7 research outputs found
Powerful Yet Lonely: Is 3C 297 a High-redshift Fossil Group?
The environment of the high-redshift (z = 1.408), powerful radio-loud galaxy 3C 297 has several distinctive features of a galaxy cluster. Among them, a characteristic halo of hot gas revealed by Chandra X-ray observations. In addition, a radio map obtained with the Very Large Array shows a bright hotspot in the northwestern direction, created by the interaction of the active galactic nucleus (AGN) jet arising from 3C 297 with its environment. In the X-ray images, emission cospatial with the northwestern radio lobe is detected, and peaks at the position of the radio hotspot. The extended, complex X-ray emission observed with our new Chandra data is largely unrelated to its radio structure. Despite having attributes of a galaxy cluster, no companion galaxies have been identified from 39 new spectra of neighboring targets of 3C 297 obtained with the Gemini Multi-Object Spectrograph. None of the 19 galaxies for which a redshift was determined lies at the same distance as 3C 297. The optical spectral analysis of the new Gemini spectrum of 3C 297 reveals an isolated Type II radio-loud AGN. We also detected line broadening in [O ii] λ3728 with a FWHM about 1700 km s−1 and possible line shifts of up to 500–600 km s−1. We postulate that the host galaxy of 3C 297 is a fossil group, in which most of the stellar mass has merged into a single object, leaving behind an X-ray halo
Correlation between ETFDH mutations and dysregulation of serum myomiRs in MADD patients
Multiple acyl-CoA dehydrogenase deficiency (MADD) is a rare fatty acids oxidation disorder which is often associated with deficiency of electron transfer flavoprotein dehydrogenase (ETFDH). In this study we reported clinical features and evaluation of expression profile of circulating muscle-specific miRNAs (myomiRs) in two MADD patients carrying different ETFDH gene mutations. Patient 1 was a compound heterozygote for two missense mutations. She showed a late onset MADD clinical phenotype and a significant increase of serum myomiRs. Patient 2, carrying a missense and a frameshift mutation, displayed early onset symptoms and a slight increase of some serum myomiRs
UN System. Temi e problemi di storia internazionale
In questo volume collettaneo sono analizzati temi e problemi dello UN System nella configurazione che ha assunto storicamente dal 1945 a oggi. Il volume è frutto della collaborazione fra studiosi di diversa collocazione accademica e scientifica, ciascuno specialista dei temi affrontati. Presi nel loro insieme, i risultati qui presentati concorrono all’analisi e alla ricostruzione della complessa rete di rapporti tra l’ONU e le altre dimensioni dello UN System, e delle trasformazioni del loro ruolo nella comunità internazionale in cui operano
The Chandra 3C Snapshot Survey for Sources with z < 1
<p>The 3CR catalogue is one of the best studied sample of radio-loud active galaxies, spanning a wide range of redshifts and radio powers and being unbiased with respect to X-ray observations. We are completing the Chandra Snapshot Survey of the 3CR catalog. Preliminary results on the extension of the X-ray observations in the 0.5-1 redshift range are presented here. We compared Chandra observations with radio maps to search for extended emission associated with jets, hotspots and galaxy clusters. We found the X-ray radiation arising from the intergalactic medium in one galaxy cluster and we detected three hostpots in the Chandra images. X-ray emission from the core of all radio galaxies in our sample was also found, seven of them also showing extended X-ray emission around their nuclei. </p
Extended X-ray emission around FR II radio galaxies: hotspots, lobes and galaxy clusters
We present a systematic analysis of the extended X-ray emission discovered around 35 FR II radio galaxies from the revised Third Cambridge catalog (3CR) Chandra Snapshot Survey with redshifts between 0.05 to 0.9. We aimed to (i) test for the presence of extended X-ray emission around FR II radio galaxies, (ii) investigate if the extended emission origin is due to Inverse Compton scattering of seed photons arising from the Cosmic Microwave Background (IC/CMB) or to thermal emission from an intracluster medium (ICM) and (iii) test the impact of this extended emission on hotspot detection. We investigated the nature of the extended X-ray emission by studying its morphology and compared our results with low-frequency radio observations (i.e., ∼150 MHz), in the TGSS and LOFAR archives, as well as with optical images from Pan-STARRS. In addition, we optimized a search for X-ray counterparts of hotspots in 3CR FR II radio galaxies. We found statistically significant extended emission (>3σ confidence level) along the radio axis for ∼90%, and in the perpendicular direction for ∼60% of our sample. We confirmed the detection of 7 hotspots in the 0.5 - 3 keV. In the cases where the emission in the direction perpendicular to the radio axis is comparable to that along the radio axis, we suggest that the underlying radiative process is thermal emission from ICM. Otherwise, the dominant radiative process is likely non-thermal IC/CMB emission from lobes. We found that non-thermal IC/CMB is the dominant process in ∼70% of the sources in our sample, while thermal emission from the ICM dominates in ∼15% of them