A giant molecular cloud falling through the heart of Cygnus A: clues to the triggering of the activity
نویسنده
چکیده
We present intermediate resolution near-IR long-slit spectroscopic data for the nearby radio galaxy Cygnus A (3C 405) (obtained with the NIRSPEC spectrograph on the Keck II telescope). The data reveal considerable complexity in the near-IR emission line kinematics, including line splittings of 200-350 km s and a mixture of narrow (FWHM ∼200 km s) and broad (FWHM ∼700 km s) components to the emission lines. It is notable that the Paα and H2 emission lines show markedly different kinematics, both onand off-nucleus. Overall, the data provide evidence for the presence of a giant molecular cloud falling through the heart of the Cygnus A host galaxy, the motion of which is not driven by the AGN itself. We suggest that this cloud may be connected to the triggering of the activity in this highly powerful AGN. We also detect split H2 components on the nucleus that are likely to originate in the circum-nuclear torus.
منابع مشابه
Investigation Giant Placental Chorioangioma Associated with Neonatal Sepsis-like Disease: A Case Report
Giant chorioangioma is a placental tumor associated with gestational complications such as preeclampsia, polyhydramnios and hemorrhage. In addition, this tumor might lead to the incidence of non-immune fetal hydrops, heart failure, anemia, thrombocytopenia, weight loss and death among neonates. In this case report, the clinical image of a term newborn (weighing 2800 g) with one-minute Apgar sco...
متن کاملThe Comparative Effect of Teaching Grammar through Interpretation Tasks and Pictorial Clues on EFL Learners’ Writing Accuracy
The focus of this study is to investigate the comparative effect of teaching grammar through interpretation tasks and pictorial clues on EFL learners’ writing accuracy. The participants were 60 female intermediate EFL learners with age range of 21-35 who were divided into two experimental groups after being homogenized by a piloted PET test. In the piloted researcher-made pre-test, the research...
متن کاملA Comparative Analysis of Genetic Diversity and Structure of Whooper Swan (Cygnus cygnus): A New Considerable Established Population in Iran
New wintering populations of Whooper Swan have been recently reported from west Asia, a lack of information about the population and its origin. The understanding the genetic structure and connectivity are crucial for determining strategies of management for its conservation programs. The samples were collected from two populations in northern Iran, Finland, Sweden, and Iceland, where with larg...
متن کاملSynergistic Effects of Arsenic Trioxide and Radiation: Triggering the Intrinsic Pathway of Apoptosis
Background: Arsenic trioxide (ATO) has been reported as an effective anti-cancer and a US Food and Drug Administration (FDA) approved drug for treatment of some cancers. The aim of this study is to determine the underlying apoptosis molecular and cellular mechanisms of ATO in the presence or absence of ionizing radiation (IR) in vitro in the glioblastoma multiforme (GBM) cell line, U87MG. Metho...
متن کاملGiant LV Thrombose and Thrombosed Coronary Aneurysm in an Infant with Kawasaki Disease
Background Kawasaki disease (KD) also known as mucocutaneous lymph node syndrome is the febrile and self-limited vasculitis that occurs in children of all ages, especially younger than five years of age. Here, we describe a case of Kawasaki disease with coronary artery aneurysm and a big clot in LV with a diameter of 1.5 cm. <stron...
متن کامل