A5024609506- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Nuclear physics research studies
- Galaxies: Formation, Evolution, Phenomena
- Astrophysical Phenomena and Observations
- Medical Imaging Techniques and Applications
- Nuclear Physics and Applications
- Astrophysics and Star Formation Studies
- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Cosmic Phenomena
- Dark Matter and Cosmic Phenomena
- Atomic and Molecular Physics
- Advanced Radiotherapy Techniques
- Astronomical and nuclear sciences
- Atomic and Subatomic Physics Research
- Gamma-ray bursts and supernovae
- Neutrino Physics Research
- Radioactive Decay and Measurement Techniques
- Radiation Detection and Scintillator Technologies
- Radiopharmaceutical Chemistry and Applications
- Advanced X-ray and CT Imaging
- Particle Detector Development and Performance
- Radiation Therapy and Dosimetry
Washington University in St. Louis
2025
National Physical Laboratory
2017-2024
Kingston Health Sciences Centre
2024
Ministry of Defence
2023-2024
Royal Free London NHS Foundation Trust
2024
The University of Melbourne
2010-2024
Queen's University
2024
Lewisham and Greenwich NHS Trust
2023-2024
Scripps (United States)
2024
Scripps Institution of Oceanography
2024
We consider the effect of radiation pressure from ionizing photons on black hole (BH) mass estimates based application virial theorem to broad emission lines in AGN spectra. BH masses only product Δ V2R and neglecting can be severely underestimated, especially objects close Eddington limit. provide an empirical calibration correction for pressure, we show that it is consistent with a simple physical model which BLR clouds are optically thick have average column densities NH ∼ 1023 cm −2....
Coulomb-excitation experiments to study electromagnetic properties of radioactive even-even Hg isotopes were performed with $2.85\text{ }\mathrm{MeV}/\mathrm{nucleon}\text{ }\mathrm{mercury}$ beams from REX-ISOLDE. Magnitudes and relative signs the reduced $E2$ matrix elements that couple ground state low-lying excited states in $^{182\ensuremath{-}188}\mathrm{Hg}$ extracted. Information on deformation first ${0}^{+}$ was deduced using quadrupole sum rules approach. Results show is slightly...
The projected performance and detector configuration of nEXO are described in this pre-Conceptual Design Report (pCDR). is a tonne-scale neutrinoless double beta ($0νββ$) decay search $^{136}$Xe, based on the ultra-low background liquid xenon technology validated by EXO-200. With $\simeq$ 5000 kg enriched to 90% isotope 136, has half-life sensitivity approximately $10^{28}$ years. This represents an improvement about two orders magnitude with respect current results. Based experience gained...
We have identified 12 Seyfert 1 galaxies that exhibit optical polarization spectra similar to those of 2 in which polarized broad-lines are detected. present new spectropolarimetric observations 3 them: Was 45, Mrk 231 and NGC 3227. These objects appear be as a result far-field scattering the polar illumination cones circum-nuclear torus. estimate they represent between 10 30 per cent population; found amongst all main spectroscopic sub-types, including narrow-line galaxies. shown elsewhere...
We are conducting a large observing program with the Spitzer Space Telescope to determine mid- far-IR spectral energy distributions of well-defined sample 87 nearby, 12 μm-selected Seyfert galaxies. In this paper we present results IRS low-resolution spectroscopy statistically representative subsample 51 galaxies (59%), an analysis continuum shapes and comparison types. find that spectra clearly divide into groups based on their features. The largest group (47% 51) shows very red suggestive...
We have used GMOS-IFU and high-resolution HST-ACS observations to map, in unprecedented detail, the gas velocity field structure within 0.7 kpc circumnuclear ring of SBb LINER/Seyfert 1 galaxy NGC 1097. find clear evidence radial streaming motions associated with spiral structures leading unresolved (<3.5 pc) nucleus, which we interpret as part fueling chain by is transported nuclear starburst supermassive black hole.
Several studies indicate that radio-loud (RL) Active Galactic Nuclei (AGN) are produced only by the most massive black holes (BH), $M_{\rm BH} \sim 10^8$-$10^{10} M_\odot$. This idea has been challenged discovery of RL Narrow Line Seyfert 1 (RL NLSy1), having estimated masses BH}$$\sim$$10^6$-$10^7$ M$_\odot$. However, these low BH}$ estimates might be due to projection effects. Spectropolarimetry allows us test this possibility looking at NLSy1s under a different perspective, i.e., from...
Radiopharmaceutical dosimetry depends on the localization in space and time of radioactive sources requires estimation amount energy emitted by deposited within targets. In particular, when computing resources are not accessible, this task can be performed using precomputed tables specific absorbed fractions (SAFs) or S values based dosimetric models. The aim OpenDose collaboration is to generate make freely available a range data tools. <b>Methods:</b> brings together expertise from 18...
Abstract Purpose Patient-specific dosimetry is required to ensure the safety of molecular radiotherapy and predict response. Dosimetry involves several steps, first which determination activity radiopharmaceutical taken up by an organ/lesion over time. As uncertainties propagate along each subsequent steps (integration time–activity curve, absorbed dose calculation), establishing a reliable quantification essential. The MRTDosimetry project was European initiative bring together expertise in...
Extensive regions of ionized gas are found at large distances from the centres many radio galaxies which exhibit nuclear emission lines. We use line ratio diagnostic diagrams to show that emission-line spectra extended nebulosities form well-defined trends with excitation (as measured by [O I]/[O III] ratio). Remarkably, associated narrow lie along same loci. Such can be explained as a variation in ionization parameter for photoionization continuum spectrum which, small scatter diagrams,...
We report the discovery of gas streaming motions along nuclear spiral arms toward LINER nucleus galaxy NGC 6951. The observations, obtained using GMOS integral field spectrograph on Gemini North telescope, yielded maps flux distributions and kinematics in Hα, [N II] λ6584, [S λλ6717, 6731 emission lines inner 7'' × 15'' galaxy. This region includes a circumnuclear star-forming ring with radius ~500 pc, inside ring, nucleus. ionized is dominated by rotation, but subtraction kinematic model...
The \ensuremath{\alpha} decay of the neutron-deficient nuclide $^{105}\mathrm{Te}$ was observed. $^{50}\mathrm{Cr}$($^{58}\mathrm{Ni}$,$3n$) reaction used to produce nuclei. residues were selected with Argonne Fragment Mass Analyzer and implanted into a double-sided Si strip detector where their subsequent detected. An \ensuremath{\alpha}-decay $Q$ value ${Q}_{\ensuremath{\alpha}}=4900(50)$ keV half life ${T}_{1/2}=0.70(\ensuremath{-}0.17+0.25)\ensuremath{\mu}$s measured for reduced width...
This review evaluates the current literature on recent advances of preoperative planning in management complex proximal humerus fractures (PHF). PHFs can pose a considerable challenge for orthopaedic surgeons due to their diversity presentation and complexity. Poor lead prolonged operations, increased blood loss, higher risk complications, stress surgical team. Recent have seen evolution from conventional methods computer-assisted virtual technology (CAVST) three-dimensional (3D) printing,...
The purpose of this study was to pilot test a patient-reported social risk factor (SRF) screening tool among rheumatology outpatients and examine the distribution SRFs in population. A SRF completed electronically by patients. Patients were screened for four core domains (financial strain, housing instability, food insecurity, transportation needs) supplemental (physical inactivity, isolation, stress, depression). Data from electronic health record extracted patients with at least one domain...
We have obtained Hubble Space Telescope Faint Object Camera (FOC) f/48 long-slit spectroscopy of the inner 4'' narrow-line region (NLR) NGC 1068 between 3500 and 5400 Å with a spectral resolution 1.78 pixel-1. At spatial scale 00287 pixel-1 these data provide an order-of-magnitude improvement in over previous ground-based spectra allow us to trace interaction radio jet gas NLR. Our results show that within ±05 emission lines are kinematically disturbed split into two components whose...
We present new observations, including both narrow-band imaging and long-slit spectroscopy, of the optical filaments in Centaurus A. The line-emitting which compose part well-known 'optical jet' are complex highly structured at limit ground-based resolution. Variations surface brightness, line intensity ratios velocity field occur on spatial scales ~ 100 pc. find no evidence [O III] λ5007 emission associated with either 'inner or a possible 'counter jet'. spectra very similar character to...
The first data on the relative single-particle energies outside doubly magic (100)Sn nucleus were obtained. A prompt 171.7(6) keV gamma-ray transition was correlated with protons emitted following beta decay of (101)Sn and is interpreted as between single-neutron g(7/2) d(5/2) orbitals in (101)Sn. This observation provides a stringent test current nuclear structure models. measured nug(7/2)-nud(5/2) energy splitting compared values calculated using mean-field potentials used to calculate...
We present two-dimensional gaseous kinematics of the inner 1.1 x 1.6kpc^2 Seyfert 2 galaxy NGC2110, from optical spectra obtained with GMOS integral field spectrograph on Gemini South telescope at a spatial resolution 100pc. Gas emission is observed over whole field-of-view, complex - and frequently double emission-line profiles. have identified four components in emitting gas, according to their velocity dispersion (sigma), which we refer as: (1) warm gas disk (sigma = 100-220km/s); (2)...
Alpha decays in the EXO-200 detector are used to measure fraction of charged $^{218}\text{Po}$ and $^{214}\text{Bi}$ daughters created from $\ensuremath{\alpha}$ $\ensuremath{\beta}$ decays, respectively. $^{222}\text{Rn} \ensuremath{\alpha}$ liquid xenon (LXe) found produce $^{218}\text{Po}^{+}$ ions $50.3\ifmmode\pm\else\textpm\fi{}3.0%$ time, while remainder atoms neutral. The $^{214}\text{Bi}^{+}$ $^{214}\text{Pb} \ensuremath{\beta}$ LXe is be $76.4\ifmmode\pm\else\textpm\fi{}5.7%$,...
Patient-specific absorbed dose calculations for molecular radiotherapy require accurate activity quantification. This is commonly derived from Single-Photon Emission Computed Tomography (SPECT) imaging using a calibration factor relating detected counts to known in phantom insert.A series of inserts, based on the mathematical models underlying many clinical dosimetry calculations, have been produced 3D printing techniques. SPECT/CT data inserts has used calculate new organ-specific factors...
We present an analysis of historical multi-wavelength emission the Changing Look (CL) Active Galactic Nucleus (AGN) in NGC 2992, covering epochs ranging from 1978 to 2021, as well new X-ray and optical spectra. The galaxy presents multiple Seyfert type transitions 2 intermediate-type, losing regaining its H$α$ BEL recurrently. In X-rays, source shows intrinsic variability with absorption corrected luminosity varying by a factor $\sim$ 40. rule out tidal disruption events or variable...
We present optical spectropolarimetry confirming Vermeulen et al.' recent discovery of a broad Ha emission line in BL Lacertae. This feature, which is at about the same strength spectra taken two days apart, comparable width (FWHM ≈ 4000 km s−1) and luminosity (LHα ∼ 1041 erg to Hα lines Seyfert type 1 galaxies. also identify narrow [N ii] λ6583, [O i] λ6300 [Fe vii] λ6087. The continuum polarization was relatively low level ( 5 per cent) with no significant wavelength dependence. estimate...
The application of the virial theorem to Broad Line Region Active Galactic Nuclei allows Black Hole mass estimates for large samples objects at all redshifts. In a recent paper we showed that ionizing radiation pressure onto BLR clouds affects BH and provided empirically calibrated corrections. More recently, new test importance forces has been proposed: MBH-sigma relation used estimate MBH sample type-2 AGN relations (with without pressure) type-1 extracted from same parent population....