Dr. Elena Long
 
   
  A liquid helium level sensor is placed inside the superconducting magnet's cryostat to ensure that the solenoid stays at 4 K.  
 

Fig. 1 - Dr. Long installing the solenoid for UNH's new DNP polarizer.

 

 

Fig. 2 - Projected uncertainties for the b1 experiment.

 

 

Fig. 3 - Projected uncertainties for the Azz experiment.

Dr. Elena Long is a Post Doctoral Research Associate at the University of New Hampshire whose research focuses on the internal structure of nucleons. Links above go to the wiki for the b1 experiment, the wiki for the EG4 experiment, the quasi-elastic experiment progress website, the website for the Quasi-Elastic Family of Experiment, the LGBT+ Physicists website, a copy of her CV, and her Ph.D. dissertation.

A recent recepient of the JSA Promising Young Scientist Award and the JSA Post Doctoral Research Prize, Elena is researching the ways that a tensor-polarized target can be utilized to understand nuclear effects. Currently, she is working on measuring the deuteron structure function, b1, which was approved as the Jefferson Lab experiment E12-13-011. The b1 structure function only exists in tensor polarized, spin-1 particles. If the deuteron is a simple combination of a proton and neutron, b1 is zero. All conventional models predict b1 to be vanishingly small at 0.1 < x < 0.7. However, a previous measurement by HERMES showed a large measurement around x = 0.45 that's 2 sigma from zero. The current measurement looks to greatly improve the uncertainty in this range, as well as map out a possible sign change in b1.

Elena is also the lead spokesperson on an approved experiment to do the first measurement on the quasi-elastic tensor asymmetry Azz. By utilizing tensor polarization, which enhances the deuteron's D-state, and looking at kinematics in the x>1 region, short range nuclear effects are enhanced. This experiment will provide insight into relativistic nucleon-nucleon calculations, such as light cone and virtual neucleon methods, as well as provide new experimental constraints on decades-old quetsions about the S/D ratio of deuteron wavefunctions.

(Click here for a description of Azz written for a 6-year old)

Her dissertation measured asymmetries that tested models used to extract the neutron form factors. Many extractions are done with plane wave impulse approximaion (PWIA), which predicts an asymmetry (Ay0) of vertically polarized 3He(e,e'n) to be exactly zero. Non-zero asymmetry is indicative of final state interactions, meson exchange currents, and other effects beyond PWIA. She also obtained 3He(e,e'n) asymmetries with the target polarized longitudinal to a polarized electron beam from which the magnetic form factor of the neutron (GMn) can be extracted and with the target polarized transverse to a polarized electron beam and parallel to the q-vector from which the electric form factor of the neutron (GEn) can be extracted.

The video below is from a Google Hangout Seminar that was hosted by the University of Central Arkansas, in which Dr. Long gives an overview of her field and ends with her recent work on electron scattering from tensor polarized deuterons.


Along with her research, Elena has been working on creating resources for people in physics. In 2014, she was elected to the Jefferson Lab User's Group Board of Directors to represent the needs of Post-Docs associated with the lab. In 2009, she founded an organization, LGBT+ Physicists, that has grown to include networking opportunites, an OutList, and is continuing to make physics better for the LGBT+ people in the field. She is also the Vice President of Diversity and Inclusion for oSTEM, Inc. where she has been working towards making the STEM fields more accessible to LGBT+ undergraduate and graduate students.

Approved Experiment Proposals

E12-15-005: Measurements of the Quasi-Elastic and Elastic Deuteron Tensor Asymmetries (Lead Spokesperson)

E12-13-011: The Deuteron Tensor Structure Function b1 (Spokesperson)

E12-11-008: A Proposal for the DarkLight Experiment at the Jefferson Laboratory Free Electron Laser

Letter of Intent

LOI12-14-002: Tensor Asymmetry Azz in the x>1 Region (Contact Spokesperson)

Publication List

Y. X. Zhao, et al., Double spin asymmetries of inclusive hadron electroproduction from a transversely polarized 3He target, Phys. Rev. C 92 015207 (2015)

D. Parno, et al., Precision measurement of A1n in the deep inelastic regime, Phys. Lett. B 744 309 (2015)

M. Mihovilovič, G. Jin, E. Long, Y-W. Zhang, et al., Measurement of Double-Polarization Asymmetries in the Quasielastic 3H⃗e(e⃗,e'd) Process, Phys. Rev. Lett. 113 232505 (2014)

Y. Zhang, et al., Measurement of "pretzelosity" asymmetry of charged pion production in semi-inclusive deep inelastic scattering on a polarized 3He target, Phys. Rev. C 90 055209 (2014)

E. Long, Potential for a Tensor Asymmetry Azz in the x>1 Region at Jefferson Lab, J. Phys.: Conf. Ser. 543 012010 (2014)

Y. X. Zhao, et al., Single spin asymmetries in charged kaon production from semi-inclusive deep inelastic scattering on a transversely polarized 3He target, Phys. Rev. C 90, 055201 (2014)

M. Posik, et al., A Precision Measurement of the Neutron Twist-3 Matrix Element d2Hn: Probing Color Forces, Phys. Rev. Lett. 113, 022002 (2014)

J. Katich, et al., Measurement if the Target-Normal Single-Spin Asymmetry in Deep-Inelastic Scattering from the Reaction 3He(e,e')X, Phys. Rev. Lett. 113, 022502 (2014)

I. Korover, et al., Approaching the nucleon-nucleon short-range repulsive core via the 4He(e,e'pN) triple coincidence reaction, Phys. Rev. Lett. 113, 022501 (2014)

K. Allada, et al., Single spin asymmetries of inclusive hadrons produced in electron scattering from a transversely polarized 3He target, Phys. Rev. C 89, 042201 (2014)

K. Slifer, E. Long, Novel Physics With Tensor Polarized Targets, Proc. of Science PSTP2013 008 (2013)

D. Wang, et al., Measurement of parity violation in electron-quark scattering, Nature 506, 67-70 (2014)

R. Alarcon, et al., Measured radiation and background levels during transmission of megawatt electron beams through millimeter apertures, Nuclr. Instr. Meth. A, 729, 233 (2013)

D. Wang, et al., Measurement of the Parity-Violating Asymmetry in Electron-Deuteron Scattering in the Nucleon Resonance Region, Phys. Rev. Lett. 111, 082501 (2013)

M. Mihovilovič, et al., Methods for Optical Calibration of the BigBite Hadron Spectrometer, Nuclr. Instr. Meth. A 686, 20-30 (2012)

N. Ackerman, T. Atherton, W. Deconick, M. Falk, S. Garmon, E. Henry, E. Long, Gender and Sexual Diversity Issues in Physics: The Audience Speaks, arXiv:1206.4112v1 (2012)

J. Huang, et al., Beam-Target Double Spin Asymmetry ALT in Charged Pion Production from Deep Inelastic Scattering on a Transversely Polarized 3He Target at 1.4 < Q^2 < 2.7 GeV2, Phys. Rev. Lett. 108, 052001 (2012)

Z. Ahmen, et al., New Precision Limit on the Strange Vector Form-Factors of the Proton, Phys. Rev. Lett. 108, 102001 (2012)

S. Abrahamyan, et al., Search for a New Gauge Boson in Electron-Nucleus Fixed-Target Scattering by the APEX Experiment, Phys. Rev. Lett. 107, 191804 (2011)

X. Qian, et al., Single Spin Asymmetries in Charged Pion Production from Semi-Inclusive Deep Inelastic Scattering on a Transversely Polarized 3He Target, Phys. Rev. Lett. 107, 072003 (2011)

X. Zhan, et al., High Precision Measurement of the Proton Elastic Form Factor Ratio μpGE/GM at Low Q2, Phys. Lett. B 705, 59-64 (2011)

Technical Notes

E. Long, O. Rondon, P. Solvignon, Rates and Statistical Uncertainty Calculations for a Measurement of Azz, JLAB-TN-13-029.

 
 
The Deuteron Tensor Structure Function b1 experiment, E12-13-011, was approved by JLab PAC40 with an A- physics rating.