scholarly journals Constraining the transient high-energy activity of FRB 180916.J0158+65 with Insight–HXMT follow-up observations

2020 ◽  
Vol 642 ◽  
pp. A160
Author(s):  
C. Guidorzi ◽  
M. Orlandini ◽  
F. Frontera ◽  
L. Nicastro ◽  
S. L. Xiong ◽  
...  
Keyword(s):  
Broad Band ◽  
Active Phase ◽  
Effective Area ◽  
High Energy ◽  
Broad Energy Range ◽  
Released Energy ◽  
Fast Radio Burst ◽  
High Energy Emission ◽  
Broad Energy

Context. A link has finally been established between magnetars and fast radio burst (FRB) sources. Within this context, a major issue that remains unresolved pertains to whether sources of extragalactic FRBs exhibit X/γ-ray outbursts and whether this is correlated with radio activity. If so, the subsequent goal is to identify these sources. Aims. We aim to constrain possible X/γ-ray burst activity from one of the nearest extragalactic FRB sources currently known. This is to be done over a broad energy range by looking for bursts over a range of timescales and energies that are compatible with those of powerful flares from extragalactic magnetars. Methods. We followed up on the observation of the as-yet nearest extragalactic FRB source, located at a mere 149 Mpc distance, namely, the periodic repeater FRB 180916.J0158+65. This took place during the active phase between 4 and 7 February 2020, using the Insight–Hard X-ray Modulation Telescope (Insight–HXMT). By taking advantage of the combination of broad-band wavelengths, a large effective area, and several independent detectors at our disposal, we searched for bursts over a set of timescales from 1 ms to 1.024 s with a sensitive algorithm that had been previously characterised and optimised. Moreover, through simulations, we studied the sensitivity of our technique in the released energy-duration phase space for a set of synthetic flares and assuming a range of different energy spectra. Results. We constrain the possible occurrence of flares in the 1−100 keV energy band to E <  1046 erg for durations Δ t <  0.1 s over several tens of ks exposure. Conclusions. We can rule out the occurrence of giant flares similar to the ones that were observed in the few cases of Galactic magnetars. The absence of reported radio activity during our observations prevents us from making any determinations regarding the possibility of simultaneous high-energy emission.

scholarly journals Simultaneous observations of the blazar PKS 2155−304 from ultra-violet to TeV energies

2020 ◽  
Vol 639 ◽  
pp. A42
Author(s):  
H. Abdalla ◽  
R. Adam ◽  
F. Aharonian ◽  
F. Ait Benkhali ◽  
E. O. Angüner ◽  
...  
Keyword(s):  
Ultra Violet ◽  
High Energy ◽  
X Rays ◽  
Broad Energy Range ◽  
Significant Contamination ◽  
Multi Wavelength ◽  
High Energy Emission ◽  
Broad Energy ◽  
Made In ◽  
Significant Flux

Here we report the results of the first ever contemporaneous multi-wavelength observation campaign on the BL Lac object PKS 2155−304 involving Swift, NuSTAR, Fermi-LAT, and H.E.S.S. The use of these instruments allows us to cover a broad energy range, which is important for disentangling the different radiative mechanisms. The source, observed from June 2013 to October 2013, was found in a low flux state with respect to previous observations but exhibited highly significant flux variability in the X-rays. The high-energy end of the synchrotron spectrum can be traced up to 40 keV without significant contamination by high-energy emission. A one-zone synchrotron self-Compton model was used to reproduce the broadband flux of the source for all the observations presented here but failed for previous observations made in April 2013. A lepto-hadronic solution was then explored to explain these earlier observational results.

scholarly journals High-Energy Multimessenger Transient Astrophysics

2019 ◽  
Vol 69 (1) ◽  
pp. 477-506 ◽  
Author(s):  
Kohta Murase ◽  
Imre Bartos
Keyword(s):  
Time Domain ◽  
Particle Production ◽  
High Energy ◽  
High Energy Particle ◽  
Energy Particle ◽  
Transient Phenomena ◽  
New Era ◽  
Astrophysical Objects ◽  
High Energy Emission

The recent discoveries of high-energy cosmic neutrinos and gravitational waves from astrophysical objects have led to a new era of multimessenger astrophysics. In particular, electromagnetic follow-up observations triggered by these cosmic signals have proved to be highly successful and have brought about new opportunities in time-domain astronomy. We review high-energy particle production in various classes of astrophysical transient phenomena related to black holes and neutron stars, and discuss how high-energy emission can be used to reveal the underlying physics of neutrino and gravitational-wave sources.

scholarly journals Gravitational-wave follow-up with CTA after the detection of GRBs in the TeV energy domain

2019 ◽  
Vol 490 (3) ◽  
pp. 3476-3482 ◽  
Author(s):  
I Bartos ◽  
K R Corley ◽  
N Gupte ◽  
N Ash ◽  
Z Márka ◽  
...  
Keyword(s):  
Gravitational Wave ◽  
Gamma Ray ◽  
The United States ◽  
High Energy ◽  
Cherenkov Telescopes ◽  
Wave Event ◽  
Energy Domain ◽  
Time Requirements ◽  
High Energy Emission

ABSTRACT The recent discovery of TeV emission from gamma-ray bursts (GRBs) by the MAGIC and H.E.S.S. Cherenkov telescopes confirmed that emission from these transients can extend to very high energies. The TeV energy domain reaches the most sensitive band of the Cherenkov Telescope Array (CTA). This newly anticipated, improved sensitivity will enhance the prospects of gravitational-wave follow-up observations by CTA to probe particle acceleration and high-energy emission from binary black hole and neutron star mergers, and stellar core-collapse events. Here we discuss the implications of TeV emission on the most promising strategies of choice for the gravitational-wave follow-up effort for CTA and Cherenkov telescopes more broadly. We find that TeV emission (i) may allow more than an hour of delay between the gravitational-wave event and the start of CTA observations; (ii) enables the use of CTA’s small size telescopes that have the largest field of view. We characterize the number of pointings needed to find a counterpart. (iii) We compute the annual follow-up time requirements and find that prioritization will be needed. (iv) Even a few telescopes could detect sufficiently nearby counterparts, raising the possibility of adding a handful of small-sized or medium-sized telescopes to the network at diverse geographic locations. (v) The continued operation of VERITAS/H.E.S.S./MAGIC would be a useful compliment to CTA’s follow-up capabilities by increasing the sky area that can be rapidly covered, especially in the United States and Australia, in which the present network of gravitational-wave detectors is more sensitive.

scholarly journals Search for High Energy emission from GRBs with MAGIC

2016 ◽  
Vol 12 (S324) ◽  
pp. 70-73
Author(s):  
Alessio Berti ◽  
Keyword(s):  
Gamma Ray ◽  
High Energy ◽  
Cherenkov Telescopes ◽  
Gamma Ray Imaging ◽  
Very High Energy ◽  
Γ Rays ◽  
High Energy Emission ◽  
The Universe ◽  
Very High

AbstractGamma-Ray Bursts (GRBs) are the most violent explosions in the Universe, releasing a huge amount of energy in few seconds. While our understanding of the prompt and the afterglow phases has increased with Swift and Fermi, we have very few information about their High Energy (HE, E ≲ 100) emission components. This requires a ground-based experiment able to perform fast follow-up with enough sensitivity above ~ 50 GeV. The MAGIC (Major Atmospheric Gamma-ray Imaging Cherenkov) telescopes have been designed to perform fast follow-up on GRBs thanks to fast slewing movement and low energy threshold (~ 50 GeV). Since the beginning of the operations, MAGIC followed-up 89 GRBs in good observational conditions. In this contribution the MAGIC GRBs follow-up campaign and the results which could be obtained by detecting HE and Very High Energy (VHE, E ≳ 100 GeV) γ-rays from GRBs will be reviewed.

scholarly journals Localizing the γ-ray emitting region in the blazar TXS 2013+370

2020 ◽  
Vol 634 ◽  
pp. A112
Author(s):  
E. Traianou ◽  
T. P. Krichbaum ◽  
B. Boccardi ◽  
R. Angioni ◽  
B. Rani ◽  
...  
Keyword(s):  
Correlation Analysis ◽  
Cross Correlation ◽  
Broad Band ◽  
Gaussian Model ◽  
High Energy ◽  
Geometrical Properties ◽  
The Core ◽  
Energy Emission ◽  
Cross Correlation Analysis ◽  
High Energy Emission

Aims. The γ-ray production mechanism and its localization in blazars are still a matter of debate. The main goal of this paper is to constrain the location of the high-energy emission in the blazar TXS 2013+370 and to study the physical and geometrical properties of the inner jet region on sub-pc scales. Methods. TXS 2013+370 was monitored during 2002–2013 with VLBI at 15, 22, 43, and 86 GHz, which allowed us to image the jet base with an angular resolution of ≥0.4 pc. By employing CLEAN imaging and Gaussian model-fitting, we performed a thorough kinematic analysis at multiple frequencies, which provided estimates of the jet speed, orientation, and component ejection times. Additionally, we studied the jet expansion profile and used the information on the jet geometry to estimate the location of the jet apex. VLBI data were combined with single-dish measurements to search for correlated activity between the radio, mm, and γ-ray emission. For this purpose, we employed a cross-correlation analysis, supported by several significance tests. Results. The high-resolution VLBI imaging revealed the existence of a spatially bent jet, described by co-existing moving emission features and stationary features. New jet features, labeled as A1, N, and N1, are observed to emerge from the core, accompanied by flaring activity in radio/mm- bands and γ-rays. The analysis of the transverse jet width profile constrains the location of the mm core to lie ≤2 pc downstream of the jet apex, and also reveals the existence of a transition from parabolic to conical jet expansion at a distance of ∼54 pc from the core, corresponding to ∼1.5 × 106 Schwarzschild radii. The cross-correlation analysis of the broad-band variability reveals a strong correlation between the radio-mm and γ-ray data, with the 1 mm emission lagging ∼49 days behind the γ-rays. Based on this, we infer that the high energy emission is produced at a distance of the order of ∼1 pc from the jet apex, suggesting that the seed photon fields for the external Compton mechanism originate either in the dusty torus or in the broad-line region.

scholarly journals The Astro-E Mission

1998 ◽  
Vol 188 ◽  
pp. 75-78 ◽  
Author(s):  
Y. Ogawara
Keyword(s):  
High Sensitivity ◽  
High Energy ◽  
High Energy Resolution ◽  
High Energy Astrophysics ◽  
X Ray ◽  
The Past ◽  
Broad Energy Range ◽  
Indispensable Tool ◽  
Year 2000 ◽  
Broad Energy

The past three decades have seen an explosion in high-energy astrophysics. We have found X-ray astronomy to be an indispensable tool in understanding our Universe. The discipline has become mature, and future X-ray observatories must be more highly specialized. High-resolution spectroscopic imaging in the band above 2 keV, systematically exploited by ASCA, has led to much new astrophysical knowledge. ASCA has also been playing a particularly important role in studying sources hidden behind dense material. Astro-E, the successor of ASCA, is scheduled for launch in the year 2000 by the Institute of Space and Astronautical Science (ISAS) with its newly developed M-V rocket (Ogawara & Inoue 1997). Our new Astro-E observatory features high energy resolution and high sensitivity over the broad energy range 0.5 keV to 600 keV. The general emphasis of the observatory is to provide large collecting areas at higher energies, with angular resolution good enough to avoid the confusion limit. This paper provides a brief description of the performance of the Astro-E instruments.

scholarly journals MWL Picture Of The Blazar S5 0716+714 During Its Brightest Outburst

2016 ◽  
Author(s):  
Marina Manganaro ◽  
Giovanna Pedaletti ◽  
Marlene Doert ◽  
Denis Bastieri ◽  
Vandad Fallah Ramazani ◽  
...  
Keyword(s):  
Time Window ◽  
Spectral Energy Distribution ◽  
Broad Band ◽  
High Energy ◽  
Spectral Energy ◽  
Time Variability ◽  
Multi Wavelength ◽  
Very High Energy ◽  
Very High

S5 0716+714 is a well known BL-Lac object, one of the brightest and most active blazars. The discovery in the Very High Energy band (VHE, E &gt; 100 GeV) by MAGIC happened in 2008. In January 2015 the source went through the brightest optical state ever observed, triggering MAGIC follow-up and a VHE detection with ~ sigma significance (ATel #6999). Rich multi-wavelength coverage of the flare allowed us to construct the broad-band spectral energy distribution of S5 0716+714 during its brightest outburst. In this work we will present the preliminary analysis of MAGIC and Fermi-LAT data of the flaring activity in January and February 2015 for the HE and VHE band, together with radio (Metsahovi, OVRO, VLBA, Effelsberg), sub-millimeter (SMA), optical (Tuorla, Perkins, Steward, AZT-8+ST7, LX-200, Kanata), X-ray and UV (Swift-XRT and UVOT), in the same time-window and discuss the time variability of the MWL light curves during this impressive outburst.

1524: High Energy Tumt and Adjuvant Alpha Blockade Significantly Improves Symptoms in Men with Cathegory IIIB (CPPS) Prostatitis. A Prospective Non-Randomized with 5 Years Follow Up

2006 ◽  
Vol 175 (4S) ◽  
pp. 491-492
Author(s):  
Sybille Mariharl ◽  
Christian Seitz ◽  
Bob Djavan ◽  
Matthias Walderl ◽  
Michael Dobrovits ◽  
...  
Keyword(s):  
High Energy ◽  
Alpha Blockade

High‐Energy Emission from the TeV Blazar Markarian 501 during Multiwavelength Observations in 1996

1999 ◽  
Vol 514 (1) ◽  
pp. 138-147 ◽  
Author(s):  
J. Kataoka ◽  
J. R. Mattox ◽  
J. Quinn ◽  
H. Kubo ◽  
F. Makino ◽  
...  
Keyword(s):  
High Energy ◽  
Energy Emission ◽  
High Energy Emission ◽  
Multiwavelength Observations

scholarly journals Telephone follow-up of oncology patients: the contribution of the nurse specialist for a Service-Dominant Logic in hospital

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Corinne Rochette ◽  
Anne Sophie Michallet ◽  
Stéphanie Malartre-Sapienza ◽  
Sophie Rodier
Keyword(s):  
Patient Activation ◽  
Central Element ◽  
Cancer Control ◽  
Control Unit ◽  
Active Phase ◽  
Nurse Specialist ◽  
Structured Interviews ◽  
Service Dominant Logic ◽  
Dominant Logic

Abstract Background The French healthcare system is characterised by a shift towards outpatient care and the desire to develop telemedicine affirmed in the collective commitment “Ma santé 2022” presented by President Macron in 2018. In France, remote patient follow up has recently been developed in the active phase of cancer treatment inspired by the patient navigation approach used in other countries. According to Service-Dominant Logic (S-D L), patients become more active. Their role in co-production of services is strengthened and their behaviours changed. Telephone follow-ups can contribute to modifying the relationship between the patient and the nurse navigators in charge of it, moving logically from a passive attitude from the patient to a more active one. Methods This study was carried out at Léon Bérard, a cancer control unit, in France. It concerned patients treated in an oncohaematology department, who benefited from telephone follow-ups carried out by nurse specialists during the active phase of their treatment. The multidisciplinary research team including social science researchers, physicians and carers developed a research protocol to study this pilot case. Essentially based on a qualitative approach, it was validated by the centre’s management to study this follow-up on patients’ behaviours. The 1st phase of the research, based on 24 semi-structured interviews with patients undergoing treatment undertaken from November 2018 to September 2019, is presented. Results The Telephone follow-up was a positive experience for all patients. The action of the nurse specialist helped to develop certain dimensions of in-role and extra-role behaviour that created value. The patients’ discourse has reported a positive follow-up in its clinical dimensions, its psychological dimensions and an enhanced quality of life. We detected a patient activation through their roles but it remained limited. The telephone follow-up also created a patient dependency. Conclusions The telephone follow-up is a relevant tool for patients undergoing treatment and it deserves to be more widely deployed. It brings comfort and creates a relationship based on trust but at the same time it limits the emancipation of the patient, which is a central element of the S-D logic and its empowerment.

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