scholarly journals Is there a non-stationary γ-ray emission zone 42 pc from the 3C 279 core?

2019 ◽  
Vol 630 ◽  
pp. A56 ◽  
Author(s):  
V. M. Patiño-Álvarez ◽  
S. A. Dzib ◽  
A. Lobanov ◽  
V. Chavushyan
Keyword(s):  
Gamma Rays ◽  
Gamma Ray ◽  
Rank Correlation ◽  
Spearman Rank Correlation ◽  
Superluminal Velocity ◽  
Γ Ray ◽  
Gamma Ray Emission ◽  
Radio Measurements ◽  
The Relationship ◽  
Region Feature

We investigate the relationship between the variable gamma-ray emission and jet properties in the blazar 3C 279 by combining the Fermi-LAT data spanning a period of eight years and concurrent radio measurements made at multiple epochs with VLBA at 15 and 43 GHz within the MOJAVE and VLBA-BU monitoring programmes. The aim of this paper is to compare the flux variability of the different components found in the VLBA observations, to the variability in the gamma-rays. This analysis helps us to investigate whether any of the jet components can be associated with the gamma-ray variability. Through Spearman rank correlation we found that the gamma-ray variability is correlated with a particular region (feature B in the MOJAVE images) downstream from the observed base (core) of the jet. This jet component is therefore a likely location where an important fraction of the variable gamma-ray emission is produced. We also calculated the average proper motion of the component with respect to the VLBA core and found that it moves at an apparent superluminal velocity of (3.70 ± 0.35)c, implying that one of the gamma-ray emission zones is not stationary. This jet component is also found between 6.86 mas and 8.68 mas, which translates to a distance from the radio core of at least 42 pc.

scholarly journals The Flare of 1989 September 9, 09:09 UT: Does Coronal Loop Collision Initiate Efficient Gamma-Ray Emission?

1994 ◽  
Vol 142 ◽  
pp. 707-711
Author(s):  
H. Aurass ◽  
A. Hofmann ◽  
E. Rieger
Keyword(s):  
Current Sheet ◽  
Gamma Rays ◽  
Coronal Loop ◽  
Gamma Ray ◽  
High Energy ◽  
X Rays ◽  
Subject Headings ◽  
Γ Ray ◽  
Gamma Ray Emission ◽  
Magnetogram Data

AbstractVector magnetogram data and Hα pictures together with data published by Chupp et al. lead us to conjecture that in the presented case a contact between the rising two-ribbon flare current sheet and a coronal loop connecting two nearby plage regions initiates efficient high-energy γ-ray emission.Subject headings: Sun: corona — Sun: flares — Sun: X-rays, gamma rays

scholarly journals Radio jets and gamma-ray emission in radio-silent narrow-line Seyfert 1 galaxies

2018 ◽  
Vol 614 ◽  
pp. L1 ◽  
Author(s):  
A. Lähteenmäki ◽  
E. Järvelä ◽  
V. Ramakrishnan ◽  
M. Tornikoski ◽  
J. Tammi ◽  
...  
Keyword(s):  
Gamma Rays ◽  
Supernova Remnants ◽  
Gamma Ray ◽  
Spiral Galaxies ◽  
Narrow Line ◽  
Radio Jets ◽  
Relativistic Jet ◽  
Gamma Ray Emission

We have detected six narrow-line Seyfert 1 (NLS1) galaxies at 37 GHz that were previously classified as radio silent and two that were classified as radio quiet. These detections reveal the presumption that NLS1 galaxies labelled radio quiet or radio silent and hosted by spiral galaxies are unable to launch jets to be incorrect. The detections are a plausible indicator of the presence of a powerful, most likely relativistic jet because this intensity of emission at 37 GHz cannot be explained by, for example, radiation from supernova remnants. Additionally, one of the detected NLS1 galaxies is a newly discovered source of gamma rays and three others are candidates for future detections.

scholarly journals Interactional Justice and Employees’ Commitment to Supervisor in Nigerian Health Sector

2015 ◽  
Vol 2 (5) ◽  
pp. 7-17 ◽  
Author(s):  
Ajogwu Akoh ◽  
Edwinah Amah
Keyword(s):  
Health Sector ◽  
Rank Correlation ◽  
Interactional Justice ◽  
Survey Questionnaire ◽  
Spearman Rank Correlation ◽  
Interpersonal Justice ◽  
Informational Justice ◽  
Spearman Rank ◽  
The Relationship ◽  
Spearman Rank Correlation Coefficient

This research was designed to study the relationship between interactional justice and employees’ commitment to supervisor in Nigerian health sector. A self-administered survey questionnaire was sent out to a sample size of 103 employees, resulting in 99 responses out of which 13 copies of the questionnaire were not statistically usable. The Spearman rank correlation coefficient was used for data analysis, and our findings reveal that employees who have received fair informational and interpersonal treatments commit themselves to their supervisors. We discovered that the degree of influence exerted by interpersonal justice on employees’ commitment to supervisor was stronger than that of informational justice. We concluded that employees attach themselves to supervisors that are fair in communication and relationship. The fairness of interaction and communication boost employees’ confidence, impacting positively on employees’ commitment to supervisor and making employees see themselves as part owners in the organization. We, therefore, recommended that organizational managers or supervisors should communicate and relate properly with employees, in order to satisfy their customers and other stakeholders.

scholarly journals What do Gamma Rays tell us about the ISM?: New Insight from the Compton Observatory

1996 ◽  
Vol 169 ◽  
pp. 437-446 ◽  
Author(s):  
Hans Bloemen
Keyword(s):  
Interstellar Medium ◽  
Gamma Rays ◽  
Gamma Ray ◽  
Line Emission ◽  
Cosmic Ray ◽  
Gamma Ray Astronomy ◽  
Early Results ◽  
The Galaxy ◽  
Γ Ray ◽  
Insight Into

Gamma-ray astronomy has become a rich field of research and matured significantly since the launch of NASA's Compton Gamma Ray Observatory in April 1991. Studies of the diffuse γ-ray emission of the Galaxy can now be performed in far more detail and extended into the MeV regime, including both continuum and line emission. These studies provide unique insight into various aspects of the interstellar medium, in particular of the cosmic-ray component. This paper gives a brief review on the diffuse Galactic γ-ray emission and summarizes early results and prospects from the Compton Observatory.

Gastric axial forces in experimentally delayed and accelerated gastric emptying

1993 ◽  
Vol 264 (5) ◽  
pp. G928-G934 ◽  
Author(s):  
C. M. Prather ◽  
M. Camilleri ◽  
G. M. Thomforde ◽  
L. A. Forstrom ◽  
A. R. Zinsmeister
Keyword(s):  
Gastric Emptying ◽  
Rank Correlation ◽  
Longitudinal Axis ◽  
Force Transducer ◽  
Spearman Rank Correlation ◽  
Distal Stomach ◽  
Axial Forces ◽  
Gastroduodenal Motility ◽  
The Relationship ◽  
Infusion Period

The aim of this study was to assess the relationship between altered axial forces and gastric emptying of solids by experimentally inhibiting or stimulating gastric axial forces by intraduodenal lipid or intravenous erythromycin, respectively. In 15 healthy volunteers, we simultaneously measured gastric emptying of solids by scintigraphy, gastroduodenal motility by manometry, and forces along the longitudinal axis of the distal stomach by an axial force transducer. When 25% of the radiolabel had emptied from the stomach, subjects (n = 5 in each group) received normal saline (controls), intraduodenal lipid, or intravenous erythromycin. The test period consisted of the infusion period (10 min) and the subsequent 30 min. Lipid significantly reduced and erythromycin increased axial forces compared with control (lipid: median 0.6 N [0-1.4 interquartile range (IQR)]; erythromycin: median 18.2 N (16.5-20.5 IQR); control: median 4.7 N (3.9-5.2 IQR); P < 0.01). Similarly, antral phasic pressure activities were different relative to control. Gastric axial forces correlated significantly with gastric emptying (Spearman rank correlation = 0.86; P < 0.01). These data are consistent with the hypothesis that axial forces affect gastric emptying of solids and suggest that measurement of axial forces provides an assessment of overall gastric propulsion during the emptying of solids.

scholarly journals Searches for IceCube neutrinos from blazar flares using correlations with gamma-ray lightcurves

2019 ◽  
Vol 207 ◽  
pp. 02007
Author(s):  
Christoph Raab ◽  
Juan Antonio Aguilar Sánchez
Keyword(s):  
Cosmic Rays ◽  
Gamma Rays ◽  
Gamma Ray ◽  
Hadronic Interactions ◽  
Astrophysical Neutrinos ◽  
Gamma Ray Emission ◽  
Selection Of

Blazars have long been considered as accelerator candidates for cosmic rays. In such a scenario, hadronic interactions in the jet would produce neutrinos and gamma rays. Correlating the astrophysical neutrinos detected by IceCube with the gamma-ray emission from blazars could therefore help elucidate the origin of cosmic rays. In our method we focus on periods where blazars show an enhanced gamma-ray flux, as measured by Fermi-LAT, thereby reducing the background of the search. We present results for TXS 0506+056, using nearly 10 years of IceCube data and discuss them in the context of other recent analyses on this source. In addition, we give an outlook on applying this method in a stacked search for the combined emission from a selection of variable Fermi blazars.

scholarly journals Study on Induced Current of Iron Plate Irradiated by Pulsed Gamma Rays

2018 ◽  
Vol 53 ◽  
pp. 01007
Author(s):  
Yinghong Zuo ◽  
Maoyu Zhang ◽  
Guoxin Cheng ◽  
Shengli Niu
Keyword(s):  
Gamma Rays ◽  
Gamma Ray ◽  
Transient Current ◽  
Current Response ◽  
Induced Current ◽  
Metal Component ◽  
Iron Plate ◽  
Gamma Ray Irradiation ◽  
Charge Deposition ◽  
The Relationship

To obtain the transient current response law of the metal component irradiated by pulsed gamma rays, the pulsed gamma ray irradiation experiment of the iron plate was carried out on “Qiangguang-I” accelerator. The transient current of iron plate generated by pulsed gamma rays was measured and analysed, and the relationship between the amplitude of pulse current and the dose rate of gamma rays was obtained. The results show that the current response sensitivity of the iron plate is about 5.7×10-7(A/m2)/(Gy/s) when the gamma rays with the energy of 0.8 MeV irradiate the iron plate. The charge deposition rate in the iron plate can be obtained by Monte Carlo simulation, and then it can be converted to gamma ray induced current of the metal component irradiated by gamma rays.

High-Energy Solar Gamma-Ray Observations

1998 ◽  
Vol 11 (2) ◽  
pp. 755-758
Author(s):  
M. Yoshimori ◽  
N. Saita ◽  
A. Shiozawa
Keyword(s):  
Particle Acceleration ◽  
Gamma Rays ◽  
Solar Flares ◽  
Gamma Ray ◽  
Solar Maximum ◽  
High Energy ◽  
The Sun ◽  
Long Duration ◽  
New Findings ◽  
Gamma Ray Emission

In the last solar maximum, gamma-rays associated with solar flares were observed with GRANAT, GAMMA-1, CGRO and YOHKOH. The gamma-ray energies ranged from 100 keV to a few GeV. We obtained several new findings of gamma-ray emission on the Sun: (1) Gamma-ray production in the corona, (2) GeV gamma-ray production in very long duration flares, (3) Electron-rich flares, (4) Gamma-ray lines and solar atmospheric abundances and (5) Possible location of gamma-ray emission. We present the observations of these new findings and discuss high energy phenomena relating to particle acceleration and gamma-ray production during solar flares.

Histological architectures of clear cell carcinoma and their correlation to clinicopathologic features.

2016 ◽  
Vol 34 (2_suppl) ◽  
pp. 576-576
Author(s):  
Go Kimura ◽  
Hayato Takeda ◽  
Jun Akatsuka ◽  
Yuki Endo ◽  
Yukihiro Kondo
Keyword(s):  
Cell Carcinoma ◽  
Microvessel Density ◽  
Tumor Size ◽  
Clear Cell ◽  
Clear Cell Carcinoma ◽  
Rank Correlation ◽  
Tumor Grade ◽  
Spearman Rank Correlation ◽  
High Attenuation ◽  
The Relationship

576 Background: The aim of this study is to clarify the relationship between histological architectures (HA) and clinicopathological features (CF) in clear cell carcinoma (CCC). Methods: Between 1984 and 2014 nephrectomy or partial nephrectomy were performed in 723 renal cell carcinoma cases in our hospital. Among them 603 cases (83.4%) were CCC. We reviewed the pathological reports and found 556 CCC cases had description of HA. The relationship between HA and CF were investigated. Results: HA were as follows: small acinar (SA)/acinar (A) in 453 cases (81.5%), large acinar (LA)/solid (S) in 113 (20.3%), papillary (P) in 54 (9.7%), Cystic (C) in 121 (21.8%) and tubular in 53 (9.5%). By the Spearman rank correlation, significant correlation was observed between HA and tumor grades: SA/A (rho -0.408, p < 0.0001), LA/S (0.567, p < 0.0001), P (0.257, p < 0.0001), C (-0.241, p < 0.0001). Acinar sizes were correlated with tumor grade (0.541, p < 0.0001), tumor size (0.435, p < 0.0001) and local stage (0.414, p < 0.0001). LA/S or P showed low microvessel density evaluated by CD31 immunostaining, which resulted in weaker attenuation in corticomedullary phase of enhancement CT. On the contrary SA had high microvessel density and high attenuation after enhancement. Conclusions: HA is well-correlated with tumor grade, tumor size and local stage, and could be predicted by dynamic CT pattern preoperatively.

Gamma-ray production in the 170Er(p,n)170Tm nuclear reaction

Open Physics ◽  
2010 ◽  
Vol 8 (4) ◽  
Author(s):  
Alexandru Mihailescu ◽  
Gheorghe Cata-Danil
Keyword(s):  
High Resolution ◽  
Energy Range ◽  
Nuclear Reaction ◽  
Gamma Rays ◽  
Compound Nucleus ◽  
Beam Energy ◽  
Gamma Ray ◽  
Excitation Functions ◽  
Γ Ray ◽  
First Time

AbstractFor the first time discrete gamma-rays following the nuclear reaction 170Er(p,n)170Tm with enriched target were measured with a high resolution GeHP spectrometer. Protons delivered by the Bucharest FN Tandem Van de Graaff accelerator bombarded a thin self-supporting film of enriched erbium. Measured γ-ray energies (Eγ), their relative intensities (Iγ) and corresponding excitation functions for the beam energy range 2.0–3.6 MeV are reported in the present work. The measured excitation functions were fairly well reproduced by compound nucleus calculations based on the Hauser-Feshbach formalism.

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