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1.	Algaba, Juan-Carlos, et al. (author) Broadband Multi-wavelength Properties of M87 during the 2017 Event Horizon Telescope Campaign 2021 In: Astrophysical Journal Letters. - : American Astronomical Society. - 2041-8213 .- 2041-8205. ; 911:1 Research review (peer-reviewed)abstract In 2017, the Event Horizon Telescope (EHT) Collaboration succeeded in capturing the first direct image of the center of the M87 galaxy. The asymmetric ring morphology and size are consistent with theoretical expectations for a weakly accreting supermassive black hole of mass ∼6.5 × 109 M o˙. The EHTC also partnered with several international facilities in space and on the ground, to arrange an extensive, quasi-simultaneous multi-wavelength campaign. This Letter presents the results and analysis of this campaign, as well as the multi-wavelength data as a legacy data repository. We captured M87 in a historically low state, and the core flux dominates over HST-1 at high energies, making it possible to combine core flux constraints with the more spatially precise very long baseline interferometry data. We present the most complete simultaneous multi-wavelength spectrum of the active nucleus to date, and discuss the complexity and caveats of combining data from different spatial scales into one broadband spectrum. We apply two heuristic, isotropic leptonic single-zone models to provide insight into the basic source properties, but conclude that a structured jet is necessary to explain M87's spectrum. We can exclude that the simultaneous γ-ray emission is produced via inverse Compton emission in the same region producing the EHT mm-band emission, and further conclude that the γ-rays can only be produced in the inner jets (inward of HST-1) if there are strongly particle-dominated regions. Direct synchrotron emission from accelerated protons and secondaries cannot yet be excluded.
2.	Abbasi, R., et al. (author) Acceptance Tests of more than 10 000 Photomultiplier Tubes for the multi-PMT Digital Optical Modules of the IceCube Upgrade 2024 In: Journal of Instrumentation. - 1748-0221. ; 19:7 Journal article (peer-reviewed)abstract More than 10 000 photomultiplier tubes (PMTs) with a diameter of 80 mm will be installed in multi-PMT Digital Optical Modules (mDOMs) of the IceCube Upgrade. These have been tested and pre-calibrated at two sites. A throughput of more than 1000 PMTs per week with both sites was achieved with a modular design of the testing facilities and highly automated testing procedures. The testing facilities can easily be adapted to other PMTs, such that they can, e.g., be re-used for testing the PMTs for IceCube-Gen2. Single photoelectron response, high voltage dependence, time resolution, prepulse, late pulse, afterpulse probabilities, and dark rates were measured for each PMT. We describe the design of the testing facilities, the testing procedures, and the results of the acceptance tests.
3.	Abbasi, R., et al. (author) Characterization of the astrophysical diffuse neutrino flux using starting track events in IceCube 2024 In: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2470-0010 .- 2470-0029. ; 110:2 Journal article (peer-reviewed)abstract A measurement of the diffuse astrophysical neutrino spectrum is presented using IceCube data collected from 2011-2022 (10.3 years). We developed novel detection techniques to search for events with a contained vertex and exiting track induced by muon neutrinos undergoing a charged-current interaction. Searching for these starting track events allows us to not only more effectively reject atmospheric muons but also atmospheric neutrino backgrounds in the southern sky, opening a new window to the sub-100 TeV astrophysical neutrino sky. The event selection is constructed using a dynamic starting track veto and machine learning algorithms. We use this data to measure the astrophysical diffuse flux as a single power law flux (SPL) with a best-fit spectral index of γ=2.58-0.09+0.10 and per-flavor normalization of φper-flavorAstro=1.68-0.22+0.19×10-18×GeV-1 cm-2 s-1 sr-1 (at 100 TeV). The sensitive energy range for this dataset is 3-550 TeV under the SPL assumption. This data was also used to measure the flux under a broken power law, however we did not find any evidence of a low energy cutoff.
4.	Abbasi, R., et al. (author) Improved modeling of in-ice particle showers for IceCube event reconstruction 2024 In: Journal of Instrumentation. - 1748-0221. ; 19:6 Journal article (peer-reviewed)abstract The IceCube Neutrino Observatory relies on an array of photomultiplier tubes to detect Cherenkov light produced by charged particles in the South Pole ice. IceCube data analyses depend on an in-depth characterization of the glacial ice, and on novel approaches in event reconstruction that utilize fast approximations of photoelectron yields. Here, a more accurate model is derived for event reconstruction that better captures our current knowledge of ice optical properties. When evaluated on a Monte Carlo simulation set, the median angular resolution for in-ice particle showers improves by over a factor of three compared to a reconstruction based on a simplified model of the ice. The most substantial improvement is obtained when including effects of birefringence due to the polycrystalline structure of the ice. When evaluated on data classified as particle showers in the high-energy starting events sample, a significantly improved description of the events is observed.
5.	Abbasi, R., et al. (author) Citizen science for IceCube: Name that Neutrino 2024 In: European Physical Journal Plus. - 2190-5444. ; 139:6 Journal article (peer-reviewed)abstract Name that Neutrino is a citizen science project where volunteers aid in classification of events for the IceCube Neutrino Observatory, an immense particle detector at the geographic South Pole. From March 2023 to September 2023, volunteers did classifications of videos produced from simulated data of both neutrino signal and background interactions. Name that Neutrino obtained more than 128,000 classifications by over 1800 registered volunteers that were compared to results obtained by a deep neural network machine-learning algorithm. Possible improvements for both Name that Neutrino and the deep neural network are discussed.
6.	Abbasi, R., et al. (author) Search for 10-1000 GeV Neutrinos from Gamma-Ray Bursts with IceCube 2024 In: Astrophysical Journal. - : Institute of Physics (IOP). - 1538-4357 .- 0004-637X. ; 964:2 Journal article (peer-reviewed)abstract We present the results of a search for 10-1000 GeV neutrinos from 2268 gamma-ray bursts (GRBs) over 8 yr of IceCube-DeepCore data. This work probes burst physics below the photosphere where electromagnetic radiation cannot escape. Neutrinos of tens of giga electronvolts are predicted in sub-photospheric collision of free-streaming neutrons with bulk-jet protons. In a first analysis, we searched for the most significant neutrino-GRB coincidence using six overlapping time windows centered on the prompt phase of each GRB. In a second analysis, we conducted a search for a group of GRBs, each individually too weak to be detectable, but potentially significant when combined. No evidence of neutrino emission is found for either analysis. The most significant neutrino coincidence is for Fermi-GBM GRB bn 140807500, with a p-value of 0.097 corrected for all trials. The binomial test used to search for a group of GRBs had a p-value of 0.65 after all trial corrections. The binomial test found a group consisting only of GRB bn 140807500 and no additional GRBs. The neutrino limits of this work complement those obtained by IceCube at tera electronvolt to peta electronvolt energies. We compare our findings for the large set of GRBs as well as GRB 221009A to the sub-photospheric neutron-proton collision model and find that GRB 221009A provides the most constraining limit on baryon loading. For a jet Lorentz factor of 300 (800), the baryon loading on GRB 221009A is lower than 3.85 (2.13) at a 90% confidence level.
7.	Abbasi, R., et al. (author) Measurement of atmospheric neutrino mixing with improved IceCube DeepCore calibration and data processing 2023 In: Physical Review D. - 2470-0010 .- 2470-0029. ; 108:1 Journal article (peer-reviewed)abstract We describe a new data sample of IceCube DeepCore and report on the latest measurement of atmospheric neutrino oscillations obtained with data recorded between 2011-2019. The sample includes significant improvements in data calibration, detector simulation, and data processing, and the analysis benefits from a sophisticated treatment of systematic uncertainties, with significantly greater level of detail since our last study. By measuring the relative fluxes of neutrino flavors as a function of their reconstructed energies and arrival directions we constrain the atmospheric neutrino mixing parameters to be sin2θ23=0.51±0.05 and Δm322=2.41±0.07×10-3 eV2, assuming a normal mass ordering. The errors include both statistical and systematic uncertainties. The resulting 40% reduction in the error of both parameters with respect to our previous result makes this the most precise measurement of oscillation parameters using atmospheric neutrinos. Our results are also compatible and complementary to those obtained using neutrino beams from accelerators, which are obtained at lower neutrino energies and are subject to different sources of uncertainties.
8.	Abbasi, R., et al. (author) Observation of seasonal variations of the flux of high-energy atmospheric neutrinos with IceCube 2023 In: European Physical Journal C. - : Springer. - 1434-6044 .- 1434-6052. ; 83:9 Journal article (peer-reviewed)abstract Atmospheric muon neutrinos are produced by meson decays in cosmic-ray-induced air showers. The flux depends on meteorological quantities such as the air temperature, which affects the density of air. Competition between decay and re-interaction of those mesons in the first particle production generations gives rise to a higher neutrino flux when the air density in the stratosphere is lower, corresponding to a higher temperature. A measurement of a temperature dependence of the atmospheric νμ flux provides a novel method for constraining hadronic interaction models of air showers. It is particularly sensitive to the production of kaons. Studying this temperature dependence for the first time requires a large sample of high-energy neutrinos as well as a detailed understanding of atmospheric properties. We report the significant (>10σ) observation of a correlation between the rate of more than 260,000 neutrinos, detected by IceCube between 2012 and 2018, and atmospheric temperatures of the stratosphere, measured by the Atmospheric Infrared Sounder (AIRS) instrument aboard NASA’s AQUA satellite. For the observed 10 % seasonal change of effective atmospheric temperature we measure a 3.5(3) % change in the muon neutrino flux. This observed correlation deviates by about 2-3 standard deviations from the expected correlation of 4.3 % as obtained from theoretical predictions under the assumption of various hadronic interaction models.
9.	Abbasi, R., et al. (author) Search for Galactic Core-collapse Supernovae in a Decade of Data Taken with the IceCube Neutrino Observatory 2024 In: Astrophysical Journal. - : Institute of Physics Publishing (IOPP). - 1538-4357 .- 0004-637X. ; 961:1 Journal article (peer-reviewed)abstract The IceCube Neutrino Observatory has been continuously taking data to search for O(0.5–10) s long neutrino bursts since 2007. Even if a Galactic core-collapse supernova is optically obscured or collapses to a black hole instead of exploding, it will be detectable via the O(10) MeV neutrino burst emitted during the collapse. We discuss a search for such events covering the time between 2008 April 17 and 2019 December 31. Considering the average data taking and analysis uptime of 91.7% after all selection cuts, this is equivalent to 10.735 yr of continuous data taking. In order to test the most conservative neutrino production scenario, the selection cuts were optimized for a model based on an 8.8 solar mass progenitor collapsing to an O–Ne–Mg core. Conservative assumptions on the effects of neutrino oscillations in the exploding star were made. The final selection cut was set to ensure that the probability to detect such a supernova within the Milky Way exceeds 99%. No such neutrino burst was found in the data after performing a blind analysis. Hence, a 90% C.L. upper limit on the rate of core-collapse supernovae out to distances of ≈25 kpc was determined to be 0.23 yr−1. For the more distant Magellanic Clouds, only high neutrino luminosity supernovae will be detectable by IceCube, unless external information on the burst time is available. We determined a model-independent limit by parameterizing the dependence on the neutrino luminosity and the energy spectrum.
10.	Abbasi, R., et al. (author) IceCat-1: The IceCube Event Catalog of Alert Tracks 2023 In: Astrophysical Journal, Supplement Series. - : IOP Publishing Ltd. - 1538-4365 .- 0067-0049. ; 269:1 Journal article (peer-reviewed)abstract We present a catalog of likely astrophysical neutrino track-like events from the IceCube Neutrino Observatory. IceCube began reporting likely astrophysical neutrinos in 2016, and this system was updated in 2019. The catalog presented here includes events that were reported in real time since 2019, as well as events identified in archival data samples starting from 2011. We report 275 neutrino events from two selection channels as the first entries in the catalog, the IceCube Event Catalog of Alert Tracks, which will see ongoing extensions with additional alerts. The Gold and Bronze alert channels respectively provide neutrino candidates with a 50% and 30% probability of being astrophysical, on average assuming an astrophysical neutrino power-law energy spectral index of 2.19. For each neutrino alert, we provide the reconstructed energy, direction, false-alarm rate, probability of being astrophysical in origin, and likelihood contours describing the spatial uncertainty in the alert's reconstructed location. We also investigate a directional correlation of these neutrino events with gamma-ray and X-ray catalogs, including 4FGL, 3HWC, TeVCat, and Swift-BAT.
11.	Abbasi, R., et al. (author) Search for neutrino lines from dark matter annihilation and decay with IceCube 2023 In: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 108:10 Journal article (peer-reviewed)abstract Dark matter particles in the Galactic Center and halo can annihilate or decay into a pair of neutrinos producing a monochromatic flux of neutrinos. The spectral feature of this signal is unique and it is not expected from any astrophysical production mechanism. Its observation would constitute a dark matter smoking gun signal. We performed the first dedicated search with a neutrino telescope for such signal, by looking at both the angular and energy information of the neutrino events. To this end, a total of five years of IceCube's DeepCore data has been used to test dark matter masses ranging from 10 GeV to 40 TeV. No significant neutrino excess was found and upper limits on the annihilation cross section, as well as lower limits on the dark matter lifetime, were set. The limits reached are of the order of 10-24 cm3/s for an annihilation and up to 1027 s for decaying dark matter. Using the same data sample we also derive limits for dark matter annihilation or decay into a pair of Standard Model charged particles.
12.	Palmer, Nicholette D, et al. (author) A genome-wide association search for type 2 diabetes genes in African Americans. 2012 In: PloS one. - San Francisco : Public Library of Science (PLoS). - 1932-6203. ; 7:1, s. e29202- Journal article (peer-reviewed)abstract African Americans are disproportionately affected by type 2 diabetes (T2DM) yet few studies have examined T2DM using genome-wide association approaches in this ethnicity. The aim of this study was to identify genes associated with T2DM in the African American population. We performed a Genome Wide Association Study (GWAS) using the Affymetrix 6.0 array in 965 African-American cases with T2DM and end-stage renal disease (T2DM-ESRD) and 1029 population-based controls. The most significant SNPs (n = 550 independent loci) were genotyped in a replication cohort and 122 SNPs (n = 98 independent loci) were further tested through genotyping three additional validation cohorts followed by meta-analysis in all five cohorts totaling 3,132 cases and 3,317 controls. Twelve SNPs had evidence of association in the GWAS (P<0.0071), were directionally consistent in the Replication cohort and were associated with T2DM in subjects without nephropathy (P<0.05). Meta-analysis in all cases and controls revealed a single SNP reaching genome-wide significance (P<2.5×10(-8)). SNP rs7560163 (P = 7.0×10(-9), OR (95% CI) = 0.75 (0.67-0.84)) is located intergenically between RND3 and RBM43. Four additional loci (rs7542900, rs4659485, rs2722769 and rs7107217) were associated with T2DM (P<0.05) and reached more nominal levels of significance (P<2.5×10(-5)) in the overall analysis and may represent novel loci that contribute to T2DM. We have identified novel T2DM-susceptibility variants in the African-American population. Notably, T2DM risk was associated with the major allele and implies an interesting genetic architecture in this population. These results suggest that multiple loci underlie T2DM susceptibility in the African-American population and that these loci are distinct from those identified in other ethnic populations.
13.	Abramowski, A., et al. (author) Discovery of variable VHE gamma-ray emission from the binary system 1FGL J1018.6-5856 2015 In: Astronomy and Astrophysics Supplement Series. - : EDP Sciences. - 0365-0138 .- 1286-4846. ; 577 Journal article (peer-reviewed)abstract Re-observations with the HESS telescope array of the very high-energy (VHE) source HESS J1018-589 A that is coincident with the Fermi-LAT γ-ray binary 1FGL J1018.6-5856 have resulted in a source detection significance of more than 9σ and the detection of variability (χ$^2$/ν of 238.3/155) in the emitted γ-ray flux. This variability confirms the association of HESS J1018-589 A with the high-energy γ-ray binary detected by Fermi-LAT and also confirms the point-like source as a new VHE binary system. The spectrum of HESS J1018-589 A is best fit with a power-law function with photon index Γ = 2.20 \plusmn 0.14$_stat$ \plusmn 0.2$_sys$. Emission is detected up to ~20 TeV. The mean differential flux level is (2.9 \plusmn 0.4) \times 10$^-13$ TeV$^-1$ cm$^-2$ s$^-1$ at 1 TeV, equivalent to ~1% of the flux from the Crab Nebula at the same energy. Variability is clearly detected in the night-by-night light curve. When folded on the orbital period of 16.58 days, the rebinned light curve peaks in phase with the observed X-ray and high-energy phaseograms. The fit of the HESS phaseogram to a constant flux provides evidence of periodicity at the level of N$_sigma$\gt 3σ. The shape of the VHE phaseogram and measured spectrum suggest a low-inclination, low-eccentricity system with amodest impact from VHE γ-ray absorption due to pair production (τ \lsim 1 at 300 GeV).
14.	Locke, Adam E, et al. (author) Genetic studies of body mass index yield new insights for obesity biology. 2015 In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 518:7538, s. 197-401 Journal article (peer-reviewed)abstract Obesity is heritable and predisposes to many diseases. To understand the genetic basis of obesity better, here we conduct a genome-wide association study and Metabochip meta-analysis of body mass index (BMI), a measure commonly used to define obesity and assess adiposity, in up to 339,224 individuals. This analysis identifies 97 BMI-associated loci (P < 5 × 10(-8)), 56 of which are novel. Five loci demonstrate clear evidence of several independent association signals, and many loci have significant effects on other metabolic phenotypes. The 97 loci account for ∼2.7% of BMI variation, and genome-wide estimates suggest that common variation accounts for >20% of BMI variation. Pathway analyses provide strong support for a role of the central nervous system in obesity susceptibility and implicate new genes and pathways, including those related to synaptic function, glutamate signalling, insulin secretion/action, energy metabolism, lipid biology and adipogenesis.
15.	Shungin, Dmitry, et al. (author) New genetic loci link adipose and insulin biology to body fat distribution. 2015 In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 518:7538, s. 187-378 Journal article (peer-reviewed)abstract Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms.
16.	Abbasi, R., et al. (author) A Search for Coincident Neutrino Emission from Fast Radio Bursts with Seven Years of IceCube Cascade Events 2023 In: Astrophysical Journal. - : Institute of Physics (IOP). - 1538-4357 .- 0004-637X. ; 946:2 Journal article (peer-reviewed)abstract This paper presents the results of a search for neutrinos that are spatially and temporally coincident with 22 unique, nonrepeating fast radio bursts (FRBs) and one repeating FRB (FRB 121102). FRBs are a rapidly growing class of Galactic and extragalactic astrophysical objects that are considered a potential source of high-energy neutrinos. The IceCube Neutrino Observatory's previous FRB analyses have solely used track events. This search utilizes seven years of IceCube cascade events which are statistically independent of track events. This event selection allows probing of a longer range of extended timescales due to the low background rate. No statistically significant clustering of neutrinos was observed. Upper limits are set on the time-integrated neutrino flux emitted by FRBs for a range of extended time windows.
17.	Aliu, E., et al. (author) Discovery of High-energy and Very High Energy γ-Ray Emission from the Blazar RBS 0413 2012 In: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 750:2 Journal article (peer-reviewed)abstract We report on the discovery of high-energy (HE; E > 0.1 GeV) and very high energy (VHE; E > 100 GeV) γ-ray emission from the high-frequency-peaked BL Lac object RBS 0413. VERITAS, a ground-based γ-ray observatory, detected VHE γ rays from RBS 0413 with a statistical significance of 5.5 standard deviations (σ) and a γ-ray flux of (1.5 ± 0.6stat ± 0.7syst) × 10–8 photons m–2 s–1 (~1% of the Crab Nebula flux) above 250 GeV. The observed spectrum can be described by a power law with a photon index of 3.18 ± 0.68stat ± 0.30syst. Contemporaneous observations with the Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope detected HE γ rays from RBS 0413 with a statistical significance of more than 9σ, a power-law photon index of 1.57 ± 0.12stat +0.11 – 0.12sys, and a γ-ray flux between 300 MeV and 300 GeV of (1.64 ± 0.43stat +0.31 – 0.22sys) × 10–5photons m–2 s–1. We present the results from Fermi-LAT and VERITAS, including a spectral energy distribution modeling of the γ-ray, quasi-simultaneous X-ray (Swift-XRT), ultraviolet (Swift-UVOT), and R-band optical (MDM) data. We find that, if conditions close to equipartition are required, both the combined synchrotron self-Compton/external-Compton and the lepto-hadronic models are preferred over a pure synchrotron self-Compton model.
18.	Archambault, S., et al. (author) Discovery of a New TeV Gamma-Ray Source : VER J0521+211 2013 In: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 776:2 Journal article (peer-reviewed)abstract We report the detection of a new TeV gamma-ray source, VER J0521+211, based on observations made with the VERITAS imaging atmospheric Cherenkov Telescope Array. These observations were motivated by the discovery of a cluster of >30 GeV photons in the first year of Fermi Large Area Telescope observations. VER J0521+211 is relatively bright at TeV energies, with a mean photon flux of (1.93 ± 0.13stat ± 0.78sys) × 10–11 cm–2 s–1 above 0.2 TeV during the period of the VERITAS observations. The source is strongly variable on a daily timescale across all wavebands, from optical to TeV, with a peak flux corresponding to ~0.3 times the steady Crab Nebula flux at TeV energies. Follow-up observations in the optical and X-ray bands classify the newly discovered TeV source as a BL Lac-type blazar with uncertain redshift, although recent measurements suggest z = 0.108. VER J0521+211 exhibits all the defining properties of blazars in radio, optical, X-ray, and gamma-ray wavelengths.
19.	Aliu, E., et al. (author) VERITAS Observations of the Unusual Extragalactic Transient Swift J164449.3+573451 2011 In: Astrophysical Journal Letters. - 2041-8205 .- 2041-8213. ; 738:2 Journal article (peer-reviewed)abstract We report on very high energy (>100 GeV) gamma-ray observations of Swift J164449.3+573451, an unusual transient object first detected by the Swift Observatory and later detected by multiple radio, optical, and X-ray observatories. A total exposure of 28 hr was obtained on Swift J164449.3+573451 with the Very Energetic Radiation Imaging Telescope Array System (VERITAS) during 2011 March 28-April 15. We do not detect the source and place a differential upper limit on the emission at 500 GeV during these observations of 1.4 × 10–12 erg cm–2 s–1 (99% confidence level). We also present time-resolved upper limits and use a flux limit averaged over the X-ray flaring period to constrain various emission scenarios that can accommodate both the radio-through-X-ray emission detected from the source and the lack of detection by VERITAS.
20.	Simoes, MP, et al. (author) Epidemiological and clinical insights into the enterovirus D68 upsurge in Europe 2021/22 and the emergence of novel B3-derived lineages, ENPEN multicentre study 2024 In: The Journal of infectious diseases. - 1537-6613. Journal article (peer-reviewed)
21.	Aliu, E., et al. (author) Long Term Observations of B2 1215+30 with VERITAS 2013 In: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 779:2 Journal article (peer-reviewed)abstract We report on VERITAS observations of the BL Lac object B2 1215+30 between 2008 and 2012. During this period, the source was detected at very high energies (VHEs; E > 100 GeV) by VERITAS with a significance of 8.9s and showed clear variability on timescales larger than months. In 2011, the source was found to be in a relatively bright state and a power-law fit to the differential photon spectrum yields a spectral index of 3.6 +/- 0.4(stat) +/- 0.3(syst) withan integral flux above 200 GeV of (8.0 +/- 0.9(stat) +/- 3.2(syst)) x 10(-12) cm(-2) s(-1). No short term variability could be detected during the bright state in 2011. Multi-wavelength data were obtained contemporaneously with the VERITAS observations in 2011 and cover optical (Super-LOTIS, MDM, Swift/UVOT), X-ray (Swift/XRT), and gamma-ray (Fermi-LAT) frequencies. These were used to construct the spectral energy distribution (SED) of B2 1215+30. A one-zone leptonic model is used to model the blazar emission and the results are compared to those of MAGIC from early 2011 and other VERITAS-detected blazars. The SED can be reproduced well with model parameters typical for VHE-detected BL Lac objects.
22.	Aliu, E., et al. (author) Multiwavelength Observations of the Previously Unidentified Blazar RX J0648.7+1516 2011 In: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 742:2 Journal article (peer-reviewed)abstract We report on the VERITAS discovery of very high energy (VHE) gamma-ray emission above 200 GeV from the high-frequency-peaked BL Lac (HBL) object RX J0648.7+1516 (GB J0648+1516), associated with 1FGL J0648.8+1516. The photon spectrum above 200 GeV is fitted by a power law dN/dE = F 0(E/E 0)–Γ with a photon index Γ of 4.4 ± 0.8stat ± 0.3syst and a flux normalization F 0 of (2.3 ± 0.5stat ± 1.2sys) × 10–11 TeV–1 cm–2 s–1 with E 0 = 300 GeV. No VHE variability is detected during VERITAS observations of RX J0648.7+1516 between 2010 March 4 and April 15. Following the VHE discovery, the optical identification and spectroscopic redshift were obtained using the Shane 3 m Telescope at the Lick Observatory, showing the unidentified object to be a BL Lac type with a redshift of z = 0.179. Broadband multiwavelength observations contemporaneous with the VERITAS exposure period can be used to subclassify the blazar as an HBL object, including data from the MDM observatory, Swift-UVOT, and X-Ray Telescope, and continuous monitoring at photon energies above 1 GeV from the FermiLarge Area Telescope (LAT). We find that in the absence of undetected, high-energy rapid variability, the one-zone synchrotron self-Compton (SSC) model overproduces the high-energy gamma-ray emission measured by the Fermi-LAT over 2.3 years. The spectral energy distribution can be parameterized satisfactorily with an external-Compton or lepto-hadronic model, which have two and six additional free parameters, respectively, compared to the one-zone SSC model.
23.	Saxena, Richa, et al. (author) Genetic variation in GIPR influences the glucose and insulin responses to an oral glucose challenge 2010 In: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 42:2, s. 142-148 Journal article (peer-reviewed)abstract Glucose levels 2 h after an oral glucose challenge are a clinical measure of glucose tolerance used in the diagnosis of type 2 diabetes. We report a meta-analysis of nine genome-wide association studies (n = 15,234 nondiabetic individuals) and a follow-up of 29 independent loci (n = 6,958–30,620). We identify variants at the GIPR locus associated with 2-h glucose level (rs10423928, β (s.e.m.) = 0.09 (0.01) mmol/l per A allele, P = 2.0 × 10−15). The GIPR A-allele carriers also showed decreased insulin secretion (n = 22,492; insulinogenic index, P = 1.0 × 10−17; ratio of insulin to glucose area under the curve, P = 1.3 × 10−16) and diminished incretin effect (n = 804; P = 4.3 × 10−4). We also identified variants at ADCY5 (rs2877716, P = 4.2 × 10−16), VPS13C (rs17271305, P = 4.1 × 10−8), GCKR (rs1260326, P = 7.1 × 10−11) and TCF7L2 (rs7903146, P = 4.2 × 10−10) associated with 2-h glucose. Of the three newly implicated loci (GIPR, ADCY5 and VPS13C), only ADCY5 was found to be associated with type 2 diabetes in collaborating studies (n = 35,869 cases, 89,798 controls, OR = 1.12, 95% CI 1.09–1.15, P = 4.8 × 10−18).
24.	Aliu, E., et al. (author) Multiwavelength Observations and Modeling of 1ES 1959+650 in a Low Flux State 2013 In: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 775:1 Journal article (peer-reviewed)abstract We report on the VERITAS observations of the high-frequency peaked BL Lac object 1ES 1959+650 in the period 2007-2011. This source is detected at TeV energies by VERITAS at 16.4 standard deviation (σ) significance in 7.6 hr of observation in a low flux state. A multiwavelength spectral energy distribution (SED) is constructed from contemporaneous data from VERITAS,Fermi-LAT, RXTE PCA, and Swift UVOT. Swift XRT data is not included in the SED due to a lack of simultaneous observations with VERITAS. In contrast to the orphan γ-ray flare exhibited by this source in 2002, the X-ray flux of the source is found to vary by an order of magnitude, while other energy regimes exhibit less variable emission. A quasi-equilibrium synchrotron self-Compton model with an additional external radiation field is used to describe three SEDs corresponding to the lowest, highest, and average X-ray states. The variation in the X-ray spectrum is modeled by changing the electron injection spectral index, with minor adjustments of the kinetic luminosity in electrons. This scenario produces small-scale flux variability of the order of 2 in the high energy (E > 1 MeV) and very high energy (E > 100 GeV) γ-ray regimes, which is corroborated by the Fermi-LAT, VERITAS, and Whipple 10 m telescope light curves.
25.	Aliu, E., et al. (author) VERITAS Observations of Six Bright, Hard-spectrum Fermi-LAT Blazars 2012 In: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 759:2 Journal article (peer-reviewed)abstract We report on VERITAS very high energy (VHE; E ≥ 100 GeV) observations of six blazars selected from the Fermi Large Area Telescope First Source Catalog (1FGL). The gamma-ray emission from 1FGL sources was extrapolated up to the VHE band, taking gamma-ray absorption by the extragalactic background light into account. This allowed the selection of six bright, hard-spectrum blazars that were good candidate TeV emitters. Spectroscopic redshift measurements were attempted with the Keck Telescope for the targets without Sloan Digital Sky Survey spectroscopic data. No VHE emission is detected during the observations of the six sources described here. Corresponding TeV upper limits are presented, along with contemporaneousFermi observations and non-concurrent Swift UVOT and X-Ray Telescope data. The blazar broadband spectral energy distributions (SEDs) are assembled and modeled with a single-zone synchrotron self-Compton model. The SED built for each of the six blazars shows a synchrotron peak bordering between the intermediate- and high-spectrum-peak classifications, with four of the six resulting in particle-dominated emission regions.

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