2022 Frontiers and Careers in Nuclear and Hadronic Physics

Aug 4, 2022, 9:00 AM → Aug 7, 2022, 4:00 PM US/Eastern

26-414 (MIT Laboratory for Nuclear Science)

Farah Afzal, Jackson Pybus (MIT)

The Frontiers and Careers (F&C) is a workshop for Ph.D. students and postdoctoral researchers, and will precede the 2022 Gordon Research Conference on Photonuclear Reactions.

The 2022 F&C will continue to provide Ph.D. students and postdoctoral researches in the field of electromagnetic-interaction physics a place to discuss and present their research, explore career prospects, and make professional connections, all with the express purpose of preparing themselves for their future careers.

The workshop will take place in-person at the MIT Laboratory for Nuclear Science. Detail about available lodging will be added soon.

Thursday, August 4

3:00 PM → 7:00 PM Check-in

Friday, August 5

9:00 AM → 9:45 AM Breakfast

9:45 AM → 10:00 AM Welcome

Speakers: Farah Afzal, Jackson Pybus (MIT)

FandC2022_WelcomeTalk.pdf

10:00 AM → 10:30 AM Pedagogical talk- Presenting data

Speaker: Lawrence Weinstein

DataVisualization2022.pdf

DataVisualization2022.pptx

10:30 AM → 11:00 AM Pedagogical talk- How to write Grant proposals?

Speaker: Evangeline Downie (George Washington University)

EJDownie_GrantProposals.pdf

11:00 AM → 11:30 AM Coffee Break

11:30 AM → 12:00 PM Academic career in the US

Speaker: Bill Briscoe (GWU)

Briscoe_FandC_2022.pdf

Briscoe_FandC_2022.pptx

12:00 PM → 12:30 PM Academic career in the EU

Speaker: Reinhard Beck (University of Bonn)

Research Careers.pdf

12:30 PM → 1:30 PM Lunch

1:30 PM → 2:00 PM Career perspectives in a Lab

Speaker: Dr Douglas Higinbotham (Jefferson Lab)

CareersAtNationalLabs.pptx

2:00 PM → 2:30 PM Career perspectives in the Industry

Speaker: Kalyan Allada

DS_Careers_talk_MIT.pdf

2:30 PM → 3:00 PM Panel discussion

3:00 PM → 3:30 PM CV session I

Speaker: Dr Douglas Higinbotham (Jefferson Lab)

CVandInterviews.pptx

3:30 PM → 4:00 PM Coffee Break

4:00 PM → 4:20 PM CV session II

4:20 PM → 6:00 PM Proton radius puzzle

Convener: Jackson Pybus (MIT)

4:20 PM Deuteron Charge Radius Experiment (DRad) at Jefferson Lab

High precision muonic deuterium spectroscopic measurements found a significantly smaller (7$\sigma$) deuteron charge radius compared to the CODATA recommended value, creating the ``deuteron charge radius puzzle''. In order to investigate this, the DRad experiment (Jefferson Lab PR12-20-006) was proposed to measure the $e-d$ elastic scattering cross section in a very low momentum transfer squared region ($\rm{Q}^2 = 2\times10^{-4} - 5\times10^{-2}~\rm{(GeV/c)}^2$), with a sub-percent proposed precision. The designed setup of the experiment will be largely based on that of the PRad-II experiment (Jefferson Lab PR12-20-004), with an addition of a low energy silicon-based cylindrical recoil detector within the windowless gas flow target cell for the suppression of the quasi-elastic background. The absolute $e-d$ elastic scattering cross section will be normalized to that of the well-known Moller scattering process, which will be measured simultaneously within similar kinematics and detector acceptances. In this talk, we will present the design of the experimental setup, related studies, and preliminary projected results.

Speaker: Jingyi Zhou (Duke University)

DRad_JZ_Frontier202208.pdf

4:40 PM Two photon exchange at Jefferson Lab

Two photon exchange (TPE) and the larger class of hadronic box diagrams can be a significant radiative correction to lepton scattering and beta decay measurements. Notably, it has been hypothesized that TPE could be responsible for the proton form factor ratio discrepancy. However, these diagrams remain difficult to calculate without large uncertainty and model-dependence, and theoretical calculations of some observables sensitive to TPE are in disagreement with experimental results. Extending experimental measurements of complementary TPE observables can provide critical benchmarks for these calculations. I will summarize recent and future TPE measurements at Jefferson Lab, including those that would be made possible by the proposed addition of a positron source to Jefferson Lab’s accelerator facility.

Speaker: Tyler Kutz (MIT/GW)

kutz_jlab_positron_FC.pdf

5:00 PM Soft-photon radiative corrections to the e^− p→e^−p l^− l^+ process

We calculate the leading-order QED radiative corrections to the process e^− p→e^− p l^− l^+ in the soft-photon approximation, in two different energy regimes which are of relevance to extract nucleon structure information. In the low-energy region, this process is studied to better constrain the hadronic corrections to precision muonic hydrogen spectroscopy. In the high-energy region, the beam-spin asymmetry for double-virtual Compton scattering allows us to directly access the generalized parton distributions. We find that the soft-photon radiative corrections have a large impact on the cross sections and are therefore of paramount importance to extract the nucleon structure information from this process. For the forward-backward asymmetry, the radiative corrections are found to affect the asymmetry only around or below the 1% level, whereas the beam-spin asymmetry is not affected at all in the soft-photon approximation, which makes them gold-plated observables to extract nucleon structure information in both the low- and high-energy regimes.

Speaker: Niklas Keil (JGU Mainz)

Soft-photon radiative corrections to the e^− p→e^−p l^− l^+ process.pdf

5:20 PM Experimental Inputs to the Hadronic Light-by-Light Contribution to the Anomalous Magnetic Moment of the Muon from BESIII

Despite being one of the most precisely studied observables in particle physics, there remains a discrepancy of 4.2$\sigma$ between the average value of the most recent direct measurements and the prediction within the Standard Model of the anomalous magnetic moment of the muon $a_\mu= (g−2)_\mu/2$. The precision of the prediction is limited by the knowledge of the hadronic contributions, which cannot be determined perturbatively, but depend on input from experiments. One of these contributions is the hadronic Light-by-Light scattering, which depends on the knowledge of transition form factors of light pseudoscalar, scalar, axial, and tensor mesons as well as the coupling of multi-meson systems to two photons, which is accessible in e$^+$e$^-$ collisions.

The BESIII experiment, operated at the BEPCII accelerator in Beijing, China, has collected the world’s largest data sets of e$^+$e$^-$ collisions in the $tau$-charm region between 2 GeV and 5 GeV. The data are ideally suited to measure the momentum dependence of transition form factors at space-like momentum transfers of $Q^2 \approx $1 GeV$^2$, which is of special relevance in the context of $a_\mu$. In this presentation we discuss recent results, ongoing projects, and future prospects of the measurements at the BESIII experiment.

Speaker: Max Lellmann (Johannes Gutenberg-Universität Mainz)

220805_FNC_PDF_Dingens.pdf

5:40 PM Small Angle Initial State Radiation Analysis of the Pion Form Factor at BESIII

The anomalous magnetic moment of the muon $a_\mu=(g_\mu-2)/2$ is one of the most precisely measured variables in modern physics. However, there is a discrepancy of $4.2$ standard deviations between the Standard Model (SM) prediction and the experimental average of the latest direct measurements at BNL and FNAL, known as the Muon $(g-2)$-puzzle. For the SM prediction the main uncertainty arises from hadronic contributions and can be improved systematically using measurements of hadronic cross sections at $e^+ e^-$ colliders. One of the most important processes is $e^+ e^- \rightarrow \pi^+ \pi^-$. Using a data set of $3.2\,$fb$^{-1}$ at a center of mass energy of $4.18\,$GeV, the $\pi^+ \pi^-$ cross section is measured at the BESIII experiment located at the BEPCII collider in Beijing, exploiting the initial state radiation technique at small angles. This analysis aims to determine the pion form factor at masses above $0.8\,$GeV, which is also interesting for hadron spectroscopy.

Speaker: Ms Yasemin Schelhaas (JGU Mainz)

F&C_YSchelhaas.pdf

6:30 PM → 10:00 PM Workshop dinner

Saturday, August 6

8:30 AM → 9:00 AM Breakfast

9:00 AM → 11:00 AM EMC effect, SRC

Convener: Jackson Pybus (MIT)

9:00 AM New Measurements of the EMC Effect at 12 GeV

Since the discovery of the EMC Effect nearly 40 years ago, there has been significant theoretical and experimental effort dedicated to understanding its underlying cause. However, to this day, the EMC Effect remains one of the great unsolved mysteries in nuclear and particle physics. Questions such as whether the EMC Effect implies that nucleon form factors are modified in nuclei or if the effect can even be explained within the framework of the conventional nucleon-meson treatment of nuclear physics highlight the importance of understanding this phenomenon.

I will provide some background on the EMC Effect and discuss its connection with Short Range Correlations (SRCs). I will then focus on how, by utilizing the upgraded 12 GeV beam at Jefferson Lab (JLab), we will make a significant contribution to the global set of EMC Effect data, improving on existing JLab measurements. This includes extending extraction of EMC ratios out to larger Q2 and Bjorken x, as well as making additional measurements of many new nuclei, especially light nuclei that are well understood and amenable to comparison with exacting theoretical calculations.

Speaker: Cameron Cotton (University of Virginia)

New_Measurements_of_EMC_at_12GeV.pdf

New_Measurements_of_EMC_at_12GeV.pptx

9:20 AM Testing the EMC-SRC Hypothesis with the BAND Experiment

The EMC effect, the observation that Deep Inelastic Scattering (DIS) from bound nucleons differs significantly from that on free nucleons, has puzzled nuclear physicists for nearly forty years. A potential cause for this phenomenon is the formation of short-range correlations (SRCs) between nucleons within a nucleus, which can lead to significant changes in partonic structure. This hypothesis can be directly tested using the technique of recoil-tagging, in which the detection of the correlated spectator nucleon can reveal that the struck nucleon was part of an SRC. The Backward Angle Neutron Detector (BAND) was designed to tag recoiling neutrons in DIS on protons bound in deuterium. BAND was installed as part of the of the CLAS12 spectrometer in Hall B of Jefferson Lab and took production data in 2019-2020. This talk will discuss the current status of the BAND analysis, whose results will further our understanding of the relationship between the EMC Effect and short-range correlations in nuclei.

Speaker: Sara Ratliff

Frontiers and Careers 2022.pdf

9:40 AM Measurements and Simulations of (e,e’n)/(e,e’p) in the Proton-Rich Nucleus 3He

Recent data mining analyses from the CLAS experiment at Jefferson Lab have enabled detection of neutrons from the hard break up of Short-Range Correlated (SRC) pairs, leading to the observation that protons are disproportionately represented in high momentum states in neutron-rich nuclei. Here we seek to determine whether neutrons speed up in proton-rich nuclei by studying the proton-rich nucleus 3He using data from the CLAS eg2 experiment. This talk will present 3He(e,e'n)/3He(e,e'p) ratios in the mean field and in the short-range correlated pair regime, with comparisons to theoretical predictions in the Plane-Wave Impulse Approximation using 3-body spectral functions.

Speaker: Erin Seroka (The George Washington University)

seroka-frontiers-e2a.pdf

10:00 AM SRC Scaling Below the Inclusive Limit

Nearly all measurements of SRC are done at high xB. Using new analysis methods and semi-inclusive data, we can extend our kinematic range to low xB.

Speaker: Andrew Denniston (MIT)

Denniston_Andrew.pdf

10:20 AM Neutron-Proton Pair Dominance of SRC pairs with a Real Photon Beam

Short Range Correlations (SRCs) are a feature of the internal structure of all
types of nuclei. Characterized by their relative and center of mass momenta,
SRC pairs have been well studied with quasi-elastic electron scattering
experiments. The reliance on electron scattering however, makes it difficult
to assess the influence of reaction effects and final state interactions on
what has been learned so far about SRCs. For that reason, the Hall D Short
Range Correlations Experiment was conducted at Jefferson Lab in Fall 2021
using a real photon beam incident on nuclear targets to explore SRCs
through various photoproduction channels, providing insight into different
kinematic regions and different final states. Our preliminary analysis shows
that the predictions of Generalized Contact Formalism (GCF) work well for
photoproduction. In my analysis, I have considered (γ p ,ρ⁰ p)
photoproduction from protons participating in SRCs as a tool for testing the
correlations’ isospin structure, in order to verify the predominance of np-
pairing observed in electron scattering. Preliminary results of testing np-pair
dominance along with comparisons to GCF will be presented in this talk.

Speaker: Phoebe Sharp (George Washington University)

Sharp_F&Ctalk.pdf

10:40 AM Preliminary results of Short-Range Correlations study in exotic nuclei at R3B

Short Range Correlations (SRC) are pairs of strong interacting nucleons with high relative momentum and low center of mass momentum compared to the Fermi momentum. The R3B S522 experiment run in 2022 at GSI, Germany and studied SRCs in the 12C and 16C isotopes, via the scattering of high energy ion beams off proton target in inverse kinematics. Using an exclusive measurement, we study for the first time SRC properties in exotic short lived nuclei, including their pair ratio and momentum distributions, paving the way for studying SRC physics in a neutron-rich environment. In this talk I will overview the experiment, discuss the calibration of several detectors and present the preliminary analysis results.

Speaker: Hang Qi (MIT)

GSI_talk.key

GSI_talk.pdf

11:00 AM → 11:30 AM Coffee Break

11:30 AM → 12:30 PM Neutron magnetic form factor

Convener: Jackson Pybus (MIT)

11:30 AM Performance of the BigBite Calorimeter during SBS-GMn Experiment

Nucleon elastic form factors help us understand the nucleon structure by probing their four-current distribution. But very little is known of neutron's magnetic form factor, $G^{n}_{M}$, for $Q^2 > 4$ $(\text{GeV}/\text{c})^2$. To shed some light in this area, an experiment, SBS-$G_M^n$ (E12-09-019), has run in Jefferson Lab's experimental Hall A from October 2021 to February 2022 and recorded data for several high precision measurements of $G_M^n$ in the range $3ratio" method. Systematic errors are greatly reduced by the use ofratio" method in which $G_M^n$ is extracted from the ratio of neutron-coincident to proton-coincident quasi-elastic electron scattering from deuteron. Upgraded BigBite Spectrometer (BB) is being used to detect scattered electrons and the new Super BigBite Spectrometer (SBS) is being used to detect both neutrons and protons. In this talk, I will present an overview of the experiment and the progress of data analysis including the offline calibration of detectors.

Speaker: Provakar Datta (University of Connecticut)

F&C_MIT_gmn&bbcal_2022.pdf

11:50 AM Design, Calibration, and Performance of a Segmented, Sampling Hadron Calorimeter Employed in the Super BigBite Spectrometer

During the first experiment (GMn) using the Super BigBite Spectrometer in experimental Hall A at Jefferson Lab, elastic proton and neutron cross sections were measured using a high timing and position resolution hadron calorimeter as the hadron arm of the spectrometer. The design of the calorimeter emphasizes precision timing and position measurements over energy resolution expecting a clean selection of elastic hadrons from reconstructed scattered electrons in the electron arm BigBite. This talk will review the design of the SBS Hadron Calorimeter (HCal) and present data from GMn, which will include necessary calibrations and preliminary in-beam resolution results.

Speaker: Sebastian Seeds (UConn)

Frontiers HCal Talk 8_6_22.pdf

12:10 PM GRINCH Gas Cherenkov Detector for SuperBigbite Spectrometer, Jefferson Lab

The GRINCH is a new heavy gas chereknov threshold detector developed for the Super Bigbite (SBS) program in Hall A in Jefferson Lab. The purpose of the GRINCH is to distinguish between pions and electrons during electromagnetic form factor scattering experiments in the SBS program. Consisting of 510 1-in photomultipier tubes and filled with $C_4 F_8 O$ heavy gas, this novel detector is designed to run in very high background rates. The GRINCH began commissioning with beam during the $G^n_M$ experimental run in Hall A in January 2022. This talk will give an overview of the GRINCH detector, analysis of its performance during the commissioning period using cluster finding methods, and its future in Hall A experiments.

Speaker: Maria Satnik (William & Mary)

Satnik_Careers_and_Frontiers_2022.pdf

12:30 PM → 1:30 PM Lunch

1:30 PM → 3:30 PM Hadron spectroscopy

Convener: Farah Afzal

1:30 PM Determination of the polarization observables T,P and H in the reaction $\gamma p \rightarrow p \pi^0$

It is experimentally and theoretically challenging to determine the exact number of exited nuclear states and their properties, since the short lifetime of these exited states leads to strongly overlapping resonances. Using a polarized beam, a polarized target or using the polarization of the recoil nucleon helps to measure single or double polarization observables, finding an unambiguous partial wave analysis solution.\
The CBELSA/TAPS experiment in Bonn provides a polarized photon beam as well as a longitudinally or transversely polarized target, allowing for the determination of single and double polarization observables. The Crystal Barrel (CB) calorimeter, together with the MiniTAPS calorimeter in forward direction, give the opportunity for close to $4\pi$ coverage for the measurements.\
In this talk I will present the determination of the polarization observables T, P and H, for energies between $600MeV$ and $3200MeV$, using data collected after the recent upgrade of the CB calorimeters readout electronics and compares these results with previous data and model predictions.

Speaker: Sebastian Ciupka (University of Bonn)

talk.pdf

1:50 PM Experimental study of polarization observables in pi0 and eta photoproduction off quasifree nucleons

The excitation spectrum of the nucleon is an important testing ground for quantum chromodynamics in the regime where it cannot be treated perturbatively. During the last two decades much progress has been made on the theory side, e.g. lattice gauge methods, and in experiments, particularly using energy tagged photon beams at electron accelerators, which has now reached a state where not only differential cross sections but also asymmetries measured with polarized photons and polarized targets allow for detailed partial wave analyses. This provides much more stringent information about the involved reaction multipoles and thus the contributing nucleon resonances.
The present experiment was done at the ELSA accelerator in Bonn with the CBELSA/TAPS detector setup. The incident electron beam of $3.2$ GeV impinged on a diamond radiator where it produced coherent bremsstrahlung photons with linear polarization, which again impinged on a transversely polarized, deuterated butanol target. This allows the simultaneous measurement of the polarization observables $\Sigma$, $T$, $P$, and $H$. Analyzed were the final states $\pi^0 N$ and $\eta N$ with the almost $4\pi$ covering electromagnetic calorimeter CBELSA/TAPS.
One of the main motivations of this experiment was a more detailed investigation of the not yet understood narrow structure in the excitation function of the $\eta n$ reaction at approximately $1$ GeV.

Speaker: Nicolas Jermann (University of Basel)

2022-08-04_Talk_Jermann_Frontiers_and_Careers.pdf

2:10 PM Feasibility Study of Λd Elastic Scattering in Data From Photoproduction Off Deuteron

Experimental observables of Λ-deuteron (Λd) elastic scattering are expected to provide unique and independent constraints on several poorly-known dynamical parameters of the hyperon-nucleon interaction, such as the ΛN spin-triplet scattering length and the ΛNN three-body force. Currently, there are no Λd experimental data. In this work, we present a feasibility study of Λd elastic scattering using the high-luminosity Jefferson Lab experiment E06-103, in which a real-photon beam was incident on a 40-cm long liquid deuterium target. The data were taken with the CEBAF Large Acceptance Spectrometer (CLAS) housed in Hall B. After photoproduction off a deuteron, a Λ beam scatters elastically off another deuteron. By detecting the final-state deuteron, and the proton and pion from Λ decay, reconstruction of the scattered and beam Λ invariant masses and reaction selection was possible. Our analysis shows that the data set contains about 4000 Λd elastic events, covering Λ beam momenta between 600 MeV/c and 1000 MeV/c and Λ center-of-mass cos(theta) between -0.6 and +0.8. Thus, for the first time, the Λd elastic differential and total cross sections will be extracted.

Speaker: Brandon Tumeo (University of South Carolina)

LambdaDeaut_Elastic_FrontiersCareers.pdf

2:30 PM Measuring CLAS12 deuterium pion electro-production cross sections for e4nu

Neutrino scattering experiments rely on neutrino event generators such as GENIE. Theoretical models used by GENIE have high uncertainties, so we will compare events from e-GENIE, an electron event mode of GENIE, with experimental electron scattering data. The goal of this project is to measure the deuterium pion electro-production cross sections in CLAS12. We will compare these cross sections to e-GENIE productions which should constrain models in pion electro-production events.

Speaker: Caleb Fogler

Fogler_Frontiers_Talk.pdf

2:50 PM φ meson photo-production at 9 GeV on nuclear targets at GlueX

The φ meson is unique to study QCD in non-perturbative region due to the
almost pure strange content. The SRC/CT experiment with GlueX detector
offers a good opportunity to study the its photo-production at 9 GeV, where
the data was limited previously. I will introduce the physics motivation,
experiment configurations and preliminary analysis results of this topic.

Speaker: Bo Yu (Duke University)

Frontiers_BoYu.pdf

3:10 PM Spectroscopic analysis of exotic hadrons using effective theories

Tetraquark states are classified using the $SU(6)_{sf}$ spin-flavor symmetry and Young tableau technique. Further, by using the extension of Gursey-Radicati mass formula, masses of tetraquark states are predicted upto good level of accuracy. Also, Decay channels and decay widths of tetraquark states are calculated and found to be in good agreement with the experimental and available theoretical data.

Speaker: Ankush Sharma (Reseach Scholar)

3:30 PM → 4:00 PM Coffee Break

4:00 PM → 5:20 PM Mixed topics

Convener: Farah Afzal

4:00 PM Exploring proton in-medium modifications through polarization-transfer measurements

Knowledge of whether the proton’s electromagnetic (EM) structure changes when it is bound inside an atomic nucleus is important for a better understanding of nuclear matter and its behavior. If such change is present it is expected to be relatively small and therefore difficult to experimentally determine[1,2].
A measurement of the polarization transfer in A(⃗e,e′p⃗) reaction is a proven technique for the extraction of EM information about the protons. For free protons (A = 1H) the ratio of the transverse to longitudinal polarization-transfer components is proportional to their electromagnetic form factor (FF) ratio GE/GM[3]. Since a similar dependence on is expected for bound protons, a comparison of results for free and bound proton might unveil useful information on their in-medium modification. However, it is often impossible to experimentally distinguish changes in proton EM structure from other nuclear effects such as final state interactions (FSI) and, therefore, inputs from theory are needed.
Experiments searching for in-medium modification of EM FF ratio were carried out on protons from different nuclei (2H, 4He, 12C, 16O)[4-9]. Although the observed polarization transfer ratios deviated significantly (especially for those with higher Fermi momenta) from those of free proton, these differences could be accounted for with the inclusion of different nuclear effects. Furthermore, despite a wide range of nuclear densities covered by these nuclei, we observed that deviations in the measured polarization ratios from those of free-proton scattering have a similar dependence on virtuality (a measure of proton’s off-shellness).
In our last two experiments, instead of comparing results between different nuclei or against a free-proton scattering, we decided to compare polarization transfer to protons extracted from different shells of a chosen target nucleus (12C[10] and 40Ca). This was motivated by theoretical predictions that local nuclear densities experienced by protons from different shells can differ significantly (e.g., approximately by a factor of two for s and p shell of 12C[11]), which could lead to observable changes in the proton EM FF ratio. We will present these new data and whether the universal behavior of polarization ratios as a function of virtuality, seen from different nuclei, is preserved.

[1] F. Close, Nuclear Physics A 446, 273 (1985).
[2] I. Sick, Nuclear Physics A 434, 677 (1985).
[3] A. Akhiezer and M. Rekalo, Sov. J. Part. Nucl. 4, 277 (1974).
[4] S. Malov, K. Wijesooriya et al., Phys. Rev. C 62, 057302 (2000).
[5] S. Strauch, S. Dieterich et al., Phys. Rev. Lett. 91, 052301 (2003).
[6] B. Hu, M. K. Jones, P. E. Ulmer et al., Phys. Rev. C 73, 064004 (2006).
[7] M. Paolone, et al. (E03-104 Collaboration), Phys. Rev. Lett. 105, 072001 (2010).
[8] I. Yaron, D. Izraeli et al., Physics Letters B 769, 21 (2017).
[9] D. Izraeli, I. Yaron, B. Schlimme et al., Physics Letters B 781, 107 (2018).
[10] T. Kolar et al. Physics Letters B 811, 135903 (2020)
[11] G. Ron et al., Phys. Rev. C 87, 028202 (2013).

Speaker: Tim Kolar

CEEP-Frontiers22-talk.pdf

4:20 PM Pion parton distribution functions within a light-front wave function approach

Pion parton distribution functions have been achieving most interest among hadronic physicists in this years; nevertheless there are still few models that use a light-front wave function (LFWF) approach for the pion.
Our theoretical model is based on the pion-state decomposition in terms of different Fock state components. In particular, we focused on the lowest number of partons constituting the pion state: 2 partons (quark-antiquark), 3 partons (quark-antiquark-gluon) and 4 partons (quark-antiquark-gluon-gluon & quark-antiquark-sea). Since the pion states enter directly in the definitions of all the parton distribution functions, these last can be re-written as overlaps of LFWFs.
Our model permits to parameterize different types of parton distribution functions, for example the collinear parton distribution functions (PDFs), the transverse momentum dependent parton distribution functions (TMDs) and the pion form factor (FF). The flexibility of the model permits to perform separate fits, providing complementary information about the internal structure: one fit for the collinear part (PDFs) and another fit for the transverse-direction dependent parameters. The latter can be performed for the pion FFs or for the pion TMDs. The idea is to perform one of these two fits and to use the best-fit parameters to predict the trend of the other, and vice-versa, in order to provide a double corss check in the transverse direction.

Speaker: Simone Venturini (University of Pavia)

Talk_Venturini.pdf

4:40 PM Diquarks in Nuclei: QCD effects in Nuclear Physics

Speaker: Jennifer Rittenhouse West (Berkeley Lab and the EIC Center at Jefferson Lab)

jrw-MIT-2022.pdf

5:00 PM An overview of the MOLLER experiment at Jefferson lab

The MOLLER experiment purposes to carry out a precise measurement of the parity-violating asymmetry from electron-electron scattering in Hall A at Jefferson lab. The measured asymmetry will be used to extract the weak charge of the electron with unprecedented precision, which in turn results in an ultra-precise determination of the weak mixing angle. The measurement precision allows us to search for new physics signatures beyond the standard model, with a sensitivity unlikely to be matched by any experiment measuring a flavor- and CP-conserving process over the next decade. In this talk, I will give an overview of the MOLLER experiment.

Speaker: Devi Adhikari (Virginia Tech)

FnC_DAdhikari_Aug_6_2022.pdf

6:30 PM → 7:50 PM Duck Boat tour

Sunday, August 7

10:30 AM → 11:00 AM Check-out

2:00 PM → 4:00 PM Bus transfer to GRC