GOODS-Herschel: radio-excess signature of hidden AGN activity in distant star-forming galaxies

Context. A tight correlation exists between far-infrared and radio emission for star-forming galaxies (SFGs), which seems to hold out to high redshifts (z ≈ 2). Any excess of radio emission over that expected from star formation processes is most likely produced by an active galactic nucleus (AGN), often hidden by large amounts of dust and gas. Identifying these radio-excess sources will allow us to study a population of AGN unbiased by obscuration and thus find some of the most obscured, Compton-thick AGN, which are in large part unidentified even in the deepest X-ray and infrared (IR) surveys. Aims. We present here a new spectral energy distribution (SED) fitting approach that we adopt to select radio-excess sources amongst distant star-forming galaxies in the GOODS-Herschel (North) field and to reveal the presence of hidden, highly obscured AGN. Methods. Through extensive SED analysis of 458 galaxies with radio 1.4 GHz and mid-IR 24 μm detections using some of the deepest Chandra X-ray, Spitzer and Herschel infrared, and VLA radio data available to date, we have robustly identified a sample of 51 radio-excess AGN (~1300 deg^(-2)) out to redshift z ≈ 3. These radio-excess AGN have a significantly lower far-IR/radio ratio (q < 1.68, 3σ) than the typical relation observed for star-forming galaxies (q ≈ 2.2). Results. We find that ≈45% of these radio-excess sources have a dominant AGN component in the mid-IR band, while for the remainders the excess radio emission is the only indicator of AGN activity. The presence of an AGN is also confirmed by the detection of a compact radio core in deep VLBI 1.4 GHz observations for eight of our radio-excess sources (≈16%; ≈66% of the VLBI detected sources in this field), with the excess radio flux measured from our SED analysis agreeing, to within a factor of two, with the radio core emission measured by VLBI. We find that the fraction of radio-excess AGN increases with X-ray luminosity reaching ~60% at L_X ≈ 10^(44)−10^(45) erg s^(-1), making these sources an important part of the total AGN population. However, almost half (24/51) of these radio-excess AGN are not detected in the deep Chandra X-ray data, suggesting that some of these sources might be heavily obscured. Amongst the radio-excess AGN we can distinguish three groups of objects: i) AGN clearly identified in infrared (and often in X-rays), a fraction of which are likely to be distant Compton-thick AGN; ii) moderate luminosity AGN (L_X ≲ 10^(43) erg s^(-1)) hosted in strong star-forming galaxies; and iii) a small fraction of low accretion-rate AGN hosted in passive (i.e. weak or no star-forming) galaxies. We also find that the specific star formation rates (sSFRs) of the radio-excess AGN are on average lower that those observed for X-ray selected AGN hosts, indicating that our sources are forming stars more slowly than typical AGN hosts, and possibly their star formation is progressively quenching

Space-time segmentation method for study of the vertical structure and evolution of solar supergranulation from data provided by local helioseismology

Solar supergranulation remains a mystery in spite of decades of intensive studies. Most of the papers about supergranulation deal with its surface properties. Local helioseismology provides an opportunity to look below the surface and see the vertical structure of this convective structure. We present a concept of a (3+1)-D segmentation algorithm capable of recognising individual supergranules in a sequence of helioseismic 3-D flow maps. As an example, we applied this method to the state-of-the-art data and derived descriptive statistical properties of segmented supergranules -- typical size of 20--30 Mm, characteristic lifetime of 18.7 hours, and estimated depth of 15--20 Mm. We present preliminary results obtained on the topic of the three-dimensional structure and evolution of supergranulation. The method has a great potential in analysing the better data expected from the helioseismic inversions, which are being developed.Comment: 6 pages, 4 figures, accepted in New Astronom

PROPERTIES AND CONTROL OF FLUXES FOR INGOT CASTING AND CONTINUOUS CASTING

Present chemical-physical characteristics of ingot and continuous casting powders can be critically evaluated pointing out history of invention of these materials. In an original tone, pioneering nature of first developments of casting powders will be described, illustrating empirical know-how of casting powders technology, based on trial-and-error method. It will be originally emphasized that technology of continuous casting powders derives directly from studies and developments followed for ingot casting setting-up. Latest developments will be analysed in terms of the value innovation business model

The Nustar Extragalactic Surveys: Initial Results and Catalog from the Extended Chandra Deep Field South

We present initial results and the source catalog from the NuSTAR survey of the Extended Chandra Deep Field South (hereafter, ECDFS) - currently the deepest contiguous component of the NuSTAR extragalactic survey program. The survey covers the full ~30 arcmin x 30 arcmin area of this field to a maximum depth of ~360 ks (~220 ks when corrected for vignetting at 3-24 keV), reaching sensitivity limits of ~1.3 x 10^-14 erg/cm2/s (3-8 keV), ~3.4 x 10^-14 erg/cm2/s (8-24 keV) and ~3.0 x 10^-14 erg/cm2/s (3-24 keV). Fifty four (54) sources are detected over the full field, although five of these are found to lie below our significance threshold once contaminating flux from neighboring (i.e., blended) sources is taken into account. Of the remaining 49 that are significant, 19 are detected in the 8-24 keV band. The 8-24 keV to 3-8 keV band ratios of the twelve sources that are detected in both bands span the range 0.39-1.7, corresponding to a photon index range of Gamma ~ 0.5-2.3, with a median photon index of 1.70 +/- 0.52. The redshifts of the 49 sources in our main sample span the range z = 0.21-2.7, and their rest-frame 10-40 keV luminosities (derived from the observed 8-24 keV fluxes) span the range L(10-40 keV) ~ (0.7-300) x 10^43 erg/s, sampling below the knee of the X-ray luminosity function out to z ~ 0.8-1. Finally, we identify one NuSTAR source that has neither a Chandra nor an XMM-Newton counterpart, but that shows evidence of nuclear activity at infrared wavelengths, and thus may represent a genuine, new X-ray source detected by NuSTAR in the ECDFS

A prototype of a large tunable Fabry–Pérot interferometer for solar spectroscopy

Large Fabry-Pérot Interferometers (FPIs) are used in a variety of astronomical instrumentation, including spectro-polarimeters for 4 m class solar telescopes. In this work we comprehensively characterize the cavity of a prototype 150 mm FPI, sporting a novel, fully symmetric design. Of particular interest, we define a new method to properly assess the gravity effects on the interferometer's cavity when the system is used in either the vertical or horizontal configuration, both typical of solar observations. We show that the symmetric design very effectively limits the combined effects of pre-load and gravity forces to only a few nm over a 120 mm diameter illuminated surface, with gravity contributing ~2 nm peak-to-valley (~0.3 nm rms) in either configuration. We confirm a variation of the tilt between the plates of the interferometer during the spectral scan, which can be mitigated with appropriate corrections to the spacing commands. Finally, we show that the dynamical response of the new system fully satisfies typical operational scenarios. We conclude that large, fully symmetric FPIs can be safely used within solar instrumentation in both, horizontal and vertical position, with the latter better suited to limiting the overall volume occupied by such an instrument

X-ray bolometric corrections for Compton-thick active galactic nuclei

We present X-ray bolometric correction factors, $\kappa_{Bol}$ ($\equiv L_{Bol}/L_X$), for Compton-thick (CT) active galactic nuclei (AGN) with the aim of testing AGN torus models, probing orientation effects, and estimating the bolometric output of the most obscured AGN. We adopt bolometric luminosities, $L_{Bol}$, from literature infrared (IR) torus modeling and compile published intrinsic 2--10 keV X-ray luminosities, $L_{X}$, from X-ray torus modeling of NuSTAR data. Our sample consists of 10 local CT AGN where both of these estimates are available. We test for systematic differences in $\kappa_{Bol}$ values produced when using two widely used IR torus models and two widely used X-ray torus models, finding consistency within the uncertainties. We find that the mean $\kappa_{Bol}$ of our sample in the range $L_{Bol}\approx10^{42}-10^{45}$ erg/s is log$_{10}\kappa_{Bol}=1.44\pm0.12$ with an intrinsic scatter of $\sim0.2$ dex, and that our derived $\kappa_{Bol}$ values are consistent with previously established relationships between $\kappa_{Bol}$ and $L_{Bol}$ and $\kappa_{Bol}$ and Eddington ratio. We investigate if $\kappa_{Bol}$ is dependent on $N_H$ by comparing our results on CT AGN to published results on less-obscured AGN, finding no significant dependence. Since many of our sample are megamaser AGN, known to be viewed edge-on, and furthermore under the assumptions of AGN unification whereby unobscured AGN are viewed face-on, our result implies that the X-ray emitting corona is not strongly anisotropic. Finally, we present $\kappa_{Bol}$ values for CT AGN identified in X-ray surveys as a function of their observed $L_X$, where an estimate of their intrinsic $L_{X}$ is not available, and redshift, useful for estimating the bolometric output of the most obscured AGN across cosmic time.Comment: Accepted for publication in Ap

Endometriosis in the time of internet: how web navigation affects women with endometriosis

Objectives: Patients often search for health-related information on the internet allthough this trend may have some benefits, it also has some risks, such as misinformation. The aim of this study is to evaluate how Internet information seeking affect the level of anxiety in patients with endometriosis. Materials and methods: This prospective observational study was conducted at our outpatient clinic between March 2019 and December 2020. We enrolled We enrolled all patients with a confirmed sonographic diagnosis of endometriosis who had sought information about the disease prior to our visit. We divided them into two groups based on the source of information (Internet only vs multiple sources). Before the visit, we asked women to fill-in validated questionnaires about anxiety, such as the Generalized Anxiety Disorder-7 (GAD) and the Spielberg State Trait Anxiety Inventory (STAI- Y6) and the Endometriosis Health Profile (EHP) − 5. After the visit, the STAI-Y6 was resubmitted to each woman. Results: We enrolled 200 women who filled-in the questionnaires: 46 reported the Internet as the only source of information, 52 sought information also from medically qualified sources, 74 consulted only healthcare professionals, and 28 resorted to medical journals. Women who used the Internet as their exclusive source of information were younger on average and their STAI-Y6 score after the visit was significantly lower compared to other group (34.1 ± 11.5 vs 42.1 ± 14.7, p =.001). Moreover, the difference between the STAI-Y6 scores before and after our assessment was higher in these women (-18.3 ± 14.7 vs −10.3 ± 16.5, p =.003). Conclusions: Women who sought information online were younger, had lower levels of state trait anxiety after our medical evaluation, and a had a greater reduction in anxiety levels after our examination compared to women who consulted other sources to learn more about endometriosis.KEY MESSAGES Women using only Internet are younger than those who use other sources of information. Women who researched symptoms online showed higher pre-examination anxiety levels. Patients with severe pain symptoms consulted both the internet and professionals

Introducing SWERTO: A regional space weather service

The Space WEeatherR TOr vergata university (SWERTO) service is an operational Space Weather service based on data from space-based and ground-based instruments, located in the Physics Department of the University of Rome Tor Vergata, Italy (UNITOV). The service is designed to promote the access to technical and scientific information by the regional industries whose technologies are sensible to Space Weather effects and allows registered users to access scientific data from instrumentation available to UNITOV researchers through national and international collaborations. To non-registered users, it provides a quick-look interface (spaceweather.roma2.infn.it) for the selection and visualization of such data and the visualization of the forecast for flare probability and Solar Energetic Particles (SEP) fluxes from prototype codes. The SWERTO database contains data on particles fluxes from the space missions ALTEA and PAMELA, and high-resolution and full disk spectro-polarimetric solar data. The solar data are related to solar Active Regions (ARs), observed at high resolution with the IBIS (Interferometric BIdimensional Spectropolarimeter) instrument, and full disk Line-of-Sight Doppler and magnetic field at different heights in the solar atmosphere, observed with the MOTH II telescope. SWERTO main goals are: i) design and realize a data-base with the particle fluxes recorded by the space missions and with the spectropolarimetric measurement of the solar photosphere; ii) allow an Open Access to the data-base and to prototype forecast to regional industries involved and exposed to Space Weather effects; iii) implement a tutorial and a FAQ section to help decision makers to realize and evaluate the risks from Space Weather events; iv) outreach and customer products