Message from Division Chair
I would like to welcome researchers interested in materials science, biology, chemistry, and high-energy physics using quantum beams (muon, neutron, proton, photon, ions, etc., of energy range keV – TeV) available in the large-scale accelerator facilities around the world to discuss their research achievements/ideas in this division. This hybrid conference – held in person at Fairmont State University, Fairmont, West Virginia, and the Central Department of Physics, Tribhuvan University, Kathmandu, Nepal, as well as online via Webex—provides a platform for young researchers to share ideas and learn from experts across multidisciplinary fields. Let’s work together to make this conference a success!
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Plenary Speaker
Nuclear Physics at the Intensity Frontier: The Role of Nepali Physicists of the MEP Group.
The medium energy group at Mississippi State University has been addressing some basic questions, such as how exactly protons and neutrons are built starting with the underlying quarks and gluons? What is the origin of quark confinement in the strong force? Are there new forces beyond the Standard Model? The MEP group has made significant contributions towards answering these questions, and Nepali physicists have played an outsize role in this effort. I will review their contribution and progress made over the last two decades in answering these questions.
Division Schedule
Please look below for detailed schedule.
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Abstract Number: ANPA2025-N00068 Presenting Author: Roshan Pudasaini Co-Authors: Amba Datt Pant; Rajendra Prasad Adhikari Presenter's Affiliation: Kathmandu University Title: Muonium behavior in protoporphyin and porphyrin: a first-principles study Location: Virtual Presentation Show/Hide Abstract There are various methods to detect low oxygen levels or hypoxia in tumor/cancer such as positron emission tomography, magnetic resonance imaging, electron paramagnetic resonance, and pulse oximetry with their limitations as mentioned by Tatum et al [1] and Conner et al [2]. A noninvasive technique is necessary to detect hypoxia and assess its existence, extent, and spatial distribution within a tumor. In order to develop a noninvasive tool for the diagnosis and treatment of cancer, we propose a muon method and detected the molecular oxygen in water and dilute protein solutions (Hb, TBS, albumin, serum)[3][4]. To interpret the muon experiment, theoretical study is necessary to understand the stopping sites and charge states of injected muon into biomolecules. In our earlier work, based on minimum potential energy, we found the stopping site of the muonium in the heme group of DeoxyHb, OxyHb, and CoHb around the nitrogen atom of the imidazole ring of histidine [5].
Muon is a like a light proton with mass around 1/9 of that of a proton. Since the muon's gyromagnetic ratio is around three times greater than that of the proton, it is highly sensitive to magnetic field in materials. Muonium(Mu) on the other hand, is bound state of a positive muon and an electron with similar chemical properties of H atom [6]. Relaxation rate of Mu due to spin exchange interaction with O2 provides the information about the existence of O2 in the solutions [7]. To understand the muon data in hemoglobin, we perform first-principles study in the protophyrin and porphyrin to estimate the stopping site and charge states of the muon. The estimated hyperfine coupling terms will be helpful to support the muon experiment in the Hb derivatives. In the program, the stopping sites and hyperfine coupling interaction of Mu in the protoporphyrin and porphyrin will be presented.
Reference:
[1] J. L. Tatum, Int. J. Radiat. Biol., 82 (2006) 699–757.
[2] J. P. O’Connor et al., Cancer Res., 76 (2016) 787–795.
[3] A. D. Pant et al., Nucl. Instrum. Methods Phys. Res. A, 1011 (2021) 165561.
[4] A. Pant et. al., Journal of Physics: Conference Series, 551 (2014) 012043.
[5] R. Pudasaini et al., Interactions, 245 (2024) 34.
[6] K. Nagamine, Introductory muon science, Cambridge University Press, 2003.
[7] A. D. Pant, J. Nepal Phys. Soc., 4 (2017) 7–10.
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Abstract Number: ANPA2025-N00075 Presenting Author: Karishma Rana Co-Authors: nan Presenter's Affiliation: Amrit Campus, Tribhuvan University Title: STUDY OF VARIATION OF ACTIVITY CONCENTRATION OF 226-Ra, 232-Th AND 40-K AND THE RADIOLOGICAL PARAMETERS THROUGH RADIOMETRIC SURVEY FROM SETIBENI TO PURTIGHAT Location: In-Person Presentation, CDP Show/Hide Abstract We have studied terrestrial radioactivity due to naturally occurring radioactive materials (NORMS) 226-Ra, 232-Th, and 40-K and some radiological parameters using the portable gamma-ray spectrometer (PGIS-2) from Setibeni to Purtighat, Nepal via the Kaligandaki corridor. The activity concentrations of 226-Ra, 232-Th, and 40-K were found to be 1202.02 Bq/kg, 91.64 Bq/kg, 83.20 Bq/kg respectively. The absorbed dose rate was found to be143.08 nGy/h, the internal hazard index was 1.07, the annual effective dose equivalent value was 0.18 mSv/year, and the excess lifetime cancer risk factor was 0.62. The result indicated that despite the higher activity concentration of 226-Ra, 232-Th, and 40-K, the study area is non-hazardous and the materials are safe to use in construction. This could be due to the high concentrations of radionuclides on the bank of the Kaligandagi River. The correlation of dose rate with the activity concentrations of 226-Ra, 40-K, and 232-Th were also plotted separately
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Abstract Number: ANPA2025-N00084 Presenting Author: Anjan Dahal Co-Authors: Amba Datt Pant; Hari Shankar Mallik; Anjan Dahal; Akihiro Koda; Katshuhiko Ishida; Burkhard Geil; Jumpei Nakamura; Shoichiro Nishimura; Hiromi Sakai; Koichiro Shimomura Presenter's Affiliation: Central Department of Physics, Tribhuvan University, Kathmandu, Nepal Title: Understanding Muonium Anisotropy in Phosphate Buffered Saline: A ?SR Study Location: In-Person Presentation, CDP Show/Hide Abstract To establish the fundamentals of muon and muonium behavior in the biological system and its application in the cancer research, muon spin relaxation and rotation (?SR) experiments are conducted in water, buffer solutions, proteins, biomacromolecules and Hemoglobin. We have conducted experiment in several bio-samples and perform DFT calculations to support the experiments. This work focuses on ?SR experiment in phosphate-buffered saline (PBS) which is a biologically relevant medium often used in the medical applications and experimental biology. Muon is like a light proton (m?~1/9 mp) but with higher magnetic moment (??~3.2?p). When the positive muon implanted in a sample it captures an electron forms a hydrogen like atom called muonium (Mu). This light muonium acts as an ultra-sensitive probe, settling at reactive molecular sites to reveal detailed information about local electronic and magnetic environments of the sample. The experiment was performed in the temperature range of 140 K to 300 K under various low magnetic fields and muonium precession signal was observed. In the liquid state of PBS, an isotropic muonium along with a diamagnetic muon were observed. However, in frozen PBS, two distinct diamagnetic muon species and an axially symmetric anisotropic muonium like in frozen water were observed. In the program temperature dependent nature of the anisotropic muonium will be presented.
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Abstract Number: ANPA2025-N00082 Presenting Author: Roshan Nepal Co-Authors: Anup Shrestha ; Anjan Dahal Presenter's Affiliation: Tribhuvan University Title: Detaction of metal oxidation states in halides using muon: a first-principle study Location: In-Person Presentation, CDP Show/Hide Abstract Metal oxidation states play an important role in determining the properties (magnetism, catalysis, ion conductivities, etc.) of wide varieties of materials. For example, in biology, O2 binding hemoglobin (oxyhemoglobin) contains Fe in ferrous states in its heme-group however the methemoglobin that cannot bind the O2 contains the ferric states of the Fe. From magnetic point of view, oxyhemoglobin shows diamagnetic nature however the methemoglobin shows the strong paramagnetic behavior. Since muon acts as a sensitive local probe, it can detect local electronic and dynamic states of materials. To understand the muon experimental data, computational technique, particularly density functional theory (DFT), is essential for revealing muon sites in the materials. Here we choose metal-halides with differing oxidation states (Fe2+ in FeCl2, Fe3+ in FeCl3, and Zn2+ in ZnCl2) to understand the behavior of muon in samples with different oxidation states. The FeCl₂ and FeCl₃ exhibit magnetic ordering [1], while the ZnCl₂ exhibits nonmagnetic [1]; consequently, the muon’s local stopping site, spin polarization, and electronic interactions vary among these compounds [2, 3]. We focus to identify and compare the muon sites and estimate its polarization in different oxidation states, and then investigate muon–metal interactions. In the program, the DFT result of muon behavior in FeCl2 and ZnCl2 will be presented.
References
[1] N. N. Greenwood, and A. Earnshaw, 2nd ed. (Chemistry of the Elements, Butterworth-Heinemann, 2012).
[2] I. J. Onuorah et. al., Phys. Rev. B, 97 (2018) 174414.
[3] S. J. Blundell and T. Lancaster, Appl. Phys. Rev. 10, (2023) 021303.
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Abstract Number: ANPA2025-N00076 Presenting Author: Surendra Hangsarumba Co-Authors: Surendra Hangsarumba, Raman Kumar Kamat, Kishori Yadav, Suresh Prasad Gupta, Prakash M. Shrestha, Saddam Husain Dhobi Presenter's Affiliation: TU IoST, Patan Multiple Campus, Patandhoka,Lalitpur Title: Radiation Shielding Properties of Waste Materials Using a Geiger-Müller Counter and Different Radioactive Sources Location: In-Person Presentation, CDP Show/Hide Abstract Radiation shielding is a crucial safety measure used to reduce exposure to harmful ionizing radiation by using materials that absorb or block radiation. Effective shielding helps protect human health, equipment, and the environment in medical, industrial, and research settings. This study evaluates the shielding properties of waste materials plastic bottles, human hair, disposable medical gloves, and cardboard against three radioactive sources: Thallium (204Tl), Cesium (137Cs), and Strontium (90Sr), with present activities 0.05 µCi, 1.125 µCi, and 0.130 µCi, respectively. Samples of each material were prepared in solid form with dimensions 3 × 4 × 0.2 cm. Using a Geiger-Müller (GM) counter (Model No: TE Np 1, 220-230V, 50 Hz) at Patan Multiple Campus, radiation counts/minute were measured with the sample placed 6 cm from the source and 4 cm from the detector window, operated at 400 V. Without shielding, the counts/minutes recorded were 38 ± 3 counts/minute with 204Tl sources , 72± 4 counts/minute with 137Cs sources, and 182± 3 counts/minute with 90Sr sources. When shielded, the counts/minute observed for the 204Tl source were with plastic bottle is 32± 3 counts/minute, human hair is 6± 3 counts/minute, gloves is 6± 3 counts/minute, and cardboard is 30± 3 counts/minute; for the 137Cs source with plastic bottle is 58 counts/minute, human hair is 12± 3 counts/minute, gloves is 12± 3 counts/minute, and cardboard is 52± 3 counts/minute; and for the 90Sr source with plastic bottle is 180± 4 counts/minute, human hair is 20± 4 counts/minute, gloves is 26± 4 counts/minute, and cardboard is 132± 4 counts/minute. The background counts/minute without sources for all direction is 13 counts/minute. This indicate that human hair and gloves significantly reduced radiation counts compared to other materials, suggesting better shielding efficiency. These waste materials, due to their composition and effectiveness, could be utilized in developing low-cost radiation protection structures in areas with high radiation exposure.
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Abstract Number: ANPA2025-N00079 Presenting Author: Bal Vikram Khatri Co-Authors: Om Prakash Niraula; Himali Kalakhety; Raju Khanal Presenter's Affiliation: Tribhuvan University Title: In-Situ Radiometric Study Along the Kaligandaki River: Focus on the Deepest Gorge and Shaligram Fossils Location: In-Person Presentation, CDP Show/Hide Abstract An in-situ radiometric survey was conducted along the stretch of the Kaligandaki River in Nepal, a region of geological significance that features the world's deepest gorge and the presence of Shaligram fossilized ammonites, which hold both cultural and scientific importance. Kaligandaki River, one of major Rivers of Nepal, originates from Damodarkund close to Lomanthang, where deposit of Uranium have been confirmed by Department of Mines and Geology, Nepal. The famous fossilized stone Shaligram is also found only in this region. To carry out the study, we used the portable gamma-ray spectrometer PGIS-2, which is equipped with a NaI(Tl) detector. We determined radiological hazard parameters associated with the radionuclides, including radium equivalent activity, absorbed gamma dose rates in the air, annual effective dose rate, external hazard index, and internal hazard index. The results showed that 238U activity ranged from 55.17 Bq kg−1 to 125.63 Bq kg−1 with mean value 83.31 ± 19.49 Bq kg−1, 232Th activity ranged from 2.28 Bq kg−1 to 144.22 Bq kg−1 with mean value 61.55 ± 31.29 Bq kg−1 and 40K activity ranged from 92.48 Bq kg−1 to 1158.06 Bq kg−1 with mean value 631.44 ± 269.95 Bq kg−1. Mean values of the activities of all three radionuclides were found to be above the world average value. Radiological parameters like Raeq, ADR, Hex and Hin were found to be 219.95 ± 72.76 Bq kg−1, 102.18 ± 33.53 nGy hr-1 0.59 and 0.82 respectively. This study underscores the importance of continuous monitoring to ensure environmental and public safety in regions with naturally occurring radioactive materials.
Keywords: PGIS-2, Hazard index, Gamma dose rate, Radiation hazard
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Abstract Number: ANPA2025-N00080 Presenting Author: Devendra Raj Upadhyay Co-Authors: Orgin Tamang; Raju Khanal Presenter's Affiliation: Central Department of Physics, Tribhuvan University, Kathmandu, Nepal Title: Radiation Shielding and Transport Characeristics of Zinc Lithium Dysprosium Borotellurite Glasses Using Theoretical and Monte Carlo Code Location: In-Person Presentation, CDP Show/Hide Abstract The radiation shielding and dose attenuation capacity of six zinc-lithium-dysprosium borotellurite glass system having composition: (B2O3)0.2-(TeO2)0.3-x(ZnO)0.28–(Li2CO3)0.2– (Dy2O3)0.02-(WO3)x labeled as W1 to W6 for x value from 0.02 to 0.12 has been analysed. Shielding parameters like mass attenuation coefficient, linear attenuation coefficient, half value layer, tenth value layer, effective atomic number are estimated. Similarly, transport properties such as effective electron density, mean free path, effective conductivity have been analysed using Phy-X/PSD database in the energy range 1 keV to 100 GeV. Furthermore, fast neutron removal cross sections were calculated. The parameters like stopping potential and projected range of ions like proton, helium, and carbon in materials were calculated using Stopping and Range of Ions in Matter (SRIM) software package application. The trajectories and effective dose rate of photon was also evaluated using Particle and Heavy Ions Transport code System (PHITS). The obtained results show that sample W6(0.2B2-O3–0.3TeO2- 0.0336ZnO–0.2Li2CO3–0.02Dy2O3–0.12WO3) has better protective potential than rest five glass samples and comparable to other glasses that were previously studied and recommended for nuclear applications.
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Abstract Number: ANPA2025-N00081 Presenting Author: Ram Sharan Karki Co-Authors: nan Presenter's Affiliation: Tribhuvan University Title: Assessment of Uncertainty in Dose Measurement Using TLD-100 and Monte Carlo Methods Location: In-Person Presentation, CDP Show/Hide Abstract This study evaluates the uncertainties in radiation dose measurements using TLD-100 dosimeters (lithium fluoride crystal doped with magnesium and titanium and the Harshaw 6600 Plus TLD reader system) at the Nepal Academy of Science and Technology, Khumaltar, Nepal. LiF:Mg,Ti is widely used in thermoluminescent dosimetry due to its favorable properties, making it a preferred material for radiation monitoring in occupational, environmental, and medical contexts. The calibration of TLD-100 dosimeters and evaluation of uncertainties are done through both analytical and Monte Carlo approaches. The standard uncertainty of personal dose equivalent Hp(10) measurements, considering non-linear response, was found to be 0.123, with an expanded uncertainty of 0.164 mSv and a relative uncertainty of 16.122% (k = 1.96), while the combined relative uncertainty for generating calibration factors was 11.91%. When employing Monte Carlo methods, the standard uncertainty increased to 0.140, with an expanded uncertainty of 0.224 mSv and a relative uncertainty of 20.919%, resulting in a combined relative uncertainty of 13.46%. These results confirm that the dosimetry system meets international uncertainty standards, and the use of Monte Carlo methods contributes to improved accuracy in occupational dose assessments.
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Abstract Number: ANPA2025-N00078 Presenting Author: Num Prasad Acharya Co-Authors: Suresh Basnet; Amar Prasad Misra; Raju Khanal Presenter's Affiliation: Mr Title: DUST-ION-ACOUSTIC SOLITARY AND SHOCK WAVES FOR SATURN’S E-RING MAGNETIZED DUSTY PLASMA WITH q-NONEXTENSIVE ELECTRON DISTRIBUTION AND DUST CHARGE FLUCTUATIONS Location: In-Person Presentation, CDP Show/Hide Abstract DUST-ION-ACOUSTIC SOLITARY AND SHOCK WAVES FOR SATURN’S E-RING MAGNETIZED DUSTY PLASMA WITH q-NONEXTENSIVE ELECTRON DISTRIBUTION AND DUST CHARGE FLUCTUATIONS
Num Prasad Acharya1,2, Suresh Basnet1, Amar Prasad Misra3 and Raju Khanal1
1Central Department of Physics, Tribhuvan University, Kirtipur, Kathmandu 44613, Nepal
2Department of Physics, Mahendra Multiple Campus, Tribhuvan University, Ghorahi 22415, Dang, Nepal
3Department of Mathematics, Visva-Bharati (A Central University), Santiniketan-731 235, India
Email: numacharya@gmail.com
Abstract
We have investigated dust-ion acoustic solitary and shock waves in a magnetized dusty plasma and explored the features of solitary and shock waves in Saturn’s E-ring’s dusty plasma, in account of anisotropic ion pressure and dust charge fluctuations. The dust charge equation has been solved via Newton’s Raphson method. The modified damped KdV and Burger’s equations have been extended and analytically solved. In the case of space dusty plasma, we have taken the physical parameters relevant to Saturn’s E-ring and both compressive and rarefactive solitary and shock waves are evolved. The features of monotonic shock waves are significantly affected by the nonextensive parameter q, magnitude of magnetic field, obliqueness of wave propagation, anisotropic ion pressure, and size of dust grain as well. Furthermore, the dust charge fluctuation rate plays a crucial role in the study of shock wave evolution on Saturn’s E-ring dusty plasma.
References:
[1] A. P. Misra, Appl. Math. Comput., 256, 368–374 (2015).
[2] S. Ghosh, J. Plasma Phys., 71, 519–526 (2005).
[3] S. Bansal, M. Aggarwal, and T. S. Gill, Phys. Plasmas, 27, 083704 (2020).
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Abstract Number: ANPA2025-N00083 Presenting Author: Anup Shrestha Co-Authors: Amba Datt Pant; Hari Shankar Mallik; Anjan Dahal; Akihiro Koda; Katshuhiko Ishida; Burkhard Geil; Jumpei Nakamura; Shoichiro Nishimura; Hiromi Sakai; Koichiro Shimomura Presenter's Affiliation: Central Department of Physics, Tribhuvan University, Kathmandu, Nepal Title: A µSR study in oxyhemoglobin aqueous solutions Location: In-Person Presentation, CDP Show/Hide Abstract A low oxygen concentration in tumor tissue is known as hypoxia, which supports the progression of the tumor and resists the treatments [1,2]. To detect hypoxia, a non-invasive muon method has been proposed [3,4], which is expected to compensate for the current unavailability of such a method [5]. The development of the proposed muon method requires an organized muon spin rotation and relaxation (µSR) study of biomacromolecules. Oxyhemoglobin (OxyHb), a hemoglobin (Hb) derivative, transports oxygen (O2) from lungs to tissues and exhibits diamagnetism. Muon is similar to a proton with a lighter mass (mµ = 1/9 mp) and greater magnetic moment (µµ = 3.2 µp). It is an exotic magnetic probe sensitive to the magnetic field in the material. Muonium (Mu), a bound state of a muon and an electron (µ+e-), is like a light hydrogen isotope and directly interacts with O2. In this study, we performed ZF- and weak TF-µSR measurements in two concentrations (114.5 g/L and 5 g/L) of aqueous OxyHb solutions (purified from human blood) at temperatures ranging from 300 K to 140 K.
Isotropic Mu in liquid and axially symmetric anisotropic Mu in frozen phase are observed via concentration-dependent studies. In the liquid phase, in addition to the paramagnetic Mu, a diamagnetic muon species (H2O-Mu+-H2O) is observed, while in the frozen phase, two diamagnetic muon species (H2O-Mu+-H2O and MuOH) are observed, like in ice [6] and buffer [7]. The observed values of the Mu hyperfine transitions are in close approximation to the theoretically predicted values.
References
[1] M. C. Brahimi-Horn and J. Pouysségur, Journal of Molecular Medicine 85 (2007) 1301–1307.
[2] A. L. Harris, Nature Reviews Cancer 2, (2002) 38–47.
[3] A. D. Pant et. al., Journal of Physics: Conference Series 551(1), (2014) 012043.
[4] A. D. Pant et. al., Nuclear Instruments and Methods in Physics Research A 1011, (2021) 165561.
[5] J. P. B. O’Connor et al., Cancer Research 76, (2016) 787–795.
[6] A. D. Pant et al., Physical Review B 110, (2024) 104104.
[7] A. Dahal et al., oral presentation in this conference.
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Abstract Number: ANPA2025-N00077 Presenting Author: Sabin Thapa Co-Authors: Ramona Vogt, Michael Strickland Presenter's Affiliation: Kent State University Title: Quarkonia as the Probe of QGP formation in High Energy Collisions Location: In-Person Presentation, Fairmont Show/Hide Abstract High-energy heavy-ion collisions at RHIC and the LHC recreate the Quark–Gluon Plasma (QGP), a deconfined state of matter present moments after the Big Bang. Heavy quarkonia — bound charm–anticharm or bottom–antibottom pairs — serve as excellent probes of the QGP medium. Quarkonia yields in such collisions are suppressed relative to proton–proton baselines due to both cold nuclear matter effects and modifications due to the interaction with the hot QGP medium. To better understand this exotic QCD state, we have to disentangle different nuclear contributions, for which we have developed a unified framework that incorporates both cold and hot nuclear matter effects, with background QGP evolution simulated using relativistic anisotropic hydrodynamics. Within this evolving medium, bottomonium suppression is computed using two complementary approaches: an openâ€quantumâ€system treatment based on pNRQCD, and a semiâ€classical rate equation with recent reaction rates. Combining all these effects, we compute the nuclear modification factor $R^\Upsilon(y,p_T)$ for different bottomoia states, comparing our results with experimental data and providing predictions for future measurements.
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