CAREER: The Physics and Cosmology of TeV Blazars

银河系外的宇宙拥有丰富的来源，这些来源与宇宙中最强大的持久现象有关：吸积形成活动星系核(AGN)的超大质量黑洞。许多活动星系核从它们的黑洞附近发射出相对论的孪生等离子喷流，当它们靠近观察者的视线时，就会产生一类活动星系核，称为blazar。费米卫星和地面成像切伦科夫望远镜的观测表明，许多blazar是太电子伏能量(TeV)的伽马射线的巨大来源。然而，它们对宇宙能量学的影响以前一直被认为是微弱的，因为它们的发光输出在宇宙总辐射功率中只是一个很小的组成部分。然而，PI和他的合作者最近的研究表明，TeV Blazar实际上是非凡的能量来源。通过研究双光束(来自TeV blazar的光子与河外背景光光子相遇时产生的电子-正电子对)，PI认为blazar是红移2-3的星际介质(IGM)中的主要热源。这将对宇宙的演化产生重大影响。PI将对TeV blazar的宇宙学含义进行详细分析，这将涉及天体物理的许多不同领域：从线性等离子体不稳定性，到弱湍流和热化，到IGM的热力学，以及星系和星系团的形成。他将(1)研究极端相对论双光束的等离子体物理，(2)在宇宙学的背景下设置blazar加热，(3)探索他的工作对宇宙结构形成的影响。PI将以多种方式向广大观众传播他的研究。首先，他将重新设想威斯康星大学密尔沃基分校(UWM)的入门物理课程，将传统讲座与在线视频课程和练习相结合。他还将与威斯康星大学的天文俱乐部密切合作，为学期和暑期研究项目招募本科生和高中教师。最后，PI将通过在附近的曼弗雷德·奥尔森天文馆制作和发表AstroBreak系列节目来进行公共宣传。

The extragalactic universe is abundant with sources that are associated with the most powerful persistent phenomenon in the universe: accreting supermassive black holes that form Active Galactic Nuclei (AGN). Numerous AGN launch relativistic twin jets of plasma from the immediate vicinity of their black holes which, when oriented close to the line of sight to the observer, give rise to a class of AGN named blazars. Observations by the Fermi satellite and ground based imaging Cerenkov telescopes show that many blazars are prodigious sources of gamma-rays at tera-electronvolt (TeV) energies. Their impact on the energetics of the universe, however, has previously been thought to be slim since their luminous output is a minor component of the total radiative power in the universe. However, recent work by the PI and his collaborators suggest that TeV blazars are, in fact, remarkable sources of energy. By studying pair beams (electron-positron pairs that are produced when photons from TeV blazars meet extragalactic background light photons) the PI argues that blazars are the dominant heat source in the intergalactic medium (IGM) at redshifts 2-3. This would have substantial implications for the evolution of the universe.The PI will perform a detailed analysis of the cosmological implications of TeV blazars, which will touch on many different areas of astrophysics: from linear plasma instabilties, to weak turbulence and thermalization, to thermodynamics of the IGM, and to the formation of galaxies and clusters. He will (1) investigate the plasma physics of ultrarelativistic pair beams, (2) set blazar heating in a cosmological context, and (3) explore the implications of his work for the structure formation of the universe.The PI will disseminate his research to a broad audience in numerous ways. First, he will reimagine introductory physics classes at the University of Wisconsin-Milwaukee (UWM), by combining traditional lectures with online video lessons and exercises. He will also work closely with the Astronomy Club at UWM by recruiting undergraduates and high school teachers for semester and summer research projects. Finally, the PI will perform public outreach by producing and giving public lectures through the Astrobreak series at the nearby Manfred Olson planetarium.