hadronization QCD Coherence and gluon saturation

Geometry tagging concept Intra-nuclear cascading increases with d (forward particle production) Also evaporation of nucleons from excited nucleus (very forward) Geometry tagging allows us to determine the path length d in the nucleus after the interaction by detecting the final state Nuclear fragments & particles in ion direction 197Au with tagging Without tagging, the average d in a nucleus scales as the radius (A1/3) Upper right plot shows 40 < A < 208 Tagging allows us to select (bins with) events for which the average d is very different from that for the entire nucleus Lower right plot (evaporation n-multiplicity tag)

Impact on key EIC measurements Quark propagation and hadronization (BeAGLE) h e' Knowing the path length will greatly improve our understanding of what happens when a quark propagates through nuclear matter. Energy loss, pT broadening, etc g* pT q e Coherence and gluon saturation (Sartre) At low x and Q2, the probe interacts coherently with all gluons in its path The gluon density can be increased by going to lower x (higher cm energy), or increasing the (nuclear) path length Heavy nuclei + selection of large path lengths through geometry tagging Extra boost from non-spherical nuclei?

White Paper Chapter 3: The Nucleus: A Laboratory for QCD (p59) Geometry tagging is essential for this goal! Low energy is, if anything, beneficial. ... with 40 GeV/A ion energies.

JLEIC is designed to catch all fragments Extended detector: 80+ m Ion FFQs 2nd focus on Roman pots dp/p proton-rich fragments neutron-rich fragments

JLEIC is designed to catch all fragments Ion e Detector momentum resolution 12 m downstream of the 2nd ion spectrometer dipole for a characteristic set of different initial angles. The right plot is an expanded version of the left figure. The red band is the nominal ±10  beam stay-clear region. Detector solenoid compensation, Chromaticity Compensation, Dynamic aperture study etc support a good background.

Team Theory Physics & generator CODE (BeAGLE & Sartre) A. Accardi Raphaël Dupre Tobias Toll (Shiv Nadar Uni., India) Liang Zheng (Wuhan Uni., China) Nuclear Physics (Supervision and Tagging detector) Nadel-Turonski, Pawel (PI) Mark Baker (MDBPADS) Charles E. Hyde (ODU), and his student (ODU) William Brooks, Kawtar Hafidi, Kijun Park Accelerator Physics (Accelerator and ion forward detection simulation ) Vasiliy Morozov (co-PI) Guohui Wei

Anticipated outcomes/results Year 1 (FY17) Implement new model codes (BeAGLE and Sartre) at JLab Interface to (GEMC) simulation of the full-acceptance detector Physics analysis of color propagation in eAu SIDIS in JLEIC kinematics First look at diffraction using Sartre (expanded to include Au, Pb, and Ca) Resolution for d and b in eAu for JLEIC using BeAGLE Year 2 (FY18) Implement 3D Glauber in BeAGLE for deformed nuclei (U) Use combination of BeAGLE and Sartre for detailed studies of incoherent and coherent diffraction (ground state through photon detection) Expand color propagation analysis to include U and Ca Investigate tagging impact of including negative forward hadrons (pions) Fully clarify the physics impact of key JLEIC detector and IR features Implement BeAGLE for JLab 12 GeV

Outlines Introduction Progress Unix Group setup in the computer system at Jlab Improvement on eA collision physics Implement codes (BeAGLE and Sartre) at Jlab and improvement Interface to (GEMC) simulation of the full-acceptance detector GEMC result and Physics analysis of color propagation in ePb collision (Preliminary)

Unix Group Setup LDRD group of 'ldgeom' has been created in /group.  This is also the 'O' drive on windows machines. increase the quota of the 'ldgeom' folder in /group from the default value of 2 GB to 100 GB in order to install software and store simulation data Email:     morozov@jlab.org Name:      Vasiliy Morozov Username:  morozov Staff:           letta Platform:  Windows,Netscape,20100101 Firefox Building:  ARC_7 Room:      704-5 Hostname:  129.57.112.125 Category:  GROUP REQUESTS Subject:   creating a new Unix group for LDRD project Submitted: 12/6/2016 10:32 AM

Improvement on eA collision physics Tobias Toll diffraction

Improvement on eA collision physics M. Baker, L. Zheng Two different d(fid) =6.8 fm trajectories A collision near the center with d(fid)=6.77 fm A collision near the edge with d(fid)=6.77 fm(>R!) with almost NO material

BeAGLE and Sartre at Jlab M. Baker, L. Zheng Implement the CODE of BeAGLE at Jlab

BeAGLE and Sartre at Jlab M. Baker, L. Zheng Improvement on output of BeAGLE

BeAGLE and Sartre at Jlab M. Baker, L. Zheng Feynman diagram and structure of BeAGLE Sartre installed at JLAB, Also installed GSL (Gnu Scientific Library) Installed sartre trunk version 205, Latest version 221 failed to compile at JLAB Sartre works not so well with ROOT 6 default @ JLAB root 6.0.8, BNL uses root 5.34/18 Sartre uses $ROOTSYS/include/Math/Interpolator.h, which exists in root 5 but NOT in root 6.

Interface to (GEMC) simulation Simulation process Currently, we use a LUND format for GEMC input, which is translated from GeAGLE output Maurizio Ungaro will make a new input format for GEMC input for BeAGLE

Preliminary results of color propagation in ePb GEMC simulation with BeAGLE output GEMC simulation with 10000 events of ePb collision GEMC simulation with 100 events of ePb collision e- pi- proton pi+ Ion neutron-black photons-blue

Preliminary results of color propagation in ePb GEMC result plot IP: 1188885 2nd Dipole exit: 71119 2212 Ion 12902 2112 n0 53968 321 K+ 1 211 Pi+ 7 130 K_L0 32 22 gama 4196 14 nu_mu 4 -14 nu_mu- 5 -2112 n0- 3rd FFQ exit: 72801 2212 Ion 14344 2112 n0 54097 321 K+ 6 211 Pi+ 20 130 K_L0 33 22 gama 4255 14 nu_mu 5 -14 nu_mu- -211 Pi- 28 -321 K- 3 -2112 n0- 4 2nd Focus point: 10511 2212 Ion 10509 321 K+ 1 -12 Nu_e

Preliminary results of color propagation in ePb Residual Ions in ePb collision: 10735 at all 10,000 events Pb: 208 Parton in a event Events’ number 1 9481 2 396 3 79 4 25 5 8 6 7 9 10 11 12 Total 10,000 IP: 1188885 ~ 5% of the 10,000 events have more than 2 of residual ions after collision.

Preliminary results of color propagation in ePb Ions

Preliminary results of color propagation in ePb

Preliminary results of color propagation in ePb Geometry tagging should allow us to significantly extend the reach of this “fm filter” in <d> as well as potentially providing narrower distributions in d (density weight distance). Neutron propagation and proton propagation are studied due to d and b The max multiplicity in color propagation are linear to d. The max multiplicity in events are located at certain value of b.

Preliminary results of color propagation in ePb Roughly, the max angle of neutron and proton in all events have the same Correlation to the d and b as Neutron propagation and proton propagation. linear to d. max value located at certain value of b. For clear study, more events are needed.

Summary The LDRD on geometry tagging for heavy ions at JLEIC is aimed at investigating pardon (color-charge) propagation in cold nuclear matter, as well as coherence phenomena and QCD at large gluon densities in nuclei. A Unix group named 'ldgeom' has been created at JLAB. The two generator CODE of BeAGLE and Sartre, have been Implemented in the 'ldgeom'. An example with 10,000 events at 10x40 Gev ePb are attained from the CODE of BeAGLE. Collision physics, CODEs, and interfaces are optimized for JLEIC cases. A preliminary study with ePb collision data is done in CODE GEMC. All final states are simulated in JLEIC ion forward detection area. And we find the max multiplicity in color propagation are linear to d, and located at certain value of b.

Thank you F. Lin