Support for observing at the JCMT: SCUBA-2 shared risks observing of Perseus (project M09BI127)

支持 JCMT 观测：SCUBA-2 共享英仙座观测风险（项目 M09BI127）

• 批准号: ST/I000356/1
• 负责人: John Richer
• 金额: $ 0.19万
• 依托单位: University of Cambridge
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2010
• 资助国家: 英国
• 起止时间: 2010 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=ST%2FI000356%2F1
• 关键词: Support; observing; JCMT; SCUBA; shared

Despite their different initial and internal conditions, the mass distribution of stars in most stellar clusters (typically called the initial mass function or IMF) are remarkably similar. Furthermore around a decade ago it was shown that the mass distribution of the youngest stars and stellar precursors (often called the core mass function or CMF), follows the same shape as the IMF. This has proved an important constraint for theoreticians modelling the formation of stars: they must recover this distribution of object masses at all stages in their simulations. Probing the similarity between the CMF and IMF further has been hindered by the limitations in previous instrumentation ensuring large and/or sensitive maps take a prodigious amount of time. SCUBA-2 on the James Clerk Maxwell telescope (JCMT) will be many hundreds of times faster at mapping the sky than previous instruments, allowing astronomers to make vast maps surveying the sky. Our project aims to use SCUBA-2 to measure the CMF at brown-dwarf masses for the first time - regions where we do not know the shape of CMF. Will the shape of the CMF continue to mirror that of the IMF - implying low-mass stellar cores form in the same way as brown dwarf stars? In fact the cores we discover at low masses will be a new and unique population probably the youngest objects that will go on to be stars identified to date. The velocity and density conditions in these objects crucially set the details of the ensuing collapse to form a star. We have been awarded 10 hours of telescope time with SCUBA-2 during the recent shared-risk call to address these questions in a nearby cloud of dust and gas (towards the Perseus constellation) that is known to be forming stars. The unprecedented sensitivity and mapping speed of SCUBA-2 will allow us to find cores approximately 50 times lighter than seen before in this region. We request support for one observer (the PI of the SCUBA-2 project) to travel to Hawaii to undertake our highly-ranked observations. The trip includes a day spent at the Joint Astronomy Centre (JAC) before the run for the observer to become familiar with the software and data reduction, as recommended by JAC staff. An in-person trip is essential to develop the optimum observing strategy and data reduction procedures with SCUBA-2, which are currently unclear given it is such a new and complex instrument.

尽管它们的初始条件不同，但在大多数恒星簇（通常称为初始质量函数或IMF）中，恒星的质量分布非常相似。此外，大约十年前，最年轻的恒星和恒星前体的质量分布（通常称为核心质量函数或CMF）与IMF相同的形状。这证明了对恒星形成的理论家的重要限制：他们必须在模拟中的所有阶段恢复对物体质量的分布。在先前的仪器中的局限性确保大型和/或敏感地图需要大量的时间，探测CMF和IMF之间的相似性进一步阻碍了。 James Clerk Maxwell望远镜（JCMT）上的水肺2比以前的乐器要比以前的乐器快数百次，这使天文学家可以制作大量的地图来调查天空。我们的项目旨在首次使用Scuba-2在棕色贫民窟的群众处测量CMF - 我们不知道CMF形状的区域。 CMF的形状是否会继续反映出IMF的形状 - 暗示与棕色矮星相同的低质量恒星芯形成？实际上，我们在低群众发现的核心将是一个新的，独特的人群，这可能是迄今为止被确定为恒星的最年轻物体。这些物体中的速度和密度条件至关重要地设置了随后崩溃的细节以形成恒星。在最近的共享风险呼叫中，我们被授予了10个小时的望远镜时间，以在附近的灰尘和天然气云（朝着Perseus Constellation）中解决这些问题，该问题已知是恒星。 Scuba-2的前所未有的灵敏度和映射速度将使我们找到比以前在该区域低约50倍的核心。我们要求支持一个观察者（Scuba-2项目的PI）前往夏威夷进行我们排名高的观察结果。这次旅行包括在跑步之前在联合天文学中心（JAC）度过的一天，以供观察者熟悉JAC员工的熟悉软件和数据减少。面对面的旅行对于使用Scuba-2制定最佳观察策略和数据减少程序至关重要，因为这是一种新颖而复杂的仪器，目前尚不清楚。