Search results for "Baseline"
showing 10 items of 299 documents
Apparent superluminal core expansion and limb brightening in the candidate neutrino blazar TXS 0506+056
2019
IceCube has reported a very-high-energy neutrino (IceCube-170922A) in a region containing the blazar TXS 0506+056. Correlated {\gamma}-ray activity has led to the first high-probability association of a high-energy neutrino with an extragalactic source. This blazar has been found to be in a radio outburst during the neutrino event. We have performed target-of-opportunity VLBI imaging observations at 43 GHz frequency with the VLBA two and eight months, respectively, after the neutrino event. We produced two images of TXS 0506+056 with angular resolutions of (0.2x1.1) mas and (0.2x0.5) mas, respectively. The source shows a compact, high brightness temperature core (albeit not approaching the …
Sterile neutrinos and flavor ratios in IceCube
2017
The flavor composition of astrophysical neutrinos observed in neutrino telescopes is a powerful discriminator between different astrophysical neutrino production mechanisms and can also teach us about the particle physics properties of neutrinos. In this paper, we investigate how the possible existence of light sterile neutrinos can affect these flavor ratios. We consider two scenarios: (i) neutrino production in conventional astrophysical sources, followed by partial oscillation into sterile states; (ii) neutrinos from dark matter decay with a primary flavor composition enhanced in tau neutrinos or sterile neutrinos. Throughout the paper, we constrain the sterile neutrino mixing parameters…
Searching for neutrino oscillation parameters in long baseline experiments
2016
Vihonen, Sampsa "Searching for neutrino oscillation parameters in long baseline experiments" in Proceedings, Magellan Workshop: Connecting Neutrino Physics and Astronomy / Dahmke, Stefan K.G., Meyer, Mikko, Vanhoefer, Laura (eds.), Deutsches Elektronen-Synchrotron, DESY : 2016 ; Magellan Workshop, 2016-03-17 - 2016-03-18, Hamburg Magellan Workshop, Hamburg, Germany, 17 Mar 2016 - 18 Mar 2016 ; DESY-PROC 65-70(2016). doi:10.3204/DESY-PROC-2016-05/8
Back to the bases: Building a terrestrial water δ18O baseline for archaeological studies in North Patagonia (Argentina)
2020
Archaeology has been using stable oxygen as an isotopic tracer linked with water consumption for decades, and it has been demonstrated to be a powerful tool to assess paleomobility in bioarchaeology. Central-eastern North Patagonia (Argentina) is an especially appropriate region to apply it since it presents a high density of huntergatherer burials, it was a nodal zone criss-crossed by an extensive network of important routes, and it is characterized by a high environmental fragmentation due to the scarcity of fresh water sources. The aim of this paper is to build an empirical stable oxygen isotope baseline of terrestrial surface waters to assess the potentiality of tracing past human movem…
Spectral evolution simulation on leading multi-socket, multicore platforms
2011
Spectral evolution simulations based on the observed Very Long Baseline Interferometry (VLBI) radio-maps are of paramount importance to understand the nature of extragalactic objects in astrophysics. This work analyzes the performance and scaling of a spectral evolution algorithm on three leading multi-socket, multi-core architectures. We evaluate three parallel models with different levels of data-sharing: a sharing approach, a privatizing approach and a hybrid approach. Our experiments show that the data-privatizing model is reasonably efficient on medium scale multi-socket, multi-core systems (up to 48 cores) while regardless algorithmic and scheduling optimizations, sharing approach is …
Variability and polarization in the inner jet of 3C 395
2001
We present new results on the parsec-scale jet of the quasar 3C395, derived from VLBI polarization sensitive observations made in 1995.91 and 1998.50 at 8.4, 15.4 and 22.2 GHz. The observations show a complex one-sided jet extending up to 20 mas, with a projected magnetic field essentially aligned with the radio jet. The emission is strongly dominated, in total intensity and polarization, by the core and the inner jet region (of ~3 mas length). We have studied the details of this dominant region finding clear structural variations during this ~2.5 years period, in contrast with the apparent quietness of the jet structure inferred from lower resolution VLBI observations. We observe the eject…
Strongly decelerated expansion of SN 1979C
2002
We observed SN1979C in M100 on 4 June 1999, about twenty years after explosion, with a very sensitive four-antenna VLBI array at the wavelength of 18cm. The distance to M100 and the expansion velocities are such that the supernova cannot be fully resolved by our Earth-wide array. Model-dependent sizes for the source have been determined and compared with previous results. We conclude that the supernova shock was initially in free expansion for 6 +/- 2 yrs and then experienced a very strong deceleration. The onset of deceleration took place a few years before the abrupt trend change in the integrated radio flux density curves. We estimate the shocked swept-up mass to be about 1.6 solar masse…
Do Age and Sex Play a Role in the Intraocular Pressure Changes after Acrobatic Gymnastics?
2021
To evaluate the effects of an acrobatic gymnastics (AG) training session on intraocular pressure (IOP), a familiarization session was employed to confirm the participant’s suitability for the study. Forty-nine gymnasts (63.27% females, 18–40 years old) voluntarily agreed to participate. As age, sex, baseline IOP, and central corneal thickness (CCT) were considered as potential predictors of the IOP variations, in the second session measurements of the above parameters were taken before and after 90 min of AG. A mixed-factorial analysis of variance evaluated differences. Linear regression was conducted to potentially predict the IOP variation with the exercise. After the scheduled exercise, …
Establishing a Reference Baseline for Midday Stem Water Potential in Olive and Its Use for Plant-Based Irrigation Management
2021
12 páginas.- 7 figuras.- 4 tablas.- 55 referencias.-
Entrepreneurial universities: A bibliometric analysis within the business and management domains
2021
Abstract This study presents a bibliometric analysis of scientific publications investigating entrepreneurial universities in the business and management fields. The authors collected 511 documents from the Web of Science and analysed them using Bibliometrix, an RStudio package for performance analysis and science mapping. The study aims to provide an overview of the evolution of research about this topic and describe the structures (i.e., conceptual, social, and intellectual) characterising it. It discusses the results to identify the main areas addressed so far and highlight gaps in the literature, offering avenues for possible future research. The results show that publications on entrep…