Accretion Disks Around Young Massive Stars

年轻大质量恒星周围的吸积盘

• 批准号: 0098524
• 负责人: Peter Hofner
• 金额: $ 18.8万
• 依托单位: University of Puerto Rico-Rio Piedras
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-06-01 至 2004-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0098524&HistoricalAwards=false
• 关键词: Accretion; Disks; Around; Young; Massive

" Accretion Disks Around Young Massive Stars"AST- 0098524Massive stars are responsible for many of the basic characteristics of spiral galaxies. They effectively dictate the properties of the interstellar medium through their strong ionizing radiation, vigorous outflowing winds and eventual demise as supernovae explosions. They also influence the formation of subsequent generations of stars by triggering the initial collapse of cloud cores of molecular dust and gas. The dominant mechanism by which high mass stars form remains one of the outstanding problems of stellar astrophysics. Most likely, the mechanism is similar to that which produces low mass stars through the formation and collapse of protostellar disks. But, in the case of massive stars, there must be important modifications to the star forming process brought on by the enormous radiation pressure from the massive protostars. The possibility exists that there is an alternative route for producing stars in the high-mass range but first it is important to look hard for the signatures of disks. Through this award the PI will turn to radio astronomy and exploit the capabilities of the Very Large Array (VLA) and the Very Large Baseline Array to search for and subsequently study disks of this type. The VLA will be used to directly image the dust continuum emission from the accretion disk at a wavelength of 7 mm. The VLBA will be used to identify accretion disks in another way, via the strong water maser line at a wavelength of 1.3 cm and to use this as a kinetic probe. Whether the accretion disks are detected or not, the proposed observations will provide high angular resolution observations of matter in the vicinity of young massive stars.

“围绕年轻大型恒星的积聚磁盘” AST- 0098524量恒星负责螺旋星系的许多基本特征。他们通过强烈的电离辐射，剧烈的散发风和最终作为超新星爆炸的灭亡来有效地决定星际介质的特性。它们还通过触发分子灰尘和气体的云核的初始崩溃来影响随后的恒星的形成。高质量恒星形成的主要机制仍然是恒星天体物理学的重大问题之一。最有可能的机制与通过原恒星磁盘的形成和崩溃产生低质量恒星的机制相似。但是，在巨大的恒星的情况下，必须对恒星形成过程进行重要的修改，这是由巨大的质恒星带来的巨大辐射压力所带来的。存在在高质量范围内生产恒星的另一种途径的可能性，但首先，要努力识别磁盘的签名很重要。通过这个奖项，PI将转向射电天文学，并利用非常大的阵列（VLA）的功能以及非常大的基线阵列来搜索此类磁盘，然后研究此类磁盘。 VLA将用于直接以7毫米的波长从积聚磁盘中粉尘连续发射。 VLBA将通过强大的水层线以1.3 cm的长度来以另一种方式识别吸积盘，并将其用作动力学探针。无论是否检测到吸积盘，所提出的观察结果都将提供高角度分辨率的观测值，对年轻大型恒星附近的物质进行观察。