Exceptional Resolution Research Articles

Role of the CMS electromagnetic calorimeter in the measurement of the Higgs boson properties and search for new physics

The precise determination of the mass, the width and the couplings of the particle discovered in 2012 with a mass around 125 GeV is of capital importance to clarify the nature of such a particle, in particular to establish precisely if it is a Standard Model Higgs boson. In several new physics scenarios, in fact, the Higgs boson may behave differently with respect to the Standard Model one, or may not be unique, i.e. there can be more than one Higgs boson. In order to achieve the precision needed to discriminate between different models, the energy resolution, the scale uncertainty and the position resolution for electrons and photons are required to be as good as possible. The CMS scintillating lead-tungstate electromagnetic calorimeter (ECAL) was built as a precise tool with an exceptional energy resolution and a very good position resolution that improved over the years with the knowledge of the detector. Moreover, thanks to the fact that most of the lead-tungstate scintillation light is emitted in about 25 ns, the ECAL can be used to accurately determine the time of flight of photons. We present the current performance of the CMS ECAL, with a special emphasis on the impact on the measurement of the properties of the Higgs boson and on searches for new physics.

Abstract B62: In vivo subcellular resolution optical imaging in the lung reveals early metastastic proliferation, motility and tumor cell - macrophage interaction

Abstract Cancer is the second leading cause of death within the US with 90% of mortality due to metastases. The three major sites of breast cancer metastasis observed clinically are bone (78%), lung (35%) and liver (20%). Of these, the most difficult to access for in vivo, intravital optical imaging is the lung. This is because the lung is a vital organ enclosed within the thoracic cavity and undergoing perpetual motion. Until now, high resolution technologies have traditionally only been able to image fixed, sectioned tissues, or at best, ex vivo whole mount explants. In either case, the cellular dynamics and interactions are lost, and the perfusion of capillaries and oxygenation of cells is altered. By combining a previously published vacuum stabilized imaging window with a custom built two-laser multiphoton microscope specifically designed to optimize resolution and signal to noise, we developed a system capable of imaging the living breathing lung using high resolution multi-photon microscopy. Although these vacuum based window technologies have allowed imaging into the lung, these prior reported systems have focused either on pulmonary dynamics or on the surveillance of the lung by immune cells. The requirements for these studies are different than for imaging cancer growth and motility where subcellular resolution is required to image cell division, organelle content, protrusion and cellular dynamics rather than large fields of view used to capture cells with high velocities. We have attained complete tissue immobilization and exceptional subcellular resolution imaging of experimentally metastasized tumor cells. Using this biological system, we have been able to visualize not only tumor cell proliferation in vivo but also to define when and where tumor cells arrest themselves in the vasculature, and their motility while preparing for extravasation. We observe tumor cells arresting only in capillary vessels and switching from a locomotory – protrusion-high phenotype toward an invasive phenotype whose onset correlates with time of extravasation. We also are able to quantify interaction times between tumor cells and myeloid cells while arrested in the vasculature as well as once they reach the lung parenchyma. We observe that macrophage – tumor cell physical interaction at the extravascular space is extremely long lasting and without apparent effect on tumor cell viability. In vitro, this interaction time can be reduced when macrophages cannot respond to CCL3, molecule that could also control tumor cell – macrophage contact time in vivo. High-resolution imaging of early metastatic events is an extremely useful tool that will allow us not only to follow tumor cell behavior but also to study their interaction with other cell populations, including macrophages. The long-lasting interaction of tumor cells with macrophages, starting soon after tumor cell extravasation, suggests a main role for macrophages during tumor cell seeding in the lungs. Signaling molecules involved in this process can now be studied in details, including CCL3 and its downstream effectors. Citation Format: Carolina A. Rodriguez-Tirado, David Entenberg, Takanori Kitamura, John Condeelis, Jeffrey W. Pollard. In vivo subcellular resolution optical imaging in the lung reveals early metastastic proliferation, motility and tumor cell - macrophage interaction. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Metastasis; 2015 Nov 30-Dec 3; Austin, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(7 Suppl):Abstract nr B62.

Scintillation Properties and Electronic Structures of the Intrinsic and Extrinsic Mixed ElpasolitesCs2NaRBr3I3(R=La, Y)

Scintillators attract wide research interest for their distinct applications in radiation detection. Elpasolite halides are among the most promising scintillators due to their high structural symmetry and good scintillation performance. Better understanding of their underlying scintillation mechanism opens up new possibilities in scintillator development. In this work, we employ a variety of experimental techniques to study the two mixed-anion elpasolites Cs2NaRBr3I3 (R = La, Y). The emission of intrinsic Cs2NaRBr3I3 with a light yield ranging from 20,000 to 40,000 ph/MeV is dominant by self-trapped exciton emission. Partial substitution of R with Ce introduces a competing emission, the Ce3+ 5d to 4f radiative transition. Ab initio calculations were performed to investigate the electronic structures as well as the binding energies of polarons in Cs2NaRBr6. The calculated large self-trapped exciton binding energies are consistent with the observed high light yield due to self-trapped exciton emission. The unique electronic structure of halide elpasolites as calculated enhances the STE stability and the STE emission. The highly tunable scintillation properties of mixed-anion elpasolites underscore the role of their complex scintillation mechanism. Our study provides guidance for the design of new elpasolites scintillators with exceptional energy resolution and light yield desirable for applications.

3D Microstructural Visualization of the Simplest of Eukaryotic Cell (Cyanidioschyzon Merolae) during Mitosis Process using Several New Microscopic Techniques

EM offers exceptional resolution of extremely small biological specimens, providing images of the minutest of organelles and molecules responsible for fundamental cellular phenomena such as division, differentiation and proliferation. The resulting fine structural information will be extraordinary in defining the relationship between cell morphology and cell function. FIB-SEM and 3view-SEM will provide us information of the specimen which will complement the 3D-structural information at whole cell level. We selected C. merolae cell, a primitive unicellular red algae, as an excellent model organism for cell mitotic cycle.Although the size of the cell is 2-5 micron, the body shape (3D-structure) has not well understood yet. Last annual meeting, we described how to analyze 3D- microstructural visualization of an entire cell at a nanoscale resolution using FIB-SEM and 3D reconstruction techniques, Image J and Amira 3D software. Forthermore, by using synchronizing cells to a 6-h light/18-h dark cycle and FIB-SEM, we observed unique architectures of whole C. merolae cells during the mitotic cycle and successfully made 3D-models of individual double-membrane organelles and single-membrane organelles.In this meeting, in addition to analyze the shape and interaction between individual several organelles during mitosis cycle, we aim to reveal individual morphology details and compute the volume occupancy of each organelle. We will discuss you about the relationship between cell body mass and energy efficiency, also. Furthermore, using UHVEM tomography, we also observed the 3D-structure of phycobilisomes, which are essential supramolecular complexes on the surface of the thylakoid membrane in chloroplasts and the micro-compartments (cristae) in mitochondria. Although many reports have provided structural models, we offer the first 3D-structural model of the membrane surface from specimens that were not purified using specific detergents.

Hemodynamic and Light-Scattering Changes of Rat Spinal Cord and Primary Somatosensory Cortex in Response to Innocuous and Noxious Stimuli.

Neuroimaging technologies with an exceptional spatial resolution and noninvasiveness have become a powerful tool for assessing neural activity in both animals and humans. However, the effectiveness of neuroimaging for pain remains unclear partly because the neurovascular coupling during pain processing is not completely characterized. Our current work aims to unravel patterns of neurovascular parameters in pain processing. A novel fiber-optic method was used to acquire absolute values of regional oxy- (HbO) and deoxy-hemoglobin concentrations, oxygen saturation rates (SO2), and the light-scattering coefficients from the spinal cord and primary somatosensory cortex (SI) in 10 rats. Brief mechanical and electrical stimuli (ranging from innocuous to noxious intensities) as well as a long-lasting noxious stimulus (formalin injection) were applied to the hindlimb under pentobarbital anesthesia. Interhemispheric comparisons in the spinal cord and SI were used to confirm functional activation during sensory processing. We found that all neurovascular parameters showed stimulation-induced changes; however, patterns of changes varied with regions and stimuli. Particularly, transient increases in HbO and SO2 were more reliably attributed to brief stimuli, whereas a sustained decrease in SO2 was more reliably attributed to formalin. Only the ipsilateral SI showed delayed responses to brief stimuli. In conclusion, innocuous and noxious stimuli induced significant neurovascular responses at critical centers (e.g., the spinal cord and SI) along the somatosensory pathway; however, there was no single response pattern (as measured by amplitude, duration, lateralization, decrease or increase) that was able to consistently differentiate noxious stimuli. Our results strongly suggested that the neurovascular response patterns differ between brief and long-lasting noxious stimuli, and can also differ between the spinal cord and SI. Therefore, a use of multiple-parameter strategy tailored by stimulus modality (brief or long-lasting) as well as region-dependent characteristics may be more effective in detecting pain using neuroimaging technologies.

Site-Specific Amphiphilic Magnetic Copolymer Nanoaggregates for Dual Imaging

Molecular imaging along with combinations of imaging modalities can provide a thorough understanding of disease, in particular, tumors. Magnetic resonance imaging (MRI) offers exceptional tissue contrast and resolution; whereas optical imaging provides high sensitivity. Hence a norbornene based copolymer (Nor-Cob-Py-Fol) is reported in this paper as a dual-imaging agent. Nor-Cob-Py-Fol having Co2+ complex, pyrene and poly(ethylene glycol) derived folate, have been synthesized using ring-opening metathesis polymerization (ROMP). All the monomers and polymers are characterized by 1H NMR, IR, GPC, and TGA techniques. The morphology of the copolymer nanoaggregates has been evaluated with DLS, TEM, and SEM techniques. The functionalization of Co2+ to the polymer is monitored by FTIR, 1H NMR, and 13C NMR spectroscopy. Furthermore, the presence of Co2+ in the nanoaggregates is confirmed by the EDX (SEM) technique. To prove the MRI capabilities nature of copolymer nanoaggregates, NMR experiment is performed at room temperature. Cell viability studies suggest the biocompatibility nature of the copolymer. Flow cytometry as well as epifluoroscence microscope experiments clearly demonstrate the dual-imaging ability of the newly designed copolymer. The much higher relaxivity ratio (r2/r1) of the present method clearly establishes the superiority of our system as one of the best contrast agents known to the practitioners of magnetic resonance imaging.

Shifts in the eruptive styles at Stromboli in 2010-2014 revealed by ground-based InSAR data.

Ground-Based Interferometric Synthetic Aperture Radar (GBInSAR) is an efficient technique for capturing short, subtle episodes of conduit pressurization in open vent volcanoes like Stromboli (Italy), because it can detect very shallow magma storage, which is difficult to identify using other methods. This technique allows the user to choose the optimal radar location for measuring the most significant deformation signal, provides an exceptional geometrical resolution, and allows for continuous monitoring of the deformation. Here, we present and model ground displacements collected at Stromboli by GBInSAR from January 2010 to August 2014. During this period, the volcano experienced several episodes of intense volcanic activity, culminated in the effusive flank eruption of August 2014. Modelling of the deformation allowed us to estimate a source depth of 482 ± 46 m a.s.l. The cumulative volume change was 4.7 ± 2.6 × 105 m3. The strain energy of the source was evaluated 3–5 times higher than the surface energy needed to open the 6–7 August eruptive fissure. The analysis proposed here can help forecast shifts in the eruptive style and especially the onset of flank eruptions at Stromboli and at similar volcanic systems (e.g. Etna, Piton de La Fournaise, Kilauea).

Resolving Intra- and Inter-Molecular Structure with Non-Contact Atomic Force Microscopy.

A major challenge in molecular investigations at surfaces has been to image individual molecules, and the assemblies they form, with single-bond resolution. Scanning probe microscopy, with its exceptionally high resolution, is ideally suited to this goal. With the introduction of methods exploiting molecularly-terminated tips, where the apex of the probe is, for example, terminated with a single CO, Xe or H2 molecule, scanning probe methods can now achieve higher resolution than ever before. In this review, some of the landmark results related to attaining intramolecular resolution with non-contact atomic force microscopy (NC-AFM) are summarised before focussing on recent reports probing molecular assemblies where apparent intermolecular features have been observed. Several groups have now highlighted the critical role that flexure in the tip-sample junction plays in producing the exceptionally sharp images of both intra- and apparent inter-molecular structure. In the latter case, the features have been identified as imaging artefacts, rather than real intermolecular bonds. This review discusses the potential for NC-AFM to provide exceptional resolution of supramolecular assemblies stabilised via a variety of intermolecular forces and highlights the potential challenges and pitfalls involved in interpreting bonding interactions.

Spatially close azo dyes with sub-nanosecond switching speeds and exceptional temporal resolution.

Photoswitchable bis-azo dyes with an outstanding temporal resolution of 10(15) times between the thermal relaxation rates of their two constituting photochromes are reported. Remarkably, the close spatial proximity of both azo photochromes in these molecular assemblies translates in an unprecedented 10(3) -fold acceleration of the thermal isomerization rate of their faster azo unit compared to the one displayed by the isolated counterpart. Indeed, the relaxation time of the fast-isomerizing platform of the herein reported bis-azobenzenes is as low as 200 ps under ambient conditions. In the wake of these results, the bis-azo dyes described herein are invaluable chromophores for the design of multifunctional light-addressable materials in which simultaneous switching in two very different timescales might be essential.

Highly Sensitive Detection of Surface and Intercalated Impurities in Graphene by LEIS.

Low-energy ion scattering (LEIS) is known for its extreme surface sensitivity, as it yields a quantitative analysis of the outermost surface as well as highly resolved in-depth information for ultrathin surface layers. Hence, it could have been generally considered to be a suitable technique for the analysis of graphene samples. However, due to the low scattering cross section for light elements such as carbon, LEIS has not become a common technique for the characterization of graphene. In the present study we use a high-sensitivity LEIS instrument with parallel energy analysis for the characterization of CVD graphene transferred to thermal silica/silicon substrates. Thanks to its high sensitivity and the exceptional depth resolution typical of LEIS, the graphene layer closure was verified, and different kinds of contaminants were detected, quantified, and localized within the graphene structure. Utilizing the extraordinarily strong neutralization of helium by carbon atoms in graphene, LEIS experiments performed at several primary ion energies permit us to distinguish carbon in graphene from that in nongraphitic forms (e.g., the remains of a resist). Furthermore, metal impurities such as Fe, Sn, and Na located at the graphene-silica interface (intercalated) are detected, and the coverages of Fe and Sn are determined. Hence, high-resolution LEIS is capable of both checking the purity of graphene surfaces and detecting impurities incorporated into graphene layers or their interfaces. Thus, it is a suitable method for monitoring the quality of the whole fabrication process of graphene, including its transfer on various substrates.

Seeing through chaos in multimode fibres

The prediction of light propagation up to hundreds of millimetres within straight or even deformed segments of multimode fibres is demonstrated. The concept is applied in an endoscope and exceptional resolution and footprint are obtained.

SU‐C‐201‐02: Quantitative Small‐Animal SPECT Without Scatter Correction Using High‐Purity Germanium Detectors

Purpose:To evaluate the impact of the exceptional energy resolution of germanium detectors for preclinical SPECT in comparison to conventional detectors.Methods:A cylindrical water phantom was created in GATE with a spherical Tc‐99m source in the center. Sixty‐four projections over 360 degrees using a pinhole collimator were simulated. The same phantom was simulated using air instead of water to establish the true reconstructed voxel intensity without attenuation. Attenuation correction based on the Chang method was performed on MLEM reconstructed images from the water phantom to determine a quantitative measure of the effectiveness of the attenuation correction. Similarly, a NEMA phantom was simulated, and the effectiveness of the attenuation correction was evaluated. Both simulations were carried out using both NaI detectors with an energy resolution of 10% FWHM and Ge detectors with an energy resolution of 1%.Results:Analysis shows that attenuation correction without scatter correction using germanium detectors can reconstruct a small spherical source to within 3.5%. Scatter analysis showed that for standard sized objects in a preclinical scanner, a NaI detector has a scatter‐to‐primary ratio between 7% and 12.5% compared to between 0.8% and 1.5% for a Ge detector. Preliminary results from line profiles through the NEMA phantom suggest that applying attenuation correction without scatter correction provides acceptable results for the Ge detectors but overestimates the phantom activity using NaI detectors. Due to the decreased scatter, we believe that the spillover ratio for the air and water cylinders in the NEMA phantom will be lower using germanium detectors compared to NaI detectors.Conclusion:This work indicates that the superior energy resolution of germanium detectors allows for less scattered photons to be included within the energy window compared to traditional SPECT detectors. This may allow for quantitative SPECT without implementing scatter correction, reducing uncertainties introduced by scatter correction algorithms.Funding provided by NIH/NIBIB grant R01EB013677; Todd Peterson, Ph.D., has had a research contract with PHDs Co., Knoxville, TN

Melanopsin Tristability for Sustained and Broadband Phototransduction

Mammals rely upon three ocular photoreceptors to sense light: rods, cones, and intrinsically photosensitive retinal ganglion cells (ipRGCs). Rods and cones resolve details in the visual scene. Conversely, ipRGCs integrate over time and space, primarily to support "non-image" vision. The integrative mechanisms of ipRGCs are enigmatic, particularly since these cells use a phototransduction motif that allows invertebrates like Drosophila to parse light with exceptional temporal resolution. Here, we provide evidence for a single mechanism that allows ipRGCs to integrate over both time and wavelength. Light distributes the visual pigment, melanopsin, across three states, two silent and one signaling. Photoequilibration among states maintains pigment availability for sustained signaling, stability of the signaling state permits minutes-long temporal summation, and modest spectral separation of the silent states promotes uniform activation across wavelengths. By broadening the tuning of ipRGCs in both temporal and chromatic domains, melanopsin tristability produces signal integration for physiology and behavior.

Probing ultrafast dynamics with attosecond transient absorption

The broad bandwidth of an isolated attosecond pulse excites a vast number of states simultaneously, and the corresponding absorption features can be monitored with exceptional temporal resolution. Novel transient absorption experiments in gases using isolated attosecond pulses are performed in two regimes, one in which the attosecond pulse is overlapped in time with a near-infrared (NIR) pulse and one in which the NIR pulse follows the attosecond pulse. In the latter regime, the attosecond pulse first interacts with a sample, then the observed absorption features are modified by a NIR pulse, which interacts with the sample well after the attosecond pulse has passed. In these experiments, which seem counterintuitive when compared to conventional transient absorption spectroscopy, the weak attosecond pulse induces a polarization of the medium, which is then perturbed by the time-delayed NIR pulse. Recent measurements demonstrate the rich variety of information that can be extracted in this regime.

Nondestructive synchronous beam current monitor.

A fast current transformer is mounted after the deflectors of the Berkeley 88-Inch Cyclotron. The measured signal is amplified and connected to the input of a lock-in amplifier. The lock-in amplifier performs a synchronous detection of the signal at the cyclotron second harmonic frequency. The magnitude of the signal detected is calibrated against a Faraday cup and corresponds to the beam intensity. It has exceptional resolution, long term stability, and can measure the beam current leaving the cyclotron as low as 1 nA.

Tip-Enhanced Raman Scattering of the Local Nanostructure of Epitaxial Graphene Grown on 4H-SiC (0001̅)

Step, ridge, and crack submicro/nanostructures of epitaxial graphene on 4H-SiC (0001̅) were characterized using tip-enhanced Raman scattering (TERS) spectroscopy. The nanostructures were created during graphene synthesis due to a difference in the thermal expansion coefficient of graphene and SiC. These structures are a distinctive property of epitaxial graphene, together with other desirable properties, such as large graphene sheet and minimal defects. The results of this study illustrate that the exceptional spatial resolution of TERS allows spectroscopic measurements of individual nanostructures, a feat which normal Raman spectroscopy is not capable of. By analyzing TERS spectra, the change of local strain on the nanoridge and decreased graphene content in the submicrometer crack were detected. Using G′ band positions in the TERS spectra, the strain difference between the ridge center and flat area was calculated to be 1.6 × 10–3 and 5.8 × 10–4 for uniaxial and biaxial strain, respectively. This confirms the proposed mechanism in previous researches that nanoridges on epitaxial graphene form as a relief against compressive strain. With this study, we demonstrate that TERS is a powerful technique for the characterization of individual local nanostructures on epitaxial graphene.

On the feasibility of measuring urban air pollution by wireless distributed sensor networks

Accurate evaluation of air pollution on human-wellbeing requires high-resolution measurements. Standard air quality monitoring stations provide accurate pollution levels but due to their sparse distribution they cannot capture the highly resolved spatial variations within cities. Similarly, dedicated field campaigns can use tens of measurement devices and obtain highly dense spatial coverage but normally deployment has been limited to short periods of no more than few weeks. Nowadays, advances in communication and sensory technologies enable the deployment of dense grids of wireless distributed air monitoring nodes, yet their sensor ability to capture the spatiotemporal pollutant variability at the sub-neighborhood scale has never been thoroughly tested. This study reports ambient measurements of gaseous air pollutants by a network of six wireless multi-sensor miniature nodes that have been deployed in three urban sites, about 150m apart. We demonstrate the network's capability to capture spatiotemporal concentration variations at an exceptional fine resolution but highlight the need for a frequent in-situ calibration to maintain the consistency of some sensors. Accordingly, a procedure for a field calibration is proposed and shown to improve the system's performance. Overall, our results support the compatibility of wireless distributed sensor networks for measuring urban air pollution at a sub-neighborhood spatial resolution, which suits the requirement for highly spatiotemporal resolved measurements at the breathing-height when assessing exposure to urban air pollution.

Correlative Microscopy Using TEM and SIMS: Parallel Ion Electron Spectrometry (PIES) for High-Resolution, High-Sensitivity Elemental Mapping for Applications in Materials Science and Biology

The capability to simultaneously obtain high spatial resolution and high chemical sensitivity is of paramount importance to gain deeper understanding in physical and biological sciences. The Transmission Electron Microscopy (TEM) offers superior spatial resolution, but, the traditional analytical capabilities associated with electron microscopy such as the Energy Dispersive Spectroscopy (EDS) or Electron Energy-Loss Spectroscopy (EELS) are unfortunately inadequate for characterizing samples containing trace elements (at best 0.1 at. %) or for mapping isotopic distributions [1,2]. On the other hand, Secondary Ion Mass Spectrometry (SIMS) provides extraordinary chemical sensitivity (down to ppm or even ppb) and high dynamic range, but, offers poor lateral resolution [3]. An ex-situ combination of TEM and SIMS in an attempt to overcome the limitations of the techniques taken individually is prone to sample modifications and other artefacts [4]. To overcome the intrinsic instrumental limitations, we have made an in-situ combination to complement the high-sensitivity of SIMS with the exceptional spatial resolution offered by TEM, by developing the correlative TEM-SIMS technique.

Greenland telescope project: Direct confirmation of black hole with sub‐millimeter VLBI

A 12-m diameter radio telescope will be deployed to the Summit Station in Greenland to provide direct confirmation of a Super Massive Black Hole (SMBH) by observing its shadow image in the active galaxy M87. The telescope (Greenland Telescope: GLT) is to become one of the Very Long Baseline Interferometry (VLBI) stations at sub-millimeter (submm) regime, providing the longest baseline > 9,000 km to achieve an exceptional angular resolution of 20 micro arc sec at 350 GHz, which will enable us to resolve the shadow size of ~40 micro arc sec. The triangle with the longest baselines formed by the GLT, the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, and the Submillimeter Array (SMA) in Hawaii will play a key role for the M87 observations. We have been working on the image simulations based on realistic conditions for a better understanding of the possible observed images. In parallel, retrofitting of the telescope and the site developments are in progress. Based on three years of opacity monitoring at 225 GHz, our measurements indicate that the site is excellent for submm observations, comparable to the ALMA site. The GLT is also expected to make single-dish observations up to 1.5 THz.

MO‐G‐17A‐08: Applications of Quantitative PET/CT Imaging of Yttrium‐90: A Tool for Improving Radioembolization

Purpose:Yttrium‐90 (Y90) PET/CT post‐treatment imaging of radioembolization has fostered significant interest from both the interventional radiology and nuclear medicine communities over the past few years. Recent literature has demonstrated high quantitative accuracy of Y90 PET at the activity concentrations common in radioembolization. However, few have explored methods in which this information can be clinically applied toward improving patient care.Methods:IRB approval and informed consent was obtained for over 35 Y90 post‐treatment imaging studies, performed under 2 distinct protocols. In protocol 1, Y90 PET/CT provided quantitative post‐treatment imaging, which was then converted into 3D maps of absorbed‐dose. Both images and absorbed dose maps were used to manage patient care. In protocol 2, tumor absorbed‐dose measurements from Y90 PET/CT were compared to known tumoricidal thresholds. If insufficient absorbed dose was delivered to the tumor, the patient would have an additional Y90 infusion the same day, providing truly patient‐specific Y90 PET/CT based treatment‐planning.Results:Y90 PET/CT allowed for a superior post‐radioembolization evaluation of technical success compared with conventional Y90 bremsstrahlung SPECT. Due to the exceptional resolution of PET, a direct comparison between the distribution of radioembolization and pre‐treatment planning intentions can be made. Further, quantification of tumor absorbed‐dose directly from PET/CT imaging allows for the prediction of treatment efficacy based on a comparison with known tumoricidal thresholds. This immediate evaluation allowed treating physicians to consider additional or alternate therapies before discovering clinical failure weeks later. One protocol 2 patient was found to have a subtumoricidal absorbed dose following radioembolization. This patient received a same‐day infusion of additional Y90 with identical catheter placement to the first infusion. A robust treatment response was seen on follow‐up imaging.Conclusion:Y90 PET/CT produces quantifiable image sets, which can be transformed into 3D maps of absorbed dose. This information can be utilized to improve patient care. SIRTeX Medical, Surefire Medical