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What Are the Causes of Super Flare Productivity of Solar Active Regions
Abstract:
Solar active regions (ARs) are the main sources of solar flares. Flare productivity varies among ARs, but the physical processes determining the flare activity of an AR are not clear. In this study we compared the evolution of super flare productive and low flare productive ARs. We selected 20 ARs of contrasting flare activities and sunspot sizes. Though the magnetic flux emergence is important, our study shows that it alone is not sufficient to increase the flare productivity of an AR. The new emergence can lead to either the interaction of like or opposite magnetic fluxes of non-conjugate pairs (magnetic poles not emerging together as a conjugate pair, as in a bipolar configuration). In the former case, the overall magnetic configuration remains simple and the flare productivity of AR does not change with emergence. In the latter case, the convergence of opposite magnetic fluxes of non-conjugate pairs results in a complex magnetic configuration with long polarity inversion line (PIL). Our case study of AR 11429 and other ARs shows that the persistent shearing motion and flux cancellation along such PIL results in repetitive homologous solar eruption. Further, our study suggests that length of PIL is the best magnetic-field parameter to reflect the flare productivity.
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Abstract Number: ANPA2023-N0006 Presenting Author: Keshab Chaudhary Presenter's Affiliation: Central Department of Physics, Tribhuvan University Title: A Study of Dust Properties nearby Pulsar PSRJ0856-6137 Using Iris and Akari Surveys Location: Central Department of Physics, T.U., Nepal Show/Hide Abstract We have conducted a detailed analysis of the dust structure around PSR J0856-6137 in the far infrared band by using Sky View Virtual observatory in two surveys: IRIS (60 μ m and 100μ m) and AKARI (90μm  and 140μm) survey. We have studied different physical properties such as dust color temperature, dust mass, and Planck’s function. The maximum and minimum temperature was found to be 24.815 ± 0.008K, 23.899 ± 0.008K and 27.759 ± 0.016K, 26.178 ± 0.016K in the IRIS and the AKARI surveys respectively. In both cases, the offset temperature was obtained less than 2 k. The average dust mass was found to be 1.341×1027 kg and 1.460 ×1025 kg in the IRIS and the AKARI surveys respectively. We found a small offset temperature, which suggests that the system is in a state of thermal equilibrium. We conducted a comparison of these physical parameters and found similar results to those of earlier research. This research can aid in comprehending the evolution of the pulsar.
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Abstract Number: ANPA2023-N0007 Presenting Author: Lok Nath Sharma Presenter's Affiliation: Patan Multiple Campus, IOST, Tribhuvan University, Nepal Location: Central Department of Physics, T.U., Nepal Show/Hide Abstract Magnetic reconnection between Interplanetary Magnetic field (IMF) and magnetosphere allows solar wind to penetrate into Earth, generating geomagnetic storms. In this work, we investigate the effects of the storm of 23rd April 2023 into middle and low latitudes using geomagnetic field data from 5 Intermagnet ground stations. We look for possible connection with physical parameters from OMNIWeb data at 1-min resolution through cross-correlation analyses. The horizontal components of the Earth’s magnetic field show correlation with IMF parameters (By and Bz) of 0.72 and 0.96, respectively, with a time-lag up to 20 minutes, depending on station.
Keywords: Interplanetary magnetic field (IMF), solar wind, cross correlation, magnetosphere, horizontal components of the Earth’s magnetic field
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Abstract Number: ANPA2023-N0009 Presenting Author: Prakash Man Shrestha Presenter's Affiliation: Patan Multiple Campus, IoST, TU, Nepal Title: Temporal variation of Atmospheric Ozone over Kathmandu Valley Location: Central Department of Physics, T.U., Nepal Show/Hide Abstract The main aim of this project is to study temporal the variation of atmospheric ozone over Kathmandu Valley (27.72o N, 85.32oE, 1350 m asl). The daily data of Total Ozone column (TOC) is received from
OMI satellite of NASA for 11 years of solar cycle-24 (2008 to 2018). The monthly, seasonal and annual variations of TOC are studied. The maximum value of monthly average of TOC is found 282 ± 8 DU in April, while the minimum value is found 252 ± 7 DU in December. The results also shows that TOC is seasonal dependent with larger value of TOC 174 ± 10 DU in pre monsoon and lower value of 258 ± 5DU in post monsoon. The annual average of TOC exhibits slightly variable with a maximum 280 ± 15 DU in 2015 and minimum 249 ± 10 DU in 2009. The average value of TOC during the whole study period is found 267 ± 17 DU, which indicates a good amount of stratospheric ozone content over Kathmandu Valley. Continuous wavelet transform (CWT) is also used to analysis variation of TOC. The power density of TOC 25000 DU2 is recorded from 2010 to mid of 2011 and 2015 to end of 2017. This research work is beneficial for the further identification and analysis of TOC at different places with same geography.
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Abstract Number: ANPA2023-N00010 Presenting Author: Puranjan Kafle Presenter's Affiliation: Western Regional Campus,Pokhara Title: Loop Quantum Gravity: A interdisciplinary topic Location: Central Department of Physics, T.U., Nepal Show/Hide Abstract Abstract
Loop quantum gravity (LQG) is a theoretical framework that attempts to reconcile the principles of general relativity, the theory of gravitation, with quantum mechanics, the theory that describes the behavior of matter and energy at the smallest scales. In LQG, space-time is quantized into discrete units, and the geometry of space-time is described in terms of spin networks, which are graphs representing the interconnections between space-time points. There are various aspects or fundamentals to this topic. This report aims to provide a wide view on various aspects of their fundamentality and provide with a wider perspective to its challenges and sucess majors to upbring as a major contendor for the holy grail of physics "The Theory of Everything ". This report is included with details on tge basic principles of Loop Quantam Gravity. It includes : Canonical quantization,Discrete space-time,Holonomies and connections,Spin networks,Background independence,Diffeomorphism invariance,Emergence of space-time. Also providing a wider view to its challenges and promising future directions, This report impacts on other various big topics in physics such as Cosmology, Particle Physics, Philosophical bibilographies as well as Quantam Mechanics.
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Abstract Number: ANPA2023-N0008 Presenting Author: Purna Jyoti Shakya Presenter's Affiliation: Patan Multiple Campus, IoST, Tribhuvan University, Nepal Location: Central Department of Physics, T.U., Nepal Show/Hide Abstract Ultra low frequency (ULF) waves are an important consideration to identify the dominant process that transfer energy from solar wind to Earth’s inner magnetosphere as they propagate electromagnetic energy over vast distance with little dissipation. The waves observed on the Earth depends on conditions in the solar wind and in the magnetosphere. In this work, we investigate the Pc pulsation observed in the 12-15 UT time interval during geomagnetic storm of September 8th 2017 using data from the SuperMAG and the OMNIWeb services. We used Pc pulsation data observed at T48 station (geographic latitude: 54.8o, geographic longitude: 293.19o), Schefferville, Canada. Cross-correlation analysis shows that Pc2, Pc3, Pc4 and Pc5 ULF wave are positively correlated with interplanetary magnetic field, AE index and Polar cap index. Similarly, cross-correlation of Pc pulsations with solar wind density (Nsw), solar wind pressure (Psw) and solar wind velocity (Vsw), shows that they are positively correlated with no time lag, indicating sudden increase in solar wind density and velocity due to IP shocks result in a gradual increase in dynamic solar wind pressure and sudden compression from the Earth’s dayside magnetosphere. As a result, acoustic magnetic wave are ejected into the magnetosphere.
Key words: Ultra Low Frequency (ULF), Pc Pulsation, Geomagnetic Storm, Magnetosphere.
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Abstract Number: ANPA2023-N00014 Presenting Author: Suman Dhakal (Invited) Presenter's Affiliation: George Mason University, VA Title: What Are the Causes of Super Flare Productivity of Solar Active Regions Location: Virtual Presentation Show/Hide Abstract Solar active regions (ARs) are the main sources of solar flares. Flare productivity varies among ARs, but the physical processes determining the flare activity of an AR are not clear. In this study we compared the evolution of super flare productive and low flare productive ARs. We selected 20 ARs of contrasting flare activities and sunspot sizes. Though the magnetic flux emergence is important, our study shows that it alone is not sufficient to increase the flare productivity of an AR. The new emergence can lead to either the interaction of like or opposite magnetic fluxes of non-conjugate pairs (magnetic poles not emerging together as a conjugate pair, as in a bipolar configuration). In the former case, the overall magnetic configuration remains simple and the flare productivity of AR does not change with emergence. In the latter case, the convergence of opposite magnetic fluxes of non-conjugate pairs results in a complex magnetic configuration with long polarity inversion line (PIL). Our case study of AR 11429 and other ARs shows that the persistent shearing motion and flux cancellation along such PIL results in repetitive homologous solar eruption. Further, our study suggests that length of PIL is the best magnetic-field parameter to reflect the flare productivity.
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Abstract Number: ANPA2023-N00012 Presenting Author: Aayush Gautam Presenter's Affiliation: Birendra Multiple Campus, Tribhuvan University, Nepal Title: Constraining X-ray variability of blazars BL Lacertae, Mrk 421, and Mrk 501 using Swift-XRT Location: Virtual Presentation Show/Hide Abstract Blazars, a subclass of active galactic nuclei, represent one of the most luminous sources in the Universe. The sources featuring relativistic jets aligned closely to the line of sight are believed to be powered by supermassive black holes at the center. Blazars exhibit multi-wave band flux variability in diverse timescales, that is, from a few minutes to decades. In this work, we present a study of the long-term variability properties of three blazars BL Lacertae, Mrk 421, and Mrk 501 using 17-year (2005 - 2022) long archival observations from the XRT telescope of the Neil Gehrels Swift Observatory (Swift-XRT). We applied various methods of timing analysis including fractional variability, count-rate distributions, and power spectral density (PSD) to investigate the temporal variability in the 0.3-10 KeV energy range. In addition, we studied the evolution of the hardness ratio in the same period. The results indicate that the X-ray light curves are highly variable with a fractional variability of 83 ± 1%. The PSD is consistent with a power law. and the probability density function (PDF) of the count rates is best represented by heavy-tailed log-normal. Models involving shocks in the jets and magnetic reconnection events in a turbulent jet can be used to explain the observed results.
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Abstract Number: ANPA2023-N00015 Presenting Author: Timothy O'leary Presenter's Affiliation: Worcester State University Title: Neighborhood-Level Air Pollution Monitoring and Analysis in Massachusetts Location: Virtual Presentation Show/Hide Abstract Air pollution is a significant environmental issue with far-reaching consequences for both human health and the planet. It arises from the emission of harmful pollutants, such as particulate matter, ozone, and nitrogen dioxide, into the atmosphere. These pollutants originate from various sources, including vehicles, industrial facilities, and power plants. The impacts of air pollution are wide-ranging, encompassing respiratory infections, cardiovascular disease, cancer, harm to ecosystems, and contributions to climate change. The study of air pollution is a multidisciplinary field that draws upon knowledge from physics, chemistry, biology, and engineering.
Understanding the causes and effects of air pollution is crucial for developing effective strategies to mitigate its harmful effects. Physics, in particular, plays a vital role in this field by providing the tools and techniques required to measure and comprehend the behavior of pollutants. By examining air pollution, we gain insights into the factors driving this problem and can devise measures to reduce pollution levels. Moreover, this knowledge empowers individuals and societies to make informed decisions about minimizing exposure to pollutants and formulating policies and regulations that safeguard both human well-being and the environment.
In our study conducted in the central Massachusetts region, we investigated the status of air pollution using a combination of Environmental Protection Agency (EPA) monitoring sites and hand-held sensors. While the EPA sites offer long-term monitoring data, hand-held devices' flexible and affordable nature allowed us to explore air quality at the local neighborhood and street levels. By utilizing these tools, we assessed the spatial and temporal variations in air pollution within the city, aiding in the identification of localized hotspots. Such information is valuable for targeting specific areas requiring interventions and further understanding the dynamics of pollution distribution.
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Abstract Number: ANPA2023-N00013 Presenting Author: Rudra Aryal Presenter's Affiliation: Franklin Pierce University Title: Long-term Observation of Air Pollution Trends over Massachusetts, USA Location: Virtual Presentation Show/Hide Abstract Harmful chemicals in our atmosphere negatively impact the environment and human health. This research study analyzed air pollution data from the past ten years (2012-2022) in Massachusetts, explicitly examining levels of toxins like lead, carbon monoxide, nitrogen dioxide, sulfur dioxide, ozone, and particulate matter PM2.5 and PM10 in different counties. Data on the levels of pollutants were measured and reported by the United States Protection Agency (EPA) and analyzed in a study that examined air quality variations on a monthly, seasonal, and yearly basis. The study found that areas with higher population densities had more significant air pollution, while areas with lower populations had less. Suffolk, which encompasses Boston, had the highest levels of air pollution, whereas Nantucket had the lowest.
The study aims to compare the ground-based Nitrogen dioxide (NO2) measurements taken by the U.S. Environmental Protection Agency (EPA) with those from the European Space Agency (ESA) TROPOMI (TROPOspheric Monitoring Instrument) satellite. It examines NO2 as it is one of the major pollutants involving respiratory diseases like asthma, which can result in symptoms like coughing and wheezing, causing lung harm. Moreover, there is a large amount of data on this component. Furthermore, nitrogen oxides interact with other atmospheric chemicals, resulting in acid rain, particulate matter, and ozone, significant contributors to declining air quality in urban and industrial areas. We also utilized the TROPOMI satellite and the U.S. EPA NO2 products to create a mapping of NO2 levels both from space and on the ground. The impact of COVID-19 on the levels of tropospheric NO2 in Massachusetts was analyzed using NO2-based measurements. This helped determine how long COVID-19 had an effect and how the decrease in traffic affected air pollution. Additionally, the study estimated the impact on other air pollutants.
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Abstract Number: ANPA2023-N00011 Presenting Author: Jose L. Parra Presenter's Affiliation: Florida International University Title: The Gravitational Energy according to the General Theory of Relativity Location: Florida International University, FL, USA Show/Hide Abstract The actual opinion is that we are living in a universe almost full of darkness. To bring some light into play, it will be introduced here an exact solution of Einstein’s equations of General Relativity with consequences in agreement with the known galactic data. Also, the model allows us to forecast that a clear gravitational perturbation was going to come from the center of the Milky Way at a specific date and time. That event was observed as expected with two modified Cavendish’s balances within 2.6 kilometers of separation.
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