JLab Hypernuclear Collaboration Meeting 2025

May 15, 2025, 9:00 AM → May 16, 2025, 6:00 PM US/Eastern

L102 (Jefferson Lab CEBAF )

Mark Jones (Jefferson Lab), Toshiyuki Gogami (Kyoto University)

Hypernuclear Experiments at Hall C

Experiments

• E12-24-003 "Studying Lambda interactions in nuclear matter with the ²⁰⁸Pb(e,e'K⁺)²⁰⁸_ΛTl reaction" [42 PAC days]

• E12-24-004 "Study of charge symmetry breaking in p-shell hypernuclei" [24 PAC days]

• E12-24-011 "Study of a triaxially deformed nucleus using a Lambda particle as a probe" [28 PAC days]

• E12-24-013 "An isospin dependence study of the Lambda-N interaction through the high precision spectroscopy of Lambda hypernuclei"  [55 PAC days]

Run Group Experiment (Parasitic Experiment)

• E12-15-008A "High-resolution spectroscopy of light hypernuclei with the decay-pion spectroscopy"  [0 PAC days]

 

---

Objective of the Meeting 

Hyeprnuclear spectroscopy at Jefferson Lab has a unique role for investigating the baryon interactions with the strangeness degrees of freedom. We are planning to perform experiments with high reoslution spectrometers, HES and HKS, which are dedicated to hypernuclear missing-mass spectrosocpy. The experiments will measure hypernuclei with wide nuclear masses ranging from A = 3 to 208 for systematic studies to pin down various physics topics such as charge symmetry breaking (CSB), multi-body Lambda-NN interaction, hypertriton puzzle, hyperon puzzle in neutron stars, search for triaxially deformation states etc.  

In this collaboration meeting, significance and impact of the hypernuclear project at JLab will be shared and discussed. In addition, some preparation updates, aiming at the performance of experiments from 2027, will be shown. 

 

---

 

Zoom 

zoom link / ID: 161 955 1464 / PASSCODE: 841886

 

---

Other information 

• Experimental readiness review on Nov 18-19, 2024: https://hallcweb.jlab.org/wiki/index.php/ERR_Hypernuclear

• Collaboration meeting on Mar 22, 2024: https://indico.jlab.org/event/822/

• Collaboration meeting on Nov 14, 2023: https://indico.jlab.org/event/742/

 

---

Registration

As for onsite participants, please follow the guidance shown here: https://www.jlab.org/facilities/steps-registration

You can find the registration page for the meeting by clicking a registration buttun below. 

 

 

Thursday, May 15

Project Overview

Convener: Joerg Reinhold (Florida International University)

1 Opening

Speaker: Satoshi N. NAKAMURA (The University of Tokyo)

2 Lab Update and Run Schedule

Speaker: Mark Jones (Jefferson Lab)

3 Overview of the hypernuclear spectrometer system

Speaker: Liguang Tang (Hampton University/JLab)

4 Isospin dependent Lambda-NN interaction + Triaxially Deformation Nuclear States

E12-24-011 "Study of a triaxially deformed nucleus using a Lambda particle as a probe" [28 PAC days]
E12-24-013 "An isospin dependence study of the Lambda-N interaction through the high precision spectroscopy of Lambda hypernuclei" [55 PAC days]

Speaker: Satoshi N. NAKAMURA (The University of Tokyo)

10:15 AM Coffee Break

5 Research of Charge Symmetry Breaking in the Lambda-Nucleon Interaction by Electron Probe

E12-24-004 "Study of charge symmetry breaking in p-shell hypernuclei" [24 PAC days]

Speaker: Toshiyuki Gogami (Kyoto University)

6 Heavy Hypernuclear Study

E12-24-003 "Studying Lambda interactions in nuclear matter with the 208Pb(e,e'K+)208ΛTl reaction" [42 PAC days]

Speakers: Franco Garibaldi (INFN Rome), Guido Urciuoli (INFN)

7 Decay Pion Spectroscopy of Lambda Hypernuclei at Jefferson Lab

E12-15-008A "High-resolution spectroscopy of light hypernuclei with the decay-pion spectroscopy" [0 PAC days]

Speaker: Sho Nagao (The University of Tokyo)

11:50 AM Lunch Break

Invited Physics Seminars

Convener: Dr Toshiyuki Gogami (Kyoto University)

8 Lambda potential in dense nuclear matter from chiral EFT: Bridging heavy-ion collisions, hypernuclei, and neutron stars

A unified approach integrating heavy-ion collisions, other nuclear experiments, and neutron stars with the modern nuclear force
from chiral effective field theory (chiral EFT) has provided valuable insights into the properties of the equation of state of dense matter. For a microscopic description of dense matter, such an approach should be performed also for the hyperon sector, particularly for addressing the long-standing hyperon puzzle of neutron stars. In this talk, I will introduce our research on verifying the validity of the Lambda single-particle potential (Lambda potential) in dense matter calculated from the baryon force based on chiral EFT. This potential is sufficiently repulsive to avoid the hyperon puzzle. We find that the model calculations with the Lambda potential are consistent with the Lambda hypernuclear spectroscopy [1] and the Lambda directed flow [2].

[1] A. Jinno, K. Murase, Y. Nara, and A. Ohnishi, Phys. Rev. C 108 (2023) 065803.
[2] Y. Nara, A. Jinno, K. Murase, and A. Ohnishi, Phys. Rev. C 106 (2022) 044902.

Speaker: Asanosuke Jinno (Kyoto University)

9 Role of Hyperon Interactions in Neutron Stars and Supernova Cores

The presence of hyperons in high-density astrophysical environments, such as supernova cores and neutron stars, significantly affects their equation of state (EoS) and overall structure. At extreme densities and temperatures, hyperons are expected to emerge, softening the EoS and influencing the evolution of (proto) neutron stars. However, this softening leads to the so-called hyperon puzzle, which refers to the challenge of reconciling hyperon-rich EoS with observations of two-solar-mass neutron stars. Understanding the role of hyperon interactions is therefore crucial for constructing a realistic EoS applicable to both neutron stars and core-collapse supernovae.
In this study, we investigate the role of two-body and three-body forces acting on \Lambda hyperons in the dynamical core-collapse simulations of massive stars as well as in neutron stars. We analyze how these interactions influence the dynamics of collapsing massive stars and the hyperon fraction in supernova cores. Our results systematically examine the impact of uncertainties in hyperon interactions on astrophysical phenomena and explore the potential for observations to provide constraints on these interactions.

Speaker: Dr Hajime Togashi (Research Center for Nuclear Physics, Osaka University, Japan)

2:10 PM Coffee Break

Overview of Spectroscopy System

Convener: Dr Ralph Marinaro (Christopher Newport University)

10 Overview of HES-HKS System and Commissioning Plan

Speaker: Dr Toshiyuki Gogami (Kyoto University)

11 Overview of ENGE System and Commissioning Plan

Speaker: Dr Sho Nagao (The University of Tokyo)

Friday, May 16

Preparation Status and Discussion

Conveners: Dr Bishnu Pandey (Virginia Military Institute), Dr Sho Nagao (The University of Tokyo)

12 Test plan for wire chambers at ESB

Speaker: Liguang Tang (Hampton University/JLab)

13 New Water Cherenkov Detector for Proton Rejection

Speaker: Mr Kaito Higashimoto (The University of Tokyo)

14 Cosmic-Ray Test of Aerogel Cherenkov Counters by FADC

Speaker: Mr Teppei Iwamoto (Kyoto University)

15 HES-HKS simulation

Speaker: Mr Ravindu Kumaragamage (Hampton University)

16 HES-HKS simulation

Speaker: Mr Tatsu Ishige (Tohoku University)

10:15 AM Coffee Break

17 Scintillation Fiber Detector Used for Focal Plane Detection in ENGE

Speaker: Mr Kotaro Nishi (The University of Tokyo)

18 Radiation Tolerance Test for ENGE Fiber Detector

19 Time-Of-Flight Detector for ENGE

Speaker: Mr Ken Nishida (The University of Tokyo)

20 Radiation Simulations By Geant4 and FULKA

Speaker: Mr Jin Takahashi (The University of Tokyo)

11:40 AM Lunch Break

Preparation Status and Discussion

Conveners: Guido Urciuoli (INFN), Pete Markowitz (Florida International University)

21 Engineering for Hypernuclear Spectrometer System

1. Floor plan and design overview (locations/supports-platforms/shielding),
2. Design and construction status/plan (including sieve slits/collimators and target ladder extraction/Enge vacuum box),
3. PS/LCW checklist and plan,
4. Cable routing,
5. Stray field calculation (issue/solution/result),
6. Installation plan/estimated timeline

Speakers: Jamie Shiflett, Steven Lassiter (JLab)

22 Target System for Hypernuclear Spectroscopy

Speaker: David Meekins (Jefferson Lab)

23 Hall C Beamline + SLI Overview

Speaker: Dave Gaskell (Jefferson Lab)

2:45 PM Coffee Break

24 DAQ System and Preparation Plan

Speaker: Alexandre Camsonne (Jefferson Laboratory)

25 Online and Offline Analysis Software

26 ePass Policy and List of Required Documents

Speaker: William Henry (Jefferson Lab)

27 Free discussion

28 Closing

Speaker: Satoshi N. NAKAMURA (The University of Tokyo)