Thu·Aug 4, 2016Thursday·August 4, 2016

1. 01*

   Chiral Magnetic Effect Task Force Report

   Vladimir Skokov🇺🇸 · Paul Sorensen🇺🇸 · Volker Koch🇺🇸 · Soeren Schlichting🇺🇸 · Jim Thomas🇺🇸 · Sergei Voloshin🇺🇸 · Gang Wang🇺🇸 · Ho-Ung Yee🇺🇸

   In this report, we briefly examine the current status of the study of the chiral magnetic effect including theory and experimental progress. We recommend future strategies for resolving uncertainties in interpretation including recommendations for theoretical work, recommendations for measurements based on data collected in the past five years, and recommendations for beam use in the coming years of RHIC. We have specifically investigated the case for colliding nuclear isobars (nuclei with the same mass but different charge) and find the case compelling. We recommend that a program of nuclear isobar collisions to isolate the chiral magnetic effect from background sources be placed as a high priority item in the strategy for completing the RHIC mission.

   ↳ nucl-thhep-phnucl-exCPC(2017)·161 citations
2. 02*

   Rosenbluth separation of the ${\pi }^0$ electroproduction cross section

   M. Defurne · M. Mazouz · H. Albataineh · K. Allada · K. A. Aniol · V. Bellini · M. Benali · W. Boeglin · P. Bertin · M. Brossard · A. Camsonne · M. Canan and 82 other authors

   We present deeply virtual ${\pi }^0$ electroproduction cross-section measurements at $x_B$=0.36 and three different $Q^2$--values ranging from 1.5 to 2 GeV${}^2$, obtained from experiment E07-007 that ran in the Hall A at Jefferson Lab. The Rosenbluth technique was used to separate the longitudinal and transverse responses. Results demonstrate that the cross section is dominated by its transverse component, and thus is far from the asymptotic limit predicted by perturbative Quantum Chromodynamics. An indication of a non-zero longitudinal contribution is provided by the interference term ${\sigma }_{LT}$ also measured. Results are compared with several models based on the leading twist approach of Generalized Parton Distributions (GPDs). In particular, a fair agreement is obtained with models where the scattering amplitude is described by a convolution of chiral-odd (transversity) GPDs of the nucleon with the twist-3 pion distribution amplitude. Therefore, neutral pion electroproduction may offer the exciting possibility of accessing transversity GPDs through experiment.

   ↳ hep-exnucl-exPRL(2016)·75 citations
3. 03*

   Probing the resonance of Dirac particle by the application of complex momentum representation

   Niu Li🇨🇳 · Min Shi🇨🇳 · Jian-You Guo🇨🇳 · Zhong-Ming Niu🇨🇳 · Haozhao Liang🇯🇵

   Resonance plays critical roles in the formation of many physical phenomena, and several methods have been developed for the exploration of resonance. In this work, we propose a new scheme for resonance by solving the Dirac equation in complex momentum representation, in which the resonant states are exposed clearly in complex momentum plane and the resonance parameters can be determined precisely without imposing unphysical parameters. Combining with the relativistic mean-field theory, this method is applied to probe the resonances in ${}^{120}$Sn with the energies, widths, and wavefunctions being obtained. Comparing with other methods, this method is not only very effective for narrow resonances, but also can be reliably applied to broad resonances.

   ↳ nucl-thhep-thnucl-exquant-phPRL(2016)·60 citations
4. 04*

   High Precision Momentum Calibration of the Magnetic Spectrometers at MAMI for Hypernuclear Binding Energy Determination

   A. Margaryan🇦🇲 · J.R.M. Annand🇬🇧 · P. Achenbach🇩🇪 · R. Ajvazyan🇦🇲 · H. Elbakyan · R. Montgomery🇬🇧 · S. N. Nakamura🇯🇵 · J. Pochodzalla🇩🇪 · F. Schulz🇩🇪 · Y. Toyama · S. Zhamkochyan🇦🇲

   We propose a new method for absolute momentum calibration of magnetic spectrometers used in nuclear physics, using the time-of-flight (TOF), differences of pairs of particles with different masses. In cases where the flight path is not known, a calibration can be determined by using the TOF differences of two pair combinations of three particles. A Cherenkov detector, read out by a radio frequency photomultiplier tube, is considered as the high-resolution and highly stable TOF detector. By means of Monte Carlo simulations it is demonstrated that the magnetic spectrometers at the MAMI electron-scattering facility can be calibrated absolutely with an accuracy $\delta p/p\le 10^{-4}$, which will be crucial for high precision determination of hypernuclear masses.

   ↳ physics.ins-detnucl-exNucl.Instrum.Meth.A(2017)·4 citations
5. 05*

   FastDIRC: a fast Monte Carlo and reconstruction algorithm for DIRC detectors

   John Hardin🇺🇸 · Mike Williams🇺🇸

   FastDIRC is a novel fast Monte Carlo and reconstruction algorithm for DIRC detectors. A DIRC employs rectangular fused-silica bars both as Cherenkov radiators and as light guides. Cherenkov-photon imaging and time-of-propagation information are utilized by a DIRC to identify charged particles. GEANT-based DIRC Monte Carlo simulations are extremely CPU intensive. The FastDIRC algorithm permits fully simulating a DIRC detector more than 10000 times faster than using GEANT. This facilitates designing a DIRC-reconstruction algorithm that improves the Cherenkov-angle resolution of a DIRC detector by about 30% compared to existing algorithms. FastDIRC also greatly reduces the time required to study competing DIRC-detector designs.

   ↳ physics.data-anhep-exnucl-exphysics.ins-detJINST(2016)·16 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.