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The dust properties of star-forming galaxies in the first billion years 形成恒星的星系在第一个十亿年内的尘埃特性
Proceedings of the International Astronomical Union Pub Date : 2021-08-01 DOI: 10.1017/S1743921322003866
E. da Cunha
{"title":"The dust properties of star-forming galaxies in the first billion years","authors":"E. da Cunha","doi":"10.1017/S1743921322003866","DOIUrl":"https://doi.org/10.1017/S1743921322003866","url":null,"abstract":"Abstract The Atacama Large Millimetre/Sub-millimetre Array (ALMA) is obtaining the deepest observations of early galaxies ever achieved at (sub-)millimetre wavelengths, and detecting the dust emission of young galaxies in the first billion years of cosmic history, well in the epoch of reionization. Here I review some of the latest results from these observations, with special focus on the REBELS large programme, which targets a sample of 40 star-forming galaxies at z ⋍ 7. ALMA detects significant amounts of dust in very young galaxies, and this dust might have different properties to dust in lower-redshift galaxies. I describe the evidence for this, and discuss theoretical/modelling efforts to explain the dust properties of these young galaxies. Finally, I describe two additional surprising results to come out of the REBELS survey: (i) a new population of completely dust-obscured galaxies at z ⋍ 7, and (ii) the prevalence of spatial offsets between the ultraviolet and infrared emission of UV-bright, high-redshift star-forming galaxies.","PeriodicalId":20590,"journal":{"name":"Proceedings of the International Astronomical Union","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86721469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
X-ray view of colliding winds in WR 25 wr25碰撞风的x射线图
Proceedings of the International Astronomical Union Pub Date : 2021-08-01 DOI: 10.1017/S1743921322004148
Bharti Arora, J. Pandey, M. De Becker
{"title":"X-ray view of colliding winds in WR 25","authors":"Bharti Arora, J. Pandey, M. De Becker","doi":"10.1017/S1743921322004148","DOIUrl":"https://doi.org/10.1017/S1743921322004148","url":null,"abstract":"Astract The long-term behavior of a colliding wind binary WR 25 is presented using archival X-ray data obtained over a time span of : 16 years. The present analysis reveals phase-locked variations repeating consistently over many consecutive orbits of the source (with binary orbital period : 208 days). A significant deviation of the X-ray flux with respect to the theoretical 1/D trend (D is the binary separation) close to periastron passage has been observed. This may occur due to the shifting of the adiabatic wind collision to the radiative regime in that part of the orbit. Further, no signature of X-ray emission in 10.0-79.0 keV energy range attributable to inverse Compton scattering is detected by NuSTAR.","PeriodicalId":20590,"journal":{"name":"Proceedings of the International Astronomical Union","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85882791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
The cold gas supply through cosmic time: insights on the galaxy assembly at early epochs 通过宇宙时间的冷气体供应:对早期星系集合的见解
Proceedings of the International Astronomical Union Pub Date : 2021-08-01 DOI: 10.1017/S1743921322003854
M. Aravena
{"title":"The cold gas supply through cosmic time: insights on the galaxy assembly at early epochs","authors":"M. Aravena","doi":"10.1017/S1743921322003854","DOIUrl":"https://doi.org/10.1017/S1743921322003854","url":null,"abstract":"Abstract. Remarkable progress has been made in the last few years in understanding the global properties of galaxies and how they evolve through cosmic time. Major focus has been given to studies of how the availability of molecular gas regulates star-forming activity and galaxy growth, the eventual quenching of star formation, and how these mechanisms evolve through cosmic time. Most of these advances have been made thanks to ALMA and the upgraded capabilities of NOEMA. In this contribution, I briey review the latest constraints on the molecular gas content based on dierent tracers of the interstellar medium (ISM; dust continuum and CO, [CI] and [CII] line emission), including recent determinations of the molecular gas fraction, gas depletion timescales, and molecular gas cosmic density provided by the recent ALMA programs out to z ∼ 7. Finally, I concentrate on recent and ongoing studies aiming to spatially and kinematically resolve the cold ISM and star formation activity down to kpc scales in galaxies out to z ∼ 6 – 7, which represent an unprecedented view of the galaxy assembly and feedback processes in the early universe.","PeriodicalId":20590,"journal":{"name":"Proceedings of the International Astronomical Union","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86243780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Radiatively Cooling Superwinds in Ultracompact Hii Regions 超紧凑Hii区域的辐射冷却超风
Proceedings of the International Astronomical Union Pub Date : 2021-08-01 DOI: 10.1017/S1743921322003994
Ashkbiz Danehkar
{"title":"Radiatively Cooling Superwinds in Ultracompact Hii Regions","authors":"Ashkbiz Danehkar","doi":"10.1017/S1743921322003994","DOIUrl":"https://doi.org/10.1017/S1743921322003994","url":null,"abstract":"Abstract Ultracompact Hii regions (UC-HII) are the young, very dense cores of massive star-forming regions in dwarf galaxies, where newly formed massive OB stars are surrounded by natal molecular clouds. Thermal energy deposited by mechanical feedback from a cluster of massive OB stars can form a superwind, which may lead to a wind-blown bubble as well as radiative cooling. We investigate the formation of radiatively cooling superwinds in UC-HII using a radiative cooling module in the hydrodynamics program. We built a grid of hydrodynamic simulations to determine the dependence of radiative cooling on the cluster radius, mass-deposition rate, wind velocity, and ambient medium in UC-HII. Our findings could help to better understand star formation in massive star-forming regions, where cool superwinds could trigger the formation of molecular clumpy regions.","PeriodicalId":20590,"journal":{"name":"Proceedings of the International Astronomical Union","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89816077","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Effect of stellar flares and coronal mass ejections on the atmospheric escape from hot Jupiters 恒星耀斑和日冕物质抛射对热木星大气逃逸的影响
Proceedings of the International Astronomical Union Pub Date : 2021-08-01 DOI: 10.1017/S1743921322004963
G. Hazra, A. Vidotto, S. Carolan, C. Villarreal D’Angelo, W. Manchester
{"title":"Effect of stellar flares and coronal mass ejections on the atmospheric escape from hot Jupiters","authors":"G. Hazra, A. Vidotto, S. Carolan, C. Villarreal D’Angelo, W. Manchester","doi":"10.1017/S1743921322004963","DOIUrl":"https://doi.org/10.1017/S1743921322004963","url":null,"abstract":"Abstract Spectral observations in the Ly-α line have shown that atmospheric escape is variable and for the exoplanet HD189733b, the atmospheric evaporation goes from undetected to enhanced evaporation in a 1.5 years interval. To understand the temporal variation in the atmospheric escape, we investigate the effect of flares, winds, and CMEs on the atmosphere of hot Jupiter HD189733b using 3D self-consistent radiation hydrodynamic simulations. We consider four cases: first, the quiescent phase including stellar wind; secondly, a flare; thirdly, a CME; and fourthly, a flare followed by a CME. We find that the flare alone increases the atmospheric escape rate by only 25%, while the CME leads to a factor of 4 increments, in comparison to the quiescent case. We also find that the flare alone cannot explain the observed high blue-shifted velocities seen in the Ly-α. The CME, however, leads to an increase in the velocity of escaping atmospheres, enhancing the blue-shifted transit depth.","PeriodicalId":20590,"journal":{"name":"Proceedings of the International Astronomical Union","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74527591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Weakening the wind with ULLYSES: Examining the Bi-Stability Jump 用尤利西斯削弱风:检查双稳定跳
Proceedings of the International Astronomical Union Pub Date : 2021-08-01 DOI: 10.1017/S174392132200480X
Olivier Verhamme, J. Sundqvist
{"title":"Weakening the wind with ULLYSES: Examining the Bi-Stability Jump","authors":"Olivier Verhamme, J. Sundqvist","doi":"10.1017/S174392132200480X","DOIUrl":"https://doi.org/10.1017/S174392132200480X","url":null,"abstract":"Abstract Radiation-driven mass-loss is an important, but still highly debated, driver for the evolution of massive stars. Current massive star evolution models rely on the theoretical prediction that low luminosity massive stars experience a sudden increase in mass loss below a stellar effective temperature of about 20 000 K. However, novel radiation-driven mass-loss rate predictions show no such bi-stability jump, which effects the post main-sequence evolution of massive stars. The ULLYSES data set provides a unique opportunity to investigate the theoretical bi-stability jump dichotomy and may help to assess the existence of the bi-stability jump in massive star winds. By utilising UV spectra from ULLYSES combined with X-shooter optical data we obtain empirical mass-loss rate constraints, that are no longer degenerate to the effects of wind clumping, and derive novel empirical constraints on the mass-loss behavior across the temperature range of the bi-stability jump. Current preliminary results do not show a clear presence of a bi-stability jump.","PeriodicalId":20590,"journal":{"name":"Proceedings of the International Astronomical Union","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79027105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Short-term variations of surface magnetism and prominences of the young sun-like star V530 Per 年轻的类太阳恒星V530 Per的表面磁性和日珥的短期变化
Proceedings of the International Astronomical Union Pub Date : 2021-08-01 DOI: 10.1051/0004-6361/202141975
Cang Tianqi, P. Petit, J. Donati, C. Folsom
{"title":"Short-term variations of surface magnetism and prominences of the young sun-like star V530 Per","authors":"Cang Tianqi, P. Petit, J. Donati, C. Folsom","doi":"10.1051/0004-6361/202141975","DOIUrl":"https://doi.org/10.1051/0004-6361/202141975","url":null,"abstract":"Abstract V530 Per is a solar-like member of the young open cluster α Persei, with an ultra-short rotation period (P∼0.32d). We report on two spectropolarimetric campaigns using ESPaDOnS, aimed at characterizing the short-term variability of its magnetic activity and large-scale magnetic field. We used time-resolved spectropolarimetric observations obtained in 2006 and 2018 and reconstructed the brightness distribution and large-scale magnetic field geometry of V530 Per through Zeeman-Doppler imaging. Using the same data sets, we also mapped the spatial distribution of prominences through tomography of Hα emission. We reconstruct, at both epochs, a large, dark spot occupying the polar region of V530 Per while smaller (dark and bright) spots were reconstructed at lower latitudes. The maximal field strength reached ∼1 kG. The prominence pattern displayed a stable component that was confined close to the corotation radius. In 2018, we also observed rapidly evolving Hα emitting structures, over timescales ranging from minutes to days. The fast Hα evolution was not linked to any detected photospheric changes in the spot or magnetic coverage.","PeriodicalId":20590,"journal":{"name":"Proceedings of the International Astronomical Union","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80970543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
The first detection of deuterated water toward extragalactic hot cores with ALMA 首次用ALMA探测到河外热核的氘化水
Proceedings of the International Astronomical Union Pub Date : 2021-08-01 DOI: 10.1017/S1743921322004252
M. Sewiło, A. Karska, L. Kristensen, S. Charnley, C.-H. Chen, Joana M. Oliveira, M. Cordiner, J. Wiseman, Á. Sánchez-Monge, J. V. van Loon, R. Indebetouw, P. Schilke, E. Garcia-Berrios
{"title":"The first detection of deuterated water toward extragalactic hot cores with ALMA","authors":"M. Sewiło, A. Karska, L. Kristensen, S. Charnley, C.-H. Chen, Joana M. Oliveira, M. Cordiner, J. Wiseman, Á. Sánchez-Monge, J. V. van Loon, R. Indebetouw, P. Schilke, E. Garcia-Berrios","doi":"10.1017/S1743921322004252","DOIUrl":"https://doi.org/10.1017/S1743921322004252","url":null,"abstract":"Abstract We discuss the first detection of deuterated water (HDO) in extragalactic hot cores. The HDO 211–212 line has been detected with the Atacama Large Millimeter/submillimeter Array (ALMA) toward hot cores N 105–2 A and 2 B in the N 105 star-forming region in the low-metallicity Large Magellanic Cloud (LMC), the nearest star-forming galaxy. We compared the HDO line luminosity (LHDO) measured toward two hot cores in N 105 to those observed toward a sample of 17 Galactic hot cores and found that the observed values of LHDO for the LMC hot cores fit very well into the LHDO trends with Lbol and metallicity observed toward the Galactic hot cores. Our results indicate that LHDO seems to be largely dependent on the source luminosity, but metallicity also plays a role. We provide a rough estimate of the H2O column density and abundance ranges toward N 105–2 A and 2 B by assuming that HDO/H2O toward the LMC hot cores is the same as that observed in the Milky Way; the obtained values are systematically lower than those measured in the Galactic hot cores. The spatial distribution and velocity structure of the HDO emission in N 105–2 A is consistent with HDO being the product of the low-temperature dust grain chemistry.","PeriodicalId":20590,"journal":{"name":"Proceedings of the International Astronomical Union","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75441071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
The spatially resolved view of star formation in galaxy clusters 星系团中恒星形成的空间分辨视图
Proceedings of the International Astronomical Union Pub Date : 2021-08-01 DOI: 10.1017/S1743921322004884
B. Poggianti
{"title":"The spatially resolved view of star formation in galaxy clusters","authors":"B. Poggianti","doi":"10.1017/S1743921322004884","DOIUrl":"https://doi.org/10.1017/S1743921322004884","url":null,"abstract":"Abstract Integral field spectroscopic studies of galaxies in dense environments, such as clusters and groups of galaxies, have provided new insights for understanding how star formation proceeds, and quenches. I present the spatially resolved view of the star formation activity and its link with the multiphase gas in cluster galaxies based on MUSE and multi-wavelength data of the GASP survey. I discuss the link among the different scales (i.e. the link between the spatially resolved and the global star formation rate-stellar mass relation), the spatially resolved signatures and the quenching histories of jellyfish (progenitors) and post-starburst (descendants) galaxies in clusters. Finally, I discuss the multi-wavelength view of star-forming clumps both in galaxy disks and in the tails of stripped gas.","PeriodicalId":20590,"journal":{"name":"Proceedings of the International Astronomical Union","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86211517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
ALMA observations of the environments of G333.0162+00.7615 ALMA对G333.0162+00.7615环境的观测
Proceedings of the International Astronomical Union Pub Date : 2021-08-01 DOI: 10.1017/S1743921323000121
T. Komesh, Aruzhan Omar, G. Garay, Zhandos Assembay, N. Alimgazinova, Nurman Zhumabay, Meiramgul Kyzgarina
{"title":"ALMA observations of the environments of G333.0162+00.7615","authors":"T. Komesh, Aruzhan Omar, G. Garay, Zhandos Assembay, N. Alimgazinova, Nurman Zhumabay, Meiramgul Kyzgarina","doi":"10.1017/S1743921323000121","DOIUrl":"https://doi.org/10.1017/S1743921323000121","url":null,"abstract":"Abstract We have carried out ALMA observations toward the environments of G333.0162+00.7615 which was considered as a candidate of high-mass young stellar object (HMYSO) in previous studies. Our dust continuum, molecular line emission and radio recombination line emission observations show that this source is not HMYSO associated with hypercompact (HC) HII regions. Instead, we discovered two new hot cores associate with earliest stages of high mass star formation region. We estimated the rotational temperatures of these cores about 270 K from J=14→13 rotational transition of CH3CN ladder. The moment maps show velocity gradients confirming that this cores are rotating.","PeriodicalId":20590,"journal":{"name":"Proceedings of the International Astronomical Union","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77022085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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