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Full-Text Articles in Physical Sciences and Mathematics
Black Hole Hyperaccretion Inflow-Outflow Model. I. Long And Ultra-Long Gamma-Ray Bursts, Tong Liu, Cui-Ying Song, Bing Zhang, Wei-Min Gu, Alexander Heger
Black Hole Hyperaccretion Inflow-Outflow Model. I. Long And Ultra-Long Gamma-Ray Bursts, Tong Liu, Cui-Ying Song, Bing Zhang, Wei-Min Gu, Alexander Heger
Physics & Astronomy Faculty Research
Long-duration gamma-ray bursts (LGRBs) and ultra-LGRBs (ULGRBs) originate from collapsars, in the center of which a newborn rotating stellar-mass black hole (BH) surrounded by a massive accretion disk may form. In the scenario of the BH hyperaccretion inflow-outflow model and Blandford-Znajek (BZ) mechanism to trigger gamma-ray bursts (GRBs), the real accretion rate to power a BZ jet is far lower than the mass supply rate from the progenitor star. The characteristics of the progenitor stars can be constrained by GRB luminosity observations, and the results exceed usual expectations. LGRBs lasting from several seconds to tens of seconds in the rest …
The Alma Early Science View Of Fuor/Exor Objects - V. Continuum Disc Masses And Sizes, Lucas Cieza, Dary Ruiz-Rodriguez, Sebastian Perez, Simon Casassus, Jonathan P. Williams, Alice Zurlo, David A. Principe, Antonio Hales, Jose L. Prieto, John J. Tobin, Zhaohuan Zhu, Sebastian Marino
The Alma Early Science View Of Fuor/Exor Objects - V. Continuum Disc Masses And Sizes, Lucas Cieza, Dary Ruiz-Rodriguez, Sebastian Perez, Simon Casassus, Jonathan P. Williams, Alice Zurlo, David A. Principe, Antonio Hales, Jose L. Prieto, John J. Tobin, Zhaohuan Zhu, Sebastian Marino
Physics & Astronomy Faculty Research
Low-mass stars build a significant fraction of their total mass during short outbursts of enhanced accretion known as FUor and EXor outbursts. FUor objects are characterized by a sudden brightening of ∼5 mag at visible wavelengths within 1 yr and remain bright for decades. EXor objects have lower amplitude outbursts on shorter time-scales. Here we discuss a 1.3 mm Atacama Large Millimeter/submillimeter Array (ALMA) mini-survey of eight outbursting sources (three FUors, four EXors, and the borderline object V1647 Ori) in the Orion Molecular Cloud. While previous papers in this series discuss the remarkable molecular outflows observed in the three FUor …
Hyperaccreting Black Hole As Gamma-Ray Burst Central Engine. Ii. Temporal Evolution Of The Central Engine Parameters During The Prompt And Afterglow Phases, Wei-Hua Lei, Bing Zhang, Xue-Feng Wu, En-Wei Liang
Hyperaccreting Black Hole As Gamma-Ray Burst Central Engine. Ii. Temporal Evolution Of The Central Engine Parameters During The Prompt And Afterglow Phases, Wei-Hua Lei, Bing Zhang, Xue-Feng Wu, En-Wei Liang
Physics & Astronomy Faculty Research
A hyperaccreting stellar-mass black hole (BH) has been proposed as the candidate central engine of gamma-ray bursts (GRBs). The rich observations of GRBs by Fermi and Swiftmake it possible to constrain the central engine model by comparing the model predictions against data. This paper is dedicated to studying the temporal evolution of the central engine parameters for both the prompt emission and afterglow phases. We consider two jet-launching mechanisms, i.e., annihilations and the Blandford–Znajek (BZ) process, and obtain analytical solutions to these two models. We then investigate the BH central engine parameters, such as the jet power, the dimensionless entropy …
How Do Stars Gain Their Mass? A Jcmt/Scuba-2 Transient Survey Of Protostars In Nearby Star-Forming Regions, Gregory J. Herczeg, Doug Johnstone, Steve Mairs, Jennifer Hatchell, Jeong-Eun Lee, Geoffrey C. Bower, Huei-Ru Vivien Chen, Yuri Aikawa, Hyunju Yoo, Sung-Ju Kang, Miju Kang, Wen-Ping Chen, Jonathan P. Williams, Jaehan Bae, Michael M. Dunham, Eduard I. Vorobyov, Zhaohuan Zhu, Ramprasad Rao, Helen Kirk, Satoko Takahashi, Oscar Morata, Kevin Lacaille, James Lane, Andy Pon, Aleks Scholz, Manash R. Samal, Graham S. Bell, Sarah Graves, E'Lisa M. Lee, Harriet Parsons, Yuxin He
How Do Stars Gain Their Mass? A Jcmt/Scuba-2 Transient Survey Of Protostars In Nearby Star-Forming Regions, Gregory J. Herczeg, Doug Johnstone, Steve Mairs, Jennifer Hatchell, Jeong-Eun Lee, Geoffrey C. Bower, Huei-Ru Vivien Chen, Yuri Aikawa, Hyunju Yoo, Sung-Ju Kang, Miju Kang, Wen-Ping Chen, Jonathan P. Williams, Jaehan Bae, Michael M. Dunham, Eduard I. Vorobyov, Zhaohuan Zhu, Ramprasad Rao, Helen Kirk, Satoko Takahashi, Oscar Morata, Kevin Lacaille, James Lane, Andy Pon, Aleks Scholz, Manash R. Samal, Graham S. Bell, Sarah Graves, E'Lisa M. Lee, Harriet Parsons, Yuxin He
Physics & Astronomy Faculty Research
Most protostars have luminosities that are fainter than expected from steady accretion over the protostellar lifetime. The solution to this problem may lie in episodic mass accretion—prolonged periods of very low accretion punctuated by short bursts of rapid accretion. However, the timescale and amplitude for variability at the protostellar phase is almost entirely unconstrained…See full text for full abstract.
Challenging The Forward Shock Model With The 80 Ms Follow Up Of The X-Ray Afterglow Of Gamma-Ray Burst 130427a, Massimiliano De Pasquale, Matthew Page, David Alexander Kann, Samantha R. Oates, Steve Schulze, Bing Zhang, Zach Cano, Bruce Gendre, Daniele Malesani, Andrea Rossi, Neil Gehrels, Eleonora Troja, Luigi Piro, Michel Boer, Giulia Stratta
Challenging The Forward Shock Model With The 80 Ms Follow Up Of The X-Ray Afterglow Of Gamma-Ray Burst 130427a, Massimiliano De Pasquale, Matthew Page, David Alexander Kann, Samantha R. Oates, Steve Schulze, Bing Zhang, Zach Cano, Bruce Gendre, Daniele Malesani, Andrea Rossi, Neil Gehrels, Eleonora Troja, Luigi Piro, Michel Boer, Giulia Stratta
Physics & Astronomy Faculty Research
GRB 130427A was the most luminous gamma-ray burst detected in the last 30 years. With an isotropic energy output of 8.5 × 1053 erg and redshift of 0.34, it combined very high energetics with a relative proximity to Earth in an unprecedented way. Sensitive X-ray observatories such as XMM-Newton and Chandra have detected the afterglow of this event for a record-breaking baseline longer than 80 million seconds. The light curve displays a simple power-law over more than three decades in time. In this presentation, we explore the consequences of this result for a few models put forward so far to …