The reprocessing features in the X-ray spectrum of the NELG MCG-5-23-16

We present results from the spectral analysis of the Seyfert 1.9 galaxy MCG-5-23-16, based on ASCA, BeppoSAX, Chandra and XMM-Newton observations. The spectrum of this object shows a complex iron Kalpha emission line, which is best modeled by a superposition of a narrow and a broad (possibly relativistic) iron line, together with a Compton reflection component. Comparing results from all (six) available observations, we do not find any significant variation in the flux of both line components. The moderate flux continuum variability (about 25% difference between the brightest and faintest states), however, does not permit us to infer much about the location of the line-emitting material. The amount of Compton reflection is lower than expected from the total iron line EW, implying either an iron overabundance or that one of the two line components (most likely the narrow one) originates in Compton-thin matter.Comment: Accepted for publication in A&

The BeppoSAX X-ray view of reflection-dominated Seyfert Galaxies

We present new results from BeppoSAX observations of reflection-dominated Seyfert galaxies, and namely: 1) the Compton-thick Seyfert 2s NGC1068 and Circinus Galaxy; 2) the Seyfert 1 NGC4051, whose nucleus was observed on May 1998 to have switched off, leaving only a residual reflection component as an echo of its past activity. Our main focus in this paper is on the soft X-ray continuum properties and on the X-ray line spectroscopy.Comment: 6 Latex pages, 5 figures, Accepted for publication in Advances in Space Research, Proceedings of 32nd Sci. Ass. of COSPA

The history of the iron K-alpha line profile in the Piccinotti AGN ESO198-G24

This paper presents ASCA (July 1997), XMM-Newton (December 2000) and BeppoSAX (January 2001) observations of the Piccinotti Seyfert 1 galaxy ESO198-G24. The BeppoSAX 0.1-200 keV spectrum exhibits reprocessing features, probably produced by an X-ray illuminated, relativistic accretion disk subtending a solid angle \~2 pi. During the XMM-Newton observation the fluorescent iron K-alpha line profile (centroid energy E~6.4 keV) was broad and twice as bright as in the BeppoSAX observation. An additional emission feature (E~5.7 keV), detected at the 96.3% confidence level, may be part of a relativistic, double-peaked profile. By contrast, in the earlier ASCA observation the line profile is dominated by a remarkably narrow "core" (intrinsic width <50 eV). If this component is produced by reflection off the inner surface of a molecular torus, its large Equivalent Width (~300 eV) most likely represents the "echo" of a previously brighter flux state, in agreement with the dynamical range covered by the historical X-ray light curve in ESO198-G24.Comment: 9 Latex pages, 11 figures, To appear in Astronomy & Astrophysic

X-ray imaging of the Seyfert 2 galaxy Circinus with Chandra

We present results from the zeroth-order imaging of a Chandra HETGS observation of the nearby Seyfert 2 galaxy Circinus. Twelve X-ray sources were detected in the ACIS-S image of the galaxy, embedded in diffuse X-ray emission. The latter shows a prominent (~18arcsec) soft ``plume'' in the N-W direction, coincident with the [OIII] ionization cone. The radial profiles of the brightest X-ray source at various energies are consistent with an unresolved (FWHM ~0.8arcsec) component, which we identify as the active nucleus, plus two extended components with FWHMs ~ 2.3arcsec and 18arcsec, respectively. In a radius of 3arcsec, the nucleus contributes roughly the same flux as the extended components at the softest energies (< 2 keV). However, at harder energies (> 2 keV), the contribution of the nucleus is dominant. The zeroth-order ACIS spectrum of the nucleus exhibits emission lines at both soft and hard X-rays, including a prominent Fe Kalpha line at 6.4 keV, showing that most of the X-ray lines previously detected with ASCA originate in a compact region (<15 pc). Based on its X-ray spectrum, we argue that the 2.3arcsec extended component is scattered nuclear radiation from nearby ionized gas. The large-scale extended component includes the emission from the N-W plume and possibly from the outer starburst ring.Comment: Figure 1 in color. ApJ Letters, in pres

Development of a Musculoskeletal Ultrasound Education Curriculum for Ultrasound Technologists and Musculoskeletal Fellows: An Adventure in Co-Learning

Musculoskeletal ultrasound is highly operator dependent. Appropriate training is essential to provide high quality imaging to patients. We developed a combined musculoskeletal ultrasound curriculum for our musculoskeletal imaging fellows and our ultrasound technologists to help provide this training. This combined curriculum allows fellows to teach technologists about anatomy and pathology, and the technologists to instruct the fellows on sonographic technique. After viewing our poster exhibit, the learner should: 1.Understand the benefits of co-learning between musculoskeletal imaging fellows and ultrasound technologists 2.Be able to identify key components of a musculoskeletal ultrasound curriculum for both ultrasound technologists and musculoskeletal imaging fellows 3.Understand how we implemented this curriculum in our department through learning sessions. We will review the learning needs of ultrasound technologists as well as those of the musculoskeletal fellows. The curriculum consists of both a didactic component and a hands on component, covering several joints. The learners are given directed readings. During the lecture portion of the curriculum, anatomy, sonographic anatomy, sonographic pathology, and scan technique are reviewed. During the hands on portion of the curriculum, the faculty member first demonstrates the sonographic technique for the particular joint. Next, the faculty facilitates practice scanning between the ultrasound technologists and the musculoskeletal imaging fellows, who work together to provide education to each other based on their skill sets. Methods of assessment will be discussed. We will discuss how we implemented our multiple monthly learning sessions. We will include survey feedback from ultrasound technologists, musculoskeletal imaging fellows, and musculoskeletal imaging faculty. We will discuss implications and future proposals

Compton reflection and iron fluorescence in BeppoSAX observations of Seyfert type 1 galaxies

A sample of nine bright Seyfert 1 and NELG type galaxies, observed with BeppoSAX, is analyzed to assess on a truly broad band basis (0.1-200 keV) the issue of the spectral contributions of Compton reflection and iron line fluorescence from circumnuclear gas. The empirical description adopted for the direct continuum is the commonly used power law with an exponential cut-off. The most direct test of the theoretical predictions, namely that the equivalent width of the line, Walpha, and the strength R of the reflection relative to the direct continuum are closely related to each other, gives a substantially positive result, that is their mean ratio is very close to expectation, and only a modest spread in the iron abundance seems implied. The existence of a steep correlation between R and the slope Gamma of the power law is not confirmed. A weak evidence is found that the existence of a very shallow trend to increase on average with Gamma cannot be altogether excluded in both R and Walpha, but needs to be tested with a larger sample. The energy Ef in the exponential cut-off spans a range from about 80 to more than 300 keV. A possible correlation is found, with Ef increasing on average with Gamma: if ignored, for instance by keeping Ef at a fixed value in a sample study, it could be cause of artificial steepening in a correlation between R and Gamma.Comment: accepted for publication in A&