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6,578 full-text articles. Page 7 of 203.

Propagation Of A Short Grb Jet In The Ejecta: Jet Launching Delay Time, Jet Structure, And Gw170817/Grb 170817a, Jin-Jun Geng, Bing Zhang, Anders Kölligan, Rolf Kuiper, Yong-Feng Huang 2019 Nanjing University

Propagation Of A Short Grb Jet In The Ejecta: Jet Launching Delay Time, Jet Structure, And Gw170817/Grb 170817a, Jin-Jun Geng, Bing Zhang, Anders Kölligan, Rolf Kuiper, Yong-Feng Huang

Physics & Astronomy Faculty Publications

We perform a series of relativistic magnetohydrodynamic simulations to investigate how a hot magnetic jet propagates within the dynamical ejecta of a binary neutron star merger, focusing on how the jet structure depends on the delay time of jet launching with respect to the merger time, Δt jet. We find that regardless of the jet-launching delay time, a structured jet with an angle-dependent luminosity and Lorentz factor is always formed after the jet breaks out of the ejecta. On the other hand, the jet-launching delay time has an impact on the jet structure. If the jet-launching delay time is relatively ...


Figure 8: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 8: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Figure 3: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 3: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Figure 5: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 5: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Figure 9: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 9: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Figure 2: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 2: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Figure 10: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 10: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Figure 4: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 4: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Figure 1: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 1: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Figure 7: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 7: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Figure 6: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri 2019 Embry-Riddle Aeronautical University

Figure 6: Simulation Results For Flux Tube Entropy And Specific Entropy In Saturn's Magnetosphere, Xuanye Ma, Peter A. Delamere, Michelle F. Thomsen, Antonius Otto, Bishwa Neupane, Brandon Burkholder, Katariina Nykyri

Katariina Nykyri

No abstract provided.


Microcontroller Differential Gps To Subtract Signal Delay Due To Ambient Free Electrons In The Ionosphere, Diana Jane Swanson 2019 California Polytechnic State University, San Luis Obispo

Microcontroller Differential Gps To Subtract Signal Delay Due To Ambient Free Electrons In The Ionosphere, Diana Jane Swanson

Physics

The goal of this project is to create a Global Positioning System (GPS) receiver that is more precise than one GPS receiver on its own. The technique is to take the difference between a GPS receiver’s measured position and its actual position, then use radio frequency (RF) communication to send that differential value to another microcontroller GPS receiver. This differential value will be added to the measured second location to get a more accurate position for the second GPS receiver, thus creating a differential GPS.


Multi-Wavelength Investigation Of Energy Release And Chromospheric Evaporation In Solar Flares, Viacheslav M. Sadykov 2019 New Jersey Institute of Technology

Multi-Wavelength Investigation Of Energy Release And Chromospheric Evaporation In Solar Flares, Viacheslav M. Sadykov

Dissertations

For a comprehensive understanding of the energy release and chromospheric evaporation processes in solar flares it is necessary to perform a combined multi-wavelength analysis using observations from space-based and ground-based observatories, and compare the results with predictions of the radiative hydrodynamic (RHD) flare models. Initially, the case study of spatially-resolved chromospheric evaporation properties for an M\,1.0-class solar flare (SOL2014-06-12T21:12) using data form IRIS (Interface Region Imaging Spectrograph), HMI/SDO (Helioseismic and Magnetic Imager onboard Solar Dynamics Observatory), and VIS/GST (Visible Imaging Spectrometer at Goode Solar Telescope), demonstrate a complicated nature of evaporation and its connection to ...


A Tight Relation Between Spiral Arm Pitch Angle And Protplanetary Disk Mass, Si-Yue Yu, Luis C. Ho, Zhaohuan Zhu 2019 Peking University

A Tight Relation Between Spiral Arm Pitch Angle And Protplanetary Disk Mass, Si-Yue Yu, Luis C. Ho, Zhaohuan Zhu

Physics & Astronomy Faculty Publications

We use two-dimensional Fourier transformation to measure the pitch angle () of the dominant spiral Fourier mode of well-defined spiral arms in 13 protoplanetary disks, making use of near-infrared scattered-light images of AB Aur, SAO 206462, MWC 758, V1247 Ori, HD 142527, DZ Cha, LkHα 330, and HD 100453, and ALMA millimeter continuum images of Elias 2-27, IM Lup, AS 205, and HT Lup. We find that the measured pitch angle correlates strongly with disk mass (M D ), such that more massive protoplanetary disks have smaller pitch angles, following . Interestingly, four disks with a known companion (HD 142527, HD 100453, AS ...


A Hard Look At Ngc 5347: Revealing A Nearby Compton-Thick Agn, E. S. Kammoun, J. M. Miller, A. Zoghbi, K. Oh, M. Koss, R. F. Muchotzky, L. W. Brenneman, W. N. Brandt, Daniel Proga, A. M. Lohfink, J. S. Kaastra, D. Barret, E. Behar, D. Stern 2019 University of Michigan

A Hard Look At Ngc 5347: Revealing A Nearby Compton-Thick Agn, E. S. Kammoun, J. M. Miller, A. Zoghbi, K. Oh, M. Koss, R. F. Muchotzky, L. W. Brenneman, W. N. Brandt, Daniel Proga, A. M. Lohfink, J. S. Kaastra, D. Barret, E. Behar, D. Stern

Physics & Astronomy Faculty Publications

Current measurements show that the observed fraction of Compton-thick (CT) active galactic nuclei (AGN) is smaller than the expected values needed to explain the cosmic X-ray background. Prior fits to the X-ray spectrum of the nearby Seyfert-2 galaxy NGC 5347 (z = 0.00792, D = 35.5 Mpc ) have alternately suggested a CT and Compton-thin source. Combining archival data from Suzaku, Chandra, and—most importantly—new data from NuSTAR, ... See full text for complete abstract


Long-Term Dust Formation By Core Collapse Supernovae, Kelsie Marie Krafton 2019 Louisiana State University and Agricultural and Mechanical College

Long-Term Dust Formation By Core Collapse Supernovae, Kelsie Marie Krafton

LSU Doctoral Dissertations

Studying long-term dust formation by CCSNe is an important step toward understanding the large dust masses found in early galaxies. The amazing new discovery of approximately a solar mass of cold dust in the ejecta of SN 1987A has caused a complete re-evaluation of dust formation in core collapse supernovae (CCSNe). CCSNe form only a small amount of dust after three years, but SN 1987A has a dust mass that is several orders of magnitude larger after 25 years. A recent study of SN 2010jl by Gall et al. (2014) made the fascinating suggestion that dust is continuously forming in ...


One Solution To The Mass Budget Problem For Planet Formation: Optically Thick Disks With Dust Scattering, Zhaohuan Zhu, Shangjia Zhang, Yan-Fei Jiang, Akimasa Kataoka, Tilman Birnstiel, Cornelis P. Dullemond, Sean M. Andrews, Jane Huang, Laura M. Perez, John M. Carpenter, Xue-Ning Bai, David J. Wilner, Luca Ricci 2019 University of Nevada, Las Vegas

One Solution To The Mass Budget Problem For Planet Formation: Optically Thick Disks With Dust Scattering, Zhaohuan Zhu, Shangjia Zhang, Yan-Fei Jiang, Akimasa Kataoka, Tilman Birnstiel, Cornelis P. Dullemond, Sean M. Andrews, Jane Huang, Laura M. Perez, John M. Carpenter, Xue-Ning Bai, David J. Wilner, Luca Ricci

Physics & Astronomy Faculty Publications

Atacama Large Millimeter Array (ALMA) surveys have suggested that the dust in Class II disks may not be enough to explain the averaged solid mass in exoplanets, under the assumption that the mm disk continuum emission is optically thin. This optically thin assumption seems to be supported by recent Disk Substructures at High Angular Resolution Project (DSHARP) observations where the measured optical depths are mostly less than one. However, we point out that dust scattering can considerably reduce the emission from an optically thick region. If that scattering is ignored, an optically thick disk with scattering can be misidentified as ...


Modeling The Light Curves Of The Luminous Type Ic Supernova 2007d, Shan-Qin Wang, Zach Cano, Long Li, Liang-Duan Liu, Ling-Jun Wang, WeiKang Zheng, Zi-Gao Dai, En-Wei Liang, Alexei V. Filippenko 2019 Nanjing University

Modeling The Light Curves Of The Luminous Type Ic Supernova 2007d, Shan-Qin Wang, Zach Cano, Long Li, Liang-Duan Liu, Ling-Jun Wang, Weikang Zheng, Zi-Gao Dai, En-Wei Liang, Alexei V. Filippenko

Physics & Astronomy Faculty Publications

SN 2007D is a nearby (redshift z = 0.023146), luminous Type Ic supernova (SN) having a narrow light curve (LC) and high peak luminosity. Previous research based on the assumption that it was powered by the 56Ni cascade decay suggested that the inferred 56Ni mass and the ejecta mass are ~1.5 M ⊙ and ~3.5 M ⊙, respectively. In this paper, we employ some multiband LC models to model the R-band LC and the color (V − R) evolution of SN 2007D to investigate the possible energy sources powering them. We find that the pure 56Ni model is disfavored; the multiband ...


Real-Time Rfi Mitigation In Radio Astronomy, Emily Ramey, Nick Joslyn, Richard Prestage, Michael Lam, Luke Hawkins, Tim Blattner, Mark Whitehead 2019 Washington University in St. Louis

Real-Time Rfi Mitigation In Radio Astronomy, Emily Ramey, Nick Joslyn, Richard Prestage, Michael Lam, Luke Hawkins, Tim Blattner, Mark Whitehead

Senior Honors Papers / Undergraduate Theses

As the use of wireless technology has increased around the world, Radio Frequency Interference (RFI) has become more and more of a problem for radio astronomers. Preventative measures exist to limit the presence of RFI, and programs exist to remove it from saved data, but the use of algorithms to detect and remove RFI as an observation is occurring is much less common. Such a method would be incredibly useful for observations in which the data must undergo several rounds of processing before being saved, as in pulsar timing studies. Strategies for real-time mitigation have been discussed and tested with ...


Arecibo Message, Joshua P. Tan 2019 CUNY La Guardia Community College

Arecibo Message, Joshua P. Tan

Open Educational Resources

This two week assignment asks students to interpret and analyze the 1974 Arecibo Message sent by Drake and Sagan. Week 1 introduces the concepts behind the construction of the message and engages with a critical analysis of the architecture and the contents of the message. Week 2 asks students to develop software in a Jupyter Notebook (available for free from the Anaconda Python Distribution) to interpret messages that were similar to those produced by Drake and Sagan.


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