Pub Date : 2023-11-01DOI: 10.3847/2041-8213/ad0159
Massimo Stiavelli, Takahiro Morishita, Marco Chiaberge, Claudio Grillo, Nicha Leethochawalit, Piero Rosati, Stefan Schuldt, Michele Trenti, Tommaso Treu
Abstract We analyze new JWST NIRCam and NIRSpec data on the redshift 9.11 galaxy MACS1149-JD1 (hereafter JD1). Our NIRCam imaging data reveal that JD1 comprises three spatially distinct components. Our spectroscopic data indicate that JD1 appears dust free but is already enriched, 12+log(O/H)=7.90−0.05+0.04 . We also find that the carbon and neon abundances in JD1 are below the solar abundance ratio. Particularly the carbon under-abundance is suggestive of recent star formation where Type II supernovae have already enriched the interstellar medium (ISM) in oxygen but intermediate mass stars have not yet enriched the ISM in carbon. A recent burst of star formation is also revealed by the star formation history derived from NIRCam photometry. Our data do not reveal the presence of a significant amount of old populations, resulting in a factor of ∼7× smaller stellar mass than previous estimates. Thus, our data support the view that JD1 is a young galaxy.
{"title":"The Puzzling Properties of the MACS1149-JD1 Galaxy at z = 9.11","authors":"Massimo Stiavelli, Takahiro Morishita, Marco Chiaberge, Claudio Grillo, Nicha Leethochawalit, Piero Rosati, Stefan Schuldt, Michele Trenti, Tommaso Treu","doi":"10.3847/2041-8213/ad0159","DOIUrl":"https://doi.org/10.3847/2041-8213/ad0159","url":null,"abstract":"Abstract We analyze new JWST NIRCam and NIRSpec data on the redshift 9.11 galaxy MACS1149-JD1 (hereafter JD1). Our NIRCam imaging data reveal that JD1 comprises three spatially distinct components. Our spectroscopic data indicate that JD1 appears dust free but is already enriched, <?CDATA $12+mathrm{log}({rm{O}}/{rm{H}})={7.90}_{-0.05}^{+0.04}$?> <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\"> <mml:mn>12</mml:mn> <mml:mo>+</mml:mo> <mml:mi>log</mml:mi> <mml:mo stretchy=\"false\">(</mml:mo> <mml:mi mathvariant=\"normal\">O</mml:mi> <mml:mrow> <mml:mo stretchy=\"true\">/</mml:mo> </mml:mrow> <mml:mi mathvariant=\"normal\">H</mml:mi> <mml:mo stretchy=\"false\">)</mml:mo> <mml:mo>=</mml:mo> <mml:msubsup> <mml:mrow> <mml:mn>7.90</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>0.05</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>0.04</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> . We also find that the carbon and neon abundances in JD1 are below the solar abundance ratio. Particularly the carbon under-abundance is suggestive of recent star formation where Type II supernovae have already enriched the interstellar medium (ISM) in oxygen but intermediate mass stars have not yet enriched the ISM in carbon. A recent burst of star formation is also revealed by the star formation history derived from NIRCam photometry. Our data do not reveal the presence of a significant amount of old populations, resulting in a factor of ∼7× smaller stellar mass than previous estimates. Thus, our data support the view that JD1 is a young galaxy.","PeriodicalId":55567,"journal":{"name":"Astrophysical Journal Letters","volume":"14 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135460565","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-01DOI: 10.3847/2041-8213/ad0387
Thomas S.-Y. 劭愉 Lai 賴, Lee Armus, Marina Bianchin, Tanio Díaz-Santos, Sean T. Linden, George C. Privon, Hanae Inami, Vivian U, Thomas Bohn, Aaron S. Evans, Kirsten L. Larson, Brandon S. Hensley, J.-D. T. Smith, Matthew A. Malkan, Yiqing Song, Sabrina Stierwalt, Paul P. van der Werf, Jed McKinney, Susanne Aalto, Victorine A. Buiten, Jeff Rich, Vassilis Charmandaris, Philip Appleton, Loreto Barcos-Muñoz, Torsten Böker, Luke Finnerty, Justin A. Kader, David R. Law, Anne M. Medling, Michael J. I. Brown, Christopher C. Hayward, Justin Howell, Kazushi Iwasawa, Francisca Kemper, Jason Marshall, Joseph M. Mazzarella, Francisco Müller-Sánchez, Eric J. Murphy, David Sanders, Jason Surace
Abstract We present James Webb Space Telescope (JWST) Near Infrared Spectrograph (NIRSpec) integral field spectroscopy of the nearby luminous infrared galaxy NGC 7469. We take advantage of the high spatial/spectral resolution and wavelength coverage of JWST/NIRSpec to study the 3.3 μ m neutral polycyclic aromatic hydrocarbon (PAH) grain emission on ∼200 pc scales. A clear change in the average grain properties between the star-forming ring and the central AGN is found. Regions in the vicinity of the AGN, with [Ne iii ]/[Ne ii ] > 0.25, tend to have larger grain sizes and lower aliphatic-to-aromatic (3.4/3.3) ratios, indicating that smaller grains are preferentially removed by photodestruction in the vicinity of the AGN. PAH emission at the nucleus is weak and shows a low 11.3/3.3 PAH ratio. We find an overall suppression of the total PAH emission relative to the ionized gas in the central 1 kpc region of the AGN in NGC 7469 compared to what has been observed with Spitzer on 3 kpc scales. However, the fractional 3.3 μ m–to–total PAH power is enhanced in the starburst ring, possibly due to a variety of physical effects on subkiloparsec scales, including recurrent fluorescence of small grains or multiple photon absorption by large grains. Finally, the IFU data show that while the 3.3 μ m PAH-derived star formation rate (SFR) in the ring is 27% higher than that inferred from the [Ne ii ] and [Ne iii ] emission lines, the integrated SFR derived from the 3.3 μ m feature would be underestimated by a factor of 2 due to the deficit of PAHs around the AGN, as might occur if a composite system like NGC 7469 were to be observed at high redshift.
{"title":"GOALS-JWST: Small Neutral Grains and Enhanced 3.3 μm PAH Emission in the Seyfert Galaxy NGC 7469","authors":"Thomas S.-Y. 劭愉 Lai 賴, Lee Armus, Marina Bianchin, Tanio Díaz-Santos, Sean T. Linden, George C. Privon, Hanae Inami, Vivian U, Thomas Bohn, Aaron S. Evans, Kirsten L. Larson, Brandon S. Hensley, J.-D. T. Smith, Matthew A. Malkan, Yiqing Song, Sabrina Stierwalt, Paul P. van der Werf, Jed McKinney, Susanne Aalto, Victorine A. Buiten, Jeff Rich, Vassilis Charmandaris, Philip Appleton, Loreto Barcos-Muñoz, Torsten Böker, Luke Finnerty, Justin A. Kader, David R. Law, Anne M. Medling, Michael J. I. Brown, Christopher C. Hayward, Justin Howell, Kazushi Iwasawa, Francisca Kemper, Jason Marshall, Joseph M. Mazzarella, Francisco Müller-Sánchez, Eric J. Murphy, David Sanders, Jason Surace","doi":"10.3847/2041-8213/ad0387","DOIUrl":"https://doi.org/10.3847/2041-8213/ad0387","url":null,"abstract":"Abstract We present James Webb Space Telescope (JWST) Near Infrared Spectrograph (NIRSpec) integral field spectroscopy of the nearby luminous infrared galaxy NGC 7469. We take advantage of the high spatial/spectral resolution and wavelength coverage of JWST/NIRSpec to study the 3.3 μ m neutral polycyclic aromatic hydrocarbon (PAH) grain emission on ∼200 pc scales. A clear change in the average grain properties between the star-forming ring and the central AGN is found. Regions in the vicinity of the AGN, with [Ne iii ]/[Ne ii ] > 0.25, tend to have larger grain sizes and lower aliphatic-to-aromatic (3.4/3.3) ratios, indicating that smaller grains are preferentially removed by photodestruction in the vicinity of the AGN. PAH emission at the nucleus is weak and shows a low 11.3/3.3 PAH ratio. We find an overall suppression of the total PAH emission relative to the ionized gas in the central 1 kpc region of the AGN in NGC 7469 compared to what has been observed with Spitzer on 3 kpc scales. However, the fractional 3.3 μ m–to–total PAH power is enhanced in the starburst ring, possibly due to a variety of physical effects on subkiloparsec scales, including recurrent fluorescence of small grains or multiple photon absorption by large grains. Finally, the IFU data show that while the 3.3 μ m PAH-derived star formation rate (SFR) in the ring is 27% higher than that inferred from the [Ne ii ] and [Ne iii ] emission lines, the integrated SFR derived from the 3.3 μ m feature would be underestimated by a factor of 2 due to the deficit of PAHs around the AGN, as might occur if a composite system like NGC 7469 were to be observed at high redshift.","PeriodicalId":55567,"journal":{"name":"Astrophysical Journal Letters","volume":"38 11","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135510172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-01DOI: 10.3847/2041-8213/ad0788
Anshu Gupta, Ravi Jaiswar, Vicente Rodriguez-Gomez, Ben Forrest, Kim-Vy Tran, Themiya Nanayakkara, Anishya Harshan, Elisabete da Cunha, Glenn G. Kacprzak, Michaela Hirschmann
Abstract Extreme emission line galaxies (EELGs), where nebular emissions contribute 30%–40% of the flux in certain photometric bands, are ubiquitous in the early Universe ( z > 6). We utilize deep NIRCam imaging from the JWST Advanced Deep Extragalactic Survey ( JADES ) to investigate the properties of companion galaxies (projected distance <40 kpc, ∣ dv ∣ < 10,000 km s −1 ) around EELGs at z ∼ 3. Tests with TNG100 simulation reveal that nearly all galaxies at z = 3 will merge with at least one companion galaxy selected using similar parameters by z = 0. The median mass ratio of the most massive companion and the total mass ratio of all companions around EELGs is more than 10 times higher the control sample. Even after comparing with a stellar mass and stellar mass plus specific star formation rate (SFR)-matched control sample, EELGs have 3 to 5 times higher mass ratios than the brightest companion and total mass ratio of all companions. Our measurements suggest that EELGs are more likely to be experiencing strong interactions or undergoing major mergers irrespective of their stellar mass or specific SFRs. We suspect that gas cooling induced by strong interactions and/or major mergers could be triggering the extreme emission lines, and the increased merger rate might be responsible for the overabundance of EELGs at z > 6.
{"title":"MOSEL Survey: JWST Reveals Major Mergers/strong Interactions Drive the Extreme Emission Lines in the Early Universe","authors":"Anshu Gupta, Ravi Jaiswar, Vicente Rodriguez-Gomez, Ben Forrest, Kim-Vy Tran, Themiya Nanayakkara, Anishya Harshan, Elisabete da Cunha, Glenn G. Kacprzak, Michaela Hirschmann","doi":"10.3847/2041-8213/ad0788","DOIUrl":"https://doi.org/10.3847/2041-8213/ad0788","url":null,"abstract":"Abstract Extreme emission line galaxies (EELGs), where nebular emissions contribute 30%–40% of the flux in certain photometric bands, are ubiquitous in the early Universe ( z > 6). We utilize deep NIRCam imaging from the JWST Advanced Deep Extragalactic Survey ( JADES ) to investigate the properties of companion galaxies (projected distance <40 kpc, ∣ dv ∣ < 10,000 km s −1 ) around EELGs at z ∼ 3. Tests with TNG100 simulation reveal that nearly all galaxies at z = 3 will merge with at least one companion galaxy selected using similar parameters by z = 0. The median mass ratio of the most massive companion and the total mass ratio of all companions around EELGs is more than 10 times higher the control sample. Even after comparing with a stellar mass and stellar mass plus specific star formation rate (SFR)-matched control sample, EELGs have 3 to 5 times higher mass ratios than the brightest companion and total mass ratio of all companions. Our measurements suggest that EELGs are more likely to be experiencing strong interactions or undergoing major mergers irrespective of their stellar mass or specific SFRs. We suspect that gas cooling induced by strong interactions and/or major mergers could be triggering the extreme emission lines, and the increased merger rate might be responsible for the overabundance of EELGs at z > 6.","PeriodicalId":55567,"journal":{"name":"Astrophysical Journal Letters","volume":"20 10","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135715176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-01DOI: 10.3847/2041-8213/acff6f
Freek Roelofs, Michael D. Johnson, Andrew Chael, Michael Janssen, Maciek Wielgus, Avery E. Broderick, Kazunori Akiyama, Antxon Alberdi, Walter Alef, Juan Carlos Algaba, Richard Anantua, Keiichi Asada, Rebecca Azulay, Uwe Bach, Anne-Kathrin Baczko, David Ball, Mislav Baloković, John Barrett, Michi Bauböck, Bradford A. Benson, Dan Bintley, Lindy Blackburn, Raymond Blundell, Katherine L. Bouman, Geoffrey C. Bower, Hope Boyce, Michael Bremer, Christiaan D. Brinkerink, Roger Brissenden, Silke Britzen, Dominique Broguiere, Thomas Bronzwaer, Sandra Bustamante, Do-Young Byun, John E. Carlstrom, Chiara Ceccobello, Chi-kwan Chan, Dominic O. Chang, Koushik Chatterjee, Shami Chatterjee, Ming-Tang Chen, Yongjun 永军 Chen 陈, Xiaopeng Cheng, Ilje Cho, Pierre Christian, Nicholas S. Conroy, John E. Conway, James M. Cordes, Thomas M. Crawford, Geoffrey B. Crew, Alejandro Cruz-Osorio, Yuzhu 玉竹 Cui 崔, Rohan Dahale, Jordy Davelaar, Mariafelicia De Laurentis, Roger Deane, Jessica Dempsey, Gregory Desvignes, Jason Dexter, Vedant Dhruv, Sheperd S. Doeleman, Sean Dougal, Sergio A. Dzib, Ralph P. Eatough, Razieh Emami, Heino Falcke, Joseph Farah, Vincent L. Fish, Ed Fomalont, H. Alyson Ford, Marianna Foschi, Raquel Fraga-Encinas, William T. Freeman, Per Friberg, Christian M. Fromm, Antonio Fuentes, Peter Galison, Charles F. Gammie, Roberto García, Olivier Gentaz, Boris Georgiev, Ciriaco Goddi, Roman Gold, Arturo I. Gómez-Ruiz, José L. Gómez, Minfeng 敏峰 Gu 顾, Mark Gurwell, Kazuhiro Hada, Daryl Haggard, Kari Haworth, Michael H. Hecht, Ronald Hesper, Dirk Heumann, Luis C. 子山 Ho 何, Paul Ho, Mareki Honma, Chih-Wei L. Huang, Lei 磊 Huang 黄, David H. Hughes, Shiro Ikeda
Abstract The Event Horizon Telescope (EHT) is a millimeter very long baseline interferometry (VLBI) array that has imaged the apparent shadows of the supermassive black holes M87* and Sagittarius A*. Polarimetric data from these observations contain a wealth of information on the black hole and accretion flow properties. In this work, we develop polarimetric geometric modeling methods for mm-VLBI data, focusing on approaches that fit data products with differing degrees of invariance to broad classes of calibration errors. We establish a fitting procedure using a polarimetric “m-ring” model to approximate the image structure near a black hole. By fitting this model to synthetic EHT data from general relativistic magnetohydrodynamic models, we show that the linear and circular polarization structure can be successfully approximated with relatively few model parameters. We then fit this model to EHT observations of M87* taken in 2017. In total intensity and linear polarization, the m-ring fits are consistent with previous results from imaging methods. In circular polarization, the m-ring fits indicate the presence of event-horizon-scale circular polarization structure, with a persistent dipolar asymmetry and orientation across several days. The same structure was recovered independently of observing band, used data products, and model assumptions. Despite this broad agreement, imaging methods do not produce similarly consistent results. Our circular polarization results, which imposed additional assumptions on the source structure, should thus be interpreted with some caution. Polarimetric geometric modeling provides a useful and powerful method to constrain the properties of horizon-scale polarized emission, particularly for sparse arrays like the EHT.
{"title":"Polarimetric Geometric Modeling for mm-VLBI Observations of Black Holes","authors":"Freek Roelofs, Michael D. Johnson, Andrew Chael, Michael Janssen, Maciek Wielgus, Avery E. Broderick, Kazunori Akiyama, Antxon Alberdi, Walter Alef, Juan Carlos Algaba, Richard Anantua, Keiichi Asada, Rebecca Azulay, Uwe Bach, Anne-Kathrin Baczko, David Ball, Mislav Baloković, John Barrett, Michi Bauböck, Bradford A. Benson, Dan Bintley, Lindy Blackburn, Raymond Blundell, Katherine L. Bouman, Geoffrey C. Bower, Hope Boyce, Michael Bremer, Christiaan D. Brinkerink, Roger Brissenden, Silke Britzen, Dominique Broguiere, Thomas Bronzwaer, Sandra Bustamante, Do-Young Byun, John E. Carlstrom, Chiara Ceccobello, Chi-kwan Chan, Dominic O. Chang, Koushik Chatterjee, Shami Chatterjee, Ming-Tang Chen, Yongjun 永军 Chen 陈, Xiaopeng Cheng, Ilje Cho, Pierre Christian, Nicholas S. Conroy, John E. Conway, James M. Cordes, Thomas M. Crawford, Geoffrey B. Crew, Alejandro Cruz-Osorio, Yuzhu 玉竹 Cui 崔, Rohan Dahale, Jordy Davelaar, Mariafelicia De Laurentis, Roger Deane, Jessica Dempsey, Gregory Desvignes, Jason Dexter, Vedant Dhruv, Sheperd S. Doeleman, Sean Dougal, Sergio A. Dzib, Ralph P. Eatough, Razieh Emami, Heino Falcke, Joseph Farah, Vincent L. Fish, Ed Fomalont, H. Alyson Ford, Marianna Foschi, Raquel Fraga-Encinas, William T. Freeman, Per Friberg, Christian M. Fromm, Antonio Fuentes, Peter Galison, Charles F. Gammie, Roberto García, Olivier Gentaz, Boris Georgiev, Ciriaco Goddi, Roman Gold, Arturo I. Gómez-Ruiz, José L. Gómez, Minfeng 敏峰 Gu 顾, Mark Gurwell, Kazuhiro Hada, Daryl Haggard, Kari Haworth, Michael H. Hecht, Ronald Hesper, Dirk Heumann, Luis C. 子山 Ho 何, Paul Ho, Mareki Honma, Chih-Wei L. Huang, Lei 磊 Huang 黄, David H. Hughes, Shiro Ikeda","doi":"10.3847/2041-8213/acff6f","DOIUrl":"https://doi.org/10.3847/2041-8213/acff6f","url":null,"abstract":"Abstract The Event Horizon Telescope (EHT) is a millimeter very long baseline interferometry (VLBI) array that has imaged the apparent shadows of the supermassive black holes M87* and Sagittarius A*. Polarimetric data from these observations contain a wealth of information on the black hole and accretion flow properties. In this work, we develop polarimetric geometric modeling methods for mm-VLBI data, focusing on approaches that fit data products with differing degrees of invariance to broad classes of calibration errors. We establish a fitting procedure using a polarimetric “m-ring” model to approximate the image structure near a black hole. By fitting this model to synthetic EHT data from general relativistic magnetohydrodynamic models, we show that the linear and circular polarization structure can be successfully approximated with relatively few model parameters. We then fit this model to EHT observations of M87* taken in 2017. In total intensity and linear polarization, the m-ring fits are consistent with previous results from imaging methods. In circular polarization, the m-ring fits indicate the presence of event-horizon-scale circular polarization structure, with a persistent dipolar asymmetry and orientation across several days. The same structure was recovered independently of observing band, used data products, and model assumptions. Despite this broad agreement, imaging methods do not produce similarly consistent results. Our circular polarization results, which imposed additional assumptions on the source structure, should thus be interpreted with some caution. Polarimetric geometric modeling provides a useful and powerful method to constrain the properties of horizon-scale polarized emission, particularly for sparse arrays like the EHT.","PeriodicalId":55567,"journal":{"name":"Astrophysical Journal Letters","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135515074","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-01DOI: 10.3847/2041-8213/ad0784
Shaosui Xu, Janet G. Luhmann, David L. Mitchell, Tristan Weber, David A. Brain, Yingjuan Ma, Shannon M. Curry, Gina A. DiBraccio, Jasper Halekas, Suranga Ruhunusiri, Christian Mazelle, Robert J. Lillis, Benoit Langlais
Abstract Mars’s magnetosphere is hybrid, having contributions from both an induced magnetosphere like Venus and the localized crustal magnetic fields. However, the planetary fields also include large-scale, more global components. In this study, we investigate their role in Mars’s magnetospheric topological responses to the interplanetary magnetic field (IMF) clock angle using observations from the Mars Atmospheric Volatile and EvolutioN mission. We show that the large-scale planetary field has a “dipole-like” influence on the Mars global magnetosphere by examining the open field topology. We find that the “dipole-like” planetary field, as at Earth, results in a more open magnetosphere during southward IMF. The clock angle effects on the twisted magnetotail current sheet are similarly consistent with this analogy. It reinforces the idea that Mars’s magnetosphere and solar wind interaction are more Earth-like than previously thought.
{"title":"Open Magnetic Fields in the Martian Magnetosphere Revealing Dipole-like Intrinsic Magnetic Fields at Mars","authors":"Shaosui Xu, Janet G. Luhmann, David L. Mitchell, Tristan Weber, David A. Brain, Yingjuan Ma, Shannon M. Curry, Gina A. DiBraccio, Jasper Halekas, Suranga Ruhunusiri, Christian Mazelle, Robert J. Lillis, Benoit Langlais","doi":"10.3847/2041-8213/ad0784","DOIUrl":"https://doi.org/10.3847/2041-8213/ad0784","url":null,"abstract":"Abstract Mars’s magnetosphere is hybrid, having contributions from both an induced magnetosphere like Venus and the localized crustal magnetic fields. However, the planetary fields also include large-scale, more global components. In this study, we investigate their role in Mars’s magnetospheric topological responses to the interplanetary magnetic field (IMF) clock angle using observations from the Mars Atmospheric Volatile and EvolutioN mission. We show that the large-scale planetary field has a “dipole-like” influence on the Mars global magnetosphere by examining the open field topology. We find that the “dipole-like” planetary field, as at Earth, results in a more open magnetosphere during southward IMF. The clock angle effects on the twisted magnetotail current sheet are similarly consistent with this analogy. It reinforces the idea that Mars’s magnetosphere and solar wind interaction are more Earth-like than previously thought.","PeriodicalId":55567,"journal":{"name":"Astrophysical Journal Letters","volume":"25 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135516057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-01DOI: 10.3847/2041-8213/ad0779
Jonathan Squire, Romain Meyrand, Matthew W. Kunz
Abstract A likely candidate mechanism to heat the solar corona and solar wind is low-frequency “Alfvénic” turbulence sourced by magnetic fluctuations near the solar surface. Depending on its properties, such turbulence can heat different species via different mechanisms, and the comparison of theoretical predictions to observed temperatures, wind speeds, anisotropies, and their variation with heliocentric radius provides a sensitive test of this physics. Here we explore the importance of normalized cross helicity, or imbalance, for controlling solar-wind heating, since it is a key parameter of magnetized turbulence and varies systematically with wind speed and radius. Based on a hybrid-kinetic simulation in which the forcing’s imbalance decreases with time—a crude model for a plasma parcel entrained in the outflowing wind—we demonstrate how significant changes to the turbulence and heating result from the “helicity barrier” effect. Its dissolution at low imbalance causes its characteristic features—strong perpendicular ion heating with a steep “transition-range” drop in electromagnetic fluctuation spectra—to disappear, driving a larger fraction of the energy into electrons and parallel ion heat, and halting the emission of ion-scale waves. These predictions seem to agree with a diverse array of solar-wind observations, offering to explain a variety of complex correlations and features within a single theoretical framework.
{"title":"Electron–Ion Heating Partition in Imbalanced Solar-wind Turbulence","authors":"Jonathan Squire, Romain Meyrand, Matthew W. Kunz","doi":"10.3847/2041-8213/ad0779","DOIUrl":"https://doi.org/10.3847/2041-8213/ad0779","url":null,"abstract":"Abstract A likely candidate mechanism to heat the solar corona and solar wind is low-frequency “Alfvénic” turbulence sourced by magnetic fluctuations near the solar surface. Depending on its properties, such turbulence can heat different species via different mechanisms, and the comparison of theoretical predictions to observed temperatures, wind speeds, anisotropies, and their variation with heliocentric radius provides a sensitive test of this physics. Here we explore the importance of normalized cross helicity, or imbalance, for controlling solar-wind heating, since it is a key parameter of magnetized turbulence and varies systematically with wind speed and radius. Based on a hybrid-kinetic simulation in which the forcing’s imbalance decreases with time—a crude model for a plasma parcel entrained in the outflowing wind—we demonstrate how significant changes to the turbulence and heating result from the “helicity barrier” effect. Its dissolution at low imbalance causes its characteristic features—strong perpendicular ion heating with a steep “transition-range” drop in electromagnetic fluctuation spectra—to disappear, driving a larger fraction of the energy into electrons and parallel ion heat, and halting the emission of ion-scale waves. These predictions seem to agree with a diverse array of solar-wind observations, offering to explain a variety of complex correlations and features within a single theoretical framework.","PeriodicalId":55567,"journal":{"name":"Astrophysical Journal Letters","volume":"111 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135609829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-01DOI: 10.3847/2041-8213/ad03f6
Domenico Trotta, Timothy S. Horbury, David Lario, Rami Vainio, Nina Dresing, Andrew Dimmock, Joe Giacalone, Heli Hietala, Robert F. Wimmer-Schweingruber, Lars Berger, Liu Yang
Abstract How thermal particles are accelerated to suprathermal energies is an unsolved issue, crucial for many astrophysical systems. We report novel observations of irregular, dispersive enhancements of the suprathermal particle population upstream of a high-Mach-number interplanetary shock. We interpret the observed behavior as irregular “injections” of suprathermal particles resulting from shock front irregularities. Our findings, directly compared to self-consistent simulation results, provide important insights for the study of remote astrophysical systems where shock structuring is often neglected.
{"title":"Irregular Proton Injection to High Energies at Interplanetary Shocks","authors":"Domenico Trotta, Timothy S. Horbury, David Lario, Rami Vainio, Nina Dresing, Andrew Dimmock, Joe Giacalone, Heli Hietala, Robert F. Wimmer-Schweingruber, Lars Berger, Liu Yang","doi":"10.3847/2041-8213/ad03f6","DOIUrl":"https://doi.org/10.3847/2041-8213/ad03f6","url":null,"abstract":"Abstract How thermal particles are accelerated to suprathermal energies is an unsolved issue, crucial for many astrophysical systems. We report novel observations of irregular, dispersive enhancements of the suprathermal particle population upstream of a high-Mach-number interplanetary shock. We interpret the observed behavior as irregular “injections” of suprathermal particles resulting from shock front irregularities. Our findings, directly compared to self-consistent simulation results, provide important insights for the study of remote astrophysical systems where shock structuring is often neglected.","PeriodicalId":55567,"journal":{"name":"Astrophysical Journal Letters","volume":"23 19","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135371435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-01DOI: 10.3847/2041-8213/ad07e2
Siddharth Gandhi, Sam de Regt, Ignas Snellen, Yapeng Zhang, Benson Rugers, Niels van Leur, Quincy Bosschaart
Abstract Isotope ratios have recently been measured in the atmospheres of directly imaged and transiting exoplanets from ground-based observations. The arrival of JWST allows us to characterize exoplanetary atmospheres in further detail and opens up wavelengths inaccessible from the ground. In this work we constrain the carbon and oxygen isotopes 13 C, 18 O, and 17 O from CO in the atmosphere of the directly imaged companion VHS 1256 b through retrievals of the ∼4.1–5.3 μ m NIRSpec G395H/F290LP observations from the early-release science program (ERS 1386). We detect and constrain 13 C 16 O, 12 C 18 O, and 12 C 17 O at 32 σ , 16 σ , and 10 σ confidence respectively, thanks to the very high signal-to-noise observations. We find the ratio of abundances are more precisely constrained than their absolute values, with <?CDATA ${}^{12}{rm{C}}{/}^{13}{rm{C}}={62}_{-2}^{+2}$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow /> <mml:mrow> <mml:mn>12</mml:mn> </mml:mrow> </mml:msup> <mml:mi mathvariant="normal">C</mml:mi> <mml:msup> <mml:mrow> <mml:mo stretchy="true">/</mml:mo> </mml:mrow> <mml:mrow> <mml:mn>13</mml:mn> </mml:mrow> </mml:msup> <mml:mi mathvariant="normal">C</mml:mi> <mml:mo>=</mml:mo> <mml:msubsup> <mml:mrow> <mml:mn>62</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>2</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>2</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> , in between previous measurements for companions (∼30) and isolated brown dwarfs (∼100). The oxygen isotope ratios are <?CDATA ${}^{16}{rm{O}}{/}^{18}{rm{O}}={425}_{-28}^{+33}$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow /> <mml:mrow> <mml:mn>16</mml:mn> </mml:mrow> </mml:msup> <mml:mi mathvariant="normal">O</mml:mi> <mml:msup> <mml:mrow> <mml:mo stretchy="true">/</mml:mo> </mml:mrow> <mml:mrow> <mml:mn>18</mml:mn> </mml:mrow> </mml:msup> <mml:mi mathvariant="normal">O</mml:mi> <mml:mo>=</mml:mo> <mml:msubsup> <mml:mrow> <mml:mn>425</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>28</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>33</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> and <?CDATA ${}^{16}{rm{O}}{/}^{17}{rm{O}}={1010}_{-100}^{+120}$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow /> <mml:mrow> <mml:mn>16</mml:mn> </mml:mrow> </mml:msup> <mml:mi mathvariant="normal">O</mml:mi> <mml:msup> <mml:mrow> <mml:mo stretchy="true">/</mml:mo> </mml:mrow> <mml:mrow> <mml:mn>17</mml:mn> </mml:mrow> </mml:msup> <mml:mi mathvariant="normal">O</mml:mi> <mml:mo>=</mml:mo> <mml:msubsup> <mml:mrow> <mml:mn>1010</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>100</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>120</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> . All of the ratios are lower than the local interstellar medium and solar system, suggesting that abundances
最近，在地面观测直接成像和过境系外行星的大气中测量了同位素比率。JWST的到来使我们能够更详细地描述系外行星的大气层，并打开了从地面无法到达的波长。在这项工作中，我们通过从早期释放科学计划(ERS 1386)中检索到的~ 4.1-5.3 μ m NIRSpec G395H/F290LP观测数据，约束了直接成像的伴星VHS 1256 b大气中CO的碳和氧同位素13 C, 18 O和17 O。由于高信噪比观测，我们分别在32 σ、16 σ和10 σ置信度下检测并约束了13c16o、12c18o和12c17o。我们发现，在之前对伴星(~ 30)和孤立褐矮星(~ 100)的测量之间，丰度比它们的绝对值更精确地受到约束，12 C / 13 C = 62−2 + 2。氧同位素比值为16 O / 18 O = 425−28 + 33和16 O / 17 O = 1010−100 + 120。所有这些比率都低于当地的星际介质和太阳系，这表明与主要同位素相比，次要同位素的丰度更高。这可能是由原行星盘中的同位素分馏作用驱动的，它可能通过同位素选择性光解作用、气体/冰分配和同位素交换反应潜在地改变碳和氧的比例。除了CO外，我们还限制了1h16o和12c16o(两种物种的主要同位素)，但只发现了12c1h4和14n1h3的上限。这项工作突出了JWST在约束系外行星大气同位素方面的能力，在确定未来的形成历史方面有很大的希望。
{"title":"JWST Measurements of <sup>13</sup>C, <sup>18</sup>O, and <sup>17</sup>O in the Atmosphere of Super-Jupiter VHS 1256 b","authors":"Siddharth Gandhi, Sam de Regt, Ignas Snellen, Yapeng Zhang, Benson Rugers, Niels van Leur, Quincy Bosschaart","doi":"10.3847/2041-8213/ad07e2","DOIUrl":"https://doi.org/10.3847/2041-8213/ad07e2","url":null,"abstract":"Abstract Isotope ratios have recently been measured in the atmospheres of directly imaged and transiting exoplanets from ground-based observations. The arrival of JWST allows us to characterize exoplanetary atmospheres in further detail and opens up wavelengths inaccessible from the ground. In this work we constrain the carbon and oxygen isotopes 13 C, 18 O, and 17 O from CO in the atmosphere of the directly imaged companion VHS 1256 b through retrievals of the ∼4.1–5.3 μ m NIRSpec G395H/F290LP observations from the early-release science program (ERS 1386). We detect and constrain 13 C 16 O, 12 C 18 O, and 12 C 17 O at 32 σ , 16 σ , and 10 σ confidence respectively, thanks to the very high signal-to-noise observations. We find the ratio of abundances are more precisely constrained than their absolute values, with <?CDATA ${}^{12}{rm{C}}{/}^{13}{rm{C}}={62}_{-2}^{+2}$?> <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\"> <mml:msup> <mml:mrow /> <mml:mrow> <mml:mn>12</mml:mn> </mml:mrow> </mml:msup> <mml:mi mathvariant=\"normal\">C</mml:mi> <mml:msup> <mml:mrow> <mml:mo stretchy=\"true\">/</mml:mo> </mml:mrow> <mml:mrow> <mml:mn>13</mml:mn> </mml:mrow> </mml:msup> <mml:mi mathvariant=\"normal\">C</mml:mi> <mml:mo>=</mml:mo> <mml:msubsup> <mml:mrow> <mml:mn>62</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>2</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>2</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> , in between previous measurements for companions (∼30) and isolated brown dwarfs (∼100). The oxygen isotope ratios are <?CDATA ${}^{16}{rm{O}}{/}^{18}{rm{O}}={425}_{-28}^{+33}$?> <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\"> <mml:msup> <mml:mrow /> <mml:mrow> <mml:mn>16</mml:mn> </mml:mrow> </mml:msup> <mml:mi mathvariant=\"normal\">O</mml:mi> <mml:msup> <mml:mrow> <mml:mo stretchy=\"true\">/</mml:mo> </mml:mrow> <mml:mrow> <mml:mn>18</mml:mn> </mml:mrow> </mml:msup> <mml:mi mathvariant=\"normal\">O</mml:mi> <mml:mo>=</mml:mo> <mml:msubsup> <mml:mrow> <mml:mn>425</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>28</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>33</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> and <?CDATA ${}^{16}{rm{O}}{/}^{17}{rm{O}}={1010}_{-100}^{+120}$?> <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\"> <mml:msup> <mml:mrow /> <mml:mrow> <mml:mn>16</mml:mn> </mml:mrow> </mml:msup> <mml:mi mathvariant=\"normal\">O</mml:mi> <mml:msup> <mml:mrow> <mml:mo stretchy=\"true\">/</mml:mo> </mml:mrow> <mml:mrow> <mml:mn>17</mml:mn> </mml:mrow> </mml:msup> <mml:mi mathvariant=\"normal\">O</mml:mi> <mml:mo>=</mml:mo> <mml:msubsup> <mml:mrow> <mml:mn>1010</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>−</mml:mo> <mml:mn>100</mml:mn> </mml:mrow> <mml:mrow> <mml:mo>+</mml:mo> <mml:mn>120</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> . All of the ratios are lower than the local interstellar medium and solar system, suggesting that abundances ","PeriodicalId":55567,"journal":{"name":"Astrophysical Journal Letters","volume":"18 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135714972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-30DOI: 10.3847/2041-8213/ad0380
Myles B. Sherman, Liam Connor, Vikram Ravi, Casey Law, Ge Chen, Kritti Sharma, Morgan Catha, Jakob T. Faber, Gregg Hallinan, Charlie Harnach, Greg Hellbourg, Rick Hobbs, David Hodge, Mark Hodges, James W. Lamb, Paul Rasmussen, Jun Shi, Dana Simard, Jean Somalwar, Reynier Squillace, Sander Weinreb, David P. Woody, Nitika Yadlapalli
Abstract Faraday rotation measures (RMs) of fast radio bursts (FRBs) offer the prospect of directly measuring extragalactic magnetic fields. We present an analysis of the RMs of 10 as yet nonrepeating FRBs detected and localized to host galaxies with robust redshift measurements by the 63-antenna prototype of the Deep Synoptic Array (DSA-110). We combine this sample with published RMs of 15 localized FRBs, nine of which are repeating sources. For each FRB in the combined sample, we estimate the host-galaxy dispersion measure (DM) contributions and extragalactic RM. We find compelling evidence that the extragalactic components of FRB RMs are often dominated by contributions from the host-galaxy interstellar medium (ISM). Specifically, we find that both repeating and as yet nonrepeating FRBs show a correlation between the host DM and host RM in the rest frame, and we find an anticorrelation between extragalactic RM (in the observer frame) and redshift for nonrepeaters, as expected if the magnetized plasma is in the host galaxy. Important exceptions to the ISM origin include a dense, magnetized circumburst medium in some repeating FRBs, and the intracluster medium of host or intervening galaxy clusters. We find that the estimated ISM magnetic-field strengths, B¯∣∣ , are characteristically ∼1–2 μ G larger than those inferred from Galactic radio pulsars. This suggests either increased ISM magnetization in FRB hosts in comparison with the Milky Way, or that FRBs preferentially reside in regions of increased magnetic-field strength within their hosts.
{"title":"Deep Synoptic Array Science: Implications of Faraday Rotation Measures of Fast Radio Bursts Localized to Host Galaxies","authors":"Myles B. Sherman, Liam Connor, Vikram Ravi, Casey Law, Ge Chen, Kritti Sharma, Morgan Catha, Jakob T. Faber, Gregg Hallinan, Charlie Harnach, Greg Hellbourg, Rick Hobbs, David Hodge, Mark Hodges, James W. Lamb, Paul Rasmussen, Jun Shi, Dana Simard, Jean Somalwar, Reynier Squillace, Sander Weinreb, David P. Woody, Nitika Yadlapalli","doi":"10.3847/2041-8213/ad0380","DOIUrl":"https://doi.org/10.3847/2041-8213/ad0380","url":null,"abstract":"Abstract Faraday rotation measures (RMs) of fast radio bursts (FRBs) offer the prospect of directly measuring extragalactic magnetic fields. We present an analysis of the RMs of 10 as yet nonrepeating FRBs detected and localized to host galaxies with robust redshift measurements by the 63-antenna prototype of the Deep Synoptic Array (DSA-110). We combine this sample with published RMs of 15 localized FRBs, nine of which are repeating sources. For each FRB in the combined sample, we estimate the host-galaxy dispersion measure (DM) contributions and extragalactic RM. We find compelling evidence that the extragalactic components of FRB RMs are often dominated by contributions from the host-galaxy interstellar medium (ISM). Specifically, we find that both repeating and as yet nonrepeating FRBs show a correlation between the host DM and host RM in the rest frame, and we find an anticorrelation between extragalactic RM (in the observer frame) and redshift for nonrepeaters, as expected if the magnetized plasma is in the host galaxy. Important exceptions to the ISM origin include a dense, magnetized circumburst medium in some repeating FRBs, and the intracluster medium of host or intervening galaxy clusters. We find that the estimated ISM magnetic-field strengths, <?CDATA ${bar{B}}_{| | }$?> <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\"> <mml:msub> <mml:mrow> <mml:mover accent=\"true\"> <mml:mrow> <mml:mi>B</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>¯</mml:mo> </mml:mrow> </mml:mover> </mml:mrow> <mml:mrow> <mml:mo stretchy=\"false\">∣</mml:mo> <mml:mo stretchy=\"false\">∣</mml:mo> </mml:mrow> </mml:msub> </mml:math> , are characteristically ∼1–2 μ G larger than those inferred from Galactic radio pulsars. This suggests either increased ISM magnetization in FRB hosts in comparison with the Milky Way, or that FRBs preferentially reside in regions of increased magnetic-field strength within their hosts.","PeriodicalId":55567,"journal":{"name":"Astrophysical Journal Letters","volume":"196 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136069471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-30DOI: 10.3847/2041-8213/ad0037
Odelia Teboul, Brian D. Metzger
Abstract Only a tiny fraction ∼1% of stellar tidal disruption events (TDEs) generate powerful relativistic jets evidenced by luminous hard X-ray and radio emissions. We propose that a key property responsible for both this surprisingly low rate and a variety of other observations is the typically large misalignment ψ between the orbital plane of the star and the spin axis of the supermassive black hole (SMBH). Such misaligned disk/jet systems undergo Lense–Thirring precession together about the SMBH spin axis. We find that TDE disks precess sufficiently rapidly that winds from the accretion disk will encase the system on large scales in a quasi-spherical outflow. We derive the critical jet efficiency η > η crit for both aligned and misaligned precessing jets to successfully escape from the disk wind ejecta. As η crit is higher for precessing jets, less powerful jets only escape after alignment with the SMBH spin. Alignment can occur through magneto-spin or hydrodynamic mechanisms, which we estimate occur on typical timescales of weeks and years, respectively. The dominant mechanism depends on η and the orbital penetration factor β . Hence, depending only on the intrinsic parameters of the event { ψ , η , β }, we propose that each TDE jet can either escape prior to alignment, thus exhibiting an erratic X-ray light curve and two-component radio afterglow (e.g., Swift J1644+57), or escape after alignment. Relatively rapid magneto-spin alignments produce relativistic jets exhibiting X-ray power-law decay and bright afterglows (e.g., AT2022cmc), while long hydrodynamic alignments give rise to late jet escape and delayed radio flares (e.g., AT2018hyz).
{"title":"A Unified Theory of Jetted Tidal Disruption Events: From Promptly Escaping Relativistic to Delayed Transrelativistic Jets","authors":"Odelia Teboul, Brian D. Metzger","doi":"10.3847/2041-8213/ad0037","DOIUrl":"https://doi.org/10.3847/2041-8213/ad0037","url":null,"abstract":"Abstract Only a tiny fraction ∼1% of stellar tidal disruption events (TDEs) generate powerful relativistic jets evidenced by luminous hard X-ray and radio emissions. We propose that a key property responsible for both this surprisingly low rate and a variety of other observations is the typically large misalignment ψ between the orbital plane of the star and the spin axis of the supermassive black hole (SMBH). Such misaligned disk/jet systems undergo Lense–Thirring precession together about the SMBH spin axis. We find that TDE disks precess sufficiently rapidly that winds from the accretion disk will encase the system on large scales in a quasi-spherical outflow. We derive the critical jet efficiency η > η crit for both aligned and misaligned precessing jets to successfully escape from the disk wind ejecta. As η crit is higher for precessing jets, less powerful jets only escape after alignment with the SMBH spin. Alignment can occur through magneto-spin or hydrodynamic mechanisms, which we estimate occur on typical timescales of weeks and years, respectively. The dominant mechanism depends on η and the orbital penetration factor β . Hence, depending only on the intrinsic parameters of the event { ψ , η , β }, we propose that each TDE jet can either escape prior to alignment, thus exhibiting an erratic X-ray light curve and two-component radio afterglow (e.g., Swift J1644+57), or escape after alignment. Relatively rapid magneto-spin alignments produce relativistic jets exhibiting X-ray power-law decay and bright afterglows (e.g., AT2022cmc), while long hydrodynamic alignments give rise to late jet escape and delayed radio flares (e.g., AT2018hyz).","PeriodicalId":55567,"journal":{"name":"Astrophysical Journal Letters","volume":"51 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136069819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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