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...
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,...
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...
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...
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...
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.
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...
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...
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...
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...
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...
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...
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.
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 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...
